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11-04-2005 Post does not mapped to Knowledge Tree
morricab
Posts 51
Joined on 07-13-2005

Post #: 21
Post ID: 1649
Reply to: 1646
Re: autoformers and OTLs ....
Hi Romy,
Not sure exactly what you mean by SET-minded speakers.  Please elaborate on that issue.  I don't quite see what about your horns would make an OTL perform any worse than a SET.  What I proposed to you, the concept of a OTL SET would seem to be a possible option in that case.  It seems that perhaps the "deconstruction" of the sound that you don't like could be related to the fact that most OTLs are push pull in one manner or another.  Unless of course you like the sound the transformer adds overall.  I don't know that there exists a truly transparent transformer, do you?
11-04-2005 Post does not mapped to Knowledge Tree
morricab
Posts 51
Joined on 07-13-2005

Post #: 22
Post ID: 1651
Reply to: 1647
Re: Better among worst?

Hi Thorsten,

I understand what you are saying and with regard to the particular preamp in question and you may well be right as there is no mention by the manufacturer what brand of autoformers are in use (or if they roll their own).  I am curious about the S&B transformers though.  If I were to explore that avenue are the silver ones truly superior to the copper ones or is the difference slight?  Are there better ones to be had than the S&B?

I am not sure what you mean by stressed out because the music to my ears and my experienced listening friends we found the music to be rather effortless with quite lifelike dynamics (perhaps you think of this as stressed??).  I heard the amps twice now, once with a big pair of Odeon Number 32 horns (96db watt) and this sounded particularly effortless.  This year was with the Living Voice Avatar OBX-R speakers (I think around 90db), which to be honest upon seeing them in the room significantly lowered my expectations.  However, the sound was still surprisingly dynamic with really great tonality.  I also had the sensation of hearing everything from the recording.  I did hear the coloration in the speaker but that it was low is as it should be and didn't detract too significantly from the whole experience.  The strengths I heard: transparency (high resolution as well), tonal correctness, and dynamic contrasts were consistent both years even though the overall "flavor" of the sound was a bit different (probably a result of the speakers).  What speakers did you hear them with?

Its a pity they use an inferior pot in such an expensive preamp.  Of course I didn't have the opportunity to dismantle one to look inside Smile

What exactly did you find to not be so remarkable?  What do you pay attention to in particular and ignore.  I tend not to ignore any one aspect of reproduction because I think they are all imortant.  
The biggies I am perhaps most interested in and unwilling to compromise about are:

Tone and harmonic correctness including attack and decay
Transparency and noise floor, meaning that there is no sense of the something putting a veil over the music.
Dynamics (particularly dynamic contrast) and how low a volume sound can be reproduced and still sound life-like
Overall neutrality (meaning no wild swings in frequency response) including coloration from speakers and electronics
Resolution, meaning how easily are instruments separated spatially and tonally in a mix of instruments and how life-like a sound is at low levels in the presence of a bigger sound (eg. a light tap on a ride cymbal coming through in a lifelike manner during a high level trumpet blat). 
Even dispersion of sound at all frequencies or restricted but uniform dispersion.

 

11-04-2005 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,540
Joined on 05-28-2004

Post #: 23
Post ID: 1652
Reply to: 1649
a lightly a different subject: OTL

I know about the transformers much less then you might imagine. I know if they work of not but why they do or do not do so I have no idea. Some people believe that they do know, I feel that many of then have in fact no really idea as well. Transformer is really the “terra incognita” of audio, at least for me….

Anyhow…

Regarding the OTL, although it is a lightly a different subject I detected that if we have an abstract OTL amp then a relative performance of this OTL will wary with the impedance and sensitively of speakers. However, it is not only about the ability or disability to work against complex impedance but rather the dynamic-harmonic characteristics of sound that become radically different since the speakers damp/react to the OTL (or OTL react to them) I think if to have I would say 4-5 ways high sensitively and high transient response installation and to be able to leverage impedance of EACH channel assuring the a given OTL produce the same harmonic structure within the widest dynamic range and within the same frequency range then it would be possible to make an OTL to perform correctly. Meanwhile an OTL driving a full-range conventional loudspeaker never perform well unless it drive a slow and dead loudspeaker of high-flat impedance and with sensitively of 75dB

Rgs,
Romy the Cat


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
11-04-2005 Post does not mapped to Knowledge Tree
Thorsten


United Kingdom
Posts 65
Joined on 12-06-2004

Post #: 24
Post ID: 1653
Reply to: 1651
Re: Better among worst?

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Hi,

 morricab wrote:
no mention by the manufacturer what brand of autoformers are in use (or if they roll their own). 

There is one thing I can say. Nickel Lams are bright, shiny and light coloured. Steel lams are dark and dull. I can tell you what is inside those bobbins in that particular case.

 morricab wrote:
I am curious about the S&B transformers though.  If I were to explore that avenue are the silver ones truly superior to the copper ones or is the difference slight?  Are there better ones to be had than the S&B?


First, there are differences between copper and silver, I tend towards the copper versions, they sound to my ears more balanced, but in some aspects the silver TX's are better but their virtues and vices are not as well balanced. Silver is certainly even closer to "straight wire" than copper, but tends towards a slight thinness and whispyness....

Sort of like the taste of the warranted genuine snark:
 
"The first is the taste, Which is meager and hollow, but crisp: Like a coat that is rather too tight in the waist, With a flavor of Will-o-the-wisp."

It's a system thing I think. To me the slightly looser, fuller and resonant sound of the copper version seems to please my esthetic sensibilities more.

 morricab wrote:
I am not sure what you mean by stressed out


I do not know how to describe it any better.

Let me say that the difference between a true virtuoso and an excellent musician is not that they cannot both play the same piece, be exact on the same difficult notes and all that, the difference is that virtuoso makes is look, sound and seem as if it is the easiest and slightest thing in the world, while with a merely good musician you notice somehow how hard he has to work to "get there". It is this kind of feel I get from OTL's. I have heard Graaf, various Croft ones, Atmasphere, the Einstein and a variety of DIY ones. I find that the more output valves and the lower impedance ones the designer throws at the job the more the strained sound goes away, but the evils of paralleled devices (a seeming loss of defintion, a blurring of focus to wit) become more noticable.

For me in order to use OTL's you either need to go for ESL's directly driven by the Valves (a friend uses such a system, a massive one and it is indeed very good) of for high impedance dynamic Drivers, such as Philips used to make.

Maybe a line source with a large number of good quality small diameter drivers all in series might work, but again we have multiple devices.

I'd love to a 2500 Ohm version of the Supravox fiedcoil driver I use now.

 morricab wrote:
What speakers did you hear them with?


Odeon.

 morricab wrote:
Its a pity they use an inferior pot in such an expensive preamp.  Of course I didn't have the opportunity to dismantle one to look inside Smile


I have german reviews (Image HiFi) of all these items, they have quite detailed Photos.

 morricab wrote:
What exactly did you find to not be so remarkable? 


Having heard (different model but similar) Odeons before with SE Amp's I just felt that things dulled, uninteresting, laking in aliveness, mechanical.

 morricab wrote:
What do you pay attention to in particular and ignore. 


Dynamics (and I mean dynamics and not compression) micro & macro and "tone" plus emotional involvement (this where the "stress" becomes noticable) - does the music move me?

Ciao T




"It is to Madame Justice that I dedicate this concerto, in view of the holiday she seems to have taken from these parts." V
11-04-2005 Post does not mapped to Knowledge Tree
morricab
Posts 51
Joined on 07-13-2005

Post #: 25
Post ID: 1656
Reply to: 1653
Re: Better among worst?

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Hi,

Thanks for the info about transformers.  It is as I expected, however, that these passive devices are not passive sonically at all. I agree with you that the higher quality of the transformers should lessen the effects I noted (if not eliminate them) but the same can be said for active preamps as well. 

It sounds as if we are not so far apart on what we want from a system.  Having heard some really great SET and Push-Pull triode Class A amps I can honestly say that I felt this Einstein system to have better dynamics and dynamic shading and more correct overall tone than amps I have heard using output transformers.  I think the output transformer is far from transparent and perhaps it is a coloration that you are used to and like very much?  I have daily exposure to the real thing (my girlfriend is a professional violinist who currently plays a stradivarius) and to me the OTL gets that character of live more correct, whereas even the best SETs I think now this bit of warmth that is usually present is due to output transformers (as well as a sense of slowing the pace a bit...but only a bit in the best amps).  Just like the passive preamp transformers have their sound character (ie. copper vs. silver, nickel vs. steel)  I would imagine the character of the output transformer is even greater (much more wire involved and bigger magnetic fluxes). 

Perhaps you are reacting to the fact that these amps are not SETs but push pull? 

I think if you have a very high sensitivity speaker with high impedance and can get away with 10 watts or less then a truly single ended OTL would be the way to go.   String up 8 6c33C tubes in parallel gives you 10 ohms output impedance and probably enough power (about 14 watts).  If you hook them up as a cathode follower maybe a little bit better.  I know that Transcendent Sound makes a SE OTL amp using the 6c19pi tube but he also uses a ton of feedback to bring down the output impedance.  I would rather use a more suitable tube and try to get away with no feedback or minimal if possible.  Have you heard such an amp before?  I have not but would be intensely curious about the sound.

11-04-2005 Post does not mapped to Knowledge Tree
morricab
Posts 51
Joined on 07-13-2005

Post #: 26
Post ID: 1657
Reply to: 1652
Re: a lightly a different subject: OTL

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I do have a speaker with a flat impedance.  It is an Apogee Caliper Signature with an impedance variation from 3 to about 4.5 ohms over the whole range.  Fortuneately it is not so dead as your example as it has about 86db sensitivity.  However, it is like an electrostat in that inspite of having a low voltage sensitivity it does not sound "dead" like a conventional box speaker of the same rated sensitivity.  This could be due to the moving mass of the drive elements or because thermal compression of the planar drivers is not a concern like it is for a normal low sensitivity cone.   I also have full range electrosats so here again is a design good for OTL.  High sensitivity horns (with moderately high impedances) should work very well indeed and I don't see again why they shouldn't be OTL friendly.  You have a similar problem with matching loads with a SET amp of moderate output impedance.  You will certainly get frequency response variations unless the same conditions are met.
11-04-2005 Post does not mapped to Knowledge Tree
Thorsten


United Kingdom
Posts 65
Joined on 12-06-2004

Post #: 27
Post ID: 1658
Reply to: 1656
Re: Better among worst?

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Hi,

 morricab wrote:
Thanks for the info about transformers.  It is as I expected, however, that these passive devices are not passive sonically at all. I agree with you that the higher quality of the transformers should lessen the effects I noted (if not eliminate them) but the same can be said for active preamps as well.


I agree. I have to note that even in active preamp I/We (the we are friends from the London Live DIY Circle) tend to prefer TVC's over resistors. An S&B TVC Input and S&B parallelfeed output transformer preamp adornes the system that contains the various "true OTL" PP Amplifiers (with 2A3, 300B and 845 units) which drive ESL pannels directly...

 morricab wrote:
I would imagine the character of the output transformer is even greater (much more wire involved and bigger magnetic fluxes). 


Maybe up to a degree, the key in a transformer are the so called "BH" curves. The result is that transformers are non-linear. A steelcored transformer with no magnetic bias distorts a lot. Add an airgap ana decent amount of magnetic bias and things become much more linear.

I cannot really say more, but I have a PP Amp (sorta commercial) that sounds to most that hear it a LOT like a really good SE Amp (and that from a high feedback EL34 class AB push pull design!).

 morricab wrote:
Perhaps you are reacting to the fact that these amps are not SETs but push pull?
 

Thats possible, hard to be sure. If I find the tyme (or is that parsley, sage Rosmarin & thyme) I want to try a SE OTL similar to what Bruce Rosenblit does, but with a single valve. Sadly my current drivers are 4R @ ~ 98db/W/m, definitly not SE OTL material.

 morricab wrote:
String up 8 6c33C tubes in parallel gives you 10 ohms output impedance and probably enough power (about 14 watts).
  

PARALLEL TUBES. Me no like way they sound.... ;-)

 morricab wrote:
Have you heard such an amp before?


Nope, I might look at using one of these "super 300B's" operated at low voltage and high current for the follower job. Maybe we can coax a watt out of 65 Watt anode dissipation?

On second thought, nah, I think I'll better get a Nickel Core Parallelfeed Output made for my upcomming 10Y Amp (3W out for 12W Anode dissipation)...

Ciao T ;-)


"It is to Madame Justice that I dedicate this concerto, in view of the holiday she seems to have taken from these parts." V
11-04-2005 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,540
Joined on 05-28-2004

Post #: 28
Post ID: 1660
Reply to: 1657
Re: Kill me, kill me, kill me!!!!

 morricab wrote:
I do have a speaker with a flat impedance.  It is an Apogee Caliper Signature with an impedance variation from 3 to about 4.5 ohms over the whole range.  Fortuneately it is not so dead as your example as it has about 86db sensitivity.  However, it is like an electrostat in that inspite of having a low voltage sensitivity it does not sound "dead" like a conventional box speaker of the same rated sensitivity.  This could be due to the moving mass of the drive elements or because thermal compression of the planar drivers is not a concern like it is for a normal low sensitivity cone.   I also have full range electrosats so here again is a design good for OTL.  High sensitivity horns (with moderately high impedances) should work very well indeed and I don't see again why they shouldn't be OTL friendly.  You have a similar problem with matching loads with a SET amp of moderate output impedance.  You will certainly get frequency response variations unless the same conditions are met.

Oh, morricab, way did you said that you are in the Ribbon would. They are tonally different speakers and any aspect of common sense are not applicable for then them. With the ribbons and electrosats you do need an amplifier but you need a super high voltage-pusher-machine that will be able to drive high capacitances, low mutuality and high believe that concept is more important then a result… :-)

Really, with electrosats- ribbons you do not need an OTL but you need a super OTL, or some kind of direct-couple 400W-500W monsters with 5-6kV on its plate. Really those amps could not be recognized as OTL class but rather as a self-contained direct coupled aberration uses a remedy for some very faulty loudspeakers.

Ok, now you do hate me…
:-)


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
11-05-2005 Post does not mapped to Knowledge Tree
morricab
Posts 51
Joined on 07-13-2005

Post #: 29
Post ID: 1667
Reply to: 1658
Re: Better among worst?

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Hi Thorsten,

"I agree. I have to note that even in active preamp I/We (the we are friends from the London Live DIY Circle) tend to prefer TVC's over resistors."

Hmmm....I guess I can't really see that unless you are enjoying a particular coloration you are getting from the TVC.   Afterall, as you mentioned the behavior of a transformer is non-linear whereas the behavior of a resistor (a good one) is linear, lower in distortion, and has no hysterisis (I think the same cannot be said for a transformer).  Resistors as a passive attenuator for sure lose dynamics but they don't affect the signal in the ways I heard from the TVC or the transformers in my Silvaweld preamp (which are good ones).  The Silvaweld, bTW, uses two 31 step silver attenuators with metal film resistors for level attenuation, the transformers are for balancing or unbalancing the incoming or outgoing signals when not using the XLR ins and outs, which bypass these transformers.

As I mentioned, I do not use the high quality nickel alloy transformers in my Silvaweld preamp precisely because I hear these colorations.  I have decided that even single ended sources are better off going through the balanced inputs, which do not use the transformers, than to use the transformers to convert the signal to balanced.  I also don't use them on the output.  I have found the XLR to RCA adaptors, while possibly coloring the sound, do much less to the sound than the transformers.  Now its not a bad sound, mind you, its a little warmer and softer sounding is all but through the balanced ins and outs there is extremely good clarity and low coloration from this preamp and from the rest of my system, which is perhaps why this coloration is so obvious.  With analog, I tried both (my DAC is balanced anyway) and found that I got a nice sound from using only the input or the output transformer.  Just a hint of the sound from the transformer, which with some recordings was nice.  Both transformers (in and out) was too much of this character and none was in the end the preferred setup.  For non critical sources (like my TV watching ) the unbalanced in is perfectly fine.

I have not heard too many parallel SETs but what I heard was pretty impressive. For example the New Audio Frontiers parallel SET 845 monoblocks are one of the very best amps I have heard.  Also, the Audio Note (kondo not UK) Kegon KSL is phenomenally good and is a parallel SET also.  Of course I have heard great SETs also.  I have heard great PP (Allen Wright's DPA300b being one of the best I have heard).  Yet I find the OTL sound to be less colored overall and more dynamic (especially in the microdynamic department.)

"I cannot really say more, but I have a PP Amp (sorta commercial) that sounds to most that hear it a LOT like a really good SE Amp (and that from a high feedback EL34 class AB push pull design!).
"
What is it?  Just curious maybe I have heard it or something close to it.
11-05-2005 Post does not mapped to Knowledge Tree
morricab
Posts 51
Joined on 07-13-2005

Post #: 30
Post ID: 1668
Reply to: 1660
Re: Kill me, kill me, kill me!!!!

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Well Romy, IMO they are not just tonally different they are more tonally correct, ie. they simply have less coloration than other technologies.  Just listen to a recording sometime made with a ribbon microphone and you will understand what I mean.

Since you don't "live" in this world I don't expect you to understand but my experiments with amps on my Apogees has shown that they work quite nicely with moderate power (in a moderate room of course).   This hybrid amp that Dmitri (I think that's who) made for example would work marvelously on them.   I have managed to get perfectly accpetable listening levels from them using a 20 watt SET amp.  Why?  three words. No thermal compression.  Also, being a line source, the sound level drops with distance more slowly than a point source.  So doubling of power really gives a true 3db increase in output.  Levels up to 95db are possible at 3.5 meteres with 20 watts.  The sound at 70db is still exquisite.  The truth is that the 18 watt Lamm ML2 in a moderate room size (say 20 square meters) would do the job and sound wonderful.  Perhaps you have never heard what it can do tonally??  Horns, regardless of how good, are always colored compared to a ribbon driver.   In addition, there is now a guy in Australia who will be making essentially an Apogee clone but with high efficiency ribbon drivers and should be getting horn like sensitivity (ie. > 95db/watt) without horns.  If you are not experienced with good ribbon designs I suggest you acquaint yourself (no Magnepan does not count).   In truth, I like the best horn designs I have heard...better than any conventional speaker.

I don't hate you for misguided ramblings.  Its like talking with a little precocious child Smile.  There is a reason microphones are either ribbon or electrostatic in nature.  Response linearity, senstivity to small signals, low coloration, uniformity of drive etc.   The speakers have the same advantages.  Again, there are good designs and not good designs but that doesn't mean the concept is flawed in fact it is the best concept but difficult to execute properly.
11-05-2005 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,540
Joined on 05-28-2004

Post #: 31
Post ID: 1669
Reply to: 1668
Re: ribbons/electrostats....

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 morricab wrote:
Well Romy, IMO they are not just tonally different they are more tonally correct, ie. they simply have less coloration than other technologies.  Just listen to a recording sometime made with a ribbon microphone and you will understand what I mean.

Since you don't "live" in this world I don't expect you to understand but my experiments with amps on my Apogees has shown that they work quite nicely with moderate power (in a moderate room of course).   This hybrid amp that Dmitri (I think that's who) made for example would work marvelously on them.   I have managed to get perfectly accpetable listening levels from them using a 20 watt SET amp.  Why?  three words. No thermal compression.  Also, being a line source, the sound level drops with distance more slowly than a point source.  So doubling of power really gives a true 3db increase in output.  Levels up to 95db are possible at 3.5 meteres with 20 watts.  The sound at 70db is still exquisite.  The truth is that the 18 watt Lamm ML2 in a moderate room size (say 20 square meters) would do the job and sound wonderful.  Perhaps you have never heard what it can do tonally??  Horns, regardless of how good, are always colored compared to a ribbon driver.   In addition, there is now a guy in Australia who will be making essentially an Apogee clone but with high efficiency ribbon drivers and should be getting horn like sensitivity (ie. > 95db/watt) without horns.  If you are not experienced with good ribbon designs I suggest you acquaint yourself (no Magnepan does not count).   In truth, I like the best horn designs I have heard...better than any conventional speaker.

I don't hate you for misguided ramblings.  Its like talking with a little precocious child Smile.  There is a reason microphones are either ribbon or electrostatic in nature.  Response linearity, senstivity to small signals, low coloration, uniformity of drive etc.   The speakers have the same advantages.  Again, there are good designs and not good designs but that doesn't mean the concept is flawed in fact it is the best concept but difficult to execute properly.

Morricab, believe me or not but I am familiar with what ribbon do and I agree that at under 70dB they sound somehow “interesting”. You see, then behind the interests there is something more…

You argue about ribbons lower distortions, bring irrelevant analogies with ribbon microphones, forget the mention then unavoidable front wave modification with any ribbon loudspeaker, compare ribbons with horns, avoid the subject of ribbons compression, mention the arguable subject of less coloration with ribbons and advocate the topology generally. Yes, any concept should be properly executed,  and I presume that you did it right: I will be glad to be invited in your listening room to learn.

However, there is a catch in all of this.

We in audio do not really prove to themselves or each other topologies or render the benefit of some given concepts. For me in audio, is very important my very much egotistic adequacy of my own experiences. For instance I experienced a certain event and felt how a certain attribute of my visions, me feelings, my personality and my own inner me reacted to this musical even. The event might be whatever it might be: live, recorded or broadcasted, the whole symphony of huts a minute musical phrase, juts a simple combination of two notes pronounces in a certain way…. All that I need from audio would be to reinstate the very same impact to myself when I would like to… there are always distortions…

Under the distortion I do not mean luck of harmonic linearity or anything else that might be quantifiable by a limited science but rather a deviation from the normal listing experiences that I have from the performed music. So how the ribbons/electrostats relate to all of it? The problem is that they do not relate. My “live” music, or the FM broadcasts, or my recordings experience might be closer or further from what I would like to get but the ribbons/electrostats experiences were always completely different, at least for me. When I listen the ribbons/electrostats I always instead of dealing with the music (or more precisely with my own reaction to music) I deals with my own alertness, trying to justify and convince myself that whatever I’m perceiving should be “good”. I mean with dynamic drivers I listen reproduced music “as is”, good Sound or bad, but I become MUCH easily gullible and credulous regarding to what I ma hearing. In contrary, with ribbons/electrostats I always internally extrapolate and interrupt sound into something ELSE and then, I listen that “abstractive something else”. To me, my experiences with ribbons/electrostats are similar with the experience of a bird dissecting when looking at the bird’s cut up wigs I’m wing trying to visualize a freedom of flying.

We defiantly might argue about the pure audio shortcoming of ribbons/electrostats (dynamic range, problems with complex music, disability to handle dynamic stress, killed lower frequency harmonics, tonal depressurization and many many others) but since I personally did not experience with ribbons/electrostats any noble musical listening sensations, and the direction that the ribbons/electrostats people took me before did not turn out to be fruitful, I do not think that I might be a very an attentive student to learn something about ribbons topology.

BTW, the amp the Dima designed was explicitly designed for a project (that went to nowhere) to drive the full range electrostats loaded into acoustic lenses. Dima clams that his amp feels very comfortable to drive 2uF capacitor….

Rgs,
Romy the Cat

PS: Do you think we need to start another thread? :-)




"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
11-07-2005 Post does not mapped to Knowledge Tree
Thorsten


United Kingdom
Posts 65
Joined on 12-06-2004

Post #: 32
Post ID: 1678
Reply to: 1667
Re: Better among worst?

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Hi,

 morricab wrote:
Hmmm....I guess I can't really see that unless you are enjoying a particular coloration you are getting from the TVC.
 

Nope. On this you are wrong. Based on direct bypass tests the TVC's I USE (that is the specific Items, not the genre) are MORE TRANSPARENT than a pair of good quality resistors, such as the Vishay Bulk Foils used in the AUdio Synthesis passion.

Luckily enough there are a number of reviews in existence now that compare the Music First Audio Passive Magnetic Preamp (a baby at whose birth I helped somewhat and yes, I use what is in effect the MK III spec of this myself, in copper I may add) to some of the best active and resistor based passive preamps. Others exist of devices by other makers using the retail versions of the same transformers (MFA uses a slightly different spec OEM unit). You may wish to peruse these various ones.

 morricab wrote:
Afterall, as you mentioned the behavior of a transformer is non-linear whereas the behavior of a resistor (a good one) is linear, lower in distortion, and has no hysterisis (I think the same cannot be said for a transformer). 
 

As it so happens, I was writing about specific products. But yes, transformers distort, it is a job for the designer to address this in his design. The S&B units do this by using a rather more linear than usual core material and loads of it (simple as that, honest, it is merely a question of cost). If you actually measure the distortion you will find that it is in the region of the noisefloor of most analysers and not materially differnet from the distortion measurable in resistor attenuators. 

FWIW, the TX-102 clocks in at < 0.0002% for the highest harmonic (3rd) @ 2V/1KHz with a 600 Ohm Source, THD stays basically flat down to around 100Hz at 5V (depends on level, at levels below 5V the "knee" slides down further in frequency and distortion is of course also lower), where it rises with a first order function.  

Other manufacturers may be unable to get the core material and cans S&B uses (simply because S&B paid for the tooling!!!!) and may even choose to use not just smaller core sizes but also inferior grades of core material (all the way doen to nasty generic steel) in order to lower their cost, whith obvious results on sound quality. As part of the development of the MFA units we had attempted to add some steel laminations to both increase level handling and give possibly a "better tone" Even just 10% of the whole core replaced by highest grade stell laminations resulted in an unacceptable loss of sound quality.

 morricab wrote:
Resistors as a passive attenuator for sure lose dynamics but they don't affect the signal in the ways I heard from the TVC or the transformers in my Silvaweld preamp (which are good ones). 
 

Sorry, but if the transformers in the Silvaweld preamp effect the sound as you say your conclusion that they are "good ones" may be erronous and driven by company propaganda and assumption, compared to actual fact.

 morricab wrote:
I have not heard too many parallel SETs but what I heard was pretty impressive. For example the New Audio Frontiers parallel SET 845 monoblocks are one of the very best amps I have heard.  Also, the Audio Note (kondo not UK) Kegon KSL is phenomenally good and is a parallel SET also.  Of course I have heard great SETs also.  I have heard great PP (Allen Wright's DPA300b being one of the best I have heard).  Yet I find the OTL sound to be less colored overall and more dynamic (especially in the microdynamic department.)
 

Of those that you mentioned I have heard the NAF Amp's and found them typhical "845" Amp's, terminating any point for me. I have had the chance to compare a wide range of Kondo (ANJ) Amplifiers in a friends system, note that these are pre KSL/BFA units. We had both early Wilson Watt/Puppies (3/2 IIRC) and Avant Garde Trio's as well as Gaku-On, Ongaku, Kegon, Baransu and Neiro there.

While all units shared a certain family sound, when driving speakers where the power levels where of no concern (trio's) the best of the lot was the Single 300B Baransu, with Ongaku second and Neiro third, then Kegon and Gaku-On. This was reversed on the WP's, where Gaku-On took the lead followed by Kegon, simply because the others run out of steam. But the PSE Amplifiers substantially lost imediacy and transparency to the (otherwise very much identical) SE units.

 morricab wrote:

 Thorsten wrote:
"I cannot really say more, but I have a PP Amp (sorta commercial) that sounds to most that hear it a LOT like a really good SE Amp (and that from a high feedback EL34 class AB push pull design!).

"
What is it?  Just curious maybe I have heard it or something close to it.


You have not heard it. It is a rebuild of the Shanling SP-80, only available in the UK and so far with only 6 Pairs made. I can say that is shares many of the principles embodied in the Harman Kardon Citation 2 Amplifier, plus some tricks of my onw, all of which combine to provide a PP Amplifier that has all the hallmarks of an SE Amplifier in terms of low level resolution, tonality and immediacy, while not loosing the advantages of the PP Principle, to wit large output power and low harmonic distortion at high power.

If a current commercial venture gets off the ground well you may very well see a further optimised (using the existing shanling chassis and iron limits the achievable quality somewhat) unit based on the same principles in wider circulation.

A review of a system including these Amplifiers (but really of a system in whose assembly I had more than a small influence and which included basically all my own designs/modifications except speakers) is here:

http://www.realhi-fi.com/pdf/hfcreview2.pdf

Ciao T


"It is to Madame Justice that I dedicate this concerto, in view of the holiday she seems to have taken from these parts." V
11-07-2005 Post does not mapped to Knowledge Tree
Thorsten


United Kingdom
Posts 65
Joined on 12-06-2004

Post #: 33
Post ID: 1679
Reply to: 1678
Some clarifications

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Folks,

A maker of Magnetics reading along has taken me privatly a little to task, it seems I was not clear enough with some of my statements, apologies.

First, I seemingly stated that Amorphous material was "always iron", that was not my intention, amorphous core material comes in many types, however the common one currently emplyed in the large Lundahl Transformers (there are indications that it also applies to their small signal AM transformers, but information is conflicting) and by Opera/DIYHFS is completely Iron based. As such the same BH curves apply fundamentally as they do for steel, what is different is the eddy losses etc.

I am also amused by certain claims that where made by a transformer maker that AM Cores eliminate the LF resonance between the transformers inductance and coupling capacitor, which is a claim I am commonly familiar as applying (not entierly accuratly BTW) to high nickel content permalloy/Radiometal/Mu-Metal et al, but never yet for ferrite and iron/steel cored devices....

Interresting alternatives to iron based AM would be Iron/Nickel/Cobalt (FENICO) Amorphous material, but it seems hard to get and carries an extreme premium over 80% Nickel Permalloy, which may not (or may be) be justified by a similar improvement in sound.... We keep investigating, sadly the demise of Telmag makes such investigation much more difficult for UK companies.

Secondly, my comments on the look of high Nickel content permalloy is based of course merely on my experience. The Hue of Nickel Permalloy is about that of the transformer cans in the picture of the Music First Passive Preamp on this page:

http://www.6moons.com/audioreviews/bo05/srajan.html

I have not yet seen any high nickel permalloy looking significantly different.

Ciao T


"It is to Madame Justice that I dedicate this concerto, in view of the holiday she seems to have taken from these parts." V
11-07-2005 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,540
Joined on 05-28-2004

Post #: 34
Post ID: 1681
Reply to: 1679
Very HF and amorphous materials?

T,

I would like to ask you a question. Understanding that amorphous core material comes in many types still, if to generalize it them might I propose an observation that beside all amorphous sonic and technical advantage (presumably they exist) the amorphous core transformers have some sonic idiosyncrasies.

It hard to explain was it is and practically for me who is not familiar with relationship between the core materials and sound of the materials. Still, I know how it should sound and my observations that the amorphous core in some way very-very-very-very-very-very slightly depersonalize the HF. I would put in this way: if I build a 10-channel amp then I would defiantly use the amorphous core for MF channel and for mid FH channel. However, for the higher HF channel I would go for a super low inductance none-amorphous. What I feel that amorphous core make sound “strong” and “muscular” that is not what I want at the highest frequencies. Do not confuse it with the crappy silver sound or anything else: amorphous is problem free tonally. I ‘m talking about rather the “overconfident virility” at the highest frequencies then about some kind of “audio” problems.

Perhaps the amorphous core magnetic that works at the very HF should be load differently? For instance the transformer that work at the very HF should loaded much harder than it typically would? Perhaps it would bring out some “overly-richer harmonic content” and might slightly “soften up” the amorphous transformers?

T, would you elaborate on it if you feel that it has any merit?

Rgs,
Romy the Cat


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
11-07-2005 Post does not mapped to Knowledge Tree
Thorsten


United Kingdom
Posts 65
Joined on 12-06-2004

Post #: 35
Post ID: 1682
Reply to: 1681
Re: Very HF and amorphous materials?

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Hi,

 Romy the Cat wrote:
T, would you elaborate on it if you feel that it has any merit?


Really, I do not know. From my limited experience I have found that multiway active systems are very much a tuning excercise par excellance. Given that all these multiple drivers have distinctly sonic signatures it is usually hard to achieve coherence. Using different Amplifiers can be used to get the combined tonality back to "neutral" or to wherever it is supposed to be, but it means optimising together each Amplifier/Driver combo.

Often however it is very difficult to achieve these complementary colorations and thus often coherence is lost further, rather than being regained. Hence often completely identical amplifiers for all channels (or at least as identical as possible) seem to hold things better together.

With my friends big 2-Way electrostatics (they cover 120Hz-5KHz in one panel and above 5KHz in another) we found that topologically similar amplifiers with similar parts and simple passive RLC crossovers and equalisers gave best coherence. Add an amplifier with greatly different parts or topology and the music plays different tunes.

In that case BTW the drivers for HF and LF are very similar, use identical construction methodes and materials and only size of surface and airgap as well suspension is varied to optimise each ESL panel for the intended frequency range.

Much rambling and very little information, sorry, but maybe it helps.

Ciao T


"It is to Madame Justice that I dedicate this concerto, in view of the holiday she seems to have taken from these parts." V
11-07-2005 Post does not mapped to Knowledge Tree
morricab
Posts 51
Joined on 07-13-2005

Post #: 36
Post ID: 1683
Reply to: 1678
Re: Better among worst?

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As to the best transformers souding more transparent than the best resistors, I'll believe it when I (don't?) hear it.  You claim to have heard this but I most certainly haven't.  Based on theoretical arguments the noninductive metal film resistor is certainly more linear and less frequency dependent of the two devices.  That being said, I AM open to hearing a better transformer based passive using the S&B transformers.  If they best my active then so be it, I get a passive and save money Smile.

I am not so sure the NAF amp has a typical 845 sound (I have heard only a couple of others that were handily outperformed by the NAF with not nearly its openness and speed) but perhaps it has a sound that is a function of the type and size transformers that are required for such an output tube?? Perhaps the "family" sound that one hears from the Audio Note amps is due to the use of their proprietary silver transformers?  Again then we would be back to the sound of the transformer affecting the overall "character" of the amp.  Another possible reason you don't like parallel SET amps is because the demands on the output transformer are much greater and saturation a more likely problem.  Bigger iron= bigger problems, no? Again if this is part of the problem we are back to the output transformer again. 

Personally, I like what Wyetech labs does for their big Topaz when used as a monoblock.  Each tube gets its own output transformer (same as the SET stereo version) instead of using one larger transformer for both paralleled tubes.  Another really good one I heard that was paralleled was the Ayon (formerly Vaic) 52b reference monos.  I think they also use a separate output transformer for each paralleled tube. 

As to the Silvaweld input and output transformers:  You may be right but their literature says they are using high quality nickel alloy transformers.  It is not more specific but clearly they are not using all steel cored transformers.  If I replaced them with S&B line input and output transformers maybe it would be better.  I still doubt it would be better than no transformers.  If you look at the design and parts used they did not cut corners on this design so I find it hard to believe they stuck just any old transformer in there.  However, I am sure there are better ones available.

Interesting that you are so enamoured with a moded EL34 based amp.  I imagine it is possible, with proper attention to make a spectacular sounding amp with these tubes and the push-pull concept.  Tell me are you using it as a triode or are you still going "ultralinear"?
11-07-2005 Post does not mapped to Knowledge Tree
Thorsten


United Kingdom
Posts 65
Joined on 12-06-2004

Post #: 37
Post ID: 1684
Reply to: 1683
Re: Better among worst?
Hi,

 morricab wrote:
As to the best transformers souding more transparent than the best resistors, I'll believe it when I (don't?) hear it.  You claim to have heard this but I most certainly haven't. 

 
Well, the claim is not just mine.

Martin Colloms compared the Music First Audio Passive Magnetic Preamp to a Vishay Resistor version of the Audio Synthesis "Passion". He commented along these lines:

"More sense of drama and dynamic expression"
"Firmer and deeper bass"
"Impression of more detail"
"more delicatly subtle and transparent"
"not quiet as open and perfectly neutral as the passion"

while he noticed the passion had:

"slightly larger stereo images"

(maybe blown up stereo image as sometimes notable with Vishay Bulk foil resistors, also maybe the "look here how great I sound" obnoxious pushing forward of detail the vishay resistors do account for that? I agree with the relative assessment BTW, but personally have slightly different weighting on the impressions)

He also noted much less variability of the MFA PMP with cables and sources, compared to the Vishay Passion. He scored the MFA PMP slightly higher than the Passion (36 vs. 33) on his highly arbitrary scale, but in a region where only very little gear ever makes it.

At any extent, the hundert series transformers from S&B derive from the 101 whch was designed to be as close to a straight wire in terms of measured and subjective performance as was possible. The subsequent 102 & 103 have shown that in most applications they live up to this "close to a piece of wire" aim, even if they still fall slightly short. Other manufacturers of transformers may not have this goal of "nothing but the music" in mind while designing, voicing and making their products.

 morricab wrote:
Based on theoretical arguments the noninductive metal film resistor is certainly more linear and less frequency dependent of the two devices. 


Maybe, I will readily argue that once a system is considered this may nevertheless turn out the opposite way. The MK II version of the TX-102 had a completely unneccarily wide bandwidth for audio (measured flat up to 3MHz, there the generator ends, we suspect 10MHz+ would have been on the cards) which showed up as a problem when coupled with much gear, the current MK III has been designed as a deliberate bandpass device with 10Hz-40KHz ruler flat (remember the rule of the 400000). 

A resistor attenuator BTW shows a LOT MORE variability with setting and load capacitance where frequency response is concerened, so one may argue that a resistor attenuator is in fact the by far more frequency dependent device!!!

 morricab wrote:
I am not so sure the NAF amp has a typical 845 sound (I have heard only a couple of others that were handily outperformed by the NAF with not nearly its openness and speed) but perhaps it has a sound that is a function of the type and size transformers that are required for such an output tube??


I routinely find myself prefering the 211 over the 845 among the "big" triodes. I think it is more down to a mixture of the anode curves of the 211 vs. 845 (the 211 seems to have less variability of Mu with signal levels) and the much lower bias voltage of the 211 which means it is easier to make a linear driver stage.

In terms of output transformer size and design there is not much to choose between 211 & 845, except the 211 really needs well above 10KOhm load impedance while the 845 manages with 5-6k which is what is often used.

 morricab wrote:
Perhaps the "family" sound that one hears from the Audio Note amps is due to the use of their proprietary silver transformers? 


Maybe, but the "Kondo Sound" is still there in the copper transformer versions. I think it has more to do with the valves and circuits used, plus a few tricks not normally illustrated in the schematics that are in public domain. I find it interesting that the "Kondo Sound" is pretty consitent across preamplifiers and also between Push-Pull and SE Amplifiers from Kondo.

 morricab wrote:
Again then we would be back to the sound of the transformer affecting the overall "character" of the amp.


You need to realise that the physically larger a Transformer becomes the narrower the available bandwidth for a given construction. Due to the need to handle a lot of "magnetic bias" SE Output transformers become very large, physically, and have invariably problems on one or the other (or both) ends of the spectrum, even if extreme measures are taken. Transformers problems expand expeonentially as size goes up. However, this means comparably small line level devices (or MC level ones) can be made to levels of perfection that appear incredible in the light of the performance of generic tube amp output transformers. 

 morricab wrote:
As to the Silvaweld input and output transformers:  You may be right but their literature says they are using high quality nickel alloy transformers.


That may be so. However my experience is that truely broadcast level quality (in the definition of the german radio/tv networks) transformers are sonically very transparent. If you find the transformers used not transparent to an EXTREMELY HIGH degree, then I must suggest that in the terms I subscribe to they are not "broadcast quality", which to me translates to "Pro" or "High Quality". This may be of course entierly intentional on the part of the manufacturer, who in fact may feel a certain addition/subtraction from neutrality desirable. Past that Nickel Alloy comes in a wide range of mixtures, from 5% to > 78% Nickel. Formal designations for these Mixtures vary, "Permalloy" and "Radiometal" are generally the lower nickel content designation, with "Superpermalloy" and "Mu-Metal" being the designations for high nickel content alloys, but the use is not consistent, as these old expired tradenames and not formal designations.

 morricab wrote:
I still doubt it would be better than no transformers.


I do not believe in adding transformers for adding a transformer's sake. However, I do feel that there are specific applications where a well designed transformer is a preferable solution.

 morricab wrote:
If you look at the design and parts used they did not cut corners on this design so I find it hard to believe they stuck just any old transformer in there.


Well, the OEM pricing of a pair of "onehundert series" S&B Transformers is several 100% that of anything seemingly comparable based on standard cans and lams. At this point very few OEM's use them and virtually only use them for passive preamplifiers in the form of the 102, with only three users of any other of the 100's and Msuic First being one of them. The reasons are cost and size, most potential OEM customers (including some that make VERY expensive equipment) find the cost too much for their accountants to put up with.

 morricab wrote:
Interesting that you are so enamoured with a moded EL34 based amp.


I am not enmoured and to call it "modded" is being modest. It is in effect a groundup re-build that retains only the key mechanical components. I tend to prefer the Amplifier BTW with KT-88's fitted, but at home keep SE Amp's (as I have them ;-) ).

 morricab wrote:
I imagine it is possible, with proper attention to make a spectacular sounding amp with these tubes and the push-pull concept.  Tell me are you using it as a triode or are you still going "ultralinear"?


The Amplifier is switchable Pentode, Ultralinear or Triode, Class Ab1 operation with class A to around 2 Watt. While triode operation sound marginally better, the differences are quite small. This is attained simply by using tons of negative feedback, which normally is a no-no. But the old Citation Gear had actually found a way to apply this without the usual sonic problems, something which worked out well.

Together with some other tricks (including arguably at least one or two swiped from Kondo and another one or two abstracted from Ken Shindo - not much original work in there I must admit) I managed to design/construct a high feedback PP Amplifier with good compatibility to normal speakers (when compared to a 2A3 or 45 SE Amplifier) while retaining what at least to me makes SE sound so attratcive, that is the purity, immediacy and lack of a feel of mechanism in the music reproduction.

Most funny is that even in pentode mode for the output stage this Amp sounded more "SET" then my IT coupled zero feedback push-pull DHT amplifier (the IT was a high nickel S&B prototype), sounding more direct and immediate and harmonically more complete.

Anyway, it was a fun challenge to make it work like that.

Ciao T


"It is to Madame Justice that I dedicate this concerto, in view of the holiday she seems to have taken from these parts." V
11-08-2005 Post does not mapped to Knowledge Tree
morricab
Posts 51
Joined on 07-13-2005

Post #: 38
Post ID: 1694
Reply to: 1684
Re: Better among worst?
"You need to realise that the physically larger a Transformer becomes the narrower the available bandwidth for a given construction. Due to the need to handle a lot of "magnetic bias" SE Output transformers become very large, physically, and have invariably problems on one or the other (or both) ends of the spectrum, even if extreme measures are taken. Transformers problems expand expeonentially as size goes up. However, this means comparably small line level devices (or MC level ones) can be made to levels of perfection that appear incredible in the light of the performance of generic tube amp output transformers."

That is exactly my point as to maybe why you don't think parallel SET amps sound so good.  They need even bigger/higher power transformers, which gives rise to the problems you have mentioned.  Check out the Wyetech Topaz amp and in its mono form it was using two smaller (though still pretty big) output transformers and combining the signal in parallel after the transformers. Now I see that their latest version of the amp has gone away from the Svetlana 572-10 tube and back to the 211.  For one thing the 572-10 is no longer in production but seems to be a very good sounding "big" triode (it is actually quite small for its rated dissipation) (the Viva Aurora used to use this tube also (but maybe the 572-3 type) and sounded very good as well).  It is interesting that this designer prefers the 211, maybe for the reasons you have said. 

"Well, the OEM pricing of a pair of "onehundert series" S&B Transformers is several 100% that of anything seemingly comparable based on standard cans and lams."

You may be right.  It would perhaps be worthwhile to look into "better" transformers but I am not sure that an advantage can be found over just going RCA to XLR adaptor into the balanced inputs and thereby bypassing the transformer altogether.  What do you think?
11-08-2005 Post mapped to one branch of Knowledge Tree
Thorsten


United Kingdom
Posts 65
Joined on 12-06-2004

Post #: 39
Post ID: 1702
Reply to: 1694
Re: Better among worst?
Hi,

 morricab wrote:
You may be right.  It would perhaps be worthwhile to look into "better" transformers but I am not sure that an advantage can be found over just going RCA to XLR adaptor into the balanced inputs and thereby bypassing the transformer altogether.  What do you think?


I think that a transformer needs an actual reason for being used instead of a piece of wire.

At the very best the transformer can approach the piece of wire closely, very closely indeed, it cannot really improve on the piece of wire, though it may resolve other problems elsewhere in ways the wire could not and lead thusly to improved sound.

But usually, if you can use a piece of wire use it.

If you need a transformer or perhaps another device whose function could be gainfully substituted by a transformer (example - linestage with cathode follower and feedback vs. the same linestage valve without follower and feedback and using a parallelefeed stepdown linetransformer to lower gain and output impedance) the transformer may be the better choice.

For example, you may be interrested to build a copy of the "final euridice" linestage to see if can outperform the silvaweld.

The advantages are that you have Balanced or SE inputs and outputs any which way you like, around 20db very linear gain and around 150 Ohm output Impedance and loads  of available output Voltage (certainly +14dbu @ 20Hz for the TX-101, likely more with the more recent upgraded core materials - that is around 4V @ 20Hz) with negligable distortion.

MY PERSONAL current realisation (where I to build one) would look like this:

1) S&B TX-102 as volume control, with suitable switch

2) 2V Lithium Battery negative pole to the grid of the Valve, bypassed with good non-magnetic silver mica capacitor and in series with a small, low q retardation coil, here for killing oscillation

3) C3g (it is currently "best sound for money" in the application) postal pentode wired as triode, many alternatives exist, the russian 6S3, 6S4, 6S45, 6E5 triode wired, EC8010, EC8020, E55L triode wired, E180F triode wired, WE 417A, WE 437A, 3A/167M and so on....

4) Anode load inductor for C3g, I would use the S&B 120H/12mA 40% Nickel item

5) Mundorf Silver (or other to taste) Parallelfeed Capacitor 3.9uF

6) S&B TX-101 MKII as parallelefeed output transformer, wired for 4:1 stepdown

7) Valve rectified (GZ34/37) and Valve Regulated (O2A X 2, EF86 X 2, 6AS7) powersupply, around 130V @ 12mA X 2 for both Channels, AC for C3g heaters. The +B is besically adjusted for around 10 - 12mA current through the linestage valve.

I am not going to make any claims like "takes the Lamb to the slaughter" or "takes all the nine lives of the CAT" or "Cuts off Conrad's Johnson" (though I believe the Music First Passive Preamp did something like that at the recent HiFi News Awards to the nearly ten times as expensive CJ ACT II) and so on.

But it is a most excellent linestage and what I would choose, IF I needed a linestage with gain, which I don't and which is why I use a copper TX-102 based passive line stage.

Ciao T


"It is to Madame Justice that I dedicate this concerto, in view of the holiday she seems to have taken from these parts." V
11-08-2005 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,540
Joined on 05-28-2004

Post #: 40
Post ID: 1704
Reply to: 1702
Thorsten's preamp idea

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 Thorsten wrote:

MY PERSONAL current realisation (where I to build one) would look like this:

1) S&B TX-102 as volume control, with suitable switch

2) 2V Lithium Battery negative pole to the grid of the Valve, bypassed with good non-magnetic silver mica capacitor and in series with a small, low q retardation coil, here for killing oscillation

3) C3g (it is currently "best sound for money" in the application) postal pentode wired as triode, many alternatives exist, the russian 6S3, 6S4, 6S45, 6E5 triode wired, EC8010, EC8020, E55L triode wired, E180F triode wired, WE 417A, WE 437A, 3A/167M and so on....

4) Anode load inductor for C3g, I would use the S&B 120H/12mA 40% Nickel item

5) Mundorf Silver (or other to taste) Parallelfeed Capacitor 3.9uF

6) S&B TX-101 MKII as parallelefeed output transformer, wired for 4:1 stepdown

7) Valve rectified (GZ34/37) and Valve Regulated (O2A X 2, EF86 X 2, 6AS7) powersupply, around 130V @ 12mA X 2 for both Channels, AC for C3g heaters. The +B is besically adjusted for around 10 - 12mA current through the linestage valve.

Very interesting, Thorsten!!!

May I ask you, this realization of yours… dose it has any own “sound”. My point is that if you plug this hypothetical unit right at the input stage of you power amp (not at the out stage of your front end) then what contribution of that “realization preamp” you would find be acceptable and what you feel would not be? You see, I have my “feeling” that it is hardly possible to make any tube-based completely transparent line-level buffer. Whoever engineers I asked, including my own very amateurish attempts, everyone suggest me that it is imposable.  Perhaps it was juts my experience… Anyhow did you look at the SS world for the “ultimate buffers”?

Rgs,
Romy the Cat


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
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