| Search | Login/Register
   Home » Melquiades Amplifier » 6 Channel Version of Super Melquiades (132 posts, 7 pages)
  Print Thread | 1st Post |  
Page 3 of 7 (132 items) Select Pages:  « 1 2 3 4 5 » ... Last »
   Target    Threads for related reading   Most recent post in related threads   Forum  Replies   Views   Started 
  »  New  Super Melquiades Amplifier...  About the Super Melquiades Bass....  Melquiades Amplifier  Forum     29  187734  07-16-2005
  »  New  Fun with transformers?..  Re: An amplifier is not a subject but a service.....  Melquiades Amplifier  Forum     7  66025  10-21-2005
  »  New  Building Melquiades: Chronicle of full-range..  VR2 issue leading to jump in current on 6C33 tube...  Melquiades Amplifier  Forum     44  253241  06-09-2006
  »  New  5 Channel Version of Melquiades..  Very easy....  Melquiades Amplifier  Forum     21  168587  07-23-2006
  »  New  RAAL “Water Drop” tweeter for Macondo...  Your comment takes me by surprise...  Horn-Loaded Speakers Forum     77  673569  02-16-2007
  »  New  The one-stage Melquiades...  Tubes vs. Speakers vs. FR...  Melquiades Amplifier  Forum     73  463769  04-21-2007
  »  New  The single-stage Milq and power Supplies...  Just the tank...  Melquiades Amplifier  Forum     10  64604  05-03-2007
  »  New  A DSET is better then an expensive SET..  DIY Stradivarius...  Audio For Dummies ™  Forum     41  252885  09-21-2007
  »  New  Amplification and Consciousness...  Freedom of expression vs. something to say...  Playback Listening  Forum     15  75390  01-07-2008
  »  New  My (Amplification + Acoustic System): what is next?..  Macondo and Melquiades in the NEW room....  Audio Discussions  Forum     41  206333  01-10-2008
  »  New  All Active! A DSET and multi-way acoustic system...  Hahaha...  Audio Discussions  Forum     14  81121  01-31-2008
  »  New  The Melquiades' "Remote Biasing"..  The Melquiades' "Remote Biasing"...  Melquiades Amplifier  Forum     0  14695  02-05-2008
  »  New  A proper implementation of low-pass filters..  Low Pass...  Melquiades Amplifier  Forum     4  33692  02-18-2008
  »  New  Incorporating active crossovers into DSET..  Thanks...  Melquiades Amplifier  Forum     2  30305  07-22-2008
  »  New  Single-stage Melquiades vs. DHT amps..  A hallucination?...  Melquiades Amplifier  Forum     397  2590031  11-22-2008
  »  New  If you’re multiamping then use passive-line lever cross..  Crossover and DSET?...  Audio For Dummies ™  Forum     3  37093  01-21-2009
  »  New  The DSET perspective examines the Herb Reichert article..  Are you still in Reutlingen, Germany?...  Melquiades Amplifier  Forum     5  68064  07-01-2009
  »  New  Training amplifiers..  The Milq's demands for burning...  Melquiades Amplifier  Forum     16  81446  03-20-2006
  »  New  Think ahead how to measure the DSETs gain...  The calibration mode is for DSETs not for SET....  Audio For Dummies ™  Forum     2  18942  09-17-2009
  »  New  Amplifiers heat… a real-estate solution?..  I have seen this simular concept...  Melquiades Amplifier  Forum     1  15392  09-18-2009
  »  New  About DSET-driven multi-way acoustic system maintenance..  About DSET-driven multi-way acoustic system maintenance...  Horn-Loaded Speakers Forum     0  18125  11-01-2009
  »  New  Thomas Mayer’s Triamp..  It is much more then juts "properly calculated and...  Melquiades Amplifier  Forum     2  25758  03-03-2010
09-20-2007 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,543
Joined on 05-28-2004

Post #: 41
Post ID: 5336
Reply to: 5329
The singe-stage, the S2, the RL filter and the … Alleluia.

One of the most interesting outcomes of the Milq conversion into 6 channels is the impact it had to it MF channel.  The tweeter is a separate subject, I still work on it, I know how it will be done but I did not hear the final result. I would like to report something special about fundamental channel but there is nothing special about it – it sounds as it was before. I have with the dedicated amplifier some flexibility to play with it but basically it the same. The upper bass not has own dedicate amp with 14dB superfluous gain and I can theoretically to put in there any driver I wish, not necessarily as crazy sensitive as Fane was. I might do it in future if I find more interesting sounding driver then 8M. However, the sound of MF did change quite interestingly.

If you read above then you know that my primary concern was the inappropriate harmonic changes with volume when a channel was high-passed and with opened top. After many experiments I summarized that it was related somehow to the filtering capacitor.  Not necessarily a capacitor as a “better or worst sounding capacitor” but rather a capacitor as a topological entity. A serial filtering  capacitor is not coupling of power supply capacitor and it is not charged by DC, therefore it’s dialectic is not polarized and it gets re-polarized with every electron of AC signal. It usually impacts sound statically, injecting permanent  coloration, and I never seen before that it had dynamic impacts fluctuating with volume. The Air cap was better solution it had no re-polarizing dialectic. However, the RL fitter was juts way out there. It immediately did not just answer all questions but make the question do not need to be asked.

The S2 driver with the RL filter sounds exactly how it sound without any filter at all, in fact it sounds slightly better then without any filter. Perhaps it has to do with unloading bass from inductance-challenged transformer but I did not hear any distortions what I drove the 4H MF transformer full-range. So what is so special with the sound of the new S2 channel? Here are a few factors:

1) Less “bad granularity” without loosing of the “good granularity”.

2) Way cleaner upper region, though without the “bad granularity” it might feel in beginning that it has “less HF extension”

3) The awareness of the driver about the full range or something that I call the “neighborhood watch effect”.

This last entry should be explained because it was EXACTLY what I was looking to get from my MF driver. When I listen my stand alone S2 now it reproduces above 1K but it has awareness about the whole spectra of music. It is not the bottom knew response and but rather some very long acoustic-like harmonics that make the driver to reacts upon the events that are outside of it reproducible range. If I have a bass note that shell not be auditable via the MF channel then this note of course is not auditable but the MF channel still creates a “perceptional event” that indicates that there is a hole in the music that should be filed with sound or with mental extrapolation.  The channel with capacitive filter does not do it – it masks out events from the non-reproduced regions. The driver in the way acts as a pointer that shows off what the others channels shell be and how they shell sound. Of course it is necessary do not subtract from it the S2 it’s speed, the phenomenal transient capacity, the “absolute tone” and the vintage ability “to go boiled” with tone when it necessary.  Hey, if the second channel will do the same then it looks like I will be able to play the brutal London Symphony’s valve trumpets and soprano trombones as they should be played…

I am becoming a more satisfied Pussy with my 6-chennal DSET project…

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
09-20-2007 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,156
Joined on 10-12-2006

Post #: 42
Post ID: 5337
Reply to: 5336
I LOVE #3!
#3 reminds me of the HF-only naked ribbon, which seems to be the only exception, able to do this through a series cap.

If you have the Mercury SR2-9013 35mm master Dorati/LSO Nutcracker, that might be a treat (if you can still do the Nutcracker, of course...).  There are other LSO performances in this particular Living Presence series, however, and I think maybe Firebird (if you can still do the Firebird...).  In fact, they might all be "war horses"...

Now, how to get 180 phase and 12 dB slope without a cap...

BTW, the electrolytics proved totally worthless for X-os; even the Solens are worlds better.

Who knows how many times the signal can be "re-constituted" via inductors?  I am just thinking out loud here, but it may be that the inductor is in the end not a lot more problematic than so much straight wire; maybe less...

Best regards,
Paul S
09-20-2007 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,543
Joined on 05-28-2004

Post #: 43
Post ID: 5338
Reply to: 5337
It is the way how I see it…

 Paul S wrote:
If you have the Mercury SR2-9013 35mm master Dorati/LSO Nutcracker, that might be a treat

Hate that performance.  Dorati did not play Tchaikovsky appropriately. Each and single Dorati’s Tchaikovsky piece sound to me like a shopping in IKEA…

 Paul S wrote:
Now, how to get 180 phase and 12 dB slope without a cap...

I do not think it is necessary with tweeters as the job of the tweeter is to inject nose not sound, unless the tweeter crossed too low, and in such case the selection of a ribbon tweeter was a mistake most likely.

 Paul S wrote:
Who knows how many times the signal can be "re-constituted" via inductors? 

I do not think that any re-constitution takes place. In a cap the signal that is in the filter zone of transparency flows still on the capacitance of the devise – it has no physical contact between input and output and the cap acts s a frequency depended series regulator. An inductor, however, acts as a shunt regulator, shorting the frequencies and the band-path of the RL filter flows directly hardwired to the load.

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
09-21-2007 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,543
Joined on 05-28-2004

Post #: 44
Post ID: 5340
Reply to: 5336
Listening the New Super Milq: the first impressions.

Last nigh I spend a couple hours to listening this thing. Since the amp is done in design phase and the final parts are still in order I can not finish it and close up – it kind of frustrating… Still, it gives opportunities to listen it knowing that it’ll be “like that” when it will be done.

I have right channel that is absolutely untouched old 3-chennal Melquiades with “old” Macondo. As the left channel I have the new 6-chennal Melq coupled with the new Macondo. Of course I feed them with the same mono signal and it gives a very good illustration where I have gone in term of Sound with the 6-chennal Melq revision.

As I said before the flexibility to write any sound I wish with 6 active channels is very appealing. Also, as I said before the top 2 channels on the new Milq/Macondo are the most interesting.

To best describe what the new MF channel does would be to imagine paintings that were painted by brushes of 8mm and 1mm. The narrower brash allow going into greater amount of details, if there is a need for it. Sonically it works very interesting as the channel goes into details not always but only when music calls to it. When it necessary it still paints the picture of Sound with the sweeping stoke of the large brash. Ah, the wonder of the 6E6P!!! What is very important to understand is that this new higher level of “resolution” has nothing to do with the idiotic illusion of hyper-resolution, escorted with harmonic castration, as the most of the nowadays manufacturers do (Kharma/Avalon/Magico and many other). Quite in contrary - the new Milq/Macondo MF channel has more dominant low order harmonic tail then the old MF channel, the tail that stays with volume. At the very same time the driver despite of the long harmonic tail runs across the dynamic range even faster then before.  Quite a positive result! What is also is very important to understand that the new higher level of “resolution” has also absolutely no Spectral-like HF dithering where the upper range hyper-structuralism is perceived by audio-Morons™ as  “quality”. The new MF channel goes up very forcefully but very pliable with grace and elegance. When the channel hits it’s limit (dynamic or response) it does not dive in convulsions but just crumbles with modishness and without calling to itself. It is in way reminds me the sonic fading of my channel armed with electromagnetic S2 driver but the new MF channel fades from the Sonic heights that the electromagnetic never ever approached.

The HF channel with the new Milq is completely different story and they are a totally new page of HF evolution compare to what I had before. I do not think I even heard that type of HF. It will be a separate set of the observations in the “Water Drop” thread when I feel I am ready.

I was playing Bach’s harpsichord concertos last nigh and I come to a very interesting observation that my Injection channel works quite different with new Super Milq then it was with old Super Milq. I was driving the old Macondo from the amp of the new Super Milq and confirmed that it was not because the differences in amplification. The new Milq/Macondo has subjectively higher dynamic range and height level of tonal saturation. That makes the colorizing-dithering effects of Injection less beneficial with the new Milq/Macondo. I still see the Injection benefits but I apply it now much more conservative then before – a very positive thing from my point of view. The good thing also is that the new Milq/Macondo’s in it’s new level of tonal saturation do not dive into the “Van Gogh colors” as my Injection Channel with Reds tends to do…

It looks like the new Super Milq/Macondo idea turns into something very interesting. I really would like see it all done and the amp is closed up and permanently installed. In reality I certainly do not know what is responsible for the positive upper range advancements in the new Milq/Macondo tandem. It might be the elimination of high capacitive 6C33C, it might be the use of the single stage amp, it might be the use of different output transformers, it might be the use the small topological changes that were made in there, it might be the use of different type of filters, it might be the use of different rectifiers and some other changes in PS section. If I were in audio business then I would catalog the changes and try to capitalize on them but since the success in audio for me is Sound in my listening room then I less care about the reasons of the result if the results are satisfying.

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
09-22-2007 Post does not mapped to Knowledge Tree
jessie.dazzle


Paris, France
Posts 456
Joined on 04-23-2006

Post #: 45
Post ID: 5353
Reply to: 5340
Build process : DSET
Ok, you have definitely earned a Cohiba break!

While reading of your progress on the 6 channel amp, I was thinking ahead, and how I might approach the building of such amps as separate projects for each frequency band (separated physically as well). In my particular case, this would be in the interest of keeping things simple, but also to leave the ML2s to run the rest of the system while building/evolving the new amps. The idea being to remove the ML2s one frequency band at a time, and compare one addition (one frequency band) at a time against the ML2s.

But I'm getting way ahead of myself... still much to do on the horns.

I wish you strength power and courage in creating the second amp!

jd*



How to short-circuit evolution: Enshrine mediocrity.
09-23-2007 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,543
Joined on 05-28-2004

Post #: 46
Post ID: 5363
Reply to: 5353
My view on the DSET built process.

 jessie.dazzle wrote:
While reading of your progress on the 6 channel amp, I was thinking ahead, and how I might approach the building of such amps as separate projects for each frequency band (separated physically as well). In my particular case, this would be in the interest of keeping things simple, but also to leave the ML2s to run the rest of the system while building/evolving the new amps. The idea being to remove the ML2s one frequency band at a time, and compare one addition (one frequency band) at a time against the ML2s.

Well, I understand what you are trying to do but I see some problems with this approach. I the way how you approach it you will not have optimized paths for input stage and very much might end up with 6 input cables. Alternately it might be done as 6 plug-in sections, using high quietly Tektronix knife-connectors… If so then the PS and everything else should be packaged with plug-in objectives.

If I have an aim to build an unknown DSET for myself then, knowing what I know now, I would chose for following approach:

1) Build one prototype of full-range SET channel, powering it from any old good lab power supply. If you do not have it then get on eBay for $200-$300

2) Deeside for yourself if the amplifier is worth pursue and delivers the results that I would like to see (sound, power, gain, measurements, stability, operation, parts etc…)

3) Built a power supply for whole DSET, calculating the power for 6 channels (with 30%-50% spare power) and use multiple taps (100%, 110%, 120%, 130%, and 140% on primary for plate transformers, enabling me to add channels to this supply. Do not under-estimate the thoughts about the PS to amp interface – it is VERY important decision.

4) Convert the built full-range channel into a first DSET for upperbass/lover-Mid channel powering it from the DSET power supply.

5) Order the output transformers for the rest channels and having thier dimensions begin to think how the whole DSET will be package chassis/chassiss – wise, fitters-wise, layout-wise etc…

Rgs, 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
09-23-2007 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,543
Joined on 05-28-2004

Post #: 47
Post ID: 5384
Reply to: 5249
The biggest bang for a back.
The amps is not ready yet but starting to use it as it I have to tell you that there is one feature that make me so ecstatic that it even shame to admit. I am talking about a pedal remote control. It sounds like not a big deal but it is amazingly comfortable and it cost noting to implement – just one high-power latching relay. Since practically everything in my system is on all time then to turn the playback on is juts about hitting the pedal with foot – so, comfortable and so convenient – I love it!!!

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
10-20-2007 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,543
Joined on 05-28-2004

Post #: 48
Post ID: 5676
Reply to: 5329
Super Milq 6 channels diaries: almost there.
I did not do anything for a while on this amp but it looks as now I have almost completed the first amp in it’s final, not prototype version. There are just a few minor things left but the core is already there. All 6 channels are fully flitted, tested, and operational. I would need a day of work on it and I will be through…




"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
10-27-2007 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,543
Joined on 05-28-2004

Post #: 49
Post ID: 5744
Reply to: 5676
Super Milq 6 channels diaries: Final ++
Ok, I took it one notch further and moved the crossover in Fundamentals Channel (D) form speaker level to line level – very very very nice result. Below is the updated circuit and the response of the Fundamentals Channel ...




"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
10-27-2007 Post does not mapped to Knowledge Tree
Paul S
San Diego, California, USA
Posts 2,156
Joined on 10-12-2006

Post #: 50
Post ID: 5745
Reply to: 5744
Speaker vs. line; cap vs. coil; series vs. parallel
Romy, can/will you compare and contrast the two implementations according to what you hear?

Best regards,
Paaul S
10-27-2007 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,543
Joined on 05-28-2004

Post #: 51
Post ID: 5747
Reply to: 5745
The contrasts…
Speaker vs. line

Many benefits, Paul, it was well covered at my site along with many others places.

Cap vs. coil

Truly huge, only this would well-worth the admission ticket of the line-level. Do not also forget that in high-pass situation a coil works as shunt filter vs. cap as a series filter. In this case the signals in passband does not flow though the filter...


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
11-01-2007 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,543
Joined on 05-28-2004

Post #: 52
Post ID: 5780
Reply to: 5744
Super Milq 6 channels diaries: I am through

Ok, now it is done and it is official as I see nothing available for conceptual improvement in the crossover circuit. Interestingly this version offers the most interesting sound as well, since the circus was tune for sound, not vise-versa, it is what was expected. The below is the last version and I am intend to leave it as is. There were no strategic changes since the last version but there was minor playing with loadings and gain to shape the sound in a way I feel it should be.

http://www.GoodSoundClub.com/TreeItem.aspx?PostID=5765

Here is the brief online:

1) Lover Bass Channel:  the crossover point was moved to 78Hz
2) Upperbass Channel: the plate of the ½ 6C33C was loaded against 4000R instead of 1100R. The drop in the voltage divider was changed accordingly.
3) Injection Channel: was added mechanical frame to the speaker for precise time-aliment and fixation of the found position. The references setting is from minus 14dB to minus 10dB
4) Fundamental Channel: the high pass slope was moved to slightly higher
5) MF Channel: nothing was changed, was good as is.
6) “Water Drop” Channel: The tube was converted into triode and the Bessel 12dB per octave at 13kHz was implemented. The reference setting is from minus 7dB.



Above is the HF's high-pass filter for the "Water Drop"

It is it. In the two channels stages the drivers are at 205V, the output tube of LF channel (full tube) at 230V/200mA, the Injection and Upperbass output tubes are at 200V/150mA (half tube). The single stages tube are at 205V/32mA. I will make a picture when I close the amp up. Now I need to convert the second amp… I do not whant even to start it... to much work...

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
11-02-2007 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,543
Joined on 05-28-2004

Post #: 53
Post ID: 5788
Reply to: 5780
Super Milq 6-channels diaries: the final pictures.
Ok, the 6-channels super Melquiades is done, closed up and I made a few pictures of the beast. I have to admit that I do like how it amps turn out to be packaging-wise: the layout turned out to be very good for 3 channels as well and for 6-chennals. It looks and feel like Soviet military helicopter form 60s – well is what it is… As now there are no major further changes that I am planning to do. Among the minor things I would need sometime in future to put my Schottky diodes on larges heat sinks and to experiment with 2 alternative transformers for MF channel that I have (currently I use Pieter Treurniet’s Trebute for MF). I will do it after, when the right channel of the 6-ways Super Milq will be done. I think it will take another month of two. Also, I would need to found a good-sounding regenerator for the amps: 388W each monoblock

 So far, enjoy the Super Milq porn…




"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
11-03-2007 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,543
Joined on 05-28-2004

Post #: 54
Post ID: 5791
Reply to: 5788
The new filtering capacitors for my tweeter channel.




"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
11-04-2007 Post does not mapped to Knowledge Tree
Antonio J.
Madrid, Spain
Posts 272
Joined on 08-16-2004

Post #: 55
Post ID: 5792
Reply to: 5791
What are those?

I had never seen anything like that. I like their looks. Do they "sound" as expected? I'm fascinated for your efforts with your system. I think I don't have the endurance to go throughout all that, provided I had the time, space, resources and knowledge, which of course I don't have. Good luck Romy, I hope you get where you want to arrive.

11-04-2007 Post does not mapped to Knowledge Tree
drdna
San Francisco, California
Posts 498
Joined on 10-29-2005

Post #: 56
Post ID: 5793
Reply to: 5791
Why the vacuum caps?
The question in my mind Romy is: why?  I will be interested to hear your comment on what your goal was to learn about your system in introducing these and what the results are.  After the extent to which you have described the sound of your system, it will be very instructive to hear your comments.

I have toyed with the idea of using these for RIAA circuits in a phono preamp, since the required pF values are appropriate and they should offer minimal distortion.
11-04-2007 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,543
Joined on 05-28-2004

Post #: 57
Post ID: 5794
Reply to: 5793
Capacitors are like cholesterol - migh be good and bad.

 drdna wrote:
The question in my mind Romy is: why?  I will be interested to hear your comment on what your goal was to learn about your system in introducing these and what the results are.  After the extent to which you have described the sound of your system, it will be very instructive to hear your comments.

I have toyed with the idea of using these for RIAA circuits in a phono preamp, since the required pF values are appropriate and they should offer minimal distortion.

Well, prior to personably bitching about capacitors let define what we are fighting in capacitors. Capacitors are like cholesterol: there are good capacitors and there are bad capacitors. The good or bad status is however is not only determined by the type of capacitors but primary by the why how the cap is used. If cap is a coupling capacitor (or PS capacitor) then it is squashed from both sides by differences of DC potentials and the dielectric of the capacitor has been already polarized. The small amounts of AC signal the flows over the cap has not significant strength to repolarize the cap’s dielectric. Why it is important? Because the what AC attacks the cap’s dielectric the dielectric acts like a cone on miniature loudspeaker, crating electro-mechanical vibration and consequentially the microphonic noise. However, in case a cap use no or little DC (as in line-level filter of feedback filter) then each single milivolt of AC forces the dielectric into re-polarization. Better dialectic less exposed to this event but what would be if the dielectric …is vacuum or air? In this case there is no dielectric of any kind. available for re-polarization. I was looking for year the right vacuum cap and all that I have seen with right fixed values were aluminum caps. Now I have eventually found a pure cupper cap. Will it be better than an air cap? I do not know but I will try, and I think this is the only way to answer the question.

Pay, attention the Melquiades nowhere uses the “bad-type” (location) capacitors. Wherever the circuit is called upon such a cap the amp uses RL filters or the caps with no dielectric (air, vacuum)

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
11-04-2007 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,543
Joined on 05-28-2004

Post #: 58
Post ID: 5797
Reply to: 5788
The new Super Milq and the old Super Milq.
On Friday a guy that I invited long time ago shut me email informing that he should be in Boston this weekend. I have just one freshly cooked 6-ways Super Milq and just right functional Macondo channel. I did not wan to brash him off and I connected the old 3-ways Super Milq to temp just-made crossovers and decided to run it along with the hew 6-way Milq-Macondo assembly. None- of the 9 channels were calibrated yet and there was many aspects of sound that I do not like but to my big surprise the general imaging was not absolutely destroyed. The installation did not do it’s customary “kinky” things - like curve the presentation in parabola – but the imaging was much better then I anticipated form a playback driven by essentially different amps.


"I wish I could score everything for horns." - Richard Wagner. "Our writing equipment takes part in the forming of our thoughts." - Friedrich Nietzsche
11-24-2007 Post does not mapped to Knowledge Tree
op.9
Planet Earth
Posts 68
Joined on 01-26-2007

Post #: 59
Post ID: 5939
Reply to: 5780
Bias confusion
Romy,
Could you help me understand your biasing scheme with this version? I thought I understood the original Milq circuit - but the only channel that looks like that to me is the D channel. I don't get A and B at all! what is the 50 ohm resistor doing? is it just a grid stopper? I assume you can adjust bias and 0v at input in each stage - but don't the two red legs (on channel B for example) work against each other?
Thanks in advance!
james



everybody used to call me James in my past other-worldly life.
11-24-2007 Post does not mapped to Knowledge Tree
Romy the Cat


Boston, MA
Posts 9,543
Joined on 05-28-2004

Post #: 60
Post ID: 5940
Reply to: 5939
The Super Milq’s input: electrical perspective.

 op.9 wrote:
Could you help me understand your biasing scheme with this version? I thought I understood the original Milq circuit - but the only channel that looks like that to me is the D channel. I don't get A and B at all! what is the 50 ohm resistor doing? is it just a grid stopper? I assume you can adjust bias and 0v at input in each stage - but don't the two red legs (on channel B for example) work against each other?

Sure.  Let live aside of idiosyncrasy of sound with gas tube driving fixed biased 6E5P. I have written about it in many places:

http://www.GoodSoundClub.com/TreeItem.aspx?PostID=5533

…and it would be totally different subject.

Let look at the Super Milq’s input just from purely electrical perspective. The basic premise is to get rid of a DC blocking capacitor at input. To do it we pit a series dose ohms resistor and then apply a contra-collage on another side to keep the DC balance at input at zero volts. Then we need to put at each channel own filter.

Here is the initial filtering idea.

SuperMilq_6Ch_5.jpg

I intentionally kept all drafts on the site to show progress and how one thing flew into another. Eventfully the series capacitors were replaced with RL filters and it make too many series resistors in signal pass, so the objective was to combine the filtering and biasing duty of the resistors together.

So look with what we end up:

Channel A: Has RC (substitute for L) filter at input and the 30K filter resistor is used as yellow biasing resistor. Look at the Draft 3. R14 and R27 are the same resistor and if so then we do not need R17 (red), the purpose of Red resistors is apply positive contra voltage on the left side of bias resistors but in the final draft on the left side of 30K resistor there is a common B+ voltage share be all channels. Surely, since we have much less positive voltage “sipping” through the new bias resistor (30K is more then 12.1K) then we need to apply much less negative voltage to the grid, or to increase the value of greed resistor. The 50R resistor is grid stopper; it might or might not be there – does not matter for THIS circuit. (The need of grid stopper for fast tubes is another subject all together)

Channel B: The identical story with the Channel A only instead of 30K series resistor we have a voltage divider that from a prospective of filter/bias is the same fixed series resistor. Pay attention that of I can the cable on the left side of the divider, disconnection the Channel B then I would need to change value of the Red 402K resistor at the bottom of the image as the total balance of positive (coming from 402K resistor) and negative (returning back from each channel) will be changed.

Channel C: this is practically standard Milq configuration with L-pad at input – there is not filter in here. You would ask me why I did not use the same approach as I used in Channels A and B – getting rid of Yellow and Red and letting voltage to pass via the attenuator to common positive. The reason is because my L-Pas is laden type, what has constant input impedance and variable output impedance. So, the circuit balance the 0V dc on left and right from the L-pad, making the channel DC do not care about the L-Pad. If in my L-pad I would flip not 2 resistors but 4 and the output impedance was constant then I would employ the same approach as I did in the channels above.

Channel D: This is quite complex. We can’t used the approach as above as the DCR of filtering coil is too low (250R) and the negative bias voltage shorts itself to ground via the coil. So, we need here a fill scale biasing Yellow resistor to keep the tube happy. What happened at left side of the Yellow resistor? Some voltage comes from positive bias, via 36.6K resistor and across 250R of coil to ground. So, why do we care, we juts  adjust the voltage of common positive bias and it will be it.

Channel E: The RL filter, the situation is identical to the Channel D. It might be a concern that I have we have too high series resistance in a grid chain. In practice is dos not sound as HF-challenged. That impedance with Miller capacitance of the 6E5P makes ~ over 100K low-pass filter … not so damaging for a fast, oscillation-incline tube.

Channel F: It has input cap that does not transmit DC, so we should not vary about anything and juts run one green resistor with negative bias supply. However, some voltage drift via coil to ground, passing through the L-Pad with variable output impedance… Eh, Not good! So we need to put a Yellow “bias stopper” into the game and to get 0VDC on the left side of the Yellow resistor. Then positive will not flow to coil because it will be blocked by the cap and negative will not flow anywhere because it balanced by red resistor. This way flipping the L-Pad affects nether bias nor impedance. Not that the L-Pad has constant input impedance against which the CL filter is written (it is Bessel). It was very important and a change if the attenuator impedance would lead to change of crossover point and subsequentual throwing the tweeter off the time aliment.

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
Page 3 of 7 (132 items) Select Pages:  « 1 2 3 4 5 » ... Last »
   Target    Threads for related reading   Most recent post in related threads   Forum  Replies   Views   Started 
  »  New  Super Melquiades Amplifier...  About the Super Melquiades Bass....  Melquiades Amplifier  Forum     29  187734  07-16-2005
  »  New  Fun with transformers?..  Re: An amplifier is not a subject but a service.....  Melquiades Amplifier  Forum     7  66025  10-21-2005
  »  New  Building Melquiades: Chronicle of full-range..  VR2 issue leading to jump in current on 6C33 tube...  Melquiades Amplifier  Forum     44  253241  06-09-2006
  »  New  5 Channel Version of Melquiades..  Very easy....  Melquiades Amplifier  Forum     21  168587  07-23-2006
  »  New  RAAL “Water Drop” tweeter for Macondo...  Your comment takes me by surprise...  Horn-Loaded Speakers Forum     77  673569  02-16-2007
  »  New  The one-stage Melquiades...  Tubes vs. Speakers vs. FR...  Melquiades Amplifier  Forum     73  463769  04-21-2007
  »  New  The single-stage Milq and power Supplies...  Just the tank...  Melquiades Amplifier  Forum     10  64604  05-03-2007
  »  New  A DSET is better then an expensive SET..  DIY Stradivarius...  Audio For Dummies ™  Forum     41  252885  09-21-2007
  »  New  Amplification and Consciousness...  Freedom of expression vs. something to say...  Playback Listening  Forum     15  75390  01-07-2008
  »  New  My (Amplification + Acoustic System): what is next?..  Macondo and Melquiades in the NEW room....  Audio Discussions  Forum     41  206333  01-10-2008
  »  New  All Active! A DSET and multi-way acoustic system...  Hahaha...  Audio Discussions  Forum     14  81121  01-31-2008
  »  New  The Melquiades' "Remote Biasing"..  The Melquiades' "Remote Biasing"...  Melquiades Amplifier  Forum     0  14695  02-05-2008
  »  New  A proper implementation of low-pass filters..  Low Pass...  Melquiades Amplifier  Forum     4  33692  02-18-2008
  »  New  Incorporating active crossovers into DSET..  Thanks...  Melquiades Amplifier  Forum     2  30305  07-22-2008
  »  New  Single-stage Melquiades vs. DHT amps..  A hallucination?...  Melquiades Amplifier  Forum     397  2590031  11-22-2008
  »  New  If you’re multiamping then use passive-line lever cross..  Crossover and DSET?...  Audio For Dummies ™  Forum     3  37093  01-21-2009
  »  New  The DSET perspective examines the Herb Reichert article..  Are you still in Reutlingen, Germany?...  Melquiades Amplifier  Forum     5  68064  07-01-2009
  »  New  Training amplifiers..  The Milq's demands for burning...  Melquiades Amplifier  Forum     16  81446  03-20-2006
  »  New  Think ahead how to measure the DSETs gain...  The calibration mode is for DSETs not for SET....  Audio For Dummies ™  Forum     2  18942  09-17-2009
  »  New  Amplifiers heat… a real-estate solution?..  I have seen this simular concept...  Melquiades Amplifier  Forum     1  15392  09-18-2009
  »  New  About DSET-driven multi-way acoustic system maintenance..  About DSET-driven multi-way acoustic system maintenance...  Horn-Loaded Speakers Forum     0  18125  11-01-2009
  »  New  Thomas Mayer’s Triamp..  It is much more then juts "properly calculated and...  Melquiades Amplifier  Forum     2  25758  03-03-2010
Home Page  |  Last 24Hours  | Search  |  SiteMap  | Questions or Problems | Copyright Note
The content of all messages within the Forums Copyright © by authors of the posts