Rerurn to Romy the Cat's Site

Audio For Dummies ™
Topic: Nothing elaborate

Page 1 of 3 (42 items) 1 2 3 »


Posted by Romy the Cat on 09-21-2007

For whatever stupid reasons the DSETs (Dedicated Single Ended Amplifier) are not as popular among audio people as they SHOULD be and this imperfection I am trying to attack.

So, if you use SET for whoever propose then it fine but if you even begin to think about more expensive SET  (more then $5K I would propose) then you use currently then DSET is what you should consider. A SET is a bandwidth and load limited devise  – there is not needs to fight with the Wind Mills and DSET topology is the answer to all SET problems.

Rgs, Romy the caT

Posted by Merlin on 09-22-2007
 Romy the Cat wrote:
For  A SET is a bandwidth and load limited devise Rgs, Romy the caT
Mine isn't.

Posted by Romy the Cat on 09-22-2007
Merlin,

I would take a liberty do not buy it. Are you saying that your SET is not sensitive to load and a different plate load has no change to the harmonics of sound? Do you say that your output transformer does not straggle with inductance vs. capacitance battles? When the last time you measured the response of your amp t full power? Can you elaborate how your SET reportedly does not suffer from the default diseases of the SET topology?

Rgs, Romy

Posted by Merlin on 09-23-2007
 Romy the Cat wrote:
Merlin, Are you saying that your SET is not sensitive to load and a different plate load has no change to the harmonics of sound? Do you say that your output transformer does not straggle with inductance vs. capacitance battles? When the last time you measured the response of your amp t full power? Can you elaborate how your SET reportedly does not suffer from the default diseases of the SET topology? Rgs, Romy


My SET doesn't have an output transformer. Just four tubes direct coupled. Bandwidth at full power is 2hz to 35khz.

Posted by Romy the Cat on 09-23-2007

 Merlin wrote:
My SET doesn't have an output transformer. Just four tubes direct coupled. Bandwidth at full power is 2hz to 35khz.

Well, your SET might be able to bypass fundamentals from 2hz to 35khz but unfortunately it is all the OTLs are good for as they severally skew up harmonics, making Sound more like a “frequency pushing” instead of music. Ironically, despite that you suggest that your SET is not sensitive to load some people, among those who make OTL to sound more or less acceptable, change of the OTL loading giving with OTL very high impedance (sometimes >50R). Anyhow, sometimes do for yourself an experiment: find a good 1:1 transformer and juts bring your signal though a transformer core you will see were the SET sound is born….

At any rate, with all my experience with OTL amplifiers, and I have see quite many of them, I do not recognize them as anything SET related, though they certainly topologically  might be SETs. The OTL are own unique animals, very intellectually elegant but hardly functional for Sound (unless you drive some strange electrostats or railway track suspended in magnetic fields….) 

Rgs, the Cat

Posted by Merlin on 09-23-2007
No. You are wrong. Harmonically, my SET is quite superb using either 300b or 811 I have unfettered access to the music in it's entirety. Transformer cores just distort the signal. Why on earth would I want one?


Posted by Paul S on 09-23-2007
Merlin, would you please be less cryptic?

Is it one of Ralph's OTLs or a DIY, or what?

What is power and what is full power bandwidth?  Into what sort of load(s)?

What is distortion at full power?  At 1/2 power?

Do you use an autoformer, or do you somehow keep the load optimised full range?

I am hardly a "spec" guy, and I much prefer SETs to other topologies, but I have to admit they have problems, all right, just as Romy says, and I have to admit that giving them less to do makes them really shine.

I would think an OTL would be a more not less tempermental SET.

How did you make yours different?

Best regards,
Paul S

Posted by Romy the Cat on 09-23-2007

 Merlin wrote:
No. You are wrong. Harmonically, my SET is quite superb using either 300b or 811 I have unfettered access to the music in it's entirety. Transformer cores just distort the signal. 

Well, I do not want to argue the OTL topic. It is not the subject of this thread first of all. Secondly I have heard too many OTLs to take comments about them credibly, particularly in context of a full-range operation. I am not qualified to discuses what is going on in a transformer core, I will leave it for your study, although if you satisfied with OTL result then you might not acknowledge or understand the difference.

BTW, in context of this thread: did anyone have seen a DOTL - a dedicate OTL where the OTL’s load were optimized for a narrow bandwidth of a given OTL channel?

 Merlin wrote:
Why on earth would I want one?

Because putting next to any OTL a properly sounding SET (Lamm ML2.0 for instance) you will learn what I am talking about. It was the way how I learned.

Rgs the Cat

Posted by Merlin on 09-23-2007
I don't have an OTL - I just don't have any transformers in the audible band that saturate, distort and roll off frequency extremes.

I have heard plenty of traditional SET's from Lamm to Wavac, AN, Kondo and many others. I know I could not live with their failings.

The design I use (I'm sure someone out there knows it and has heard it!) removes the problems your DSET seeks to cure. Simple and very effective.

Posted by drdna on 09-23-2007
I'm sure we'd all like to find out the specifics of this amplifier's design and theory, without any unnecessary mystery.  It would be nice of you to illuminate us all as to the details in a non-asinine way. 0.o

Posted by Merlin on 09-23-2007
I just assumed that this site, given it's position of authority on the subject and it's contempt for other forums, would have members who knew the model - seeing as it's been available for around 10 years and has been written about by many SET afficionados.

I also thought it might be amusing to see who identified it. My humble apologies if this ruse comes across as asinine to you. I personally would apply that adjective to comments dismissing the amplifer without even knowing what it is...

Posted by be on 09-23-2007
Must be a Berning

Posted by Merlin on 09-23-2007
Well done that man.

The Berning Siegfried. A licenced version is I understand soon to be released by Western Electric, using their 300B.

Posted by Romy the Cat on 09-23-2007

You are not as cryptic/abusive as you believe you are. I personally view your comments in context of your other commons at this site and understand that it is your style: do not express yourself but mysteriously bark from the side road. From this perspective your comments in this thread are very consistent to any other their where you participated. I certainly do not increment you – I juts mitigate my expectations accordingly.

On the subject (at least in the way how you turn the subject to be) let me to restate my position. I do feel that something very interesting, sound-making lives in a core or SE transformers. Also, I very much for a plate of the out tubes to be properly loaded. You proved my point about the sever dependency of your SET to load when you paralleled 4 tubes, I have see SET OTL with 32 tubes paralleled to drive the plate impedance down. With 4 tubes you are still at very high number of plate impedance and driving the conventional 16R load time are far from proper lodging. Even if you drive the load from cathodes and apply 10000000 db of feedback to balance out distortion then it still set the output tube far from it’s optimum load operation (not to mention the NF problems). It might be interesting to think about the precision of NF applying and the evaluation methods that where used to set the harmonic envelop of the closed loop but it would be interesting in the situation if a person has no needs to hide what he does or what he think.

With openness and observation facts instead of verbal mouth running this conversation is about nothing.

The caT

Posted by Merlin on 09-23-2007
Romy,

can I suggest you read about the amplifier in question before making comments?

The unit uses four tubes per channel - three drivers and one output tube. The unit has zero negative feedback. It is as pure as they come.

Directly heated triodes without output transformers. It's not upset by low impedences. It has fully regulated power supplies and absolutely zero AC filament hum. Take away the output transformers and you are left with the full unfettered harmonic qualities of the output tube unhindered by at the frequency extremes by transformer saturation that dulls transient attack. Ruthlessly revealing of the quality of tubes used, it's also ruthlessly revealing of source material and components further up the chain.

Whilst I admire your tenacity and promoting the DSET idea, my own feeling is that David Berning's solution is both neater and more practical - the only impediment ot it's acceptance, the dogmatic approach of many thermionic die hards. My experience suggests it's their loss.


Posted by Romy the Cat on 09-23-2007

 Merlin wrote:
The Berning Siegfried.

When I made the post about I did not read the replies above. The Berning Siegfried? Well, I did not hear this amp, in fact I did not hear any of the Berning amps that use that impedance matching patent. If it does work (it means sound) then you Merlin is correct as it will defeat to the DSET concept. It would be much useful if you Merlin in your initial replay mention that my DSET “rule” does hold ground because what David Berning offers.

http://www.davidberning.com/

http://www.patentstorm.us/patents/5612646-fulltext.html

I know little as now about the Berning ideas but I do know SET with transformers. I know that in context of SETs with transformers the DSET idea works very well. Even if the Berning impedance matching sonically sustainable then if still does not resolve a lot of additional benefits of DEST – elimination the interaction between the voice coli for instance and a few other…

Rgs, the Cat

Posted by Romy the Cat on 09-23-2007

 Merlin wrote:
... my own feeling is that David Berning's solution is both neater and more practical - the only impediment ot it's acceptance, the dogmatic approach of many thermionic die hards. My experience suggests it's their loss.
Well, I am one post behind in reading/replying again.

I undusted now what you are taking about. My severely-limited knowledge in electronics design does not permit me to make assumptions in electronics. To me the sound of amplifiers measured juts by the actual sound, not but the design concepts. In horns I can relatively accurate predict the sound of installation juts looking at the design. In electronic I can’t not. So, since I have no idea about the actual Sound of the David Berning's solution, or at least his amplifiers, I would withdraw myself from further discussion about it and will stay in this thread only in context the DSETs.

Well, the David Berning amps were more or less interesting then a DSET if the same driver/output tubes used? If the Berning idea works (Sound) then it would be an interesting question. I see some exploiting advantaged of DSET (crossovers, power mitigation, harmonics mitigation between the channels and some more). However, the only accurate concussion might be reached only with the actual conducting a methodologically pure experiment and listening the thing.

Rgs, the Cat

Posted by drdna on 09-23-2007
I was so impressed by the concepts Berning put forward, though Romy correctly points out that it solves some problems whilst creating others.  As is always the case, topological change is like a chess game. 

Anyway I actually bought a Berning (not the Sigfried, which I have NOT heard and so I cannot comment on it, and it may be different) early on.  I was really disappointed in the Berning amplifier.  I lived with it for quite a while, gritting my teeth and thinking I should be quite happy and what was wrong with me that I didn't love the sound.

I was actually not terribly disturbed when a thief stole the amplifier from me.  I was sorrier about the speakers at the time (a hand-made Focal affair).  I recall the sound as very uncolored and clear but lacking in emotive and intellectual evocative power.  Accurate but uninvolving.

Posted by Merlin on 09-23-2007
Must be the ZH270 you are talking about. I can understand what you mean with regards to the PP device - it is accurate and doesn't suger the pill in any way. I personally don't think amplifiers should - colouration is a short term emotional fix - a long term intellecyual headache.

The ZH270 sounds very different indeed to the Siegfried, being a push pull design with feedback applied. I would say that for a lover of SET's the ZH270 could be construed as being harmonically limited, but only in comparison with the finest SET's and IME it destroys them in being able to accurately portray frequency extremes.

But if you think you have heard the single ended zero feedback design from exposure to the PP device, I can assure you you really haven't.

Posted by Paul S on 09-23-2007
Well, David Berning is about as clever as they come, Merlin, that's for sure, and you don't hear David making a lot of claims for his gear.  That whole step-up, HF PS/carrier idea is pretty cool, all right; I think Carver did one, too, years ago; but obviously what goes up must come down at some point.  While I can't say I connected the amp's character to its tricky circuit, I can say that the amp has a character, and further, and more important here, it has obvious limitations.  In fact, I seriously doubt that David himself would specifically recommend the amp for giant FR/multi-way speakers. I rather suspect he would say, "Try it," and let you decide for yourself.

BTW, I seriously considered the Siegfired for my DEBZs, but I chose the ML2s instead, and now that I've heard the Siegfried again I'm VERY glad I went the way I did.  So what?  The fact is that neither of these amps is an unlimited FR "super amp", despite the "ability" to drive truly stupid loads, and very much contrary to the drooling reviewers who blissfully use them with 2R, 88 dB speakers.  I am NOT saying the ML2s are "better", but I am saying that you are still compromised topologically with the Siegfried; IOW, it is no Silver Bullet.

Silent filaments?  The ML2s are DEAD silent; no hum,. no tube rush; nothing.  But we expect that, right?

"Fully regulated power supplies"?   If it works, then good.  But how many "fully isolated" LCLCLCLC supplies have I heard that delivered pathetic sound?  One of the things I do not like about the Siegfried is that it sounds "less free" than a nice conventional SET in its "sweet spot".

The Siegfrieds are nice amps, Merlin; but we're talking Stairway to the Stars here, and I think if you think about it, all "practical" considerations aside, even you would have to concede that the very best sound from any SET is limited both in terms of power and bandwidth.  I like my ML2s just fine, but this also applies to the ML2; I am not excluding myself, here.

Best regards,
Paul S

Page 1 of 3 (42 items) 1 2 3 »