Myth, perhaps but let look what might actually the myth migh be. There is nothing “on a paper” that presumes a good sound. 109dB sensitivity is not automatically means anything and a 300B SET is not a definition of some kind of abstractive quality. In fact 95 % of all 109dB sensitive playback that I have seen I would not consider worth affords as well and 100% of 300B SETs were not interesting. So, let do not refer to the specific, perhaps poor implantations and to the specific ignorantly setup installations.  Still, can we make any generalization? I do not think it would be necessary.

Scott, in your question there are tow phases: the phase about your setup and the phase about a generalization. In context of your setup I really do not know what is going on with you.  The confusion that from my point of view you experience is observable even in the format of your post. You’re unhappy about dynamics but wiling to address the problem with introduction of more powerful amps. More powerful amp will be able amplify the signal to the same amplitude, holding more inpout voltage, but it has nothing to do with dynamic range. To get better dynamic range you need a better amplifier. So if you are unhappy with your compressed 300B SET and if you wiling to make a generalization then it would make sense to try a dynamic-range capable SET, wouldn’t? Topologically and according to all theories the SET is capable to produce dynamic range that is unspeakable for PP, unless some tricks used in PP amps and those tricks have own negative effect to sound. Why your 300B do not have dynamics no one knows….

Still I do not know why you addressing the dynamics limitation of your elections (presumably it is the problems) with “I need an amp that can maintain the purity …. while delivering more power”? Did you heard those foolish intentions with powerful and tonally dead electronic that deliver high sensitively when the loudness goes up but sound still stay at 10% of what it should be? Well, with 90W PP it would be simple to accomplish… I certainly do not say that a powerful PP could not be theoretically interesting? I juts believe in what I experienced and I personally do not see PP that would be able to work with properly made horns.

Also, “to take control the 15" bass driver in my horns” is the separate issues and you know it. Wherever you expect this driver to work as upper bass horn the driver acts as a direct radiator. So, can a 90W PP drive a large and heavy direct radiator? Probably.  Would it do ”immediacy, presence, power, and punch - the life of the music” I do not think so, as well that I do not think that “the life of the music” might be a property of only audio methods.

Scott, as I always suggest before to make any movements or make any changes try to identify the real problem instead of a random addressing of abstractive dissatisfactions

http://www.goodsoundclub.com/TreeItem.aspx?PostID=432

You can get 800W amplifier but .... is POWER something that you are looking?

Rgs,
Romy the Cat

I do not think that it is a mater of the output tube. Yes, the 300B is crappy tube but it is too easy to blame the under-performing tube. I would say that in the situation that Scott is experiencing the problem is not with his amplifier but in the ideological place that his amplifier ocupates in context of his installation and with the assessment techniques he uses in his reasoning-causing audio judgments.

What I mean is the Scott (or most of the people who believe that they “do audio” at that mater) asked pretty much the question about nothing and the question that has no relation to practical audio. The fact the Scott used the words that audio people can understand (horns, SET, cables elevators, etc…) does not necessary make his understanding of his own question. I do not knock to the Scott’s door but let look what the conversation was all about. Scott completely voluntary accepted an amplifier that somebody told him was a SET amplifier.  With the same success someone would tell him that it was an amplifier that user the cold fusion…. How the hell the DRD-300B’s sound similar to what SET should sound I do not know. I also do not know where Scott found those “wonderful nuance, subtley, harmonic richness, and tonality” into the sound of THAT SET.  What motivated Scott to use that Welborne Labs DRD-300B only god knows, probably he found it in garbage; he should put it back there… Now let rephrase the Scott’s qestion:

“The past 6 - 8 months I have been living with very efficient speakers (~ 109dB/m/w) driven by an amplifier that I have no idea how it performs. The amps use 300B output tubes for about 7 wpc. On paper, this should be a match made in heaven. In fact, the combination is capable of many things that my idiots-friends form AA taught me it would. It is really pleasing, especially on simple or crappy. Except for one thing – I do not know what it is but let me I call it dynamic. I am not referring to loudness. It can deliver more undistorted volume than I care to listen to. I'm referring to other set of properties that my friend form Audiogon told me about. If you go to the symphony, or live blues, than you know what I am talking about. Next week I'm taking delivery of a 90wpc PP amp, to audition in place of my current cold fusion amplifier. I need an amp that can maintain the purity of tone and harmonic texture that I head the SET might have, while delivering more corrupted voltage into my big and heavy bass drivers that with higher voltage applied to them discontinue to be a direct radiators and become horns.”

Well, the problem is certainly not with Scott but with the general mental approach of audiophiles to their playback. Would Scott be a DIY person (the moronic people that I really cant stand) or buying ready-to-go-audio he never identified for himself the fact the he was using a fundamentally fatly amplifier. So, where the “SET qualities” come to the Scott live: from his own experience or from his repeating the rumors of others? The only advise I can give to Scott, or to anything else at this mater would be forget what he believe he “know” about the amplifiers and do not even to talk about amsp with anybody. Listen an amp and decide for yourself what the amp does wrong. Then, ONLY THEN, after identifying what was wrong, make any move or conclusion. However, this time the conclusion would be about Scott’s own observations but not about the picking and embracing the idiotic rumors of the Morons which whom he is accustomed to socialize in audio.

As I said in “My Playback Rules” section of my site there are very few properly performing SETs out there. SET with all it’s appearing simplicity is the most complicated amplifier if the proper objectives are in aim. The dam industry and the foolish DIYers brew SETs but they do not get the purpose of making an amplifier is not to arrange the electronic parts in a orderly fashion and is not to apply the dead topological concepts - doing this one can accomplish a properly operating but not performing amp. The purpose of making an amplifier is to get out of it the proper Sound. Most of those people out there do not manufacture Sound but juts products and the result of own egos. When you talk with them they talk about this the advances in different topologies but the would never show or even imply Sound that indicate that they looked for it. All those “electricianing” produce brainless equipment - which if 99.9999% of all audio out there.

Yes, there are very few interesting tube that work successfully in SET configurations, there are very few interesting sounding drivers (the most important), there are fundamental disability of SETs working in full range (here is why SET should be multiamped) and there are many other complication with SETs. Still the biggest problems are not with the SET’s mentioned or not mentioned difficulties but with the people who use/make them. As I am very convinced that in a hands of a person who casers and understand how a playback should Sound even a 300B amp would sound appropriately. Unfortunately the majority of the SETs out there do not sound as their designer/builders even tried to get anything out them other then a correct plate voltage… So, what would be the conclusion of using a dead SET:  to get a 90W mastodon?

Yeh, you’re right!

So far the Scott’s frustration do not sound different for me then a situation when he went to a fast food restaurant and was server with kept without frizzier 4 month old burger. Then Scott is eating the burger and begins to spread the pitching about the benefits of vegetarianism…

Still, the problem is not that Scott (and others) needs to change his current SET to the real one. What Scott needs to change is his ways how the audio problems should be approached, interpreted and resoled. Without it Scott will next month engaged in a new round of “inspiring audio frustrations…”

Romy the Cat wrote:

Topologically and according to all theories the SET is capable to produce dynamic range that is unspeakable for PP, unless some tricks used in PP amps and those tricks have own negative effect to sound.

Adrian,

what do you see fundamentally appealing in the symmetry of the differential circuits and what the relations between Sound the symmetry? Not to mention that the perfectly symmetric circuits do not exists. I’m very far form the people who could credibly explain to you the advantages of SE design but the dynamic superiority (among many other things) of a properly built SETs well described in literature.  You may try a good SET running in A1 with appropriate speaker and you would see that nothing could stay next to no-feedback SETs dynamic-range wise.

Beside the electrical advantages there are some usability advantages the even larger. In order to increase the dynamic range for 3dB you need to double power of your amp. Boosting the power you gain of dynamic range but this gain would be slower then the dynamic range gain that might take place if your increased the dynamic range of your loudspeakers. So, keeping the power low and the sensitivity of the loudspeaker high you have more dynamic range then the powerful amps and low sensitively dull loudspeaker.

If you run many watts of the “symmetry of differential circuit” (even in Class A1) against 110dB sensitive load then you have the “dynamic range” (primary coming from the loudspeaker) but you will also “loose a lot of sound” into the complications of that differential circuit. At least it was my experience. Yes I have seen people who told me the “properly made PP” might be equal to SET but in ALL those cases the people confidence collapsed what there was the actual needs to DEMONSTRATE SOMETHING to back up their promises. Also, I have to say that I feel that something very positive lives in the transformer cores…

I think the biggest problem with SETs is the complete missing from market any more or less capable high-sensitively loudspeakers that good SETs might be used with. The manufacturers and designers go for power in SET not for Sound as they need to sell those Sets to the customer with 95dB sensitive speakers. The alternative for them is only the foolish domain of full-range drivers with own set of unresolvable problems…

Rgs,
The Cat

So far the Scott’s frustration do not sound different for me then a situation when he went to a fast food restaurant and was server with kept without frizzier 4 month old burger. Then Scott is eating the burger and begins to spread the pitching about the benefits of vegetarianism…

ok...

I post on the usual web sites, including this one, because I hope that out of the dozens of replies, if I'm very fortunate, maybe one person will connect with me and understand what I want, and share their experience.  Mostly, the Internet posts are 99.9% rubbish, don't you think?

Cheers and Happy New Year,
Scott

skushino wrote:

So next week I will broaden my playback experience by adding my new 90wpc PP mastadon, and Romy's approved Lamm ML-2, in addition to my current DRD-300B amps.  And as a personal favor to the readers at Good Sound Club, I may share my results.  I don't expect anyone to base their next amp decision on my feedback

If you insist me to endorse something then this is why I make my Melquiades amplifier publicly available. This amp is made to sound is very certain way and this sound present the best that have seen form SETs. Interestingly that the Milq is not design around the idiotic believes in quality of parts, directivity of the wires and other BS – but it made sound in the way how it sounds by totally different means – it could not be understand by reading the schismatic. If you get Melquiades in your listening room driving your Elgars and if you find any amps that would have more dynamics (and at the same time preserving everything else!) then please let me know.

Your feedback would be very much welcomed. I have a LOT of notes about my live with this amp….

Rgs,
The Cat

Romy the Cat wrote:

what do you see fundamentally appealing in the symmetry of the differential circuits and what the relations between Sound the symmetry? Not to mention that the perfectly symmetric circuits do not exists. I’m very far form the people who could credibly explain to you the advantages of SE design but the dynamic superiority (among many other things) of a properly built SETs well described in literature.  You may try a good SET running in A1 with appropriate speaker and you would see that nothing could stay next to no-feedback SETs dynamic-range wise.

skushino wrote:

Rather than an intelligent discussion about the myth of High efficiency and Low power systems, most of your reply focused on the short-comings of my current amp.

Actually I do not think that you are correct in this. Rather than to have an “intelligent discussion”, dismissing the bogus myths I prefer you yourself to assess the validity of the myths and the sources that make you to embrace the myth. It has absolutely nothing to do with your current amplifier.

skushino wrote:

I have some curiosity to build a Melquiades, but since this is your first effort at a DIY amplifier project, I have serious reservations.  It is rare when a first effort in any field ever results in "statement" performance, or comes anywhere near achieving the potential of the concept.  So instead I will wait until you iron out the kinks, then reconsider.

Well your thinking operates by “achieving the potential of the concept” and by statistics of the “first effort” but this is not the thinking pattern that I use.  I assume you juts do not understand what Melquiades is, how it was created and what objectives were targeted while it was designed. The only reason I proposed you to get Melq because I’m absolutely confident that it would save you a lot of time, a lot of education and a lot of money. How many times you caught me blabbering about something that had no reasons?  I defiantly will not be overly pushing with my proposal; it is interlay up to you, though I do personably feel that you are not ready for the Milq. The Milq is public and feel free to return to your curiosity about this amp in a few years when you get tiered to chance the  “well proven solutions”.

Rgs,
Romy the Cat