With all due respect Ralph, I am not aware of a 'warmth associated with real music(and tubes)' consensus. My take on it is simply a subjective preference over accuracy. I find real music to resemble a good, fast, flat frequency response of ss much more than typical tube sound. A no holds barred, pull no punches sound, right? Regardless of whether I prefer it or not. Which incidentally I do. It just can't have any detectable IMD/TIM. For example like my LSR&D amps. Very extended but also sweet. Nothing cold about them, just very linear. To each his own. |
I'm surprised you haven't taken Ralph to task with this premise. Or should I say I'm not? Fact is their is consensus that tubes are distortion for the most part. Also that the best of both converge sonically...to neutrality. Enter LSR&D. How do YOU define neutrality as it applies to audio? Btw, I do have ears and do come to my own conclusions but affirmation is sometimes also rewarding. Again, to each his own. Have fun.
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LSR&D is the company logo comprising the initials of 4 partners headed up by the late Dr. Marshall Leach at Georgia Tech University in the 80's. Bickering and in-fighting led to the company's early demise so few examples exist. Dr. Leach did offer the amp in kit form and there is a substantial following on DIY Audio. Lots of info on the net, re: The Leach Amp/ The Leach Superamp/ LSR&D. |
Ralph, thank you for your response. There is never a time I don't learn from you or Al. I haven't mentioned the issue of reliability. But I do remember a recent post on another thread where you pay respect to a particular ss amp. I expressed my opinion on how I believe tubes set themselves apart, namely heat. I could very well be wrong. It appears the capacitance issue can be overcome to a satisfactory degree,'different strokes' as the saying goes. However, you've pointed out that tubes are far more versatile in arriving at one's design goals. If I can arrive at life like spl, speed/transient performance, extension, bass definition, ultra flat FR/linearity, etc., iow perfect neutrality more so with tubes, then that's what I would prefer. I'm still kicking myself for having second thoughts long enough to miss out on acquiring one of your OTLs on CAM recently for very reasonable cost. I'm certainly not averse to considering tubes in order to take advantage of sota sq. I have as I've mentioned two pairs of tubed monos I really like. But more so as a novelty rather than serious long term listening just because their short comings are too blatant. They are fun but not exciting. I wish I could afford to put your designs through the wringer! |
I've owned a Perreaux 2150B and several Acoustat TNT200 and 120. All pure mosfet so I have some insight into the warm/tubey/mosfet sound and imo it's nothing more than a softening of leading edge transients. In effect resulting in what to me sounds like a bit of IMD or TIM. Imo BJTs sound better because they're effectively faster even though the device itself may not be. Whether this is deliberate or not, I don't know but I find BJTs to have better, more refined low level resolution. I think once you reach a sufficiently high level of fidelity, the novelty effects disappear as a matter of course. If the goal is reproduction of the signal, then the last thing you want is to be able to pinpoint the topology of the amp, no? |
Hey Bomb, it was rhetorical. He reminded me of the S-30 I missed out on buying recently. |
Nah, it's all in your head. It sounds the way it's supposed to ;) |
Sabai, Do you have to turn it too? That's the one I just missed out on. It went for 1200 |
Geoff, so it's your twin we've been dealing with? That explains everything. Stick around, you're in for a treat! |
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I've owned several Bedinis. 25/25, 150MKII, 250/250, 100/100. They're all good amps, not great amps. The thing that's lacking in them is speed. The fastest one is the smallest one, the 25/25. But still too slow imo. I don't get the hyperbole about it. It's not hard to find an amp capable of driving low impedance. Now having said that, I still have the 100/100 which needs work. It has a sound stage that is holographic. |
Google it and surf the banter about it. |
Yes, It's a well known article. But it doesn't really bring up anything we don't all know already. At least those of us 50+. I get all that. I mean I believe it, I remember the 70's:). So what I think you're saying is, it boils down to the question "how much is too much?" IOW, the devil is in the details. Enter the subjective nature of our hobby. I always knew diminishing thd with decreasing power was the way to go. That's what makes sense. It's a shooting gallery out there right now and the prey is ripe for the picking. However I think I have a handle on what the rules are. |
Well, I do know everything. And everything is that there is some degree of objectivity in assessing information from varying sources. The more the information, the more objective the assessment. We are after all part of the same gene pool. The key is to research sufficiently long enough/thoroughly to get a take on all aspects/perspectives you relate to. I have never been disappointed with a purchase after having done so. And I've made many. |
Ralph, can you describe live unamplified without reference to amplified? Where does 'warm' come from in reference to unamplified? To me, the 'holy grail' is 0 distortion. With that comes perfect neutrality vis-a-vis, 'live', no? Ime, non detectible IMD/TIM results in the intended goal when the FR is truly flat. I truly believe this is what we're all looking for whether we know it or not. It's the jargon that gets in the way of arriving at a real understanding of what constitutes live sound in an amp.
What are the loudness cues our brains use for natural, unamplified sound, or a tube amp? Without higher order harmonics, what do we use?
When you describe "bright" sounding amps, are you comparing to other amps, ie: tube, fet, etc.? Or are you using live unamplified sound as your reference? More often than not the comparisons I read are tube vs. ss.
I think live as an established reference for both tube and ss reveals the only truly accurate yard stick in ranking the performance of an amp.
Both fall short, some deliberately(usually tubed),some not(usually ss).
What you appear to be making very clear is that distortion is the arbiter in judging neutrality. So other than utility, tubes are not necessarily required to achieve the desired goal. And I don't want to beat you up on this but if I may digress, you did use the term 'warm' in reference to live unamplified sound.
Having said all that, I suppose my next question would be, 'typically, how flat is the FR of one of your amps? I mean if you stretched the tape out to 5 feet.
The most notable difference I've experienced among the amps I've owned and still own, is that character you touched on regarding volume. I have only two amps, both ss, that have that quality of high volume without fatigue. This is mine, and I believe everyone else's natural yardstick to recognizing life-like sound and coincidentally, noticeable distortion.
And this is the crux of the situation as they say. It now becomes quite obvious that for the most part, you by default, are correct in that very few ss amps with that characteristic exist. All those apparently 'warm' ss amps are going to hurt just as much as any other low distortion ss amp when cranked.
However, it didn't take $100,000.00 for me to acquire that quality. But it did take time/research. Interestingly enough, my favorite LSR&D amps are also obsolete. I think it serves to point out that these amps are the late Dr. Marshall Leach's famed LOW TIM design. They can still be had as diy projects. Also, this design has been incorporated into some other brands such as Heathkit(vintage), some Crest(sound reinforcement), HK 990, to name a few. The other is my Boothroyd Stewart Meridian 105 monos. The Brits have a pretty good handle on what we're talking about here imo.
Also, I think the famous Bob Carver Challenge has a place in this discussion. Still not sure if Mr. Carver is in a league by himself. On the one hand ostracized for having the ability to mimic the sound of any amp, ss or tubed without having to copy the circuit, and on the other, celebrated for his sonic achievements. He's clearly shown that neutrality is a matter of circuit design and that the question of tubes or ss does not enter into it.
I still wish I would have scooped that S-30 before it was too late, though:)
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Well, my experience has been that sometimes the emperor is a good guy whose clothes have been altered. |
Of course not. As you say, and as I've also stated, specs are an indication of potential. What I meant was that sometimes the specs are not window dressing. Lots of horrible sounding amps have great specs but great sounding amps also always have great specs. But the point I was trying to make clear is that truly great sounding amps that happen to be ss are not as rare as you might think. |
I just sent a pair of those in mono to Hong Kong. Very happy customer. |
That must be the A-308 I noticed on CAM just before you announced you found one? Don't you just love it when a plan comes together! |
