Member's recommendations for tube amplification

^^ a 1KHz tone really isn't anything like an actual musical signal, which is a bit harder to reproduce, but the sound pressure meter isn't going to care about that.

The speaker is measured in sensitivity, not efficiency, so to correct for that your actual efficiency is more like 94 db. I'm sure your use of the subwoofer is helping a lot!

I often listen at higher levels (95-100db), but the trick is that at those levels the system does not sound loud. My speakers are 98db 1 watt/1 meter and they are 16 ohms at the same time Classic Audio Loudspeakers model T-3). Plus I am usually using amps with 60 watts output and at that power the distortion is quite a bit lower (about 0.5% THD at full power despite no feedback). So the result is less loudness cues generated by the system, which allows for higher volume levels without it sounding loud. Instead it sounds relaxed and effortless.

^^ a 1KHz tone really isn't anything like an actual musical signal, which is a bit harder to reproduce, but the sound pressure meter isn't going to care about that.

The speaker is measured in sensitivity, not efficiency, so to correct for that your actual efficiency is more like 94 db. I'm sure your use of the subwoofer is helping a lot!

I often listen at higher levels (95-100db), but the trick is that at those levels the system does not sound loud. My speakers are 98db 1 watt/1 meter and they are 16 ohms at the same time Classic Audio Loudspeakers model T-3). Plus I am usually using amps with 60 watts output and at that power the distortion is quite a bit lower (about 0.5% THD at full power despite no feedback). So the result is less loudness cues generated by the system, which allows for higher volume levels without it sounding loud. Instead it sounds relaxed and effortless.

@clio09   

However, we found one interesting exception to that rule. Pairing a 12 watt 300B with a pair of Fritz Carbon 7 speakers (88 dB, 6 ohm) at a very popular audio show.

I believe @glennewdick  is reporting the same with his Finale amp.

I'm bringing this up because @teajay Terry London has brought up how a 1W output from the LTA MZ2S pre/amp was able to drive the Tekton Double Impact. His favorite combination is the LTA MZ2S as pre and a Triode Lab 2A3 (3.5W) for power amp. He finds that's all he needs to drive the speakers effectively and is loving this pairing/system.

Do you and others have thoughts about and an explanation for this? Thanks.

Very subjective for sure with 1 - 3.5 watts. I have talked to DI owners who experience did not match Terry’s with the ZOTL combo or good flee watt amps. Terry and others love it, others will not. No right or wrong here, just differing sonic pleasures. Very subjective for sure. We all hear differently and have differing expectations and sensitivities. This is one reason David, but a smart guy like you knows this 😊

Some are more sensitive to "underpowered" or "little headroom" in an audio system. Others hear the same system with no sensitivity to this and hear all the good. What is a black dot on a white piece of paper for some is not seen by others. We are fascinating creatures.

I used to own the original Micro ZOTL and used it on high efficiency speakers and it did quite well, were talking 98 - 104 dB. Again, I think a lot has to do with how large your room is and how loud you listen.

The ESL panels I am using now have adjustable sensitivity, from 70 - 80 dB. The impedance is pretty acceptable from 100 Hz to about 10K Hz whereupon it begins to drop down to 2 ohm pretty quickly (note the speakers do not go below 100 Hz and I bi-amp them).

Understanding the designers goal was to make a panel with a very small footprint that can provide extensive detail at low volume, he had to make significant comprises. So he said the heck with the rest of it and made a set of panels that are better than my ESL-57s, but not as flexible with amplification. While the recommendation was to use a 100 watt amp (ss or tube) I was able to use a tube amp that is 35 watts per channel to drive them cleanly getting SPL levels up to 90 dB, which is a good 10 dB more than my preferred listening level. The level of detail and clarity in the music is fantastic.

In addition to room size and listening levels, if an amps damping factor is synergistic with a speaker, a lot can be done with a little power. There is too much emphasis placed on headroom in 2-channel. although in home theater I think it's important. Less is more in many cases. Mind you I'm talking about the ability of an amp to drive a speaker cleanly to reasonable listening levels. Just because it can be done doesn't mean the listener will like how it sounds.