• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Help identifying what I have.

You say that HE speakers aren't designed to make your ears bleed, then you say you want to listen at 119dB... I would suggest buying a cheap microphone, set it to peak hold, then see how loudly you can even tolerate listening. For most people who I have done this with, it isn't even 100dB.

Hiss and hum will be a result of too much gain in the system being paired with high efficiency speakers. This is a system that's not well designed; it's not the fault of the equipment designer.

Lastly, high power push-pull tube amps with lots of feedback have a power vs. distortion curve that starts high, gently gets lower at higher powers, then shoots up near clipping. A low power 2A3 or 300B amp that would be the magical "5 watt amplifier" will typically have very low distortion at lower power levels that gradually increases as power goes up.

I would very much be interested in what listening level you consider "too loud", as it would be another data point for reference.

I have everything in one room, albeit a small room ~11' x ~13.5'. The CW IIIs dominate the room. By the time I got everything setup I didn't have time this evening to let everything normalize for a decent listening session. I understand that 119 DB is quite (intolerably) loud. However I was talking about peaks of less than a second.

I have two DB meters I will measure what I listen to as far as an average. If as I suspect the average is in the 75-85 DB range then 25-35 DB peaks above that for rim shots and other transient sounds which are part of music would not be unexpected. I also have a calibrated Mic & REW, but I think that would be overkill for this exercise.
 

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I may have been born at night, but not last night.

I know how loud 110 DB at my listening position is. In my post where I mentioned this volume I used the term "peak" I further clarified it by using the term "transient" in a later post.

One time, while the missus was out, I was testing my multi channel system. I fired up an SACD of Pink Floyd's "Dark Side of the Moon." I had out my Radio Shack DB meter I was averaging about 100 DB with peaks in excess. That was about as loud as I was able to tolerate for any length of time.

However if you have an average listening volume of X, say 75 DB and there is a louder passage it could increase the volume to say 85 DB. Now on top of that there are transients which could exceed 20-30 DB. I posit you need an amplifier which won't clip or otherwise distort on those transients.

The CW IIIs are exceptionally efficient speakers. So even with a fly weight amp you should get most of what you are looking for and they will sound a lot more dynamic than an 86 DB sensitive speaker with a 200 watt amp.

If however you have an amp/preamp system with a very low noise floor and gobs of power I believe you will be able to hear a positive difference over the fly weight amp/CW III combination. At this point it is theoretical for me, but now that I have ultra sensitive speakers, I intend to play around. I don't have a good 2 channel SS preamp but I do have the M125s, a Dynakit ST70 unmodified, an NAD 2200 PE, an Adcom GFA 555 II an old Dynaco SS amp and lastly a Crown K1.

This is a pretty good slice of mid fi power amps to play with. Hopefully the VTA SP9 (not SP12) will have a low enough noise floor and work & play well with all the power amps.