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Enough SET Power for Rock and Roll

I'm still trying to figure out what SET amp would sound best for Rock and Roll (and other music but especially Rock) on Klipsch Cornwall II speakers (101dB efficiency) in a room about 18x13 (with kind of medium acoustics - not live, not totally dead.) On a Marantz 2230 (which sounds very good, surprisingly good for being ~35 years old and 30 watts of solid state) I found that when I crank up the Rock and Roll on the Cornwalls I'm listening from about 89dB to 97db, but frankly if I wasn't worried about clipping or blowing out the speakers or receiver I could probably enjoy an occassional 100 dB :) - but if I have to live at 97 dB and below I could. (Measurements made with a Radio Shack meter set on fast, C weighting - taken from 1 meter away from the speakers, and also at the main seating position which is about 10-11 feet from the speaker plane.)

From many posts here and over on AudioAsylum it sounds like a 45 SET amp would sound great but might not have enough oomph - although that isn't 100% certain. It seems that a 2A3 SET amp would have a better chance of handling the loud music and the "complexities?" of Rock (and orchestra music) vs. say simple instrumentals and vocals. Next up would be a 300B SET, more power but some people seem to think it gives away some of the "magic" of the 2A3 and especially the 45. It isn't so clear to me from reading the various posts how any of these tube types do on the low end; I think low end (reasonably deep and tight) is needed to do Rock and Roll well - but so is good midrange and highs, so it's a balance, of course.

What do you think, more power and listen loud with ease, ie go with a 300B, or can a 2A3 or possibly a 45 do it all? Or is it possible that SET just can't do Rock and Roll seriously with 101db speakers in a 18x13 rom? In which case, next up is what kind of tube amp? If SET makes sense, I'd like to give it a try but I don't want to push physics or the budget too hard with experiments that aren't likely to work.

Thanks!
hi_hifi
charles1dad's avatar
charles1dad
10,250 posts
 
Hi Jet,
You consistently provide meaningful thoughts and perspective. I understand what you reasoning is for less frequent forum posting.  This endeavor of  assembling high quality audio systems is absolutely a very personal undertaking.  It is a true reflection of how we hear and react to the music we enjoy. Naturally our desires and goals will vary across a pretty wide spectrum. 

This explains the enormous number of options available to us in the form of audio products,. Amplifiers of many different topologies, circuits and power. All manner of speaker categories to choose amongst,  same plethora of choices for sources as well.  It's no wonder why we all have different systems that vary in individual components and obviously sound/music reproduction outcomes. How could it be any other way?

Jet when you write that perhaps only 5 of 20 listeners may like rock music heard in your system, that's okay. The only relevant point is that the sound is presented as you like it. Once you've determined what type of sound you want the next step is to go about achieving it. This is the key to long term home audio  listening contentment. I believe that you are there. 
Charles 
johnk's avatar
johnk
1,976 posts
 
SET amplifiers from 6-12 watts can drive most of my horn collection to Rock concert SPL levels in home. But you do have to have a massive horn loaded design to do this and it must be designed for lower power.  I cheat a bit I have 1 system that is horn loaded to 75hz and with that I run a powered bass system this can run on the wee output of a 45 SET amplifier and still produce peaks of 108db 3 meter before its going into massive distortions. I know many do not mind when the SET amp does so its a bit pleasant but I find it fatiguing and prefer to not push the amp or loudspeaker. I have no limits on music I play no limits on SPL but still no free lunch.                                                                                                             Hoffman’s Iron Law of Speaker Building

1) Bass Extension

2) Efficiency

3) Small Enclosure

The law is that you can only have two of these three attributes in speaker building.  Ideally we would want all three, we want speakers with good bass, can play really loud, and are small.  Unfortunately we cannot have all these.
jetrexpro
506 posts
 
The horn system I heard recently was really big with two Altec Lancing speakers for the lower mids per channel. It think the cut off point was 50hz and then 18 inch sub woofers took over. These subs were driven by 500w Crown amps. 50hz and above is handled by a 26w SET amp by Art Audio. The sound of this system playing rock music was a moving expirence. Pure dynamics and immediacy. This was a huge system that required a large room and nieghbors that are far far away. All of the horns in this system where made of wood with lots of tender love and care. The drivers for the horns are very expensive...the whole system is very expensive....but when one expiriences a system like this one is confronted by what is possible in reproduced sound and forces the listener to evaluate their own system.
wolf_garcia
6,741 posts
 
I owned a pair of Altec A7s for years run both full range and later biamped, mostly for live sound applications…the rare times I used these for stereo playback they were simply amazing, and you could run them from 20 watts…(My KLH model 20 compact system could get these things singing!). Likely not the most accurate things, but there's a "wooden" tone to them that is really appealing, along with that amazing middy horn (able to put out some serious sizzle also). I, and most every audio fan/musician I know from those days who is still alive, have moved on to the world of more accurate and more full range things that actually fit in a listening space smaller than Versailles…now for PA it's all about clear small horn loaded speakers with subs, which are simply better…not woody, just better. Still…loved the A7s.
atmasphere's avatar
atmasphere
12,014 posts
 
but I rarely hear those loudness queues you are speaking of. Even on very dynamic orchestral music I hear power and it even seems that there is additional headroom to spare.
The way you would notice them is if the system sounds loud.

The use of a powerful subwoofer system can help out an SET quite a lot!
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