SET vs OTL

Bill I have much experience with SET and audio design. Transformers mater as much as tube type not all 300b have weak bass rolled off hi. And as far as 45 50 SET as you say the best. Best for what? at 1.5 watts what can you drive? You need a loudspeaker designed to run off such low power and I have built many. And this low power doesn't drive woofers into low frequencies very well. Most of the loudspeakers I design for 45 SET etc have little bass below 40hz since 45 SET has little drive. If I want bass to 25hz or lower need biamping. So I agree 45 SETs best for biamping;) Its the transformer and amp design that gives extended range not the tube type. Bill with a bit more experience you will learn this. Take care and happy listening.

Marty I thought your post was funny.

John,

Glad to provide a laugh.

Your last comment is interesting in that I had posted earlier looking for info on loudspeakers that provide:

A) Appropriate sensitivity and load for a 45 SET amp

and

B) Sufficiently flat and extended bass response to even judge the bass capabilities of these amps (i.e.- no biamping).

Zu's full range passive (Essence?) looks like it might qualify. Any thoughts on this or other candidates would be appreciated. Again, budget and availability are considerations here.

Martykl,

You really can't ask a question like that without specifying your desired loudness level. 80 dB vs 100 dB - 10x the power!

I recently spent some time driving the 90 dB/W DeVore Super 8 with a pair of 45 monoblocks. I tried it at first just as an experiment, and I discovered, with listening levels of 80 dB on peaks in my large room, the (jazz) bass lines were incredibly articulate - perfectly sculpted. *Much* better than the 300B monos I'd just been using.

Is this a recommendable real-world combo? No, of course not - not unless you listen pretty quietly! My point is that, despite the inappropriate pairing, I could still evaluate the bass of these two sets of amps - and, in both cases, it had exactly the characteristics I have come to expect from these two output tubes. (And, while, again, not recommended, this combo was so good I left it setup this way for weeks. I'm trying to train myself to like lower SPLs anyway - and with this setup I could.)

If you want examples of speakers that can be driven cleanly and dynamically to moderately loud levels with a 45 SET amp, and have bass flat to close to 20 Hz, I can give you two: HE versions of Audio Note AN/Es and Supravox field coils on open baffle. The latter supported by powered subs (TBI) below 50 Hz.

If you want LOUD levels, I think you have to go to front horns and/or speakers with powered bass modules (Zu, others).

Typo - of course I meant 100x the power required from 80 dB to 100.