My room is 400 sqf and I listen mainly jazz and rock
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Judging by yr info, go for any 40+W rms /4ohm, spec'd amp fm any reputable manufacturer (Wavac, Nagra, Kr Enterprises, ??). 8 series tubes or 211 tubes or 610 tubes. That's quite a choice... whether they'll play music with yr particular spkr is another matter. They'll drive it though:)
I had used Antique Sound Labs Explorer monoblocks (about 45 watts SET based on the 805 triode) to good effect with Spendor SP 1/2E's in a small room (156 sq ft). The Spendor's are 88 dB sensitivity. I never ran out of volume with that combo. I play mostly classical including large orchestras at realistic volumes. This amp was given a very positive review by Art Dudley some time ago in Stereophile. A good and relatively inexpensive way to try out SET. Good luck.
Power requirements are so dependent on one's listening level and size of room, it is hard to say whether any SET amp will be sufficient for your needs. I would say don't overlook pushpull amps; many sound fantastic and some don't even give away any of the "magic" of SET (just ask those who listen to ruinously expensive, but incredible sounding Western Electric amps).
Personally, I don't like most higher power pushpull amps based on pentodes, like the 6550, KT-88, etc. Some pentode amps based on EL-84s actually sound good to me, though they don't have that little something extra of low-powered SET amps.
My absolute favorite is low-powered SET amps (based on 45 or 2a3). But, my speakers are reasonably efficient (99 db/w, have a high impedance, and I don't play them very loud). I do think you give up something with higher powered SETs, but some are very nice sounding. A friend had a Wyetech that used 211 tubes that sounded very good.
Now, for something completely different. While I really do like the way SETs reveal fine textures and detail in an unforced manner, there is a quite different magic that is available from OTL amps. OTLs are incredibly dynamic and lively sounding. The compatibility issue there is that they work best with higher impedance speakers. Still, I've heard them on a wide range of speakers and really liked the sound too.
My speakers respond well down to the 30s (I believe the specs are 3db at 34Hz ) and the amp does provide a very deep and controlled bass. I have measured response down to the low 20s, although that must be down 10-20db at those low frequencies.
The most critical thing for a tube amp is a speaker with benign impedance curve. Given that, youll be surprised how little in power is needed to provide high(ish?) volume levels.
I think 88db is a bit low for a 300B based set, but I am sure an 6C33, 805 or 845 based set will do well. I have a 22wpc 6C33 SET and it will blast my walls down if I turn it too high.
One of us is confused here. What do you mean by SE push pull? Aren't the two designs, single-ended and pushpull inherently different? Single-ended means that one tube (or set of tubes in parallel) reproduces both halves of the wave form (by modulating DC current flowing in the primary). Pushpull means that tubes reproducing the opposite halves of the wave are connected to the opposite ends of the primary, with the DC voltage at the center tap.
I don't know anything about the amp you mentioned, but it could be a triode, class A, pushpull amp. But I don't see how it could also be single-ended.
KR Audio produces a number of higher power SETs, that output 20-100 Watts SET depending on model. I have their SXI integrated on order with 50W output from the Kronzilla tube. I currently have a Ming Da with an 805/300b combo that puts out about 45 Watts and still has a lot of nice attributes of the SET sound -- not the last word, but not bad for the money. Other amps I was considering were the New Audio Frontiers with about 25W and the Mastertone 845 Ref with about 40W/channel.
Thanks for the link. The amp shown is a parallel SET. It has two output tubes per channel, but it is NOT pushpull. Rather, the two tubes are hooked up in parallel. Not only does this increase output, it lowers the output impedance of the amp.
I know there are a lot of SET purist who say that configuration does not work well. I have no idea if the drawback of this configuration outweighs the advantages. What I can say is that my amp (Audionote Kageki) is a parallel SET (2a3 tubes) and it sounds great to me.