Tube amps for classical music FU29 vs EL34

Considering the Thor's impedance curves, it would look like a stronger (than ~40W) tube amp is needed. I would wait to get the speakers and try them out using the existing Jadis as a reference point. Cheers

Its FU29, not 4FU. The 300B is a single ended amp, so requires a sensitive db rating 92+ speaker. That part I understand from experience. The FU29 amp, Cayin 500, I'm not sure what kind of amp it is. Also does anyone know if the Cayin 734 will accept KT's?

Hello Bartokfan. I can concurr with M wilson's experience regarding bass response with both the el-34 and KT-88/6550 tubes. Grgm's solid advice on waiting until you get your speakers is a very astute piece of advise.Depending on your room size of course????....you will more than likely need a little more muscle,especially considering your speakers nominal impedence of 4 ohms. The jadis amplifiers are one of a handful of tube amplifiers that seem to respond well to a speaker with a low impedence due to there excellent output transformers and a 2 ohm tap.Most typical el-34 based tube amps will have a tougher time with 4 ohm load.The only el-34 equivalent tube that will give you the bass foundation and slam of a kt-88 is the original Genelec KT-77. The el-34 tube is a power pentode whereby the Kt-77 is a beam power tube like the kt-88 and can be succesfully substituted for an el-34 providing the screen-grid ratings of an el-34 are observed.Unfortunately... the Kt-77 is very scarce and typically very very expensive.Sonically.... the Kt-77 is a truly amazing tube when optimized in an el-34 circuit.It is even more liquid in the mids than a good nos mullard el-34 but possess's the bass drive and resolution of the Kt-88.The top end response of the Kt-77 is second to none and will easily trump any kt-88 or kt-90[genelec kt-88's included] Caveat....Using a kt-77 in a el-34 circuit will "not" give you any more power than an el-34. Best of luck on your endevour. Cheers David

Think of the KT90 as a 'heavy duty' EL34. A KT88/KT90 tube will have more bass than an EL34, as others have mentioned. They will also have more power, FWIW.

Interesting post David. What I was refering to in the EL34's is that they provide more bass than my friends single ended 300B Cayin(can't recall the tubes), which classical music sounded flat, IOW lacked a certain depth and height I'm looking for in an amp. So yes, I should get the speakers first, see how the Jadis responds. The Jadis lacks the deeper bass regions. My current speakers are 25 year old Philips 2 ways. Paper 8 inch cone, beautiful clear dome tweet. You hit on something about Jadis' transformers, the quality. IOW all transformers are NOT equal. And since this will be my "last amp" (notice I have the Philips for 25 years)I want to make it count. I don't make enough $ to trade off ,like you guys can. So ,seems its back to my orginal idea, a Jadis DA30/used, if business is good, new, sometime late 2005. The DA30 has KT88's. I'm sticking to my orginal plan, just got sidetraked alittle.