4 ohm speakers with tube amps?


I'm considering the Seas Thor design, a MTM speaker at 4 ohms. I have a Jadis intergrated, doable?
tweekerman
Tweek, the Jadis Orchestra specification sheet shows 1-16 ohm impedance capability. So it sounds like it should be do-able. If the output has a 4-ohm tap, that should be the one to use. If not, the power output may not be the same at the 4 ohm load. The manufacturer says ok, so I guess it should be ok.
Yes the Jadis page does say somthing about the fact that even though tube amps are "known" for the problem driving low impedence speakers, not so with their amp design. Though i don't expect the output to be the same as with 6 to 8 ohm speakers. Always a trade off somewhere in audio, i definetly want the Thor MTM W18+T25 speaker, even if it meant the parting with the Jadis sound.
Just took a closer look at the amp, on top of the gold colored plate on the output transformer, 0-4-8, so like the Jadis page said, engineered for any speaker load. Which makes me even more impressed with this amp.
I have used tubed amps on 4-ohm speakers for some time now, so it can be done with satisfactory results. Can't speak for your combination directly, though.
4 ohm taps do Not Necessarliy equate to 4 ohm drive capability. My 27W EL34 monos are more relaxed and xparent on the 8 ohm taps. Course, like Z says, it all depends on the spkr. ymwillv...
Just don't trust all speaker companies. I got rid of my Thiels because they were rated at 4 ohms but readily dipped to 2.5 ohms or so.
Elevick, sorry to hear of your bad experience. I just financed a $2200 3 way speaker designed by a DIYer from Madisound. An absolute mess. 83db!!!, Not one good thing about this speaker, i sold them for $1K. That is funny though, 2.5 ohms! worthless! I'm close to ordering the Thor kit, she's a winner! Trust me the Seas Excel midwoofers are real performers.
Impedance ratings usually mention nominal (worthless?) and minimum impedance loads (valueable). Thiel offers quite a bit of detail re: the specs of their products. A low impedance load does not make a speaker "worthless" it just requires appropriate amplification. If one becomes surprised by true impedance loads after purchase, I think it indicates either a lack of homework prior to purchase or poor dealer support (poor dealer support would be unusual with Thiels).
Yes, true. Worthless for my ideal set up. Could you say in general the higher the ohms and db level, then the better the sensitivity and thus less stress on the amp, especially a tube amp. Thus the lower the ohms, the less response from amp, the less finesse. In general. I've heard good things about the Thiels. But i think i found exactly what i'm looking for in the Thor, for a heck of alot less than the Thiels.
I would never pay $2K+ for a 2 way, the Thiel 1.6. With the Thor you get 2 (TWO!) midwoofers/cabinet PLUS a "state of the art" tweeter PLUS one very beautiful cabinet, for less than... $2K. I'll post a review soon.
Tweekerman, yes I could say that about some amps, but the inverse is true as well. Some solid state amps don't work very well on very high impedance loads and the same argument could be used against those speakers. I look forward to your review.
Just for the record, I have auditioned the Thiel CS1.6's at a local dealer, and they sounded absolutely wonderful in his set-up being driven by a VTL ST-85, a compact stereo tube amp employing a pair of push-pull EL-34's per channel coupled to the speaker through an output transformer optimized for power delivery into 5 ohms. Although this model continues the Thiel tradition of 4 ohms nominal rating, with a flat curve and the >3 ohm minima falling above the bass range combined with mild phase characteristics, it also breaks some new ground for the brand by offering a rated 92dB sensitivity, which Stereophile actually measured to be a true 94dB (older Thiels averaged around 86-87dB). Given the 6 1/2" woofer size, this implies that any good quality, moderately powerful tube amp that is rated into 4 ohm loads should be able to drive this speaker just fine in medium-sized rooms, as I experienced.

P.S. - Tweek, you have often expressed a penchant for listening with your eyes, so I'll just comment that if a speaker's 'driver count & cabinet size to price ratio' was any indicator of its quality or sound, we probably would all still be listening to the ones we owned in back in our school daze. I suggest making a field trip to hear the 1.6 if you are able, and then tell me if you still don't think it offers great value for the money.