Tube amps and speaker ohms


In your opinion , do push pull amps work better with 8 ohms or 4 ohms. .I am under the impression the lower the ohms, the more power is demanded from the amp....Another question, are there low powered SET amps ,and high power SET amps?
I'm looking at a 40 watt 845 tube amp for my 8 ohm, 89 db speaker.. just cked the Thor has a 86 db W18 midwoofers(2 per cabinet) and a 88 db tweeter. Will an 845 amp rated 40 watts be able to drive the 86/88 db speaker? With authority, bass, mids, highs, in dynamic sound stage? Synergy? Or poor match?
bartokfan
>>I get snides and insults due to lack of tech knowledge, snotty attitude, "mister-know-it-all", negativity, closed minded-ness<<

You make stupid statements.

If you open the door, people will walk in.
The point of the topic was to ask the GENERALIZED question that tube amps prefer 8 ohm speakers(though even 8 ohm speakers can dip to 4 ohms on huge orchestral challenges).

The answer to that is 'yes!', regardless of the tube amplifier technology.

The 4 ohm taps on almost all output transformers (excepting those that the 4 ohm tap is the *highest* tap). perform to a lower level than the other taps. The loss in bandwidth and increase in distortion is readily measurable and audible.

IOW: "Anytime you are investing in tube amplifier technology, that investment will be best served by a speaker that is 8 ohms or more, all other things being equal."
Don't know if anyone is still looking at this thread (which I found very informative as a newbie), but I thought I'd just report back now that my Yaqin MC-100B (4 x KT88's) has been with me for a couple of days.

It sounds amazing!! Okay, it's my first tube amp so maybe this is just me discovering that I prefer tubes to transistors, but I'm hugely impressed. A very full-bodied, yet smooth sound with lots of powerful bass...lovely. By the way, I didn't get to try the supplied chinese KT88's as one got smashed in transit. It's running with a matched quad of winged-C KT88's.

Anyway, to get back back on topic, it drives my B&W 804S speakers, which I believe are considered a difficult load, very well indeed. In 'ultralinear' mode (apparently 60wpc) there is plenty of volume (without clipping) available and the bass is very deep & powerful. There's a lot more of it than there was with my transitor amp, too...which is to my liking. No sign of the sound becoming confused and incoherent at higher listening levels. In 'triode' mode (30wpc), the amp still drives the speakers okay at lower volume levels, but I sense that it does struggle a little when asked to play louder . I prefer the character of the sound in ultralinear mode anyway, so that's of no concern to me.

But, even though I'm more than happy at present I guess I should still look to audition some alternative speakers, as maybe I just don't know what I'm missing!
David, tubes do sound magic, but not to be a party pooper, you are probably enjoying some of the harmonic colorations. Many folks do find this pleasant to the ear and since you paid for it, there is no reason for you not to enjoy it.

Better suited speakers will give you a much more accurate and natural sound, with less of the colorations. You may at first not enjoy it quite as much, and it may actually sound more like a transistor amp.

A good tube amp setup sound remarkably the same as a good transistor setup. I personally prefer tubes, as to my ear, they achieve the most accurate and natural reproduction of the recorded material. That you will only experience once you get components that work well together.

I think many will agree with me that the process of acquiring the correct components can take many years but is very enjoyable every step of the way.

Enjoy.

Regards
Paul
Dear Paul: +++++ " prefer tubes, as to my ear, they achieve the most accurate.....of the recorded material. " +++++

Please could you explain how the tube technology can be " accurate " to the recording?

Normally the tube is a self harmonic generator ( that does not exist on the original signal/recorded signal ) and normally too due to its high output impedance a tube amplifier is everything you want/like but accurate handling the electrical speaker impedance curve.

Regards and enjoy the music.
Raul.