Seriously considering tube preamp…opinions?

Tubes add serious harmonics to terrible recordings to make them sound better.   They also add harmonics to good recordings to make them sound worse.

When i listened to tubes on good recordings, I liked the way they sounded. That was compared to solid state A/B and D class. I have not however tried the Pass Labs Class A. I'd like to do that.

hilde45 OP211 posts02-28-2020 8:24pm

When i listened to tubes on good recordings, I liked the way they sounded. That was compared to solid state A/B and D class. I have not however tried the Pass Labs Class A. I’d like to do that.

--------

^^-above-^^ IMO, I’m not so sure I buy 100% in to the comments above regarding good recordings sounding worse with tube amps, added harmonics, etc. And particularly not with higher quality pentode / ultralinear tube amps designed with zero feedback. Just like solid state, not all amps are created equal.

hilde45,
When you do audition Pass, ask the dealer if you can listen to the INT-60 with 3-4 different types of speakers. Nelson’s amps can truly sound quite different from one speaker to the next. And, some of the higher-efficiency  speakers are not as "musical" sounding to me when paired with some of his higher current amplifiers. A good Pass dealer will know what to show you and what pair them up with so you can hear differences.

Danvignau 2-28-2020
Tubes add serious harmonics to terrible recordings to make them sound better. They also add harmonics to good recordings to make them sound worse.

Tvad 2-28-2020
While a bit of an exaggeration, this is true, although tube amplification often sounds better at clipping output level (as @atmasphere has explained).

It’s a primary reason I have suggested Pass Labs Class A solid state amplification (and gently joined by @almarg).

In addition, Ralph has explained in many threads that while tube amps usually have greater **total** harmonic distortion (THD) than solid state amps, they usually have lower amounts of the components of the distortion to which our hearing mechanisms are most sensitive, and which are most objectionable from a subjective standpoint. Namely certain higher order odd numbered components, such as the 7th harmonic. Also, solid state amps typically (but not always) require greater amounts of feedback in the design than tube amps. Depending on the specific design that can often contribute to transient intermodulation distortion (TIM), which can be particularly objectionable and which is not normally specified or measured. And as far as I am aware a standard for how to measure TIM does not exist.

I almost always agree with the insights Ralph provides here, and that certainly applies in this case. At the same time, though, it seems evident that both kinds of amplification may or may not provide fine results depending on the specific amplifier and on how it synergizes with the particular speaker. So my philosophy when it comes to audio is to focus on the specifics of the particular equipment that is involved, rather than on generalities which usually hinge on matters of degree. And the main reason I leaned toward suggesting solid state amplification earlier in this thread is that in the majority of cases small two-way speakers are designed with the expectation that they will be driven with solid state amplification. Which as a result of its near zero output impedance (accomplished with the help of feedback in most cases) maintains essentially constant output voltage into varying impedances. And hence delivers more power into lower impedances than into higher impedances, as long as the amp is operated within its capabilities. I also suggested that among tube amps those having low output impedances (for a tube amp) are likely to be most suitable.

Based on the first of Ralph’s posts dated 2-26-2020 in this thread, though, it sounds like the Salk WOW1 (and other Salk speakers), like the Daedalus speakers I use, tend to be more versatile with respect to the choice of solid state vs. tubes than many others.

Best regards,
-- Al