- Dec 20, 2004
The basic purpose of an amp is to take a small line level signal and amplify it to be strong enough to push a transducer enough to produce sound. It really shouldn't add or subtract anything audible from the signal... it should just amplify it. They call an amp that does that "a wire with gain". There are lots and lots of solid state amps that do that perfectly. In fact, in the past 25 years or so, I haven't run across any solid state amps that aren't audibly transparent for the purposes of listening to music in the home. The best tube amps are also capable of that. If an amp succeeds as a "wire with gain", there's no reason why it should sound any different than any other audibly transparent amp.
When you talk about second order harmonics, you're talking about a different purpose altogether. In that case, you are deliberately designing an amp to NOT be audibly transparent. Some specialty amps are designed to add distortion or response imbalances to the signal in an attempt to "sweeten" the sound. For me, adjustments like that are better accomplished by digital signal processing. With a DSP, you can fine tune the coloration exactly the way you want it. With a colored tube amp, you're stuck with whatever signal distortion is hard wired into the design. That's why you see tube amp fans who have six or eight amps that they swap in and out, or they keep churning- buying and reselling amps- to try to find a perfect coloration for them. It's a LOT more efficient and inexpensive to just adjust a dial exactly the way you want it digitally. But there's a certain degree of fetishism to tube amp collecting that has nothing to do with sound quality.
Yes a tube amp can sound just as transparent as a solid state amp, and a solid state amp can sound just as distorted as a tube amp. But I don't know why anyone would go to the added trouble and expense to get a transparent tube amp when solid state ones are cheap and just as clean... and I don't know why anyone would want to buy a tube amp that is distorted with no way to adjust it.
That was really good. A candidate for another Sticky.
What comes to mind though are the Conrad Johnson Premier and the Mark Levinson ML-2 amps that were chosen for the "Challenge". They were highly regarded but each allegedly had a unique non SS sound signature which leads me to the question of transparency.