In general, people will describe them as being warmer, and sounding more musical than a transistor amplifier. For the same amount of power, they sound louder as well. Basically, it's tricking your ears with the distortion, the distortion isn't harsh, so your ears percieve it as being louder and not as being sonically harsh. Tube amps produce even ordered harmonics, while a transistor amplifier produces odd ordered harmonics. Odd ordered harmonics are fatiguing, which is why good transistor amps must have low distortion to be tolerable, turn the volume up high on a poorly designed transistor amp and notice the screaming highs and nasty sounding distortion, it's very fatiguing and ear piercing at times, even at lower levels the music can get fatiguing on the ears. With even ordered harmonics like from a tube amp, the distortion is actually pleasing to the ear and isn't harsh, it doesn't scream like transistor amps, the music will sound a bit more "fat". Tubes also operate at very high voltages, and tend to have better dynamics and imaging than a transistor amp, depending on design of course (not saying a well designed transistor amp can't do the same for you). Very low bass (subwoofer range)isn't handled as well with a tube. The main downsides of a tube amp are that they aren't usually as sonically accurate(more distortion mainly), but very good designs (such as the one from US amps you're looking at) combat this problem and the distortion is extremely low. If a tube amp is poorly designed, it will sound slow and tubby. There is also the maintenance, tubes eventually go out and will have to be replaced, they'll usually last a long time, though, it just depends on how much you listen to and how hard you drive it. They can last years in some cases, it just depends on how hard you drive it. I was actually considering this amp before I ended up getting a JL amp for free , I auditioned it and the sound quality was top notch. US amps always has made a solid amp. The very best tube and transistor amps sound a lot alike, of course they still retain some of their general characteristics, though, and you should go hear the difference before buying.
, I auditioned it and the sound quality was top notch. US amps always has made a solid amp. The very best tube and transistor amps sound a lot alike, of course they still retain some of their general characteristics, though, and you should go hear the difference before buying.