Tube amps... what is so great about 'em

Hi There,

My two cents:

I've had home and heard in other people's systems that I was quite familiar with some very good transistor gear. In some respects the best of it did some things better than my tube and tube hybrid toys. The best of solid-state seems to have a lower noise floor which allows you to more clearly make out those tiny details (chair squeeks, subway rumbles, blah, blah...). Pretty neat.

However, I've yet to hear a s.s. amplification chain flesh out the players/singers/instruments in my room the way that good tubes seem to. Everything you do hear is much more present and dimensional. Now don't get me wrong, not all tube gear gets it right. There is at least as much badly designed tubes as crappy s.s. out there. But comparing best-to-best, tubes just seem to create a more believable sense of "thereness" for me. As a result, I'm willing to put up with their idiosynchracies (heat dumped into the room, tube replacement, etc.).

Happy Trails!
Vince@Freewheel

Like Wirehead I'm a fan of space-tech labs. the most simple answer to your questiong i've ever found is written by albert on space-tech's website which i'll post below. you can read more easy-to-understand comments about tube gear at space-tech-lab.com

Q1. Why tube sounds better ?

Ans :

There are several main reasons that makes tubes sounds better , the following list out those points,

1. Tube is a much more linear device than transistor during operation.

2. Due to the highly non-linearity , conventional transistor amplifier must have very heavy NFB (negative feedback ) to make it work stablely, but tube amplifier can work well with very little or even no NFB, and heavy negative feedback is well known today as one of the main reason of poor sound quality.

3. Tube is a totally mechanical device, inside a tube is just some metal plate arrangements, the effective operation area is much much larger than a semiconductor (sometimes even 1,000,000 times larger). Almost every gold-ear audio engineer should knows , when music signal pass through a very small area, it will implies certain squeeze feeling to the signal itself and it is very audiable , so when a signal just pass through one transistor, you will immediate sense the compressed , flattened and hardened feeling from the music. The more transistors , it kills the easiness more and give your more flatness and hardness to the music.

4. Tube-amp has higher THD (total harmonic distortion) than transistor-amp by testing, but those THD created by tube-amp is all even harmonics which is very pleasant to ear and will not feel disturbing unless it is > 12% . But transistor-amp gives out odd harmonic distortions which is highly un-pleasant to human ear, by actual experiment, just 0.2% of odd harmonic distortion is audible and will create un-pleasant feelings even to un-trained ear.

Kubla, thanks for reminding us of Albert's great post. He only forgot one thing: Transistors don't glow romantically in a midnight session! (-: Cheers,

Agree pretty much with the previous posts and add that I like the ability to change the sound by swapping different tubes. It can be as expensive a pursuit as you'd like to make it but - the irony! - customizing the sound via tube-rolling is a bit of modernity that solid state can't touch. My experience has been that in a well designed circuit tube gear is very reliable, though not as maintenance-free as solid state. Ever notice how most superlatives heaped upon a given transistor device will include "very tubelike" when gauging the realism of the music reproduction?

I remember something Tim de Paravicini said. Tim is the noted designer of both tube and solid state equipment. He claimed that in properly designed circuits tubes should be indistinguishable from solid state, and vice versa. To back up his claim he manufactured a tube and solid state version of the same amplifier (under the EAR/Yoshino brand). At its worst, some of what people love about tube equipment is coloration. It's pleasant sounding, but it's still colorations. BTW, the same can be said about certain aspects of solid state sound (particularly the super tight bass). I've own or have owned a decent variety of tube equipment (Audio Research, Moscode, Counterpoint, Revox, Quicksilver, Sonic Frontiers) and I've come to the conclusion that tubes are totally cool, but at the same time, there's nothing magical about them.