Tubes Distort!

charlyg · Post by **charlyg** » Sat Jun 11, 2005 7:39 am

That warm pleasant sound coming out of your speakers through a tube amp is really distortion. Most won't admit it, but it is. It may "sound" sweeter or (pick and adjective) but it is not as true to the orignal as a highly sampled digital signal. Now if the tube fans would acknowledge this, it wouldn't be as big of a deal, but they never seem to. And yes there are some unpleasant side effects to digital sampling, I'm just talking about the waveforms. I use the same kind of reasoning for distorting the input of a power amp, not the output!

rictified · Post by **rictified** » Sat Jun 11, 2005 8:06 am

Most people can't hear distortion under about 1%, hifi is generally accepted to be 0.5% and under. A tube amp is only distorted at it's max rated output and then it is qualified. Such as 100 WRMS@ 1% harmonic distortion and then maybe this same amp could put out 130 WRMS@ 10% distortion. It would probably put out 50 WMRS @ .05% distortion. A SS amp on the other hand will distort very quickly over it's rated power. A tube amp at the same power rating can usually put out a lot more power than a similarly rated SS amp. Tube amps have much more head room than SS amps of the same power rating usually because of the gentle distortion curve. Mac tube amps are rated at 0.5% distortion at their rated output and are crytal clear.

Also odd even harmonic distortion (tubes) (1st, 3rd, etc.) is generally accepted as being pleasureable as compared to even order distortion (SS)(2nd, 4th etc.) why? who knows.
But with any amp you are almost always playing way below it's rated output, if you really thump the E string you might get momentary full output but that is not usual unless you are playing so loud that the amp sounds like a Marshall on ten.
Why they sound so much more full at all volume levels, no one knows that either. Meters don't always tell the whole story.

jnbass · Post by **jnbass** » Sat Jun 11, 2005 8:32 am

ya know I've seen SS amps that try to emulate valve amps-but I've never seen (so far) a valve amp with a SS setting.

Solution-buy both!

charlyg · Post by **charlyg** » Sat Jun 11, 2005 10:22 am

Ny theory is, that's because you can't "clean" up the tube signal enough to make it that "sterile" digital sound.

PS. I'm just havin some fun with this. Sound is subjective to each listener, and has been pointed out the tube distoritons sound better to the human ear!

clankchris · Post by **clankchris** » Sat Jun 11, 2005 2:05 pm

I just played through my Hartke Kickback 15 instead of my Mesa Boogie today, and I can't believe that I've "suffered" through it for so long.
I prefer my Rickenboogie over my Hatkenbacker for sure!

clankchris · Post by **clankchris** » Sat Jun 11, 2005 2:07 pm

Uh, Hartkenbacker, I meant?

soundmasterg · Post by **soundmasterg** » Sat Jun 11, 2005 2:07 pm

Bob, you've got the type of distortions from each device backwards. Tubes usually generate more even order distortions when clipped, and transistors generate more odd order stuff. The even order distortions reinforce the fundamental signal, making it louder, whereas the odd order distortions mask the fundamental, making it quieter. Read this paper on this site and it will explain better than I can. You can just breeze over the math unless you really feel like studying it!

The part about the distortions is down towards the bottom.

http://www.milbert.com/tstxt.htm

My thoughts about tubes distorting is who cares! If it sounds good, I use it. If it doesn't I don't. As simple as that!

jnbass · Post by **jnbass** » Sat Jun 11, 2005 2:21 pm

Lord Valve!

charlyg · Post by **charlyg** » Sat Jun 11, 2005 2:22 pm

Ya, but what's the fun in talkin bout dat?

rictified · Post by **rictified** » Sat Jun 11, 2005 9:13 pm

Yeah you're right Greg, I get stuff like that backwards all the time. I went to school for this stuff 20 years ago and only remember the principles for the most part anyway, I've forgotten many of the details. And actually even though odd and even harmonics are fact the sound differences as a result of them are theory I believe. I don't fully accept the theory as it doesn't explain why tubes still sound better at low volumes, I think it may be one of many reasons they sound different.

I sent the Almighty Lord an anti-Bush thing one day (wasn't that bad, was a move on.org petition I think) you wouldn't believe the scathing Fascist letter I got back from him, he was going to report me to my ISP etc. The letter he wrote made Dick Cheney look like a nice, friendly liberal. Taught me a lesson though, I'm careful who I send them to now.

soundmasterg · Post by **soundmasterg** » Sun Jun 12, 2005 1:12 am

Thats funny Bob. Well it just goes to show you that you can't talk politics in public without getting someone annoyed!

rictified · Post by **rictified** » Sun Jun 12, 2005 5:28 am

Yeah, you are right although I get what I consider junk mail all the time and I just delete it, and I'm not saying he didn't have a right to write me back and tell him to not send him anymore stuff like that like one other person I know did, haha!, but the tone of his letter was unbelievable.

jps · Post by **jps** » Sun Jun 12, 2005 6:27 am

You should report him to his ISP.

jnbass · Post by **jnbass** » Sun Jun 12, 2005 8:45 am

its the passion...

rictified · Post by **rictified** » Sun Jun 12, 2005 1:36 pm

haha! no passion in his letter. I will try to refrain from expressing my opinion of him in public however. Hey, how do you spell fascist anyway?