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Tube Amps Suck. Rant Mode On.


 
3/15/2006 10:51 AM
regis
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Tube Amps Suck. Rant Mode On.
Tube amps suck. I'm gonna sell all my vintage tube crap and get a solid state modeling amp.  
 
Here's what happened (Warning, major bitching to follow):  
 
I finally wore out the EL34 power tubes in my Traynor YBA1-A's. They lasted just short of two years of me diming them and pushing them hard. I was using the SED old Svetlana tubes and liked them a lot. Before they wore out they sounded great... Great crisp cleans aka SRV and killer overdrive aka whomever when pushed with a pedal overdrive.  
 
So I bought the same brand again thinking it would be the same. Not. These new tubes break up a LOT sooner than the old ones. Also, there was some kind of fizz way up in the high end that drove me nuts. I checked the bias THREE TIMES to ensure it was correct.  
 
I called the place I bought them from but didn't get much help, they were a matched quad and within spec, that is, three of them were within 1 ma, and the fourth was within 5 or 6 ma. More on that later. I couldn't send them back because they had been scratched by the tube socket holders.  
 
I went and talked to my tube amp repair friend here in town and ended up buying a quad of JJ's. They sounded like ass too. I know what you're thinking, something wrong with the amps or speakers, right?? I was hoping that was the case. No, I took the amps to my buddy who did a thorough check and only found a couple of scratchy pots. He also retensioned the tube sockets. I ran a couple of other amps known to be good through the speaker cab and it's fine too.  
 
We rechecked and tweaked the bias on the JJ's and I sold the SED's to a friend of his. I'd bet anything if I had returned them and gotten another set it would have sounded different yet again. I'll give the JJ's a chance but they don't have quite what I want. My bitch is that this happens almost every time I change power tubes, staying with the same brand. I guess it's too much to ask to have the same brand sound the same from one batch to another.  
 
About the matched thing, bullshit. I have NEVER bought a quad of so called matched tubes that were all within 1 or 2 ma of each other. The venders say 5 or 6 ma is within spec, I say baloney, two tubes 6 ma apart are not fucking matched. Was it like that back in the day with RCA's, GE's, Sylviana's?  
 
Ok, I'm not gonna sell my stuff and buy a modeling amp, but at least they have consistancy.  
 
Rant mode off, thanks for letting me vent.  
 
Regis
 
3/15/2006 11:39 AM
Satamax
email

Hi everybody!  
 
Regis, i think the best is to go through sets of power tubes untill you find the ones you like. Then get them measured on a good tube tester. Then reccord that for future use, i mean transconductance, mhmos, interelectrode cappacitance etc. That would help you in the future to choose your tubes. If you want a tad cleaner tube, may be go for a propper 6CA7.  
 
Bye.  
 
Max.
 
 
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3/16/2006 12:07 AM
Erik Miller
Curious, Regis: was your recent purchase new "Svetlana" tubes or "Winged C?"  
 
The Svetlana name was bought by E-H/New Sensor/Sovtek, they sell Reflektor-made tubes under that name, and that the tubes that used to be sold under that name now go by "Winged C."
 
3/16/2006 5:34 AM
regis
Curious, Regis: was your recent purchase new "Svetlana" tubes or "Winged C?"  
 
They were winged C seds.
 
3/16/2006 4:03 PM
Erik Miller
Do you still have the SED's that you liked so much? If so, do as much as you can to characterize them; i.e. check them for current draw, transconductance, etc.  
 
(ducking) Aspen Pittman has it right when he says that if you want consistency, you have to test the s#!t out of every parameter.  
 
Lots of things could be causing the "fizz." As someone else said, a parasitic oscillation is one possibility.  
 
It's also possible that the old tubes were masking an undesirable characteristic elsewhere in the amp or signal chain that the new ones emphasize. I have a Tele that, if played through certain combinations of tubes, has some annoying fret buzz on the 5th string.  
 
Now, that buzz is always there, but the "good" tubes mask it.  
 
Good luck....
 
3/15/2006 12:16 PM
jaysg
quote:
"Was it like that back in the day with RCA's, GE's, Sylviana's?"
Back in the day, nobody ran matched sets in guitar and bass amps. You went to the Lafayette store, bought new tubes, and put them in yourself. HiFi guys bought matched sets...but only the cork sniffers. Iirc, you can blame AH Pittman for all this matching stuff. O'Connor deserves some credit for the notion of putting an individual bias on each output tube. He basically says, 'while staying in a safe range, tweak 'em until you like the sound - they probably won't be matched when you're done.'  
 
Good luck in your search for better EL-34's.
 
3/15/2006 1:04 PM
Steve A.
email

regis:  
 
    Going from tube amps to modelling amps... how about something between those two extremes?  
 
    Have you looked at the Crate PowerBlock? 150 watts under 5 pounds, with a street price of $200.  
 
http://www.crateamps.com/html/product.cfm?pid=119  
 
    Although they are usually used with a multi-FX processor, I plugged straight into one at a jam last month and it had a nice strong clean sound. SRV liked having a lot of clean power so I think he would have liked it...  
 
Steve Ahola
 
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