A direct swap. Take out the one tube, put in the other.

The Disasternauts

I actually have a 6L6 in mine and I like it a little better than the 6K6. But that's just me, may not be for everybody.
-Paul

Paul
Atomic Mosquitos
Bug music for bug people is here!
Killers from Space

I's hard to describe, it just sorta opens it up a bit more. Not a huge difference or anything.
Who knows? It may just be my imagination and there may be no difference at all.
An amp tech recommended it once, and I tried it and liked it. I think I have a Ruby in there.

Paul
Atomic Mosquitos
Bug music for bug people is here!
Killers from Space

i wish i had this information a few weeks ago when i replaced the 6V6 tube in my reverb with another 6V6. it seems to have lost a little bit of its drip but at least the squealing noise from the bad tube is gone.

so another question. my deluxe reverb has a little bit of hiss from both the normal and vibrato side, but more so from the vibrato. this amp has been used on the average twice a day for four years and has the original tubes. when i plug the reverb into it the hiss increases greatly, especially on the vibrato side. none of the tubes are loose.

could i possibly need new tubes in the amp?

i tested a friends rca NOS tubes in it last year and the sound changed noticeably, for the good. should i go with the rca, or is there another tube that's better?

sorry, i can't explain myself better, but any information is helpful..

www.surfintheeye.com

stigger108
What is the average tube life, how hard are they to change? Any are there any warning signs that you tubes are going?

tubes failing have a variety of possible sypmtoms:

microphonics: something inside the tube fails causing the tube to act like a microphone.

shorts across the tube base can make sparks or even smoke! weird electrical fire burning smells...

leakage: the vacuum tube can fail and let in air...

weird colors...

weird sounds...cruchiness when none present before, pops, snaps, crackles...

weird distortion...howling sounds that you didn't intend your amp to make...

Most of the time, though, tubes just keep working...I have had a set of Mesa Engineering 12AT7 and 12AX7 tone tubes in my bassman since 1985...they still sound, and perform exceptionally.

Power tubes should be properly biased for longest life...

my advice, don't worry about new tubes...they will last a long time, and if something wacky happens to them, you will see, hear or worst of all smell something going wrong!

Carol,> momsurfing_

......
so another question. my deluxe reverb has a little bit of hiss from both the normal and vibrato side, but more so from the vibrato. this amp has been used on the average twice a day for four years and has the original tubes. when i plug the reverb into it the hiss increases greatly, especially on the vibrato side. none of the tubes are loose.

could i possibly need new tubes in the amp?

i tested a friends rca NOS tubes in it last year and the sound changed noticeably, for the good. should i go with the rca, or is there another tube that's better?

sorry, i can't explain myself better, but any information is helpful.

You explained yourself quite well. If only some of the dunderheads that come into my shop were so eloquent.

Hiss is indicative of eminent failure. This is usually accompanied by lower gain than formerly noted (you need to turn it up to get the same volume level). Not always, but usually so. I'd first suspect the pre-amp tube located closest to the power amp tubes - it's what we call the phase inverter, and is the only pre-amp tube in the whole circuit that is common to both channels. The tube type is the same as all the other small ones, either a 7025 or a 12AX7. It may be a 12AT7, that's fine too, they all interchange quite nicely.

I don't often recommend changing all the pre-amp tubes at once, just because one of them has gone bad - it's usually not necessary. If you do decide to change them all, do so for purposes of trying to achieve a different tone (better!), moreso than trying to stave off possible failure. You mention NOS RCA tubes - good luck finding them. Well, at a decent price, I mean. If you can, I'd say that you should buy from a dealer who will let you return the whole set if you don't like them (within a short time, obviously). I'd hate to see you stuck with tubes that don't make any difference, or worse, make a difference in the wrong direction.

You didn't mention them, but power tubes should always be replaced en masse, and the bias adjusted afterwards (if possible).

You, and every user that ever plugged into an amp, can change tubes yourself. You may not be able to adjust the bias, but you don't need to pay a tech just to pull out one tube and insert a replacement. Tubes are "keyed" - power tubes have a tongue sticking out of the center post that fits the socket only one way, and pre-amp tubes have an open spot between two pins that also fits the socket only one way. Unless you use a large hammer, you can't insert them incorrectly. (Well, yes, you could, but then the tube would be worthless - you just broke at least one pin.)

in re: your new 6V6..... perhaps you can return that for an exchange on a 6K6?

HTH

unlunf

MY RIGHT HAND IS FASTER THAN YOURS!
(copyright 2003, Bruce Welch)