AmpTalk.com

[NinjaZX6R]

Hi guys,

My first post here, but I was wondering how to tell when an amp needs new tubes? My Peavey Triumph 120 has a few symptoms and I thought it might be tube related. It makes strange noises...not humming, but actual noises while it is sitting there doing nothing. Sounds somewhat silly, but a guitar doesn't even have to be plugged into it. It can just be on, and I will hear noises, somewhat like if you were to bump it and have the reverb tank move. Also, it doesn't seem as loud as it should be. I can turn the clean channel up to 6 or 7 and it isn't incredibly loud. This thing is 120 watts of all tube power, so I figured it would be louder than this! Is this possibly due to old tubes as well? Any insight will be greatly appreciated!

-Collin-

[khingpynn]

Hi and welcome I am new here too but this is not my first post.

You will need new power and preamp tubes when... you want them for different tones, or if there is a strong orange glow. There should never be more than a soft glow coming from small areas in the tube. Large plate sized glow is a indication of a blown tube.

You will need new power amp tubes you hear volumn going up and down or reduced volumn from the amp.
You will need new preamp tubes when there is non musical feedback or other noise.

Also if you observe a crack in the glass of a tube but it seems to work OK still... replace it... once it losses the vacume it will blow and you do not want that during use.

To help preserve you tubes always let your amp idle on standby to warm up for 1 - 2 minutes before turning the amp on. Similarily let you amp cool down while idleing on standby for a minute before turning the amp off.
NEVER suddenly/quickly turn your amp on and off... bad for tubes and really bad for the output transformer.
Know that biasing may be needed if you do not carefully pick the right power tubes for your amp ( some makers have a bias rating or go with a tube supplier who does.... preamp tubes self bias.
Never move a hot tube amp only move it after a thorough cooldown... if in doubt wait 5 minutes.
Remove tubes only with the amp is cool and mains power is disconnected.

Hope this helps.

Craig
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[rockon1]

khingpynn gave some good advice. To that I would add that noisy pre amp tubes can make pops and crackling noises.....Power tubes start to loose low end response first as they get old and also power output and may sound weak or dull..... At any rate how long have they been in the amp? If you dont know because the amp is new to you I'd definately replace them.When ever I buy used tube amps I replace all the tubes as I have no idea of their history-Bob