New Valve Recommendations Please

Davearl · Posted: Fri May 19, 2006 12:31 am Post subject: New Valve Recommendations Please

Hi,

I have a JCM 2000 TSL 122 that has developed a whistling noise. I assume i'm going to have to replace the valves.

Any advice on the new ones to put in, Can i do it myself, how much are they etc.

I play a Gibson Les Paul Standard through it and play anything from The Clash to The Kaiser Chiefs, so don't need a demon metal sound, just full on valve overdrive.

Cheers,

Dave.

mccabre · Tadpole Joined: 05 Jun 2006 Posts: 18

Hey, this is no problem - sounds like you have a bit of microphony from old valves... just wear and tear!

What you need to do is look at the model number on the glass valves (the output valves are what will need replacing... big ones). Then simply go to any shop that sells valves, give them the model number and they'll give you the valves.

Once you get them, it's simply a case of lifting the old valves out of their base plate and slotting the new ones in.

Obviously, when you change them the amp should be off and DON'T touch anything else in the amp... you could get a rather serious electric shock!

Once the new ones are secure, put the amp on standby for about 10-15 minutes (if you switch an amp on straight away, the heat shock could crack the glass casing on the valves) and play away!

If you feel uncomfortable doing this, just take it to your nearest tech who should be able to do it in front of you if you supply the valves (otherwise they take their sweet time!).

Go to www.watfordvalves.com - Harma valves are brilliant and last a lot longer then G.Tubes or Electro Harmonix!

C

Davearl · Posted: Wed Jun 07, 2006 3:05 am Post subject:

Thanks for that Friend.

Will i need to get the valves "Biased" and what does that mean?

Cheers.

pizza8guy888 · Little Hamster Joined: 17 Jun 2005 Posts: 77 Location: NJ

If you change your tubes with the exact same tubes already in the amp, you should not have any serious biasing problems. However, if you want to experiment with new tubes, a re-biasing is a must.
Biasing a tube amp is adjusting the power or voltage supplied to the tubes. If you do not bias, it can supply to much power to the tubes and have them run real hot which would decrease the tubelife and cause possible overheating problems. Sorry i know this post is somewhat scatterbrained and unorganized. I am at work right now...haha...and rushing it...best of luck with it and Im sure u will enjoy the sweet sound of new tubes.

Davearl · Posted: Wed Jun 28, 2006 1:31 am Post subject:

Thanks for that friend, i'll give it a go.