Should I upgrade my power tubes ?

[Readheads]

I have a Rogue Audio Magnum II which is 100 Watts per channel paired with Vandersteen Treo CT speakers. My tubes seem to be shot as suddenly I get no amplification (just very low level audio). The 4 power tubes are TUNG-SOL KT120. I have been reading about getting "better" tubes but every discussion seems to get into "depends how you like the sound" types of comments similar to every other audio component - LOL.

So what's a man do ?

 

[abacus]

If the Tubes are shot, (It could be a fault elsewhere) then ask yourself the question, Are you happy with the sound you have been getting up till now, if yes buy the same, if not read up on how the various tubes change the sound and choose one that leans to what you are looking for.

Bill

 

[TrevC]

Your tubes are probably not shot. Get an expert to fix it.

 

[Al ears]

Your tubes are probably not shot. Get an expert to fix it.

I agree with TrevC, get it professionally checked out as it is highly unlikely that all tubes will fail at the same time. You might at least check your fuses and the bias of the tubes.

 

[daytona600]

Agree get the amp checked if okay replace the KT120 or some amps can accept the KT150 as well

 

[damonster]

I have a Rogue Audio Magnum II which is 100 Watts per channel paired with Vandersteen Treo CT speakers. My tubes seem to be shot as suddenly I get no amplification (just very low level audio). The 4 power tubes are TUNG-SOL KT120. I have been reading about getting "better" tubes but every discussion seems to get into "depends how you like the sound" types of comments similar to every other audio component - LOL.

So what's a man do ?

If you take it to a specialist they may be able to supply you with matched tubes and will be able to setup the bias properly for you. I took my tube amp to a specialist and said the tubes in it were poorly matched and I had burnt out a couple of capacitors. When it came back to me it sounded so much better and worth the outlay in my opinion.

 

[Al ears]

If you take it to a specialist they may be able to supply you with matched tubes and will be able to setup the bias properly for you. I took my tube amp to a specialist and said the tubes in it were poorly matched and I had burnt out a couple of capacitors. When it came back to me it sounded so much better and worth the outlay in my opinion.

Wise words.
In my opinion if you don't start off with a matched quad of tubes and don't know how to set up bias yourself then maybe tube amps aren't for you.
However, the OP hasn't mentioned that he can't and indeed hasn't replied yet.
I am intrigued as to why he thinks all his tubes have failed when they can be easily tested. The issue that they have all failed simultaneously confuses me.

 

[damonster]

Wise words.
In my opinion if you don't start off with a matched quad of tubes and don't know how to set up bias yourself then maybe tube amps aren't for you.
However, the OP hasn't mentioned that he can't and indeed hasn't replied yet.
I am intrigued as to why he thinks all his tubes have failed when they can be easily tested. The issue that they have all failed simultaneously confuses me.

I bought my amp being told it was self biasing. Specialists said that they still need setting up to the tubes. Even if one tube is out of sync not matched it will put strain on the others and could cause the caps to burn out.
My amp came back sounding the best I'd ever heard it. All caps replaced 4 new tubes Being charged just over £150 was worth the outlay for me. I will take it back next time I change tubes just to know its done properly.