Jump to content
Sign in to follow this  
jegarcia

DT25 Head - Replacing tubes

Recommended Posts

Hi guys.

 

How difficult is it to do this?. I just bought one of these units and I live in a country where there is no one that provides this kind of service. Shipping the head to the US for service would be extremely expensive both ways. I'm thinking that I should have bought something else.

 

Your comments would be most welcomed 

 

JG

Share this post


Link to post
Share on other sites

its no harder than any other tube amp.  BUT you must replace with the same brand and type of tubes (EH EL84 matched set).  Do not substitute JJ's or any other brand.

 

If you don't know what you are doing find a professional repair shop.  There are voltages in there that can kill you even when it is unplugged!  Any amp repair shop can change tubes and bias for you.  Here are the instructions for biasing both DT50 and DT25.

 

http://share.myflare.com/rtwSHH

  • Upvote 2

Share this post


Link to post
Share on other sites

If there are no guitar shops then a qualified electrician might help. Or someone used to dealing with old radios.

 

I did it with a friend of mine after we watched a load of YouTube vids. You will need a voltage tester that is well insulated.

 

If you don't know about these things it is not worth your life to play with it though!

Share this post


Link to post
Share on other sites

@ radatats

 

Thanks man. Very helpful post. After I posted I made a few calls and it turns out there is an authorized L6 dealer here.  They don't sell L6 amps but a tech there did say that if I bring the tubes (I went ahead an order a spare set of EH tubes) and the bias specs (which you provided) they can do the setup.

 

Feeling much better...

 

JG

  • Upvote 1

Share this post


Link to post
Share on other sites

@radatats why is it so important to maintain same brand of tubes and not change? Have nothing against EH tubes, but just bought myself a DT25 and not sure how many hours on existing original tubes.

 

Have a brand new set of matched JJ's sitting in my parts box and wouldn't mind using them if possible to save a purchase. Especially as I sold the amp I bought them for.  

 

Honestly never heard of having to use a specific brand of tubes with am amp. Is there a biasing problem or something?

 

Thanks 

Tom 

Share this post


Link to post
Share on other sites

@radatats why is it so important to maintain same brand of tubes and not change? Have nothing against EH tubes, but just bought myself a DT25 and not sure how many hours on existing original tubes.

 

Have a brand new set of matched JJ's sitting in my parts box and wouldn't mind using them if possible to save a purchase. Especially as I sold the amp I bought them for.  

 

Honestly never heard of having to use a specific brand of tubes with am amp. Is there a biasing problem or something?

 

Thanks 

Tom 

 

There are some threads on this forum about people, including me, who replaced the stock tubes with other brands (JJ's in my case) and shortly thereafter ran into serious problems.  I learned my lesson and will only use the recommended tubes.

  • Upvote 1

Share this post


Link to post
Share on other sites

@Just Startin'

 

The amp was designed with the recommended tubes and L6 only tests with their recommended tubes. While you may be able to get away with other tubes it is best to go with the L6 recommended set. As Gear Head pointed out you could have unpredictable results not to mention that if your amp is fairly new you may void the warranty.

 

Best

Share this post


Link to post
Share on other sites

@radatats why is it so important to maintain same brand of tubes and not change? Have nothing against EH tubes, but just bought myself a DT25 and not sure how many hours on existing original tubes.

 

Have a brand new set of matched JJ's sitting in my parts box and wouldn't mind using them if possible to save a purchase. Especially as I sold the amp I bought them for.  

 

Honestly never heard of having to use a specific brand of tubes with am amp. Is there a biasing problem or something?

 

Thanks 

Tom 

 

Yeah, somewhere back in the threads one of the technicians from Line6 got into the tube replacement conversation and explained that the amps were designed specifically to use EH tubes, and due to the nature of the power switching of the amp, other tubes present issues that can melt the circuit board, fry the amp, etc.

 

http://line6.com/support/topic/4713-replacement-tubes-recommendations/page-2?hl=tubes&do=findComment&comment=110463

 

http://line6.com/support/topic/13389-dt50-noise-floor-vs-dt25-noise-floor/?hl=tubes&do=findComment&comment=94862

 

http://line6.com/support/topic/15605-bias-dt-25-amp/?hl=tubes

  • Upvote 1

Share this post


Link to post
Share on other sites

radatats link is no longer valid - this video details biasing DT25 combo, which is similar to the head:

 

  • Upvote 2

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×