Would a head with 6L6 or 5881 power tubes be easily rebiased for EL34's?

[Young Angus]

I know pretty much that it would be a pain and a silly idea to try and put EL34's into my savage 120, but i dont wanna touch that anyway. Just hypethetically speaking, with some of the other ENGL heads which sport 5881 and 6L6 power tubes (four of them), would they be easily changed to EL34's?

 

[Norman_T]

I am no expert in this but there is something called "Yellow Jacket Tube Converters" that THD make. Apparently they can convert any power tube to EL34s and don't need re-biaising. See the link below:

http://www.thdelectronics.com/

Norman

 

[Jeff_H]

My Marshall JCM 800 came with 6550's originally. I had it converted to EL34's for less then $90 - including power tubes. You have to change some caps or resistors or something I don't really understand, but it is a very simple process that is easily reversed.

I almost got rid of my 800 because I disliked the 6550's in it so much. Now it's so much better. That Engl was such an investment, it might be worth it to spend $100 to have it converted to see if you like it better. It can always be put back to stock.

 

[Marcel]

I am no expert in this but there is something called "Yellow Jacket Tube Converters" that THD make. Apparently they can convert any power tube to EL34s and don't need re-biaising. See the link below:

http://www.thdelectronics.com/

Norman

to EL 84 i think

 

[Duke of Metal]

Re: Would a head with 6L6 or 5881 power tubes be easily rebiased for EL34's?

I know pretty much that it would be a pain and a silly idea to try and put EL34's into my savage 120, but i dont wanna touch that anyway. Just hypethetically speaking, with some of the other ENGL heads which sport 5881 and 6L6 power tubes (four of them), would they be easily changed to EL34's?

You should be able to rebias it to be able to take EL34s. I mean, with ENGL amps and high quility built, i am sure they would have put a bias pot in there. All you need is a digital multi-meter and a bias probe to get an accurate reading for bias.

I my self always liked 6L6s over EL34s.


Duke

 

[Gearjoneser]

That's a question for ENGL's customer service.

You can easily mod an amp to go from 6550's down to EL-34's,
but many 6L6 amps can't be rebiased up to EL-34's, because
the transformer wasn't made to handle the added voltage/current. Some can. Some can't, usually depending on if the tranny can handle it. Personally, I think an ENGL might
really sound great with EL-34's, so I'd look into it by contacting them.

 

[Young Angus]

I know i rekon they'd sound great with EL34's too, only thing is that my Savage only has two KT88's, not four, so i wouldnt be able to put more than two big power tubes in it......i think thats how it would work anyway.

 

[Chi3f]

angus if you figure it out make sure you post here how it goes i like what i see from their site but have no way in testing it and i don't want it if i can't put in EL34's

 

[Duke of Metal]

I know i rekon they'd sound great with EL34's too, only thing is that my Savage only has two KT88's, not four, so i wouldnt be able to put more than two big power tubes in it......i think thats how it would work anyway.

I believe KT88's are sorta higher in wattage. Thats why you need less for the poweramp section. I could be wrong but I think they push 45watts to 50. while EL34s only push 25watts, 6L6s push 30watts, EL84 push about 12 watts or so.

If anybody can correct me, please feel free to.


thanks,
Duke

 

[Al.C]

I had a Mesa MK 1 modded to properly take EL 34's. It just involved changing out 4 grid resistors, I did it myself (with advise from boogie). A tech could do it very cheaply as it was very straightforward. I also installed an adjustable bias resistor. Best thing about the mod is you can easily go back to the original tubes by just re-biasing. The larger resistor does not affect the tone with the 6L6's.

 

[idsnowdog]

Usually a good tech can substitute any power tube without a major rewire. I have read that Jimi Hendrix had 6l6's in his Marshalls. Also Eric Clapton had kt66's in his Marshalls during the Cream era. Some amps allow you to switch multiple power tube configs with minor adjustment. The biggest mistake I see people make when they go to tube gear is fool themselves into believing that modding their gear is "too expensive". When you consider that the tubes can last three years with heavy use $100 isn't a bad investment. Both me and a friend of mine recently thought back about all of the good gear we ditched because we thought getting a good setup would be too expensive.

Snowdog