tube suggestions.. jcm800

[mchn13]

I have a 2203, my other guitarist in my band has a 2204. The guy we bought his from had kt88's put in it( not sure if you have to change a resistor to do this, or if its just a bias), but it sounds killer. Real open sounding. I love mine as well, but the el34's ar definitly a little more congested, or boxy in the mids..
Looking for a similar result, but maybe a little different.. was thinking of kt77's in mine.
Will it give me a similar result, or should I just go to kt88's as well?

 

[steve_k]

Try 6550's. A little less glassy than the 88's, more bottom end and they are a drop in replacement for the 88. The 77's are a drop in for 34's and yes, you will have to piggyback another resistor to get the bias in range for 34's or 77's.

Steve

 

[Schaf]

I wouldn't expect a huge change. The 6550's are are going to have a little rounder bottom and the highs will be a little more brittle. The 34's sound warmer and not as harsh. With that said, My keyboard player as a 2204 with 6550's and I can dial it in to sound almost exactly like mine with el34's. My preference is the 34's. But either will work.

Schaf

 

[Neeklaus]

I have a 2203, my other guitarist in my band has a 2204. The guy we bought his from had kt88's put in it( not sure if you have to change a resistor to do this, or if its just a bias), but it sounds killer. Real open sounding. I love mine as well, but the el34's ar definitly a little more congested, or boxy in the mids..
Looking for a similar result, but maybe a little different.. was thinking of kt77's in mine.
Will it give me a similar result, or should I just go to kt88's as well?

cool shit man, I hope you can bring on of these to the ampfest!

 

[mchn13]

Try 6550's. A little less glassy than the 88's, more bottom end and they are a drop in replacement for the 88. The 77's are a drop in for 34's and yes, you will have to piggyback another resistor to get the bias in range for 34's or 77's.

Steve

Mine has el 34's in it now. Are you saying the 6550' have more low end than the 88's? Sorry I don't know shit about tubes other than what's supposed to go in there... that, and his sounds awesome with the 88's...

 

[mchn13]

And do you have to add the resistor for the 88's or the 6550's

 

[mchn13]

I have a 2203, my other guitarist in my band has a 2204. The guy we bought his from had kt88's put in it( not sure if you have to change a resistor to do this, or if its just a bias), but it sounds killer. Real open sounding. I love mine as well, but the el34's ar definitly a little more congested, or boxy in the mids..
Looking for a similar result, but maybe a little different.. was thinking of kt77's in mine.
Will it give me a similar result, or should I just go to kt88's as well?

cool shit man, I hope you can bring on of these to the ampfest!

We might bring both. Ryan my other guitarist wants to come too. There real similar amps, but side by side you can hear the diff in the power tubes.

 

[Neeklaus]

awesome dude, the more the merrier, I think that will be a lot of fun to play those two back to back.
besides the fact I've never played a jcm ever...

 

[mchn13]

The 2204 has gold lions kt88' in it if that matters. I was thinking about getting a retube kit from eurotubes. Any suggestions?

 

[Shawn Lutz]

I prefer 6550's in 2203's myself and yes, you'll need the resistor change when going from EL-34's to 6550's. Classic metal tone with a SD-1 in front of 2203 w/6550's and loud as fuck

 

[mchn13]

Ok, as im reading it; if my amp has el34's, I can go to kt77's without a resistor change. If my amp haas 6550's I can go to kt88's without a resistor change.?
Just trying to work this out before I take this to my local tech. He'll fix it however I ask him to, and fast, but doesn't like doing shit where he has to research it lol

 

[Dale B]

Ok, as im reading it; if my amp has el34's, I can go to kt77's without a resistor change. If my amp haas 6550's I can go to kt88's without a resistor change.?
Just trying to work this out before I take this to my local tech. He'll fix it however I ask him to, and fast, but doesn't like doing shit where he has to research it lol

Right... Some KT77's, the JJ's in particular, may draw higher amounts of natural plate current, so the resistor change might be necessary for those as well. It just depends on the range/sweep of the bias pot. I was able to put GE 6CA7's in an older JCM 800. The set I had drew a pretty good bit.

If you go with KT88's, your tech needs to swap the bias resistor to 47K. He will also need to move the negative feedback wire to the 4 ohm speaker tap. It's the purple wire. I always keep mine soldered to the 4 ohm pot because I like a dirtier sounding amp.

One other thing to note is the preamp will kind of "brown" (aka lose headroom) when you make the swap to KT88s because the KT88s will be loading down the PT more than EL34s. This causes the preamp voltages to lower. You may notice it, but you may not because the headroom of the power section will increase. It's a combination effect, but it's definitely a cool one. To me, KT88s feel a little softer to the touch compared to EL34s.

 

[mchn13]

Cool, thanks man. Im leaning towards the 77's. My local fixes my amp real fast, but bitches if I make him do anything not stock lol

 

[blackba]

The 2204 has gold lions kt88' in it if that matters. I was thinking about getting a retube kit from eurotubes. Any suggestions?

I would e-mail dougs tubes. Doug has more tubes to choose from when recommending than just JJ's.

 

[mchn13]

The 2204 has gold lions kt88' in it if that matters. I was thinking about getting a retube kit from eurotubes. Any suggestions?

I would e-mail dougs tubes. Doug has more tubes to choose from when recommending than just JJ's.

Cool, thanks. My roomate got a retube kit for his ampeg v4 from him and was happy with it..