# JCM800 tubes



## generic (Feb 4, 2008)

Hi all, I've got a 85 Marshall JCM800 2204 and it desperately needs new tubes (EL34) and a rebias. Anyone have any advice on the best tubes to get for a higher gain type of sound? I was thinking Groove Tubes might be good, but I really don't know for sure.

Thanks in advance!


----------



## Lemmy Hangslong (May 11, 2006)

I always preffered Svetlanas in my JCM 800. They have a complimentary tone to the 800 IMHO... not to harsh, nice and wide with good girth.

You should also consider JJ EL34 and EL34L. The EL34L will get you in that punch 6L6 zone while maintaining that EL34 wall or tone sound.

5751 preamp tubes always sounded cool in my old 800.

As for biasing just follow the recommended proceedure using a multi meter ior biasing meter and aim for the middle of the working range. Once you get it there have a listen then go up and down a mv or so in each direction and let you ears be the judge aas to what sounds best.

If you use a scope get the sine wave as close to perfect as you can then do the volt up volt down and again use your ears to fine tune the tone.

Cheers
Craig


----------



## Tarl (Feb 4, 2006)

+1 on the JJs.....great reliable and toneful tube and a good price.


----------



## Guest (Jun 25, 2009)

Get a set of tubes, whatever you want , more money doesn't mean better. They pretty much all come from the same places. I'm not big on Asian tubes, but they are cheaper, sound fine, but may not last quite as long, glass thickness has been an issue. A bias adjustment is probably not needed and rarely is. You can go cold for longer life or hot for shorter and unless your really blasting the amp your not going to hear a whole lot(or any) of difference. Your amp is probably set in the middle and should stay there. THere is a lot of myth out there surrounding tubes and biasing and of course some folks have special hearing and can detect all of that. I don't. My distortion analyser doesn't either, nor does my spectrum analyzer, but some very special people do. Groove tubes, JJ's, Sovtecks will do fine, but shop around.kkjuw


----------



## Emohawk (Feb 3, 2006)

Depends on what you're looking for. 

I currently have JJ KT-77's in my 2204 clone. Less compressed than most EL34's, and a touch darker (generally the case with JJ tubes of any type that I've tried).

I had Svetlana EL34's in there for a while. More compressed & a bit more "crunchy".

Before that it was EH EL34's. I was never in love with them, but they were old tubes from my GH100TI so they may not have been at their best.

I haven't tried Asian EL34's so I can't really comment with any degree of accuracy. I expect they'll be a little edgier/brighter, but that's purely based on experience with other Asian tubes I've used.

On thetubestore.com they have a review/comparo article about EL34 type tubes. Might be helpful. Here's a direct link. http://thetubestore.com/el34review.html


----------



## Ripper (Jul 1, 2006)

The latest Shugang EL-34's are really really good sounding tubes, they last very well and I've had no problems with them, the asian tubes have come along way and are constantly bettering the products.


----------



## Guest (Jun 25, 2009)

Asian tubes getting better doesn't surprise me. Its like everything else. I say buy a set or two if youcan afford them and go with them. Of course check with the folks with the golden ears to verify that the right amout of compression and tone coloration is present. My expensive instruments can't detect that.:bow:


----------



## Guest (Jun 25, 2009)

Emohawk said:


> Depends on what you're looking for.
> 
> I currently have JJ KT-77's in my 2204 clone. Less compressed than most EL34's, and a touch darker (generally the case with JJ tubes of any type that I've tried).
> 
> ...


A touch darker, crunchy , sounds like a recipy for special brownies.9kkhhd
A set of JJ's and a six pack of Bud light does it for me.


----------



## Guest (Jun 25, 2009)

KHINGPYNN said:


> I always preffered Svetlanas in my JCM 800. They have a complimentary tone to the 800 IMHO... not to harsh, nice and wide with good girth.
> 
> You should also consider JJ EL34 and EL34L. The EL34L will get you in that punch 6L6 zone while maintaining that EL34 wall or tone sound.
> 
> ...


Good girth eh! I got a compliment like that a few nights ago. I think wifey was trying to cheer me on.kksjur


----------



## Lemmy Hangslong (May 11, 2006)

Lol... a little cheering on goes a long way!


----------



## EL34POWER (Jan 16, 2007)

"C" in the power section. NOS RFT in V1. Tung Sol in V2,3.

And yes have a look at the tubestore. They usually have them all. Including the RFT.


----------



## dwagar (Mar 6, 2006)

JJ E34Ls work for me.


----------



## stompy (Jul 7, 2009)

My good friend has Ruby 6550's in his JCM 800 combo, and its killer! Soo loud and amazing sounding.


----------



## Guest (Jul 10, 2009)

Its one of those things as you can see. Experiment. Something cheap of e-bay out of the Soviet blok might do it. I've been lucky that way.:smilie_flagge17:


----------



## Groupx (Oct 18, 2006)

A couple of simple preamp mods and you can have all the gain you need on these amps and you won't need to spend a nickel on tubes.
Search Google 'JCM 800 Mods Trace' there is lots out there


----------



## Caribou_Chris (Feb 15, 2009)

In my 800 I have JJ's in the preamp and Ruby EL34's in the poweramp. Sounds great to me. I may replace the Rubies with JJ 34's or KT-77's at some point, but I'm not in too much of a hurry there b/c the preamp tubes matter more in the tone of your distorted sound than the poweramp section does. Right?

Personally I think the type of tube (12AX7, EL34, KT77 etc) is more important in getting a certain sound than who made it. Although I'd go Slovak before China. 

My 0.02


----------



## TubeStack (Jul 16, 2009)

JJ E34Ls are cool, with JJ ECC83S in the preamp.


----------



## Joebob (Aug 4, 2009)

JJ's in the preamp of course.
If you can put a Mullard in V1, or put the most
high gain of your JJ's, of course you need a friend with a tube tester 
for that.

Power tube ,as far as i'm concerned Mullards goes
with Marshall, pricey but it's GREAT !!! perfect mids and
articulation. Lower budget i go with Svetlana's, the expensive ones.
Big fat low end, really tight.

Tell use what you decided...


----------

