I recently switched from a Marshall 8100 100 watt hybrid head to an all tube 50 watt Carvin X-50B head in the hopes of achieving a better live tone. Logicaly, the 50 watt tube head is superior, but, I still can't get a tone I like. I feel the sound is too "mushy" for my tastes. I go for a crisp, bright distorted tone with a really tight bottom. The kind that cleans up nicely when you roll back your volume knob. My main live axes are a 77' Les Paul Deluxe and a neck-thru B.C. Rich. And obviously, I have to re-tube the 50 watt Carvin. I am running groove-tube el-34s in the 50 watt and am thinking that replacing them with a pair of 6550s will do it. Or, maybe I'm just a Marshall man!

i think a good set of el34's and having the bias set properly should do the trick.

i have never had 6550's in a guitar amp (just my old svt) , but from what i know about them they have a lot of clean headroom before they saturate.

it also makes a difference how you get your distortion sound. do you crank both the preamp and power amp ? do you use a pedal or rack unit for the distortion ?

if you want your amps power tubes to distort/saturate , then the 6550's might not be your best choice.

do you like the way other el34 amps distort?
el34's tend to have a "soft" breakup.
maybe 6l6's are a better choice for the sound you want.
6l6 tubes are used in many peavey, mesa, and fender amps(to name a few)

i hope my rambling has been of some help.

the people at groove tubes might be able to help you make the right choice ....it couldnt hurt to talk with them.

I like 6CA7's in an amp that takes EL34's. The 6CA7's have a bigger bottom end that most EL34's and they have a better clean sound to my ears.

If you want to just stick with EL34's, take the amp to a tech and see if it's biased properly. That makes a huge difference.

I put KT88's in my JCM800 and it made a huge difference.
Just make sure the guy doing the work knows what the hell he is doing.
When you swap tubes, you are changing the 'demand' on your transformer. Transformers are expensive!!! Damage it and you will need a new amp.








_________________
Play what you want, play what you feel and don't look so suprised when the people you play for don't get it.

12ax7 wrote:

I put KT88's in my JCM800 and it made a huge difference.
Just make sure the guy doing the work knows what the hell he is doing.
When you swap tubes, you are changing the 'demand' on your transformer. Transformers are expensive!!! Damage it and you will need a new amp.

what was the difference exactly ?
i dont have any experience with kt88's, and am very interested in them.
i have el34's, 6l6's and el84's in my guitar amps (and 6550's in my bass amp).....do the kt88's really tighten up the bottom end ?
i know that marshall uses them in a few amps now....so there must be something to them.

thanks, Chuck

chuck wrote:

12ax7 wrote:

I put KT88's in my JCM800 and it made a huge difference.
Just make sure the guy doing the work knows what the hell he is doing.
When you swap tubes, you are changing the 'demand' on your transformer. Transformers are expensive!!! Damage it and you will need a new amp.

what was the difference exactly ?
i dont have any experience with kt88's, and am very interested in them.
i have el34's, 6l6's and el84's in my guitar amps (and 6550's in my bass amp).....do the kt88's really tighten up the bottom end ?
i know that marshall uses them in a few amps now....so there must be something to them.

thanks, Chuck

I wish I could just play it for you and let you decide for yourself!!!!:)

When I do palm-mutes it goes CHUNK-CHUNK like a sonofabitch! I kid you not, low-end that will rattle your man-seed!

KT88's can take plate voltages of up to 800 volts. They used to use them in High-Fi equipment years ago because they run cleaner than the 6L6's.
They are physically larger too. Fat funny-looking bastards.
The advantage: it gets the speaker cones to break-up a before the output stage of the amplifier does. I have Celestion G25's in my 4x12 and it was a big difference.

I think they do tighten the bottom-end up a bit. You will still have tube-sag, nothing but solid state will ever rid you of that.
But the TONE, you can eat off of it.








_________________
Play what you want, play what you feel and don't look so suprised when the people you play for don't get it.

12ax7 wrote:

chuck wrote:

12ax7 wrote:

I put KT88's in my JCM800 and it made a huge difference.
Just make sure the guy doing the work knows what the hell he is doing.
When you swap tubes, you are changing the 'demand' on your transformer. Transformers are expensive!!! Damage it and you will need a new amp.

what was the difference exactly ?
i dont have any experience with kt88's, and am very interested in them.
i have el34's, 6l6's and el84's in my guitar amps (and 6550's in my bass amp).....do the kt88's really tighten up the bottom end ?
i know that marshall uses them in a few amps now....so there must be something to them.

thanks, Chuck

I wish I could just play it for you and let you decide for yourself!!!!

When I do palm-mutes it goes CHUNK-CHUNK like a sonofabitch! I kid you not, low-end that will rattle your man-seed!

KT88's can take plate voltages of up to 800 volts. They used to use them in High-Fi equipment years ago because they run cleaner than the 6L6's.
They are physically larger too. Fat funny-looking bastards.
The advantage: it gets the speaker cones to break-up a before the output stage of the amplifier does. I have Celestion G25's in my 4x12 and it was a big difference.

I think they do tighten the bottom-end up a bit. You will still have tube-sag, nothing but solid state will ever rid you of that.
But the TONE, you can eat off of it.

*********************************************************

thanks for the info....
i will do the research, gather the info, and swap one of my amps over to kt88's.
i am currious now....and wont be able to NOT try it !

thanks again, and have a great weekend,
Chuck

Thanks guys! Maybe it is the biasing, but I bought the amp used and have no idea how old the tubes are. I prefer power-amp breakup over pre-amp but use a little of both depending on the room I'm in. I don't use a rack or pedals to get my breakup. I can switch down to 50% or 25% power on the amp, but that sounds even worse to me. My buddy has a JCM 900 and I love playing his amp.

Zito wrote:

Thanks guys! Maybe it is the biasing, but I bought the amp used and have no idea how old the tubes are. I prefer power-amp breakup over pre-amp but use a little of both depending on the room I'm in. I don't use a rack or pedals to get my breakup. I can switch down to 50% or 25% power on the amp, but that sounds even worse to me. My buddy has a JCM 900 and I love playing his amp.

You just have to do what is right for YOU when it is all said and done.

I hear you about the Output section break-up. Difficult to describe, but once you hear it you never forget it.








_________________
Play what you want, play what you feel and don't look so suprised when the people you play for don't get it.