MV JCM800 vs. TW EXP

[rooster]

How many of you have done this shootout? I just did this today into the same speaker cab and came away with a feeling that the MV JCM800 is a better amp than I remembered. True it does not have the bass of an EXP, nor the touch sensitivity, but I can really tell that they are very close cousins. Yes, Drake trannys and all. You?

[fishy]

You are not alone with that thought. The JCM800s got dissed to some degree and a little unfairly in my opinion. They are great amps.

[Carlin Mitchell]

My 50 watt 800 was my favorite of all the amps I've had. I got it for 400 bucks and it had been spray painted pink with some rock bands logo stenciled on the sides. It was the ugliest thing ever, but it had the stuff. I'd go to our practice space on my lunch break just to turn it way UP when nobody was in the building. I've never played through an express so I have no idea what to compare it to but I loved my 800.

[johnny riff]

hi rooster
you are rihgt in saying the jcm800 is a great amp.I've biult 3 clones over the last 5 years (2 for friends 1 for me).but I have to say the express and the liver pool are much more responsive to a players needs when you don't want a lot of foot switches.It's all at your guitars vulume setting.that being said good, day to you sir.


Johnny Riff

[Fischerman]

If you ripped out the Master Volume on the Marshall (or just cranked it to '10' and left it there) they would seem to be somewhat similar (maybe even more similar to a Concorde but still pretty similar to an Express). Biggest difference would be that the Express/Concorde have the tone stack early in the preamp and the Marshall has it at the very tail end of the preamp. The power supply, PI, power section, bias are very similar.

[johnny riff]

Yes you are right,But the jcm has a CF and the express is plate loaded in the pre amp section.I don't know about the concorde.

[rooster]

Cool. I also meant to add that - oddly enuff - the JCM800 also has a permanent 500pf cap across the volume pot. Which is of course what you find on the extreme range of the TW bright switch......

[johnny riff]

I've had a long love affair with plexies,jcm's(early 80's version ect.)It's what got me into building tube amps.I didn't discover TW's until about 7-8 years ago.great simple design.I don't care for the tw's bright switch,I mostly leave the switch out and use 500pf in the VD.

[rooster]

johnny - Yeah, in regard to that bright switch that you don't really care for? Did you do it like Francesca or Kelly? I don't know if you caught that here a while ago in another post, but I did mine like Francesca and came to find out that the Kelly version was much better sounding. Frankly, I use the thing all the time now, actually depend on it in the gtr rotation department. It turns out that Glen also has the Kelly version on his original model, as well. It really doesn't seem like it would make that big as difference but I will testify that it does....

Well, I'm just saying you might take another look at it? Like you, I hated that switch when it was wired like Francesca.

[geetarpicker]

Yep, I can't live without the 500pf bright position in my original Express and the two clones I built of it. It somehow seems to add to the "clean to mean" range, as folks like to call it. With my amps the bright cap adds to the clarity when you back off for clean, but the amp tends to compress in the highs enough when you crank up that it then smooths out. It seems once the output stage (or PI?) is pushed the high end rolls off a bit. Also, the old 25s seems to add to that compression too. That all said, I've played a few clones where the high end doesn't roll off when you really push the amp and the tone stays stiff and bright. On some clones I could see how the 500pf position would not be welcome.

[Fischerman]

Yes you are right,But the jcm has a CF and the express is plate loaded in the pre amp section.I don't know about the concorde.

That's one of the few main differences...the Concorde has a CF at the end of the preamp...but the tone stack is still in the same Express/Komet spot.