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Marshall JCM-800 50 watt top; any good?

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11/30/1999 3:24 AM

Marshall JCM-800 50 watt top; any good?

I am considering getting a late 1980s JCM-800 50 watt master volume head. Want to use for chunky blues rhythm sound for blues at low to mid club levels. I know the master volumes usually kill your tone, especially the clarity and presence. I am less concerned about the lead tone since I use a tube screamer for solos. Planning to run this head thru my 4X10 marshall cabinet. Pls comment about the sound of these amps, as well as the reliability. I am pretty spoiled by my BF Fenders, which are pretty bulletproof! Tx!!

11/30/1999 4:42 PM
Lou	RB, I think it will sound fine if you fiddle around with the controls a bit. I use a JCM-800 50 watt master v with a Soundcity 4-10 bottom for Power Pop stuff and get a great chord tone's out of it. I kick in a rat for solo's. Good Luck Cheers Lou

11/30/1999 11:42 PM
jc	Good and Loud I had one of these. Played it through a 2X12. It definitely needed to be turned up to chunk. And that was far past low to mid level club volume . It did sound good though specially after clipped the input caps.

12/1/1999 6:03 AM

Re: Marshall JCM-800 50 watt top; any good?

I've had several JCM-800's and here's what I can tell you. The best JCM-800's are the 100 watt heads. They sound smoother and have a better sounding Master Volume than the 50 watt version. The 50 Watt Master Volume sounds like it clips too much. The 100 watt will outright crunch when cranked all the way. The 50 watt on the other hand will mush and will need to be cranked to '8' rather than '10' to sound good. Finally, the 50 watt head sounds dirtier than the smoother 100 watt head.

Another thing you should be aware of regarding JCM-800's is their output tube complement. All JCM-800's sold new in the US used 6550's rather EL-34's as original equipment. Those sold in Britain on the other hand used EL-34's. The amp was actually designed with EL-34's in mind but the cheap ass EL-34's of the 1980's didn't hold up well in shipping to the States. Alot of people over the years have converted the 6550's over to EL-34's by implementing a slight bias change. You may not want to do this.

The heavy metal notoriety that the JCM-800 made for itself was based on the 6550. It's a tube that just doesn't like to distort. When it finally is cranked to the point of being overdriven, it distorts with more balls than any other Marshall ever made. The same can not be said of the EL-34 version.

I have always preferred my JCM-800's to have 6550's. Not any old 6550 will do. The 6550's that came with th amp were of US manufacture General Electric Variety and these are what are recommended. Unfortunately they are quite rare and expensive nowadays so many people compromise and do the EL-34 conversion.

Finally, do not buy a JCM-800 that has chineese 6550's in it. You will be sorry. You won't get the sound that the amp is known for. Groove Tubes used to brand their chinese 6550's as 6550C's. Stay away from them. They sound very bright and tinny and woun't crunch.

BBP

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12/1/1999 5:40 PM
GCT	>>>Finally, do not buy a JCM-800 that has chineese 6550's in it. You will be sorry. You won't get the sound that the amp is known for. <<< Why, can't he just replace the chinese 6550's? Besides, you'd have to be real lucky to find a JCM800 head with GE6550's in good shape. ...and a nice set of Svets or Tesla EL34's might NOT do that much harm to a JCM800 anyway.

12/1/1999 11:44 PM

Psycho Bass Guy

I have also seen them with big bottled 6CA7's. Our band's rhythm guitar player uses one and it has always had fat 6CA7's in it. They're kind of like a cross between a regular EL34 and a 6550 anyway. It is the 100 watter and sounds downright awesome. (It crunches like peanut brittle candy!) If you want to use 6550's in one, any modern 6550 will sound good, excluding Chinese. I TORTURE Svetlana and Sovtek 6550's on a regular basis in my bass amps and can say that they hold up just as well, if not better, than old GE's.

Also, the thing with the old Tungsol 6550's is just hype. They just sound like a 'regular' 6550 with less output. That means they have a sooner, sweeter breakup, but neither they, nor the old GE's are worth what the hifi market has driven their prices to. Now, if you want SERIOUS crunch, try KT88's and turn it into a smaller Major.

Psycho (the very real one) >^}

12/2/1999 1:25 AM

I've just glommed onto 4 NOS Amperex 6550's, still in the original boxes with a thick layer of dust. I'm toying with the idea of using them in my Marshall clone. I'm running about 750v no load and 400v screens. I got a nice swinging choke from Fair Radio and could cut the B+ down to 550v or so - anybody familiar with Amperex and can give me some useful thoughts? I wasn't aware that Amperex actually made their own 6550 but if they're re-brands they're too old to have come from China...

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