Marshall JCM 800 Combo

wntbtw

wntbtw

New member
Hi--I`m intersted in the Marshall JCM 800 Combo amp and am wondering if anyone could give me their opinion, thoughts, etc. on these particular amps. I know there were 6 models available and I`m paricularly interested in the 4210 model as i like reverb, but would like to know how they sound in general along w/ reliability, etc. Any help will be greatly appreciated! Thank you.
 
Re: Marshall JCM 800 Combo

My freind has one of the early models from the '80's, that we trade back and forth between us. Sounds really nice. Good creamy distortion. It's been described as a "one trick pony", but I like it. Can't speak about the models with reverb. Never tried one. Robert S is real knowledgable about the JCM800 series. You might ask him or wait and see if he replys to the thread.

Good luck,

Jeff
 
Re: Marshall JCM 800 Combo

some of the best guitar sounds i ever heard were produced by the jcm 800. i played on a couple with my invader fitted strat and it sounded TERRIBLE. no matter what i did, i couldn't get the right tone. it was all treble and hi mids. then a guy with an LP plugged in and it sounded awesome. just be sure to try with your own guitars and crank it up. if you like it, then buy it, no second thoughts. if you don't, there is no way to fix the sound by turning the knobs or anything, just look for another amp.
 
Re: Marshall JCM 800 Combo

The 4210 is the 50 watt version- channel switching, effects loop, reverb. I have the 100 watt combo version.

I love mine, but it is a one trick pony. Don't get it if you want a clean channel, the clean channel is dull and boring. Maybe if you put a chorus or delay in the effects loop it may help.

The overdrive more than makes up for it. The amp loves pedals. I suggest a modded TS-9, TS-9DX, or in my opinion, MXR Zakk Wylde overdrive. It'll give you killer gain, but also noise compared to today's amps.

Very LOUD amps.

If you buy one, immediately swap in some new tubes and have it rebiased, but get an estimate first- I got ripped off. The difference with new tubes is like night and day, depending how long the current ones were sitting in there.

Reliability? Mine's a 1989, tolex worn off, and just needed new tubes. I'd say 18 years for an amp is pretty impressive, though I bought a Carvin V3 as a second more versatile amp. It doesn't have the same mojo as the Marshall, though has a vibe all its own.
 
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Re: Marshall JCM 800 Combo

I've owned four. One channel switching 100 watt head and three 50 watt combo amps: two vertical input and one side by side input.

My favorite is the '82 vertical input version with the high and low inputs. The tone is livlier, fuller and better than the side by side input '86 model I owned.

My current JCM-800 is an '82 vertical input Model 4010 50 watt model with a single 12" speaker that I bought from James Hoffman. It was his personal amp and it's just wonderful.

The original speaker was a G12M-70 and Jim changed it to a G12M-65. Much better! More bass and a fuller tone and tons of crunchy texture compared to the smoother and less crunchy tone of the G12M-70.

Mine still has the original 6550 output tubes. Sounds killer, although I changed the 6550's to EL34's in all of my other JCM-800's

I may or may not change the 6550's to EL-34's in this one. It's very stock and sounds great as is.

Tons of that growly, barky, "bagful of angry bumble bees" tone I make fun of so often here! LOL! I was just wailing through it this morning with my single bridge HB Strat with a Duncan Custom Shop EVH/78.

What a blast!

I have not been able to compare this amp to my 50 watt Matchless Chieftan yet. It's also a one 12" amp.

After getting the Chieftan I sold all three of my Marshalls.

I had a handwired '70 50 watt head and two JCM800 50 watt two 12 combos.

But I missed that authentic Msrshall tone.

There's nothing like a real good Marshall, and this one roars like a Harley Davidson motorcycle that's just barely street legal! lol! Although with just a single 12 the volume is much more manageable than my other amps which were two x 12 versions of the same 50 watt chassis.

In terms of what to look for in a JCM 800 combo amp, I'd look for:

50 watts
vertical High and Low inputs, and personally, I'd avoid the channel switching model
metal chassis straps on top...NOT PLASTIC chassis straps!

Lew
 
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Re: Marshall JCM 800 Combo

Lewguitar said:
I've owned four. One channel switching 100 watt head and three 50 watt combo amps: two vertical input and one side by side input.

My favorite is the '82 vertical input version with the high and low inputs. The tone is livlier, fuller and better than the side by side input '86 model I owned.



Lew
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The combo my friend has has the vertical inputs (High Low). I had it changed over to EL34's while I had it. Sounds killer, but one of the speakers needs to be reconed.

Jeff
 
Re: Marshall JCM 800 Combo

Nobody's said this, but some of these amps came with 6550s and most with EL34s. Definitely get the EL34s.

I had a a 4010--single channel, 50 watt, no reverb. Good amp, loud,...and yes, a one trick pony.

Much happier with my Mesas.

Bill
 
Re: Marshall JCM 800 Combo

Boogie Bill said:
Nobody's said this, but some of these amps came with 6550s and most with EL34s. Definitely get the EL34s.

I had a a 4010--single channel, 50 watt, no reverb. Good amp, loud,...and yes, a one trick pony.

Much happier with my Mesas.

Bill
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It's a one trick pony all right...but it's a trick no other amp can perform except another great Marshall.

It's just such a classic tone.

I suppose one could say Babe Ruth was a one trick pony too: all he did was hit home run after home run! lol!

There's nothing that nails the tone of a really good Marshall...except another really good Marshall.

Lew
 
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Re: Marshall JCM 800 Combo

Hi--thanks to everyone for their input! It`s been great to read what everyone has to say. So thank you all!

Lew--i have a question: why don`t you recommend the channel-switching model [4210]? I don`t know too much about these different models, but i do like having reverb. Any suggestions concerning that? I really don`t want the 2x12" speaker combo and so that leaves me with single channel 4010 model that does not have reverb, which i`d really like to have! Thanks.
 
Re: Marshall JCM 800 Combo

wntbtw said:
Hi--thanks to everyone for their input! It`s been great to read what everyone has to say. So thank you all!

Lew--i have a question: why don`t you recommend the channel-switching model [4210]? I don`t know too much about these different models, but i do like having reverb. Any suggestions concerning that? I really don`t want the 2x12" speaker combo and so that leaves me with single channel 4010 model that does not have reverb, which i`d really like to have! Thanks.
Click to expand...

Personally, I don't think the clean and semi-clean sounds in the channel switching model are as 3-D, as open and as lively or as deep as the clean/semi-clean sounds in the regular '82 version without channel switching.

And the reverb is transistor driven and not what I like: I like Fender blackface or silverface style tube driven spring reverb...I like the sound of that circuit.

The distortion is more over the top in the channel switching model and it's a good amp and everything, but when it comes to the kind of tones I like, amps with simpler and less complicated signal paths seems to sound more natural and just plain better to me.

SRV used a vertical input non-channel switching JCM 800 in his regular amp line up pretty much everytime he recorded pr performed, by the way. He knew.

Lew

PS: here's my Marshall 4010 50 watt, BTW:
 
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Re: Marshall JCM 800 Combo

I've had both the channel switching, and the non-channel switching versions in the past. I concur that in most cases, the single channel switching ones are to be prefered-unless your way into 80's metal.

The channel switching models do that 80's metal thing very well.

With the channel switching/reverb models, the 6550 tubes may work better than the EL34, for cleans, as the distortion is pre-amp, anyway. With almost all Marshalls, the clean will be a bit dull at low volume levels.

The single channel versions do give a better "clean" with the guitar volume backed off a bit.
 
Re: Marshall JCM 800 Combo

Lewguitar said:
In terms of what to look for in a JCM 800 combo amp, I'd look for:

50 watts
vertical High and Low inputs, and personally, I'd avoid the channel switching model
metal chassis straps on top...NOT PLASTIC chassis straps!

Lew
Click to expand...

By chassis strap are you referring to the end caps on the amp handle? Marshall only used the gold metal ones in late '81 and early '82 prior to switching to black plastic caps in mid-'82. In fact the only circuit differences between early (vertical) and late (horizontal) 50 watters is the use of PCB-mounted components on the latter.

Tone changes from year to year can largely be attributed to the change to G12-M70 speakers in '83, EL-34 tubes in '85, and G12-T75 speakers in '86. These changes in output tubes and speakers are the primary reason 50W JCM800s from different years sound differently. Another reason is the rather loose component tolerances used at the time.

Of course this applies to 50W JCM800s only. The 100W amps are an entirely different and more complicated group that I'd be glad to detail if anyone's interested.

My personal favorite JCM800 combination is 6550 output tubes into G12-65 speakers.
 
Re: Marshall JCM 800 Combo

dystrust said:
By chassis strap are you referring to the end caps on the amp handle? Marshall only used the gold metal ones in late '81 and early '82 prior to switching to black plastic caps in mid-'82. In fact the only circuit differences between early (vertical) and late (horizontal) 50 watters is the use of PCB-mounted components on the latter.

Tone changes from year to year can largely be attributed to the change to G12-M70 speakers in '83, EL-34 tubes in '85, and G12-T75 speakers in '86. These changes in output tubes and speakers are the primary reason 50W JCM800s from different years sound differently. Another reason is the rather loose component tolerances used at the time.

Of course this applies to 50W JCM800s only. The 100W amps are an entirely different and more complicated group that I'd be glad to detail if anyone's interested.

My personal favorite JCM800 combination is 6550 output tubes into G12-65 speakers.
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Just like in a Fender Twin Reverb, there are four screws in the top of the cabinet that the chassis hangs from. And instead of four washers, Fender used two metal chassis straps...and so do the '82 Marshall JCM 800's like mine. My '86 used plastic chassis straps.

Regarding the circuits in a '82 with vertical inputs and a '86 with side by side inputs: they are not identical. People think they are but they are not. There's a choke in one (the '82 I think) that is not in the other and the voltages are higher in the '86 compared to the '82.

Higher voltages on the preamp tubes can give an amp a brighter, edgier, thinner tone...and in the '86 model it does just that.

No kidding. I've compared them side by side and worked my buns off experimenting and trying to tweak the '86 into sounding as good as the '82. Lowering the voltages on the preamp tubes by increasing the size of the voltage dropping resistors helped...but that raised the voltage on the output tubes.

Bottom line is they are not quite the same exact circuit...and the pots are mounted directly to the circuit board in the '86 instead of by flying leads as it is in the '82...as you mentioned.

Lew
 
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Re: Marshall JCM 800 Combo

Lewguitar said:
Just like in a Fender Twin Reverb, there are four screws in the top of the cabinet that the chassis hangs from. And instead of four washers, Fender used two metal chassis straps...and so do the '82 Marshall JCM 800's like mine. My '86 used plastic chassis straps.

Regarding the circuits in a '82 with vertical inputs and a '86 with side by side inputs: they are not identical. People think they are but they are not. There's a choke in one (the '82 I think) that is not in the other and the voltages are higher in the '86 compared to the '82.

Higher voltages on the preamp tubes can give an amp a brighter, edgier, thinner tone...and in the '86 model it does just that.

No kidding. I've compared them side by side and worked my buns off experimenting and trying to tweak the '86 into sounding as good as the '82. Lowering the voltages on the preamp tubes by increasing the size of the voltage dropping resistors helped...but that raised the voltage on the output tubes.

Bottom line is they are not quite the same exact circuit...and the pots are mounted directly to the circuit board in the '86 instead of by flying leads as it is in the '82...as you mentioned.

Lew
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Thanks for the info Lew. I know our tastes aren't the same and I appreciate learning something new about an old favorite amp. I don't own a JCM800 at the moment but since I'll soon be starting a higher paying job, it may be in the cards. I prefer heads to combos, and given this information I'll be looking for a pre '85 2203 or 2204 with 6550s.

Thanks again!
:headbang:
 
Re: Marshall JCM 800 Combo

dystrust said:
Thanks for the info Lew. I know our tastes aren't the same and I appreciate learning something new about an old favorite amp. I don't own a JCM800 at the moment but since I'll soon be starting a higher paying job, it may be in the cards. I prefer heads to combos, and given this information I'll be looking for a pre '85 2203 or 2204 with 6550s.

Thanks again!
:headbang:
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You're welcome! The models exported to the USA did indeed come with 6550 tubes...but the models made for the UK came with the classic Marshall output tube: EL-34. Most players prefer EL-34's and it's a simple fix to convert the amp to EL-34's. I think it's just a matter of replacing one resisitor in the bias supply.

Lew
 
Re: Marshall JCM 800 Combo

Lewguitar said:
You're welcome! The models exported to the USA did indeed come with 6550 tubes...but the models made for the UK came with the classic Marshall output tube: EL-34. Most players prefer EL-34's and it's a simple fix to convert the amp to EL-34's. I think it's just a matter of replacing one resistor in the bias supply.
Lew
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I'm not sure about this, but it seems Marshall changed the 2203/2204 tone stack between the JMP & JCM800 versions. In general I prefer EL-34s at least in my Jubilee and in JMPs. However I think 800s sound a bit bright and thin with 34s. 6550s resolve both of these issues. On the other hand, JMP 2203s and 2204s sound dull and lifeless with 6550s. Kinda like you have dead strings all the time...

I may be full of it here, but I've noticed this trend with several JMPs and early 800s. Never played a horizonal 800 I liked, so I'm not as familiar with those.
 
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