whats the difference between the JCM 800 and 900?

[DragonSarc]

whats the difference between the JCM 800 and 900? what are the pros and cons/advantages and disadvanteges? I got the 900 4100 100watts its my first marshall tube amp i have a valvestate before, i know its a step up(big one too), im thinking of selling my 900 and get the 800 but before i do that i need info cuz i think i got a good deal on my 900. Thanks all

how about the JCM2000?

 

[PaoloJM]

whats the difference between the JCM 800 and 900? what are the pros and cons/advantages and disadvanteges? I got the 900 4100 100watts its my first marshall tube amp i have a valvestate before, i know its a step up(big one too), im thinking of selling my 900 and get the 800 but before i do that i need info cuz i think i got a good deal on my 900. Thanks all

how about the JCM2000?

Cons of the 800 2203 compared to the 900 4100

1. It's a single channel amp
2. No reverb or effects loop (the 2205/2210 has dual channel switching, reverb and effects loop)
3. No power switching, could be fitted if really wanted
4. No line out, but one could be fitted if you really wanted
5. No valve failure LEDs, kinda nice to have but I can usually tell when mine have failed as the amp doesn't work!!
6. Less gain on tap

Pro's of the 800 series

1. Less crap in the signal patch, transitors, op-amps and such-like
2. Eat's boost pedals for break-fast
3. Old school power section with a proper choke for B+
4. Easily modded for more gain
5. It just f**kin' sounds better!!

This is just a short-list of the major differences as I see them, there are many, many other minor differences.
Hope the last point didn't get too technical.

The 900 seems to have been designed to encapsulate all the mods that people were doing with the 800 series in one all signing, all dancing amp. They didn't do a bad job at all and it is a fine amp. I can't help thinking, though, that it's a bit over engineered and lost some of it's focus along the way.
The 2,000 I haven't used nor do I know much about it to comment.

 

[Brett Blackmore]

The JCM 800 was the result of taking a plexi and adding a more advanced valve based pre-amp (more advanced than the earlier Master vol models) which gave you the advantage of having an all-tube distortion plus the extra distortion from a master volume type preamp. The drawback was the fact that it needed to be played loud to get both the main-and preamp tube distortion. If you could not crank it up then you needed to add more gain thru a pedal or preamp. The advantage is that it has a beautiful creamy-distorted sound when cranked up and there is a lot of push and bottom end - afterall the motor inside it is a Plexi... eg. M.Schenker only uses 50w Marshall JCM 800's.

The JCM 900 was supposed to be the new JCM800 but with more gain and a wonderfull pearly clean channel. Yet they made 2 mistakes. One was to use transistors on the B channel to get more gain out of the preamp stage. Somehow the natural response (I feel) was throttled and the tube compression is lighter. The transistors do not make it sing and secondly, they did not make enough gain - the JCM 900 is NOT high gain, but a medium gain. They corrected this later with the ensuing SLX model by adding one more valve. (ps. I am saying transistors but they might be diodes etc.. I am not a technician). Anyway, thru more luck than planning this amp was coincidently launched as the new emerging grunge wave arrived. It became a non-shredding favourite, especially amongst rhythem guitarists or punk bands. (it was the highest selling model until the JCM2000 arrived). I know I have critized its transistor staged gain design, but at the end of the day this amp truly sounds great - is has that true Kerrang!! Marshall sound and do not forget it has a wonderfull clean channel which can crunch very close to the older non-MV Plexis. I can play AC/DC or Hendrix on this til' the cows come home. Probably the A channel is NOT affected by the transistor gain and it is the original JCM 800 channel. I guess there are users who crank this channel and add a o/d pedal and find that sweet spot... Nirvana..

The DSL & TSL amps after the JCM 900 had no more transistors in the preamp stage, they went back to the JCM800 design and used additional preamp tubes instead.

Cheers Brett

 

[5er driver]

The JCM 900 was supposed to be the new JCM800 but with more gain and a wonderfull pearly clean channel. Yet they made 2 mistakes. One was to use transistors on the B channel to get more gain out of the preamp stage. Somehow the natural response (I feel) was throttled and the tube compression is lighter. The transistors do not make it sing and secondly, they did not make enough gain - the JCM 900 is NOT high gain, but a medium gain. They corrected this later with the ensuing SLX model by adding one more valve. (ps. I am saying transistors but they might be diodes etc.. I am not a technician).

Brett, I think the transisitors you are referring to are actually are clipping diodes. The SL-X doesn't use them for distortion as it has the 4th preamp tube for that (super high gain). I may be wrong but I think there are no diodes at all in the SL-X except possibly in the effects loop for other reasons than distortion........

 

[DragonSarc]

so should i just stick with my 900 as to getting an 800? is there a big difference? i could still get the 800 sound on my 900? ( i play hendrix clapton ac/dc black sabath metallica slayer )

 

[stock_hippie]

Cons of the 800 2203 compared to the 900 4100

1. It's a single channel amp
2. No reverb or effects loop (the 2205/2210 has dual channel switching, reverb and effects loop)
3. No power switching, could be fitted if really wanted
4. No line out, but one could be fitted if you really wanted
5. No valve failure LEDs, kinda nice to have but I can usually tell when mine have failed as the amp doesn't work!!
6. Less gain on tap

Pro's of the 800 series

1. Less crap in the signal patch, transitors, op-amps and such-like
2. Eat's boost pedals for break-fast
3. Old school power section with a proper choke for B+
4. Easily modded for more gain
5. It just f**kin' sounds better!!

This is just a short-list of the major differences as I see them, there are many, many other minor differences.
Hope the last point didn't get too technical.

The 900 seems to have been designed to encapsulate all the mods that people were doing with the 800 series in one all signing, all dancing amp. They didn't do a bad job at all and it is a fine amp. I can't help thinking, though, that it's a bit over engineered and lost some of it's focus along the way.
The 2,000 I haven't used nor do I know much about it to comment.

Paolo...if you have a moment could you give me your thoughts on the AVT 50H?...i do outdoor gigs and tend more toward country western southern rock..not too much hendrix..id use a marshall 4x12 cab...ATV 50 is pretty cheap for me at $350...i always liked the idea of the external marshall cabs....thanks!

 

[PaoloJM]

Paolo...if you have a moment could you give me your thoughts on the AVT 50H?...i do outdoor gigs and tend more toward country western southern rock..not too much hendrix..id use a marshall 4x12 cab...ATV 50 is pretty cheap for me at $350...i always liked the idea of the external marshall cabs....thanks!

Sorry Hippie dude, I'm more of an old school Marshall stack kinda guy. I'm just not familiar with with the ATV amps at all.

 

[aussiebluesville]

this site may help
Marshall Amps Info & Schematics

 

[Brett Blackmore]

Hi 5er Driver,

yes, clipping diodes - I thought 'transistor' was not right.

Thx. Brett

 

[steelhorse]

I added an MXR 10 band EQ (not the KK model) swapped the tubes for a high gain set of E34L's and preamp tubes from Euro and this thing beats serious ass I kid you not. I run the EQ thru the FX loop and I don't need no steekeeng OD pedals.

A few of the members here recommended an EQ and my Boss wasn't cutting it and after the many hours reading reviews on the MXR I went for it.

Granted I don't have the 4100 with the built in reverb but I have a verbzilla that is an animal. I also use a DD7 and a smartgate at the end of the board and I'm very pleased.

BTW I have the JCM 900 SLX-200/1960A cab which I got in trade for a combo amp.

Go figure.

 

[Mats A]

The JCM 800 was the result of taking a plexi and adding a more advanced valve based pre-amp (more advanced than the earlier Master vol models) which gave you the advantage of having an all-tube distortion plus the extra distortion from a master volume type preamp. The drawback was the fact that it needed to be played loud to get both the main-and preamp tube distortion. If you could not crank it up then you needed to add more gain thru a pedal or preamp. The advantage is that it has a beautiful creamy-distorted sound when cranked up and there is a lot of push and bottom end - afterall the motor inside it is a Plexi... eg. M.Schenker only uses 50w Marshall JCM 800's.

The JCM 900 was supposed to be the new JCM800 but with more gain and a wonderfull pearly clean channel. Yet they made 2 mistakes. One was to use transistors on the B channel to get more gain out of the preamp stage. Somehow the natural response (I feel) was throttled and the tube compression is lighter. The transistors do not make it sing and secondly, they did not make enough gain - the JCM 900 is NOT high gain, but a medium gain. They corrected this later with the ensuing SLX model by adding one more valve. (ps. I am saying transistors but they might be diodes etc.. I am not a technician). Anyway, thru more luck than planning this amp was coincidently launched as the new emerging grunge wave arrived. It became a non-shredding favourite, especially amongst rhythem guitarists or punk bands. (it was the highest selling model until the JCM2000 arrived). I know I have critized its transistor staged gain design, but at the end of the day this amp truly sounds great - is has that true Kerrang!! Marshall sound and do not forget it has a wonderfull clean channel which can crunch very close to the older non-MV Plexis. I can play AC/DC or Hendrix on this til' the cows come home. Probably the A channel is NOT affected by the transistor gain and it is the original JCM 800 channel. I guess there are users who crank this channel and add a o/d pedal and find that sweet spot... Nirvana..

The DSL & TSL amps after the JCM 900 had no more transistors in the preamp stage, they went back to the JCM800 design and used additional preamp tubes instead.

Cheers Brett

Actually Schenker uses the JCM 800 Split Channel amp wich has diodes clipping in it. And cit must not be a bad thing. It can actually sound good. If you use an overdrive or distortion device it also has diodes or transistors clipping.

 

[5er driver]

BTW I have the JCM 900 SLX-200/1960A cab......
Go figure.

There's an SL-X 200? What does it have for power tubes and how many? I am only aware of the 2100 and 2500 models.

 

[Mats A]

Never heard of that one. Are you sure It was a SL-X 200

 

[5er driver]

I think it's a typo, I think he meant SL-X 2100.

I've got one myself, what a monster!

 

[BYoung]

Mornin' All,
Does anybody have any info on the 250 watt Series 2000 head? I'm not talking about the DSL. I came across a reference while looking for tubes for my Major and I don't really remember this amp.

 

[steelhorse]

It was a typo, sorry, I meant SLX-2100

 

[mxr2000]

Actually Schenker uses the JCM 800 Split Channel amp wich has diodes clipping in it. And cit must not be a bad thing. It can actually sound good. If you use an overdrive or distortion device it also has diodes or transistors clipping.

Sorry my friend but Schenker uses the early 80's 2205 design without the diode clips..

 

[Mats A]

Sorry my friend but Schenker uses the early 80's 2205 design without the diode clips..

Sorry my friend! But there are two versions of the 2205/2210. The the first was only sold in the USA and was only made for a very short time, and both had diodes clipping in there signal chain. I got schematics for both of them.

 

[HOT TUBES 70]

One more thing about the jcm 800 series ,the early 800s came out with 6550 output
tubes, I have played a zakk wylde head and this is his tube of choice for his 800s.
a very muscular sounding amp i might add. i just thought i would add this to the mix on
the subject of 800/900 difference .