NGD!: Marshall JCM 900 DR4500

allbutromeo

Well-known member
Bought a JCM 900 4500 50w Dual Reverb, its on the truck to be delivered today. Any fellow 900 owners have any advice? I know 900s aren't the most popular amps, especially the Dual Reverbs, but I don't need all of the "sell it and buy an 800" comments. 800s are great amps, but if that's what I wanted then that's what I would have bought.
 
Re: NGD!: Marshall JCM 900 DR4500

I know, I know, pics or it didn't happen. I'll have some as soon as I get home from work.
 
Re: NGD!: Marshall JCM 900 DR4500

Sell it and buy a Plexi?


;)


I hated my DR, BITD, but I was running T75s at the time. They sound much better with G12M or G12H speakers.
 
Re: NGD!: Marshall JCM 900 DR4500

I've never tried a 900 but Lars from rancid gets good tones from his (dunno which version).

Nonetheless, every new amp day deserves a "congrats and enjoy" so here it is: Congrats and Enjoy!
 
Re: NGD!: Marshall JCM 900 DR4500

I liked my combo I used for many years. I ran a tube king into it though, which greatly colored the sound. But I did the same with the 800 head I used after that.
 
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Re: NGD!: Marshall JCM 900 DR4500

five years ago I had a Marshall JCM 900 50 watter, not the el34 version

I dig giant sludge music and was running it through my Orange 212 closed back cab and it sounded horrible. way too much treble and the knobs did not work for bassy downtuned sludge music it seemed, it really probably needed a different cab anyways. sold it for my Orange Thunderverb 50 and am very happy now with my amp situation.
 
Re: NGD!: Marshall JCM 900 DR4500

A friend of mine used a 4500 for years and he had the best rock tones I've ever heard live. They really don't sound good until you crank them, then they sound fantastic.
 
Re: NGD!: Marshall JCM 900 DR4500

A friend of mine used a 4500 for years and he had the best rock tones I've ever heard live. They really don't sound good until you crank them, then they sound fantastic.
Ive heard that, I haven't played one in probably 10 years but I always liked them, though they were usually 100w. I mostly play late 90's early 2000's punk and post-hardcore and seem to remember a lot of bands I like having at least one guy using these.
 
Re: NGD!: Marshall JCM 900 DR4500

Also someone posted a shootout here recently where the 900 sounded great - as good as the 800 if not even more appropriate for the riff (I think it was scorpions rock you like a hurricane)
 
Re: NGD!: Marshall JCM 900 DR4500

So desperate to get home and jam on it all day... Turns out that all of my speaker cables are at my rehearsal space and/or the studio we're recording at.
 
Re: NGD!: Marshall JCM 900 DR4500

Hay every body, come over and check this out! It really did happen, he has pics!!! LOL.
Congrats dude! Now MAKE SOME NOISE!!!
 
Re: NGD!: Marshall JCM 900 DR4500

The JCM 900 SL-X was my main amp for years. I ran it through the 900 Marshall cab. The one thing I will say is that, it give you one sound, and one sound only. If you like it, then it's your amp. If not, you'll hate it. There's really no in-between.

Weezer's Buddy Holly was recorded with my same set-up. If you listen to that song, then you will get the idea of what (specifically the SL-X) can do.
 
Re: NGD!: Marshall JCM 900 DR4500

IMHO, they can be quite good amps with a few mods. Just Google "JCM900 4500 mods", there's plenty of reference material out there.
 
Re: NGD!: Marshall JCM 900 DR4500

Step one will be new tubes, then probably take out the preset tone/voicing circuit on channel b and maybe take the diodes out
 
Re: NGD!: Marshall JCM 900 DR4500

that one looks just like mine, I had the dual reverb jcm 900 50 watt non-el34 version

having the right cab and playing the right tunes go far with that head. I sold it back to guitar center, and the dude that checked it out at GC plugged it in and boy did it sound brilliant with his style of playing and that cab! He was like, this thing is perfect, why are you selling it?
 
Re: NGD!: Marshall JCM 900 DR4500

Step one will be new tubes, then probably take out the preset tone/voicing circuit on channel b and maybe take the diodes out

I have a JCM900 4100 that I bought brand new in 1992 when I was 15 years old.

Years ago I talked to both Trace at Voodoo amps and Jerry at FJA mods at great length about modifying my 4100, neither was excited to do it. Both said the work needed to remove the diodes is way too much it also creates reliability issues. The implementation of the preamp is very different from the JCM900 2100/2500 amps which it isnt very difficult to remove the diodes from. Basically in the 4100 and 4500's the preamp is a set of op amps all the gain stages are solid state v1 is your cathode follower v2 is the tone network and v3 is the reverb driver.

Trace at the end said he would do it but its basically gutting the preamp and rebuilding, Jerry wasnt so hot on the idea said a better route would be either to just upgrade the power tranny otherwise leave it alone. At this point ive read neither of these guys will perform mods on 900's

Consider how cheap and easy you can find better sounding marshalls i.e DSL's JVM's Vintage moderns... This is one of those amps get it up to snuff ( it may need caps as old as it is) and otherwise just leave it alone. If you hate the tone sell it.

I know of a bunch of guys who have gone into them and started clipping diodes and jumpering stuff in attempts to try and cure the excess treble. Its much easier and more predictable to swap speakers and add an eq pedal to your loop than to do that crap.
 
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