ProCo Rat ? Juicing a JCM800?
- Thread starter BloodRose
- Start date
J Moose
New member
Re: ProCo Rat ? Juicing a JCM800?
Sorry to hear you aren't diggin' the 800 so much...
When that amp was in my possession I, nor anyone else who plugged into it thought it was "lacking" gain... but I always ran it with the master opened up to some degree. Gain on "10" and masters on at least 3-4 if not higher... and it was always crushing.
Never thought it needed more then a tube screamer on top for solo boosts...
I had a mid 80s small box RAT for a while (bought on the advice of the FireGuy) and honestly never dug that box very much. However! It did sound really cool pushing the 800 when the gain was backed down to about 6 or 7... RAT pushing it w/ everything around midway give or take.
Was instant Anthrax "State of Euphoria" tone...
I'm a bit lost if you say you need 'more' gain then that 800 can deliver...
There's nothing special about Zakks amps in the Ozzy years... basically well 800's turned way the fukk up and pushed with a boss SD1 for solos.\
As its said...
Tone is in the hands.
And the ability to dial in the amp...
Sorry to hear you aren't diggin' the 800 so much...
When that amp was in my possession I, nor anyone else who plugged into it thought it was "lacking" gain... but I always ran it with the master opened up to some degree. Gain on "10" and masters on at least 3-4 if not higher... and it was always crushing.
Never thought it needed more then a tube screamer on top for solo boosts...
I had a mid 80s small box RAT for a while (bought on the advice of the FireGuy) and honestly never dug that box very much. However! It did sound really cool pushing the 800 when the gain was backed down to about 6 or 7... RAT pushing it w/ everything around midway give or take.
Was instant Anthrax "State of Euphoria" tone...
I'm a bit lost if you say you need 'more' gain then that 800 can deliver...
There's nothing special about Zakks amps in the Ozzy years... basically well 800's turned way the fukk up and pushed with a boss SD1 for solos.\
As its said...
Tone is in the hands.
And the ability to dial in the amp...
Christopher Caruana
New member
Re: ProCo Rat ? Juicing a JCM800?
+1. Take the old EVH rule........turn the volume to 10. The 800's (and any Marshall) need to be pushed to get any good sound out of them. Dont buy any pedals until you have had the volume on about 6 or 7
Re: ProCo Rat ? Juicing a JCM800?
Dont get me wrong Bro, I LOVE the amp! Its my #1.
And, Im sure I get more juice with this one than I would a stocker. I just sounds to me like the gain isnt as much as some of 80s recordings that I love so much. Im sure the biggest thing is the fact I cant crank it to 10. And, perhaps, since Im only running 1 4x12, it doesnt sound as "big".
It isnt so much that Im Lacking gain, as Im looking for that honk type sound.. This one sounds deeper and "woolly". (make sense??)
Dont get me wrong Bro, I LOVE the amp! Its my #1.
And, Im sure I get more juice with this one than I would a stocker. I just sounds to me like the gain isnt as much as some of 80s recordings that I love so much. Im sure the biggest thing is the fact I cant crank it to 10. And, perhaps, since Im only running 1 4x12, it doesnt sound as "big".
It isnt so much that Im Lacking gain, as Im looking for that honk type sound.. This one sounds deeper and "woolly". (make sense??)
J Moose
New member
Re: ProCo Rat ? Juicing a JCM800?
You can't really compare what you get in the room, raw off the amp to recordings... ESPECIALLY those highly processed & overdubbed '80s recordings which are generally a wall of chorused & delayed guitars.
Maybe invest in a rack system to go with the amp...
But anyway... as a starting point...
Turn the preamp gain to 10 (8 -10 is where it comes alive, below that is pretty mellow, JTM45 range)... and set the EQ's to noon all the way across. Presence to taste... I generally liked it lower... maybe 3 or 4 but it depends on how loud the amp is & where the treble is at...
Personal preference as well.
Channel volume up around 4 or 5, and master to about 3 or 4. Anything lower and its not really going to breathe. And higher is better. There's a balance there that you'll figure out. You could try pulling that one preamp tube as well...
And then tweak it all from there.
You've mentioned several times that you can't really crank it and your not gigging... so maybe ditch the 4x12 for a good 1x12 which will let you push the power tubes without pushing as much physical air.
Maybe also get a Hot Plate or other attenuator if the smaller cab doesn't entirely bring it to a manageable level.
FWIW - for those following along at home... I used to own his 800, which is a 2205 that was modified into a Jubilee of sorts. So, its not really a "stock" 800. There's quite a bit more on tap there... and yes, more bottom end!!!
You can't really compare what you get in the room, raw off the amp to recordings... ESPECIALLY those highly processed & overdubbed '80s recordings which are generally a wall of chorused & delayed guitars.
Maybe invest in a rack system to go with the amp...
But anyway... as a starting point...
Turn the preamp gain to 10 (8 -10 is where it comes alive, below that is pretty mellow, JTM45 range)... and set the EQ's to noon all the way across. Presence to taste... I generally liked it lower... maybe 3 or 4 but it depends on how loud the amp is & where the treble is at...
Personal preference as well.
Channel volume up around 4 or 5, and master to about 3 or 4. Anything lower and its not really going to breathe. And higher is better. There's a balance there that you'll figure out. You could try pulling that one preamp tube as well...
And then tweak it all from there.
You've mentioned several times that you can't really crank it and your not gigging... so maybe ditch the 4x12 for a good 1x12 which will let you push the power tubes without pushing as much physical air.
Maybe also get a Hot Plate or other attenuator if the smaller cab doesn't entirely bring it to a manageable level.
FWIW - for those following along at home... I used to own his 800, which is a 2205 that was modified into a Jubilee of sorts. So, its not really a "stock" 800. There's quite a bit more on tap there... and yes, more bottom end!!!
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Invader09
New member
Re: ProCo Rat ? Juicing a JCM800?
I have a mid 80's JCM 800 2204 (50 watt model) and with high output duncans in my guitars + pre-amp on 10 it's perfect ! I do own a RAT and sometimes will leave it on for a extra boost (depending on the day) when I do, I set it at ~~~ Gain=2, filter=5, volume =10. Perfect boost. But I turn my amp up for recording quite often and the master volume is usually at 8, so you know i'm pushing the **** out of it. When you get it up high like that, the tone is unbelievable !
I have a mid 80's JCM 800 2204 (50 watt model) and with high output duncans in my guitars + pre-amp on 10 it's perfect ! I do own a RAT and sometimes will leave it on for a extra boost (depending on the day) when I do, I set it at ~~~ Gain=2, filter=5, volume =10. Perfect boost. But I turn my amp up for recording quite often and the master volume is usually at 8, so you know i'm pushing the **** out of it. When you get it up high like that, the tone is unbelievable !
Re: ProCo Rat ? Juicing a JCM800?
Thanks Bro! Yeah, she is def a keeper! I just wanna get the most out of it.
Im looking into a 2x12 cab and a hot plate
Thanks Bro! Yeah, she is def a keeper! I just wanna get the most out of it.
Im looking into a 2x12 cab and a hot plate
STRATDELUXER97
Stratoblaster Tone Meister
Re: ProCo Rat ? Juicing a JCM800?
6550's or EL34s in your amp Bloodrose? You never answered..
6550's or EL34s in your amp Bloodrose? You never answered..
Re: ProCo Rat ? Juicing a JCM800?
Im sorry Bro! I been hoping to get it out of storage to play it and to check for you cuz I cant remember. I think its el34s, but something tells me that its 6550s cuz I remember being suprised. Hopefully Ill have it tommorrow
Im sorry Bro! I been hoping to get it out of storage to play it and to check for you cuz I cant remember. I think its el34s, but something tells me that its 6550s cuz I remember being suprised. Hopefully Ill have it tommorrow
Invader09
New member
Re: ProCo Rat ? Juicing a JCM800?
Bloodrose, EL34's are best fit in the JCM800, hopefully thats what you have, 6550's just dont sound "marshall". If you do have 6550's in yoursz, you could just have the mod done to put EL34's in.. Goodluck, i'm interested in hearing which one yours has too.
Bloodrose, EL34's are best fit in the JCM800, hopefully thats what you have, 6550's just dont sound "marshall". If you do have 6550's in yoursz, you could just have the mod done to put EL34's in.. Goodluck, i'm interested in hearing which one yours has too.
Christopher Caruana
New member
Re: ProCo Rat ? Juicing a JCM800?
That might be the problem. Before you buy any pedals, Get some EL34's. They will break up a lot earlier and easier when pushed.
That might be the problem. Before you buy any pedals, Get some EL34's. They will break up a lot earlier and easier when pushed.
Invader09
New member
Re: ProCo Rat ? Juicing a JCM800?
YES ! get a mod done for EL34's ! It will sound SO much better ! and if you can, there kind of expensive, but get a nice matched set of old RFT EL34's ! There actually pretty cheap compared to most vintage power tubes, and are absolutly amazing sounding, plujs they last 3-4 times what current production power tubes last.... I have 2 mid 80's RFT's EL34's + 3 Sovtek LPS 12ax7's in mine. I perfer current production pre-amp tubes. But as Christopher said above, EL34's will give that classic Marshall break-up !
YES ! get a mod done for EL34's ! It will sound SO much better ! and if you can, there kind of expensive, but get a nice matched set of old RFT EL34's ! There actually pretty cheap compared to most vintage power tubes, and are absolutly amazing sounding, plujs they last 3-4 times what current production power tubes last.... I have 2 mid 80's RFT's EL34's + 3 Sovtek LPS 12ax7's in mine. I perfer current production pre-amp tubes. But as Christopher said above, EL34's will give that classic Marshall break-up !
Re: ProCo Rat ? Juicing a JCM800?
Wonder how much it'll cost to get it to run el34s??
I must say this:
First, I did blast it for awhile today and Yeah, sounds huge when LOUD! Matter of fact, one of my daughters came home from school and said she hear me nearly 2 blocks away! Hee hee hee :naughty:
Second, I played with the EQ and got a beautiful sound out of it. I dialed the mids up to about 8 and I tried dialing the bass up.. Ive NEVER done that because the mods give it a big wooly low end, So I thought upping the bass would be too much, But.. It actually didnt make it flubby, but seemed to make the low end sweeter. When I would do harmonic squeals on the low strings now, I get a sweet bloom. NICE!!
Wonder how much it'll cost to get it to run el34s??
I must say this:
First, I did blast it for awhile today and Yeah, sounds huge when LOUD! Matter of fact, one of my daughters came home from school and said she hear me nearly 2 blocks away! Hee hee hee :naughty:
Second, I played with the EQ and got a beautiful sound out of it. I dialed the mids up to about 8 and I tried dialing the bass up.. Ive NEVER done that because the mods give it a big wooly low end, So I thought upping the bass would be too much, But.. It actually didnt make it flubby, but seemed to make the low end sweeter. When I would do harmonic squeals on the low strings now, I get a sweet bloom. NICE!!
Invader09
New member
Re: ProCo Rat ? Juicing a JCM800?
I'm not sure how much it would cost, but 6550's are much "louder" tubes, so putting in EL34's would also allow you to turn your amp up... 'slightly'
Basically, the power tube sockets would need to be re-wired. Also, possibly changing to a smaller output transformer could be a possibility after this, but not likely necessary. Ive heard the 800's that were intended for the US used 6550's and the ones for EU were EL34's but don't know all the details on that. I'd say $100-(including bias) + the cost for the EL34 tubes, for the mod.
I'm not sure how much it would cost, but 6550's are much "louder" tubes, so putting in EL34's would also allow you to turn your amp up... 'slightly'
Basically, the power tube sockets would need to be re-wired. Also, possibly changing to a smaller output transformer could be a possibility after this, but not likely necessary. Ive heard the 800's that were intended for the US used 6550's and the ones for EU were EL34's but don't know all the details on that. I'd say $100-(including bias) + the cost for the EL34 tubes, for the mod.
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Re: ProCo Rat ? Juicing a JCM800?
I'll tell you, its amazing how much difference eq tweaks make on this amp. The biggest suprise is the improvement made by turning up the bass. I never did because the mod on this gives a real wooly type of sound when the gAIN is dimed, so I didnt figure it needed more bass. But by turning it up, it doesnt really add low, it adds low presence (?). However you describe it, it sounds great and with the added mids, it sounds great! my washburn mg104 with the custom8 sounds unreal.. the c8s are even better thru this thing. And of course, with the kids in school and the spouse at work,I got some juice running thru it, so this amp is singing. The dog is NOT happy! Igot the tube screamer and delay going, Im having a ball!
I'll tell you, its amazing how much difference eq tweaks make on this amp. The biggest suprise is the improvement made by turning up the bass. I never did because the mod on this gives a real wooly type of sound when the gAIN is dimed, so I didnt figure it needed more bass. But by turning it up, it doesnt really add low, it adds low presence (?). However you describe it, it sounds great and with the added mids, it sounds great! my washburn mg104 with the custom8 sounds unreal.. the c8s are even better thru this thing. And of course, with the kids in school and the spouse at work,I got some juice running thru it, so this amp is singing. The dog is NOT happy! Igot the tube screamer and delay going, Im having a ball!
Invader09
New member
Re: ProCo Rat ? Juicing a JCM800?
HAHA !! Have fun man ! 800's are so sweet, makes me piss my diaper every time ! You said yours using a 2203 or was it a 2205 ?? How about giving my settings a try ? (of course I'm running through a dif. cab w/ dif. pups, but give a shot, and report back.
Presence 10 -- Bass 10 -- Mids 5 -- Treble 8 -- Preamp 10 -- Turn master up loud
HAHA !! Have fun man ! 800's are so sweet, makes me piss my diaper every time ! You said yours using a 2203 or was it a 2205 ?? How about giving my settings a try ? (of course I'm running through a dif. cab w/ dif. pups, but give a shot, and report back.
Presence 10 -- Bass 10 -- Mids 5 -- Treble 8 -- Preamp 10 -- Turn master up loud
