Hmm, stock JMP 2203

[Anonymous]

What do you guys recommend to make one of these tip top sounding in stock condition? Anything on the board that needs to be changed? Bias caps maybe..

What has worked for me and sounds bitchin.. like the amp with a bit more bite without changing the overall effect:

V1A - see that 10k cap, bypass it with either a .47, .68, .1 uf sozo or mustard. ( I like .1) You can drop the 10 k resistor to 4.7k as well but i found it buzzy. Def don't just drop it from 10k to 4.7k. You will want a bypass cap either way in my opinion. I just thought it sounded better.

V2A - Bypass the 820 ohm cathode resistor (V2A) w/ a .68uF cap in parallel. Tad more mid crunch. You can also up that 820 ohm resistor to 1 or 1.5 k. Those early CC resistors varied in what they actually measured so maybe some amps had more mojo as the value drifted and thus gain went up.

NFR- 100k in jcm800's/2204 in most cases..I like to drop it to 47k. A little looser less grit/tight buzz. While you are at it, move that NFR wire off the 4 ohm tap and onto the 8 ohm tap.

Depending on whether you like it at lower levels, snip that bright cap. Some amps it works perfectly, other amps, it needs snipping. Not sure why but be it component types used in a particular build or other, sometimes it needs snipping.

There it is. Bam. You'll love it. With the right pickups that is probably all you will need. For a little kick in the ass though, a smidget of boost for leads.

Now if that still isn't enough, try this out. http://www.sonicdeli.com/ThunderTweakWe ... l50.pdfThe values seem interesting but they also seem to push the first two stages to the limit! Can't promise it wouldn't be buzzsaw. I've never tried it as i like the formula above best. Amazing how simple and good this formula sounds. Sure the BE's of the world might sound better but this won't cost you 3000$+ , it will cost you 3$ in parts. (nothing against the BE-100, wish i had cash for one!!)

Dead link Kapo!

 

[scriptphase]

What do you guys recommend to make one of these tip top sounding in stock condition? Anything on the board that needs to be changed? Bias caps maybe..

What has worked for me and sounds bitchin.. like the amp with a bit more bite without changing the overall effect:

V1A - see that 10k cap, bypass it with either a .47, .68, .1 uf sozo or mustard. ( I like .1) You can drop the 10 k resistor to 4.7k as well but i found it buzzy. Def don't just drop it from 10k to 4.7k. You will want a bypass cap either way in my opinion. I just thought it sounded better.

V2A - Bypass the 820 ohm cathode resistor (V2A) w/ a .68uF cap in parallel. Tad more mid crunch. You can also up that 820 ohm resistor to 1 or 1.5 k. Those early CC resistors varied in what they actually measured so maybe some amps had more mojo as the value drifted and thus gain went up.

NFR- 100k in jcm800's/2204 in most cases..I like to drop it to 47k. A little looser less grit/tight buzz. While you are at it, move that NFR wire off the 4 ohm tap and onto the 8 ohm tap.

Depending on whether you like it at lower levels, snip that bright cap. Some amps it works perfectly, other amps, it needs snipping. Not sure why but be it component types used in a particular build or other, sometimes it needs snipping.

There it is. Bam. You'll love it. With the right pickups that is probably all you will need. For a little kick in the ass though, a smidget of boost for leads.

Now if that still isn't enough, try this out. http://www.sonicdeli.com/ThunderTweakWe ... l50.pdfThe values seem interesting but they also seem to push the first two stages to the limit! Can't promise it wouldn't be buzzsaw. I've never tried it as i like the formula above best. Amazing how simple and good this formula sounds. Sure the BE's of the world might sound better but this won't cost you 3000$+ , it will cost you 3$ in parts. (nothing against the BE-100, wish i had cash for one!!)

Dead link Kapo!

Take off "The" after .pdf in the URL and it will work:

http://www.sonicdeli.com/ThunderTweakWe ... Fuel50.pdf

 

[Jofipe]

What do you guys recommend to make one of these tip top sounding in stock condition? Anything on the board that needs to be changed? Bias caps maybe..

What has worked for me and sounds bitchin.. like the amp with a bit more bite without changing the overall effect:

V1A - see that 10k cap, bypass it with either a .47, .68, .1 uf sozo or mustard. ( I like .1) You can drop the 10 k resistor to 4.7k as well but i found it buzzy. Def don't just drop it from 10k to 4.7k. You will want a bypass cap either way in my opinion. I just thought it sounded better.

V2A - Bypass the 820 ohm cathode resistor (V2A) w/ a .68uF cap in parallel. Tad more mid crunch. You can also up that 820 ohm resistor to 1 or 1.5 k. Those early CC resistors varied in what they actually measured so maybe some amps had more mojo as the value drifted and thus gain went up.

NFR- 100k in jcm800's/2204 in most cases..I like to drop it to 47k. A little looser less grit/tight buzz. While you are at it, move that NFR wire off the 4 ohm tap and onto the 8 ohm tap.

Depending on whether you like it at lower levels, snip that bright cap. Some amps it works perfectly, other amps, it needs snipping. Not sure why but be it component types used in a particular build or other, sometimes it needs snipping.

There it is. Bam. You'll love it. With the right pickups that is probably all you will need. For a little kick in the ass though, a smidget of boost for leads.

Now if that still isn't enough, try this out. http://www.sonicdeli.com/ThunderTweakWe ... l50.pdfThe values seem interesting but they also seem to push the first two stages to the limit! Can't promise it wouldn't be buzzsaw. I've never tried it as i like the formula above best. Amazing how simple and good this formula sounds. Sure the BE's of the world might sound better but this won't cost you 3000$+ , it will cost you 3$ in parts. (nothing against the BE-100, wish i had cash for one!!)

Thanks allot for the info brother! I wasn't looking to modify it tho. The reason to get this was to have a great sounding stock amp, to which I can add a boost or an OD. It
I'm undecided yet... non of the amps can replace the other. The modded sounds more refined and "nice" in a more modern way, the Gower boing able to go really close to a stock 2203!. The stock is just nastier and easily recognizable on allot of the 80's heavy metal albums... even the Down - Nola album from 95. Maybe I should just talk to Dan and see if he can tweak my KK++ a bit... i'm sure he can when he has time.

 

[Kapo_Polenton]

What do you guys recommend to make one of these tip top sounding in stock condition? Anything on the board that needs to be changed? Bias caps maybe..

What has worked for me and sounds bitchin.. like the amp with a bit more bite without changing the overall effect:

V1A - see that 10k cap, bypass it with either a .47, .68, .1 uf sozo or mustard. ( I like .1) You can drop the 10 k resistor to 4.7k as well but i found it buzzy. Def don't just drop it from 10k to 4.7k. You will want a bypass cap either way in my opinion. I just thought it sounded better.

V2A - Bypass the 820 ohm cathode resistor (V2A) w/ a .68uF cap in parallel. Tad more mid crunch. You can also up that 820 ohm resistor to 1 or 1.5 k. Those early CC resistors varied in what they actually measured so maybe some amps had more mojo as the value drifted and thus gain went up.

NFR- 100k in jcm800's/2204 in most cases..I like to drop it to 47k. A little looser less grit/tight buzz. While you are at it, move that NFR wire off the 4 ohm tap and onto the 8 ohm tap.

Depending on whether you like it at lower levels, snip that bright cap. Some amps it works perfectly, other amps, it needs snipping. Not sure why but be it component types used in a particular build or other, sometimes it needs snipping.

There it is. Bam. You'll love it. With the right pickups that is probably all you will need. For a little kick in the ass though, a smidget of boost for leads.

Now if that still isn't enough, try this out. http://www.sonicdeli.com/ThunderTweakWe ... l50.pdfThe values seem interesting but they also seem to push the first two stages to the limit! Can't promise it wouldn't be buzzsaw. I've never tried it as i like the formula above best. Amazing how simple and good this formula sounds. Sure the BE's of the world might sound better but this won't cost you 3000$+ , it will cost you 3$ in parts. (nothing against the BE-100, wish i had cash for one!!)

Dead link Kapo!

FIXED! (in original ) post.. or here: http://www.sonicdeli.com/ThunderTweakWe ... Fuel50.pdf

 

[Kapo_Polenton]

Thanks allot for the info brother! I wasn't looking to modify it tho. The reason to get this was to have a great sounding stock amp, to which I can add a boost or an OD. It
I'm undecided yet... non of the amps can replace the other. The modded sounds more refined and "nice" in a more modern way, the Gower boing able to go really close to a stock 2203!. The stock is just nastier and easily recognizable on allot of the 80's heavy metal albums... even the Down - Nola album from 95. Maybe I should just talk to Dan and see if he can tweak my KK++ a bit... i'm sure he can when he has time.

Woops sorry man, I misread that. Essentially these mods don't really change the character of the amp at all. Just give it a tad more oomph and crunch. If you like the stock sound, don't bother with the filter caps until that sound stops pleasing you. Then think about changing them. Why fix what isn't broken yet?? So I will say don't touch a thing. Clearly the amp has mojo so let it keep it. Maybe swap some preamp tubes and find a good boost. SD-1, TS-9's, ZW-44 work well with this circuit. Or go more high end and grab one of the Suhr drives.

 

[charveldan]

Sounds great! Why the sale?

Too fucking LOUD ... My Friedman JMP's volume is much more managable and all i'll ever need.

 

[rlord1974]

Sounds great! Why the sale?

Too fucking LOUD ... My Friedman JMP's volume is much more managable and all i'll ever need.

Why didn't you just replace the Master pot with one that has a smoother, more gradual taper?

Or, attenuate!

 

[charveldan]

Sounds great! Why the sale?

Too fucking LOUD ... My Friedman JMP's volume is much more managable and all i'll ever need.

Why didn't you just replace the Master pot with one that has a smoother, more gradual taper?

Or, attenuate!

My Vintage guy down the street wanted it and i wanted to keep it stock. At one point i wanted Friedman to tweak it but it was awesome the way it was.
I never played it and it was time to pass it on. I got my $$$ back & then some.

 

[japetus]

Please don't mod it. There are a million amps out there that can do the hotrodded Marshall tone right out of the box. Please leave some of those amps for people that like them stock such as myself. The 80's already did enough damage.

 

[metalmaniac93]

Just send it to Dan for another Dan Gower mod to add to your collection!!!

 

[Jofipe]

JOSE JOSE JOSE JOSE!!! haha

 

[Shiny_Surface]

Please don't mod it. There are a million amps out there that can do the hotrodded Marshall tone right out of the box. Please leave some of those amps for people that like them stock such as myself. The 80's already did enough damage.

Reading some of the past comments about getting one of the "good" ones when buying old Marshall's to some means having a tone closer to the 80's right out of the box. I really do enjoy the straight in (what I call) 70's type classic rock crunch sound of mine though.

I can add the 80's with a few choice boxes, and take it away just as easily by clicking the pedals off.

I have had some modded Marshall's which were cool and all, everyone has their preferences.

But in this day and age you definitely don't need to find old Marshall's to mod to get the modded sound anymore imo.

 

[Jofipe]

Totally agree.. it would be a waste.

 

[ericsabbath]

Also he said the filter caps had been changed recently, but they dont have a brand on them. "plain black with values engraved in gold". Maybe I should just put in F&T's and see what happens.

this will change tone, and you might lose what you liked about it
this could be what made it stand out from the others (for your ears)

my fully modded '73 jmp is loaded with mysterious shady cheap parts and although I could change some of those (I have some spare JJ electrolytics, wima capacitors, carbon comp and low tolerance metal film resistors), I won't risk losing its unique tone
only swapped the first preamp coupling cap and the phase inverter caps for NOS mustards in lower values to get some of the true marshall sound back, as it was a little too bassy and modern sounding (and that worked way better than I expected!)
was thinking about tweaking the tonestack to tame the low end a little more and add some upper mids, but a simple tube swap in the first preamp positions did that easily (took out an old tungsram and a NOS german rft and put tung sols)

 

[Norton666]

I cant say that Ive ever seen a JMP that doesnt say JMP on the faceplate . Also , a JMP with the serial number on the front instead of the back . Something is ...off with that amp

 

[charveldan]

I cant say that Ive ever seen a JMP that doesnt say JMP on the faceplate . Also , a JMP with the serial number on the front instead of the back . Something is ...off with that amp

Pretty sure 79' and beyond the serial was located on the front.
My 78's were on the back but my 79' was on the front.

 

[Kapo_Polenton]

Please don't mod it. There are a million amps out there that can do the hotrodded Marshall tone right out of the box. Please leave some of those amps for people that like them stock such as myself. The 80's already did enough damage.

Reading some of the past comments about getting one of the "good" ones when buying old Marshall's to some means having a tone closer to the 80's right out of the box. I really do enjoy the straight in (what I call) 70's type classic rock crunch sound of mine though.

I can add the 80's with a few choice boxes, and take it away just as easily by clicking the pedals off.

I have had some modded Marshall's which were cool and all, everyone has their preferences.

But in this day and age you definitely don't need to find old Marshall's to mod to get the modded sound anymore imo.

Again though guys, that's if you get a good one. The mods I suggested can all be done without modifying the board, You just bypass with 2 caps and piggy back a resistor on the NFR. That's what i did with mine. I did however install an effects loop and i have an RFT in V1. Personally the amp stock with 6550's, sucked for me. Was stiff and a tad bright. So i have no problem with minor mods. We aren't talking hacking it up completely. My mods could be reversed in 3 moves. (except the loop)

 

[Schaf]

Please don't mod it. There are a million amps out there that can do the hotrodded Marshall tone right out of the box. Please leave some of those amps for people that like them stock such as myself. The 80's already did enough damage.

Reading some of the past comments about getting one of the "good" ones when buying old Marshall's to some means having a tone closer to the 80's right out of the box. I really do enjoy the straight in (what I call) 70's type classic rock crunch sound of mine though.

I can add the 80's with a few choice boxes, and take it away just as easily by clicking the pedals off.

I have had some modded Marshall's which were cool and all, everyone has their preferences.

But in this day and age you definitely don't need to find old Marshall's to mod to get the modded sound anymore imo.

Again though guys, that's if you get a good one. The mods I suggested can all be done without modifying the board, You just bypass with 2 caps and piggy back a resistor on the NFR. That's what i did with mine. I did however install an effects loop and i have an RFT in V1. Personally the amp stock with 6550's, sucked for me. Was stiff and a tad bright. So i have no problem with minor mods. We aren't talking hacking it up completely. My mods could be reversed in 3 moves. (except the loop)

Honestly, I've had a JMP and two JCM's. Still have one JCM. All three of them sounded great. One had 6550's. It sounded great as well. Maybe I got lucky for all three to sound good? I'd say as long as they haven't been fucked with, there's more good sounding ones than bad ones.

 

[MrDan666]

JOSE JOSE JOSE JOSE!!! haha