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PostPosted: Wed Jul 06, 2011 7:16 am 
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Negative feedback adjustment modification

Switchable: variable with pot/can be made switchable
Affects: All channels/modes - power section modification
Parts list:
- 1M logarithmic potentiometer
- 47k resistor
***
How to perform the mod:
- Replace R58 with a 47k resistor wired in series with a 250k linear pot.

MOD VARIANT: (now preferred method)
Larger value pot and smaller value resistor for more range when adjusting and even less negative feedback with the knob dimed.
Parts list
- 1M log potentiometer (log pot makes the adjustments finer but allows more range)
- 33k resistor
***
How to perform the mod:
- Replace R58 with a 33k resistor wired in series with a 1M linear pot.


MOD VARIANT:
Switchable stock feedback level and level of desired value
Parts list
- Switch with at least two positions
- resistors of desired value
***
How to perform the mod:
- Replace R58 with resistors of desired value wired to a DPDT switch or a multiposition switch (for example switch up=JVM stock (82k), switch down=JCM800 (176k)


MOD VARIANT: The Charlotte method -easier to do by modding the blue wire, not the components directly

The Charlotte method
Scroll thru the thread for Jims photos.


TRY FOR FREE ! Someone posted the idea of unplugging the blue wire which essentially gives you the vox+ setting, so you can try it for free [smilie=banana_smiley.gif] Doing the mod will give you the ability to go between stock and that vox+ setting.
Explanations/opinions:

Casey_Butt wrote:
When you decrease the amount of negative feedback two primary things happen. 1) the amp gets louder at lower volume settings because the power amp is not "limiting" itself. 2) The decreased feedback lets the power tubes break up sooner and more gradually - this is the important part.


Casey_Butt wrote:
A huge effect on dynamics, a fairly significant effect on tone as a result of how the power amp is working.


JBlackout wrote:
I have tried your Negative feedback adjustment knob, and it works well. After switching between the modes I decided me for the 2203 (176K) position. it has the most "Balls" really like a JCM800. [smilie=gt-happyup.gif]


marshalmellowed wrote:
All done, and I like it! Definitely adds some grunt and growl.


Andy wrote:
Conclusions: Gives a fuller sound, more dimensional and crunchy, a bit like turning the bias up.

Downsides are maybe for very high gain it isn't as controlled and clean is less clean, but it's more
interesting.


manicguitarist wrote:
The mod made, to me at least, the higher gain channels very mushy - which was similar to a sound that I had once when playing an outdoor gig and the amp was set to 7 or 8.


Possible downsides:
High gain tones might become less tight or lose definition.

The decrease of negative feedback will make your amp slightly louder (possible downside for bedroom players). The more you decrease the feedback, the louder the amp will become at low MV settings.

Notes:
RESISTOR VALUES of various Marshall amps
R58 = 47k -- late '60s Plexi
R58 = 74k -- early '70s MkII Plexi
R58 = 82k -- stock JVM
R58 = 137k -- EVH's Plexi
R58 = 176k -- JCM800 2203
R58 = 177k+ -- a Marshall with almost a Vox's lack of headroom in the power amp

For details, see this thread.

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
Proel Esoteric cables, Ernie Ball strings; Dunlop Ultex Sharp picks


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PostPosted: Wed Jul 06, 2011 7:37 am 
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Location: Slovenia, Europe
Choke modification

Switchable: can be made switchable
Affects: All channels/modes
Parts list:
- Choke of desired value
- High-voltage switch (preferably "make before break")
***
How to perform the mod:
- Replace R106 with a choke.


Explanations/opinions:

Quote:
Chokes are designed to block AC while passing DC. Their purpose in guitar amp filter supplies is to smooth out the ripple in the rectified DC. Using a choke in the filter supply the result is less background hum and cleaner, better bass response


svdijk wrote:
Good things:
The amp is smoother now, and reacts much better! The mids are sweeeeeet!!! The amp sounds bigger, because of the bigger and tighter lowend. And the lowend-thump is unbelievable. More harmonics.


atrox wrote:
I just got it back last night and I must say, it took care of any issues I had with my JVM. The bass is tighter, the cleans are warmer, the lead channels are more focused and tight, the crunch channel is less floppy, the gain is quieter and the thing sustains forever in any channel. Not that I would ever use them, but even the red channels on the lead channels are musical.

-----

I was playing it a bit more today with a couple different guitars. The amp definitely likes single coils a lot more now. Before, my Strat or Tele would be way too piercing without completely re-dialing in. It's a lot more natural now going back and forth between different guitars. My metal guitar tuned to straight C is just crushing.


Flameout12 wrote:
The biggest difference I can see is the choke has softened the pick attack so it is much more like the Plexi.
Before, it almost felt like I had put heavy gage strings on my guitar. Now it feels normal.


Andy wrote:
If you do the mod make it switchable as (for me) the choke in is better for bluesy classic rock and no choke (resistor) is better for heavier stuff and clean green.


Possible downsides:
The amp may feel too mellow or "saggy".

Notes:
Casey_Butt wrote:
An EL34-based amp with good breakup like the JVM can work with anything from 3H up to 10H or even more... the higher the Henries, generally the cleaner the sound and the tighter the bass


For details, see this thread.

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
Proel Esoteric cables, Ernie Ball strings; Dunlop Ultex Sharp picks


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PostPosted: Wed Jul 06, 2011 7:49 am 
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Location: Slovenia, Europe
The Plexi Cap Mod

Switchable: can be made switchable
Affects: All channels/modes
Parts list:
- .68uF or 1uF capacitor
***
How to perform the mod:
- Solder a .68uF or 1uF polyester capacitor in parallel with R97

Explanations/opinions:

Casey_Butt wrote:
The 1 uF cap in parallel with R97 does an absolutely beautiful job of taking any brittleness out of the high notes. With a pickup with a thick top-end it doesn't matter so much, but with a pickup that has a brittle high-end this can help turn the upper frets from harsh-ish to smooth and full. Again, it isn't dramatic, but you will notice that the higher notes are fuller and the brittleness improved/gone.


Andy wrote:
...probably the easiest mod to do and so far THE BEST MOD I have done, it really makes the OD channels sound like a modded JCM800 to my ears, smoother and less brittle/harsh than standard.


JBlackout wrote:
Ok, i tried the mod and love it! My JVM have a lot more life in it


Playing4JC wrote:
My notes are thicker or rounder and less shrill now after I had the 1uF cap mod done.


Possible downsides:
It might take a very small shade of clarity out of the high mids in clean tones (hard to notice).

Notes:
This mod's effect is subtle.

For details, see this thread.

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
Proel Esoteric cables, Ernie Ball strings; Dunlop Ultex Sharp picks


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PostPosted: Wed Jul 06, 2011 8:05 am 
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Location: Slovenia, Europe
C83 Removal mod

Note: if you are doing other mods like the "anti-compression" mod etc you will probably prefer C83 IN

Switchable: can be made switchable
Affects: Clean RED, OD1&2 ORANGE, OD1&2 RED
Parts list:
- cutting tool
- wire
***
How to perform the mod:
- Remove C83 (and use the now empty solder joints to put a switch in series with a new C83 if you want it switchable)

MOD VARIANT:
C83 value reduction instead of complete removal.
marshalmellowed wrote:
I find that the some of the best results come from using a capacitance value somewhere in between. I finally settled on these values for my 3 position switch:

Center - No Cap
Position 1 - .1uf
Position 2 - .22uf


Explanations/opinions:

Andy wrote:
It takes some of the high frequencies out on some modes / channels ...


Iced_tea wrote:
Just yesterday I removed the C83. In my ears it sounds much better. More marshallig. And still enough gain is available.


marshalmellowed wrote:
IMO, the original .68uf cap gives you a nice sharp pick attack (good for metal), but also gives the amp some fizziness at medium/high gain settings. Removing the cap completely gives a perceived drop in gain and gets rid of a lot of the fizziness (desirable for my tastes), but it also takes away a lot of the sharpness to the pick attack (undesirable for my tastes). A cap in the .1-.2uf range is a good comprimise for both, gets rid of a lot of the fizziness, but still retains a good pick attack.


GuitarDog wrote:
I have removed C83 several months ago and love it!


Casey_Butt wrote:
I put C83 back in the way it was ...didn't like the drop in gain and less harmonic content in the higher frequencies.


Possible downsides:
Loss of clarity and gain, could be undesirable.

Notes:
Combining with other mods may render the C83 removal mod unnecessary.
Andy wrote:
In my opinion the Casey Butt plexi and resonance mods solve the 'problem' that removing c83 addresses much better than removing c83. having all 3 mods I nearly always leave c83 switched in as it gives more detail.

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
Proel Esoteric cables, Ernie Ball strings; Dunlop Ultex Sharp picks


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PostPosted: Wed Jul 06, 2011 8:24 am 
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Posts: 5337
Location: Slovenia, Europe
OD2 to OD1 conversion

Switchable: no
Affects: OD channel
Parts list:
- 1n0 capacitor (1000pf)
- 3n3 capacitor (3300pf)
- 33k resistor
***
How to perform the mod (JVM2 Series):
- Change R44 from 47k to 33k
- Change C31 from 1n5 to 1n0
- Change C32 from 1n0 to 3n3

How to perform the mod (JVM410 Series):
- Change R220 from 47K to 33K
- Change C225 from 1n5 to 1n0
- Change C224 from 1n0 to 3n3

Explanations/opinions:

This modification turns the OD2 Channel of the JVM410 series or the OD Channel of the JVM2 series into the OD1 Channel of the 410 series, for a more "classic Marshall" tone.

Playing4JC wrote:
I can not explain technically what is going on, but I had my JVM205H modded to OD1 specs and I do have a lot more mids now. I am very happy with the mod. I am not a modern metal de-tuned guy in anyway. The more traditional Marshall voicing works much better for me.


manicguitarist wrote:
The difference,well, it now has OD1 instead of OD2. Which is the sound I prefer.


windsurf51 wrote:
Old OD2 was not so awful but not exactly what i want so i decided to do the mod : good idea [smilie=gt-happyup.gif]

For me, the sound is more natural , i can add middle and treble easily , overall sound is less harsh/trebly


Possible downsides:
None

Notes:
Playing4JC wrote:
They are low voltage 3n3 caps if anyone else does the mod.


For details, see this thread.

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
Proel Esoteric cables, Ernie Ball strings; Dunlop Ultex Sharp picks


Top
 Profile  
 
PostPosted: Wed Jul 06, 2011 8:34 am 
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Joined: Sun Mar 07, 2010 7:35 am
Posts: 5337
Location: Slovenia, Europe
1959 Crunch channel Mod

Switchable: partially (see thread for details)
Affects: Crunch Green (410H)
Parts list:
- 1uF cap
- 330k resistor (optional)
- 2.2nF polyester cap
- 4.7nF ceramic disk cap
- 430pF to 470pF ceramic disk cap
***
How to perform the mod:
- Solder the 1uF cap in parallel with R97 (plexi mod)
- Replace C229 with the 2.2nF polyester cap
- Replace C231 with a 4.7nF ceramic disk cap
- Solder the 430pF to 470pF ceramic disk cap in parallel with C217
- Change R240 from 470k to 330k (optional)
Casey_Butt wrote:
If you want to thicken those lower mids a little for the non-master volume type frequency response use a 330k resistor in the R240 spot. Otherwise, if you like the slightly thinner lower mids sound of the master volume heads (which was popular in a lot of early '80s music) then leave R240 alone. There's not a world of difference either way, but you might find it noticeable.


MOD VARIANT:
Put the 430pF to 470pF cap through a 10M potentiometer for a "high mid" pot.
Casey_Butt wrote:
I put the cap through a 10 Meg pot and put it on the front panel as a "high mids" knob - all the way down and it's removed from the circuit and the mids are stock. All the way up and the high-mids are boosted to a typical Plexi's bright channel (boosts from around 400-3000Hz).


Explanations/opinions:

This mod will turn the JVM Crunch Green channel into an (almost) Plexi clone.

Casey_Butt wrote:
The results are exactly what you'd expect... tighter bass than the JVM stock Crunch channel, more high-mids, more "growl" and more even tone through the sweep of the gain knob. In comparison to the '73 JMP the JVM "Plexi mode" has a shade more bass and sounds perhaps a little thicker in the lower notes at low volumes (thanks to stronger second-order harmonics). At high volumes, power tube and transformer distortion starts dominating and it's not really comparing preamp to preamp anymore. Having said that, the JVM has a better designed power amp than the Plexi in every regard, though the differences in function are fairly slight. The C229 and R97 cap switches, and the high-mids knob, are there so you can go back to almost stock JVM Crunch channel in a second.


Andy wrote:
The modded channel seems to have more dimensions to it and more grunt* [smilie=icon_biggrin.gif]

*BASED ON PROVIDED CLIPS

Possible downsides:
You lose the bone-stock Crunch Channel.

Notes:
For details, see this thread

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
Proel Esoteric cables, Ernie Ball strings; Dunlop Ultex Sharp picks


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 Profile  
 
PostPosted: Wed Jul 06, 2011 8:34 am 
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Location: Slovenia, Europe
2203 OD1 Channel Mod

Switchable: partially (see thread for details)
Affects: OD1 Channel
Parts list:
- 1uF polyester cap
- 4.7nF polyester cap
- 470pF ceramic disk cap (3x)
- 470k resistor
- 0.68uF cap (100V minimum) and 0.33uF cap (optional)
- DPDT switch (2x) - optional
***
How to perform the mod:

FRONT PANEL BOARD:
- Solder the 1uF polyester cap across R97 (plexi mod)
- Replace C204 with the 4.7nF polyester cap
- Solder a 470pF ceramic disk type cap in parallel with R203
- Lift the lower pin of C205 (disconnect it on the C204/R203 junction side) and attach it to the upper leg of R203 (at the junction with the VR205 pot). (It will be easier to do this if you remove C205 completely and do the mods on the back of the board rather than as usual on the top)

MAIN BOARD:
- Replace C44 with a 470pF ceramic disk type cap
- Replace R129 with a 470kohm resistor and put a 470pF ceramic disk type cap across in parallel with this resistor. This is the JCM800 treble-peaker after the second clipping stage.
- OPTIONAL switchable component
Casey_Butt wrote:
If you want to be able to switch back to the stock JVM configuration put the 470pF cap on a DPDT switch so you can switch it in and out of the circuit; across the other side of the switch put a 120 to 130 kohm resistor and connect the side of the resistor closest to C77 through a 470pF capacitor (ceramic disk type) to ground - you can use a convenient ground point on the preamp side, I used the ground side of R98. This will allow you to switch the JCM800 treble-peaker in and out of the circuit, going back to stock when you wish.

- Replace C52 with the 0.68uF cap (100V minimum)
- OPTIONAL switchable component
Casey_Butt wrote:
Wire a 0.33uF cap in parallel with this cap on a DPDT switch. Wire it so that when the switch is down it's the 0.68uF + 0.33uF = 1.01uF setting, i.e. stock, and when the switch is up it's 0.68uF alone. This cuts the bass through the preamp a shade and makes it more like a true JCM800. However, the JCM800 circuit also works fine with the shade more bass that the stock C52 value (1uF) allows through. Keep in mind that this is a global mod and will affect all channels, so keep the switch up for stock JVM tones.


MOD VARIANT:
Modifying OD2 instead of OD1.
Parts list:
- 33k resistor or 120k resistor
- 4.7nF polyester cap
- 470pF ceramic disk type cap (3x)
- 1nF ceramic disk type 1nF
- DPDT switch (optional)
- 120k to 130k resistor (optional)

FRONT PANEL BOARD:
- Replace R220 with a 33k resistor or put a 120kohm resistor across in parallel with the stock R220.
- Replace C224 with a 4.7nF polyester cap.
- Solder a 470pF ceramic disk type cap in parallel with R234.
- Replace C225 with a ceramic disk type 1nF cap but attach the lower pin of the "new" C225 (the pin on the C224/R234 junction side) to the upper leg of R234 (at the junction with the VR215 pot). It will be easier to do this if you remove C225 completely and do the mods on the back of the board rather than as usual on the top.

MAIN BOARD:
- Solder a 1uF polyester cap across R97 (plexi mod)

- Replace C44 with a 470pF ceramic disk type cap .

- Replace R129 with a 470kohm resistor and put a 470pF cap (ceramic disk type) in parallel with this resistor. This is the JCM800 treble-peaker after the second clipping stage.
- OPTIONAL switchable component
Casey_Butt wrote:
If you want to be able to switch back to the stock JVM configuration put the 470pF cap on a DPDT switch so you can switch it in and out of the circuit; across the other side of the switch put a 120 to 130 kohm resistor and connect the side of the resistor closest to C77 through a 470pF ceramic disk type cap to ground - you can use a convenient ground point on the preamp side, I used the ground side of R98. This will allow you to switch the JCM800 treble-peaker in and out of the circuit, going back to stock when you wish... I highly recommend installing the treble-peaker switch because you may favour it in the Orange and Red modes (the more clipping there is the more treble attenuation you need to filter out harsh high frequency harmonics).


MOD VARIANT:
Increasing the lower midrange even more.
Parts list:
- 10nF Polyester Cap, 63v Minimum (x2; 1 for each channel)

FRONT PANEL BOARD:
- Change C202 to 10nF (for OD1)

- Change C223 to 10nF (for OD2)


Explanations/opinions:

This modification turns the OD1 Channel's voicing into a 2203 JCM800 type voicing.

Casey_Butt wrote:
The amp should have just slightly stronger lows and low-mids than a JCM800 as the gain is turned back if you don't mod C52


On the "more low mids" mod variant:
Casey_Butt wrote:
The "traditional" way of increasing bottom end is simply to swap in a larger value coupling cap at the front of the circuit, but with the amount of gain available on the JVM that just makes things too muddy. If I were going after more bass and low-mids on the JVM - especially when modded to a 2203 type response - I'd look to the mids caps in the tone stacks. In OD1 and OD2 that means decreasing C202 and C223 to 10n instead of the stock 22n. That will significantly boost the bass and low-mids, but should leave the low-bass alone enough to keep things tight.


Casey_Butt wrote:
In comparison to the original OD1 you’ll notice the channel now has a distinct JCM800 flavour. The tone is sharper and more cutting and there’s more of a distinct ‘80s tone to it. The OD1 Orange and Red modes now become a modified JCM800 with an extra gain stage. With the treble-peaker switched off these modes might become a little muddy, but in JCM800 mode with the treble-peaker on these modes stay tighter and more cutting – with the bass dialed back a shade it’s very Faith No More-ish (remember them?) or Slayer-ish in the "JCM800 channel" Orange and Red modes. Overall, there's a clear increase in "ooomph" from this channel now - that's not much of a technical description, but it's the best one that comes to mind.


Possible downsides:
You lose the bone-stock OD1 Channel.

Notes:
THIS MOD REQUIRES THE REMOVAL OF BOTH AMP AND FRONT PANEL PCBs.

Casey_Butt wrote:
A Note about Resistors: Early Marshalls used carbon comp resistors, but I don't recommend that for the signal path in the JVM. The reason is carbon comp resistors tend to be noisy and that doesn't work well in a high-gain capable amp like the JVM. For the lowest noise use metal film resistors (they are more stable also). If you don't plan on using the higher gain modes and just plan to stick with the "Plexi Green" and "JCM800 Green" channels then it won't matter much, but in the Orange and Red modes you'll need the least additional noise possible. I don't think you can tell the difference in tone anyway.


For details, see this thread

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
Proel Esoteric cables, Ernie Ball strings; Dunlop Ultex Sharp picks


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 Profile  
 
PostPosted: Wed Jul 06, 2011 8:35 am 
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Location: Slovenia, Europe
Fender "Blackface" Clean Channel Mod

Switchable: no
Affects: Clean Channel
Parts list:
- 200pF cap
- 47nF cap
- 20k resistor
- 120pF cap (needed for OPTION 1)
- 1uF polyester cap
- 3.3uF cap
- DPDT switch
***
How to perform the mod:
- Solder a 200pF cap in parallel with C209
- Replace C207 with a 47nF cap
- Solder a 20 kohm resistor in parallel with VR208 (from the C208 junction of the pot to ground)
- OPTION 1: replace C219 with a 120pF cap (Fender Blackface with Bright switch = ON)
- OPTION 2: remove C219 entirely and jumper from the pot side (VR209) of C209 to the pot side (VR210) of where C219 used to be (Fender Blackface with Bright switch = OFF, use JVM's Presence to add brightness).
- Solder a 1uF cap in parallel with R97 (plexi mod)
- SWITCHABLE COMPONENT:
Install a 3.3uF cap in parallel with C52 through a DPDT switch. Wire it so that when the switch is up the 3.3uF cap is in parallel with C52 for a total of 4.3uF (3.3uF + 1uF)
Switch UP (total value 4.3uF): bass boost starting at 40Hz
Switch DOWN (total value 1uF): no bass boost, response similar to brighter Blackfaces such as a Twin Reverb.

Explanations/opinions

This modification turns Clean Green into a Fender Blackface-style channel.

Casey_Butt wrote:
These mods give a very convincing blackface tone. In fact, with the Fender Super Reverb RI (with the 32uF mid cap) and the "blackface modded" JVM side-by-side the biggest factor in terms of tone difference I get between the two seems to be due to the cabinet and speakers. When I run the JVM head through a 2x12 open-backed cabinet with Fender speakers from the late 1980s (actually a version of Eminence Legends) the two amps are very close. In all honesty, I prefer the JVM though, because it has a little more "punch" and thickness in the bass as well as a seemingly shade clearer top end ...probably because of the JVM's higher supply voltage.


Casey_Butt wrote:
...the extra bass really warms up the clean tones and gives the clean channel a smoother and noticable blackface quality. If you play a lot of cleans, and want the blackface tone, these mods will get you there to a very close degree ...perhaps indistinguishable were it not for the EL34 power tubes


hotthands wrote:
It's not so much true Blackface tones per se, it's the full and warm, but still clear part that I was after. That being said there isn't much clean going on in any of the stuff we do, but if you take Seether's "Truth" for example, the clean behind the opening verse with this mod and a touch of 'verb and chorus is just glorious to my ears. This is where the added thickness and roundness comes in. Again all of this is subjective as we don't all hear things the same, I like to tinker and tweak, so I do! As they say "your mileage may vary"... in the end I'm very happy with it, and yes, "because I can" is also part of the equation! [smilie=icon_biggrin.gif]
banana_rasta


Possible downsides:
You lose the bone-stock Clean Channel.

Notes:
THIS MOD REQUIRES THE REMOVAL OF THE FRONT PANEL PCB.
Casey_Butt wrote:
Clean Orange and Red channels work well also. The extra bass requires dialing back the bass knob a little, but the bass tone knob still has enough range to dial it in as you like ...and you can always cut the bass by flipping the bass boost off on the DPDT switch.


Using KT77 power tubes may bring you closer to the Blackface tone than EL34 tubes (but will, of course, affect the rest of the amp).

For details, see this thread.

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
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PostPosted: Wed Jul 06, 2011 9:48 am 
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MESA/Boogie Dual Rectifier OD2 Channel Mod

Switchable: no
Affects: OD2 Channel (slight effect on OD1 Orange/Red as well, see thread for details)
Parts list:
- 1uF polyester cap (optional)
- 120pF cap
- 2.2nF cap OR 3.3nF cap
- 0.33uF cap
- 220pF cap
- 1nF cap
- 82k or higher value resistor (higher value=more brightness)
***
How to perform the mod:
MAIN BOARD
- Solder a 1uF cap in parallel with R97 (plexi mod); optional
- Solder a 120pF cap in parallel with R128
- OPTION 1: replace C224 with a 2.2nF polyester cap; for darker/muddier guitars
- OPTION 2: replace C224 with a 3.3nF cap; for brighter/tighter guitars
- Solder a 0.33uF cap in parallel with R116; optional
!!!
Casey_Butt wrote:
The result will be a slight boost in the low-mids and lows. But be aware that if you do this it will also slightly boost the low-mids and lows in OD1 Orange and Red modes as well.
!!!
- Solder a 220pF cap in parallel with C211

FRONT PANEL
- OPTION 1: Solder a 1nF cap in series with a 82k resistor (solder them close together) and then take this "circuit" and solder it from the VR211 pot side of R233 to the ground pin of VR213 (the fourth pin over and you can see where it's connected to the ground plane on the back of the board)
- OPTION 2: Use a higher value resistor (for example 120k) if you find the tone to be too dark (author preference: 100k)

Explanations/opinions:
This modification turns the OD2 Orange and Red channels into what is essentially the highest gain channel of a MESA/Boogie Dual Rectifier.

Casey_Butt wrote:
With all that done, try bass on 6, mids on 2, treble on 7 to 7.5, presence on 5, and gain on 5 in "Rectifier modded" OD2 Red and you'll get an extremely thick, aggressive Dual Rec type metal tone, with a touch of Marshall EL34 flavour. Brutal.


Casey_Butt wrote:
The modded OD2 Red is very, very aggressive. I don't think it's possible to make it sound pretty at all ...way too much chunk, djent, etc. But what a metal machine, I think Eric Peterson would piss himself and run away from this one. OD2 Green and Orange are like OD1 Green and Orange except thicker and more scooped sounding.


Possible downsides:
None (loss of stock channels)

Notes:
THIS MOD REQUIRES THE REMOVAL OF THE FRONT PANEL PCB.

The front panel part of the modification must be performed on the BACK of the circuit board, not the front.

Casey_Butt wrote:
If you add the 0.33uF cap on R116 it will boost the low-mids in OD1 Orange and Red as well, but that would be subtle, AND if you have the "Plexi mod" done (or do it) the resultant frequency response will be almost identical to stock OD1 because everything gets boosted about the same


For details, this thread.

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
Proel Esoteric cables, Ernie Ball strings; Dunlop Ultex Sharp picks


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PostPosted: Thu Jul 07, 2011 9:48 am 
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OD2 to OD1 Conversion EQ Curve (from Santiago himself)
Switchable: yes
Affects: channels with engaged Parallel FX Loop/all channels with engaged Series Loop
Parts list:
- EQ pedal of choice
***
How to perform the mod:
- set the EQ as pictured below (as close as you can get)
Attachment:
File comment: OD2 to OD1 Conversion curve
OD1-OD2.jpg
OD1-OD2.jpg [ 95.89 KiB | Viewed 16180 times ]

- OPTION 1: place EQ in the Parallel Loop (MIX=100% WET) and program your JVM head so that all the OD channels have the FX loop engaged; thus leaving the modes with disengaged FX loop intact
- OPTION 2: place EQ in the Series Loop and engage/disengage the EQ manually when needed

Explanations/opinions

This is not a true modification, but it is an easy way to gain the OD1 voicing without voiding the warranty or opening the amp; also, the stock OD remains available.

Surfcaster wrote:
It's weird in that it's fairly subtle, yet significant at the same time. Your average listener would probably not notice the difference, but it does just warm the tone up slightly and no doubt it will cut through a mix better. I'm not sure the difference is quite as stark as I remember it being between OD1 and OD2 on the 410, but then I don't have a 410 anywhere close by to compare it, too. But then the EQ is not the only difference between the two channels. And I'm guessing a 10-band EQ pedal would probably be slightly more effective...with my pedal I cannot adjust any values lower than 100 kHz or higher than 6.4 kHz, and there are some differences there*


*EQ USED: BOSS GE-7

Possible downsides:
Must use external EQ in either loop at all times.

Notes:
N/A

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
Proel Esoteric cables, Ernie Ball strings; Dunlop Ultex Sharp picks


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PostPosted: Fri Jul 08, 2011 7:16 am 
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Posts: 5337
Location: Slovenia, Europe
OD Channel Gain Reduction Mod

Switchable: no
Affects: OD Channel(s)
Parts list:
- 250k to 1M linear pot
***
How to perform the mod:
- Solder a 250k to 1M linear pot in parallel with R128

MOD VARIANT:
Hardwired resistor instead of the pot
Parts list:
- 100k resistor (or other value, see below)
How to perform the mod:
- Solder a 100k or other value resistor in parallel with R128

OR

- Solder a 100k or other value resistor from R94 (on the R128 side) to ground



MOD VARIANT:
Gain reduction for the JVM1 50th Anniversary mini-amp
Parts list:
- 220k resistor (or other value, see below)
How to perform the mod:
- Solder a 220k or other value resistor in parallel with R33

chris95 wrote:
this is the way and it sound GREAT!!!!
The sound is more open with less compression and for the gain use, before the mod I never turn it up more than 3 and half, now it seems to me I can go to 6 and more! It sound close to my JVM 205h (orange OD)
I'm very happy!!


Explanations/opinions:

Casey Butt wrote:
You can wire a 250k to 1M pot in parallel with R128 and it will act like an additional gain pot for just the OD1/2 Orange and Red modes - then you can adjust the gain exactly how you want it in those modes to balance with OD1/2 Green and the rest of the amp, or even silence the OD1/2 Orange and Red modes completely by turning the pot all the way "off".


This modification will lower the gain on the OD channel by about 2 "notches" on the Gain knob.

Casey_Butt wrote:
A smaller value resistor will drop the gain more and a bigger one less.


S&M Freddy wrote:
It works perfectly! I had the gain up from about 3 to about 5.5 on orange to achieve about the same level settings. Green is now usable for a more AC/DC type tone at the same master level. I think it has made the sound a bit rounder on Orange too. I am very pleased. The change is not huge but probably enough


Flameout12 wrote:
I did this mod and have been playing with it for about a week. I used a 100k and just piggy backed it onto the R128. With my gain on 5, my OD-O is about the same as early EVH, but I now set the gain to 7. My OD-R is very usable on 7 and both OD-O/R are usable modes depending on what I'm playing. I don't play any modern metal, so OD-G works for lots of rhythm and the other modes can be used for leads.


Possible downsides:
None

Notes:
Casey_Butt wrote:
Connecting to the other end of R94 will do something similar, but won't lower the gain as much and will shave some bass off. That's why I specified the R128 side. Connecting on the R128 side will simply drop the signal going into the third tube stage in OD Orange and Red modes, but shouldn't have a significant effect on the tone (though techincally it does shave off the highs a tiny, probably undetectable, bit) - it's basically the same as installing a fixed gain pot right there at that spot.


Casey_Butt wrote:
With the pot all the way off you'd be giving the signal a direct path to ground, so the OD1/2 Orange and Red modes would be silent. Essentially, it's simply another gain knob in the OD1/2 channels just for the Orange and Red modes.


For details, see this thread.

For a picture of the modification, see this thread

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
Proel Esoteric cables, Ernie Ball strings; Dunlop Ultex Sharp picks


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PostPosted: Fri Jul 08, 2011 7:24 pm 
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Location: Slovenia, Europe
Anti-stiffness Mod

Switchable: no
Affects: the whole amp
Parts list:
- 3H choke
- 100uF cap (rated for at least 400V each) (2x)
***
How to perform the mod:
- Replace R106 with a 3H choke
- Replace C50 with a 100uF cap (rated for at least 400V)
- Replace C81 with a 100uF cap (rated for at least 400V)

MOD VARIANT
Using a larger choke to get a similar, though not identical effect
Parts list
- 10H choke
- 32uF caps (rated for at least 400V each) (2x)
***
How to perform the mod:
- Replace R106 with a 10H choke
- Replace C50 with a 32uF cap (rated for at least 400V)
- Replace C81 with a 32uF cap (rated for at least 400V)


Explanations/opinions

Casey_Butt wrote:
Along with the negative feedback adjustment mod, this will make the JVM as dynamic and "alive" as any classic rock amp


Spacerocker wrote:
1st test was with a strat. Going through my old 4x12 cab, the sound was amazingly warm and sweet, with a surprising amount of bottom end! Great interaction between how hard the guitar is played and the sound that comes out of the speakers!

Next was my Les Paul - Wow! What a sound! Ultimate rock tone! I don't think I have heard a better rock guitar sound anywhere!


retrojet wrote:
Okay, used the amp today at practice and really got to put it to the test...I can now say that I have my ultimate amp! I know it's not just this mod and a combination of several mods including this one, but man this was the big fat cherry on top. It's never sounded more alive, and bandmates were bigtime impressed to. This is the sound in my head, the tone I've always been looking for. And it was equally awesome on each channel! It seems to have a little more gain overall now but not in just a "gainy" sense; I mean that my AC/DC tone lives on crunch orange now where it was crunch red before...my Motley Crue is now crunch red where it was on OD1 orange before...etc; the tones I use are just perfect now...it's like the gain is so much more open and raw that it sounds even better with lower gain than I had it (and it was dialed down below 5 anyways). I have the best early VH tone I've ever had now!

YMMV, and this mod probably isn't for everyone, but if you did the choke mod and neg feedback mod because you were looking for something that those would provide, then this mod is an absolute must to get you there. [smilie=gt-happyup.gif]


ach91 wrote:
Ok well I gave it a shot and based off of what I can tell from cranking my amp in just the bedroom and not in a band situation I can tell that the amp is a little more dynamic and open. To everyone who was curious about the bottom end getting flubbed out then dont worry about it because I dont feel that the bottom end is any looser feeling. And another thing like Casey said once you get into higher gain territory you tend to lose what you gain by doing the screen cap swap however it has helped my Crunch channel even more Plexi-like and despite the high gain thing I just said I can still detect it working on my OD/JCM 800 channels but its just not as dramatic as you would think.


Cron wrote:
I have removed the stiffness mod caps and reinstalled stock. The amp just punches harder stock i.m.o.


Andy wrote:
I changed out the caps (anti stiffness) but preferred it with the originals in


Possible downsides:
None.

Notes:
THIS MOD REQUIRES THE REMOVAL OF THE MAIN BOARD

Casey_Butt wrote:
In case you're wondering, this will not significantly affect the amp's bottom end - the bigger caps (220uF each) on the mains (C51 and C82) keep the lows big and tight.


Casey_Butt wrote:
Caps are 22mm in diameter, so most radial lead electrolytic caps rated for at least 400v and 22mm wide or less should do the trick.
I mention the diameter of the caps because you don't want to get too big ones or they might not fit in the space. That said, most "standard" 400V 100uF electrolytics should fit.


For details, see this thread

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
Proel Esoteric cables, Ernie Ball strings; Dunlop Ultex Sharp picks


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PostPosted: Fri Jul 29, 2011 6:24 am 
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Location: Slovenia, Europe
The Plexi "one wire" cascade mod - 3rd stage bias adjust knob

Switchable: yes/pot adjustable
Affects: all channels (most noticeable on Crunch Orange/Red)
Parts list:
- 820 ohm resistor
- 10k linear pot
***
How to perform the mod:
- Remove R96 and replace it with a 820 ohm resistor wired in series with a 10k linear pot.

Explanations/opinions

Casey_Butt wrote:
The effect that this mod has can go from just noticeable to much more obvious. In higher gain channels - like OD1/2 Orange and Red - it will be subtle, but in Crunch Orange and Red and Clean Orange and Red, it will give you the ability to go from a very "raw" and aggressive distortion character (with the knob turned up) to a smoother, more "classic" distortion with the knob turned down.


Possible downsides:
None

Notes:
Casey_Butt wrote:
Be aware that there is DC current flowing through the pot on the cathode, so you will hear a crackling noise when you adjust the knob. Obviously, it only happens while you're turning the knob and is silent when you stop turning it. It is not a loud crackling, but it's there.


Casey_Butt wrote:
Also, because this tube stage has a fairly low plate voltage as-is, I wouldn't recommend using a larger than 10k pot. Even with the 10k pot + 820 ohm resistor you may be able to bias the tube into cut-off with the knob all the way up ...particularly if you have on out-of-spec pot that measures more like 11k or 12k, rather than the advertised 10k. Measure your pot to be sure. In any case, even if you do bias the pot into cut-off the amp won't go silent or anything, you'll just notice a slight microphonic hiss in the background noise - it isn't dramatic but it's noticeable


For details, see this thread.

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
Proel Esoteric cables, Ernie Ball strings; Dunlop Ultex Sharp picks


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PostPosted: Mon Aug 01, 2011 6:32 am 
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The #34 Mod

Switchable: no
Affects: all channels
Parts list:
- 2200pF cap
- 0.47uF cap (2x)
- 150k resistor
- 0.1uF cap
- 470k resistor
- 470pF ceramic disk type cap (min 2x, max 3x)
- 220k resistor
- 1k resistor
***
How to perform the mod:
FRONT PANEL BOARD
-Put a 2200pF cap in parallel with R203
-Lift the lower pin of C205 (disconnect it on the C204/R203 junction side) and attach it to the upper leg of R203 (at the junction with the VR205 pot). It will be easier to do this if you remove C205 completely and do the mods on the back of the board rather than as usual on the top.

Attachment:
jvmjcm800gaincircuit34.jpg
jvmjcm800gaincircuit34.jpg [ 38.17 KiB | Viewed 19158 times ]


MAIN BOARD
- Replace C52 with a 0.47uF cap
- Replace R95 with a 150K resistor
- Put a 0.1uF cap in parallel with R96
- Replace R129 with a 470k resistor and put a 470pF ceramic disk type cap in parallel with this resistor
- Remove C44 or replace it with a 470pF cap (to keep the highs controllable in the OD Orange and Red modes)
- Replace R98 with a 220k resistor.
- Replace R97 with a 1k resistor and put a 0.47uF cap in parallel with this resistor.
- (Leave the tone stack stock)

Explanations/opinions

Casey_Butt wrote:
With these mods done the amp will be much stronger in the high-mids with the low-mids and bass filtered off - more nasally and raw, like Slash's UYI sound. In fact, the modeled frequency responses are very nearly identical from the input stage right through to the power tubes.


Possible downsides:
Entire amp will be affected by the mod which may or may not be desirable.

Notes:
THIS MOD REQUIRES THE REMOVAL OF BOTH FRONT PANEL AND MAIN PCBs.
Casey_Butt wrote:
For a true 2203 #34 type response you'll have to do the negative feedback adjustment mods as well (viewtopic.php?f=7&t=4467&start=0) because the 2203 had less negative feedback than the JVM and #34 was further modded to have less negative feedback than a stock 2203 (but well within range of the adjust knob with the mods).


Casey_Butt wrote:
If you replace C44 with a 470 pF cap the extreme highs shouldn't be quite as piercing as the actual #34, but the transformer and speakers don't reproduce those frequencies well anyway, so it might not be that noticeable but may help keep some harshness out of the OD Orange and Red modes.


Casey_Butt wrote:
The modded JVM will have a little more gain on tap through the preamp than the actual SIR #34.


For details, see this thread.
***

See this thread for an updated way of performing the mod

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
Proel Esoteric cables, Ernie Ball strings; Dunlop Ultex Sharp picks


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PostPosted: Wed Aug 24, 2011 3:11 pm 
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Posts: 5337
Location: Slovenia, Europe
Andy's pictures of Casey_Butt's mods

_________________
Bam Bam wrote:
Where's the little angel on the other side saying, "No, Bill, you should spend your hard-earned money on something more sensible and responsible [than another amp]."?
Oh yeah, wrong forum!


GUITARS:
Explorer w/Nailbombs; Yamaha SG2000; Gibson SG '61 Reissue; Ibanez RG370DX w/DiMarzios; Squier Classic Vibe Tele;
Yamaha LLX6A
AMPS&CABS:
Marshall JVM410H (EH in V1, V5/Chinese 12AX7 V2-V4; -ve fdbk mod, choke mod, plexi mod)
MESA 2:90+TriAxis (TungSol V1, EH V2, JJ V4); Marshall 1960A cab w/V30; Marshall MC212 cab w/G12T-75; Yamaha THR10
FX:
BOSS GT-6; Dunlop crybaby w/tb
OTHER STUFF:
Proel Esoteric cables, Ernie Ball strings; Dunlop Ultex Sharp picks


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