I want to talk more 5150 mods (my findings)
Posted: Wed Oct 26, 2011 10:40 am
I have modded 6 5150s so far and one 5150 2.
My amps have gotten pretty stellar reviews so far. I had to close my retail store but we were an authorized service center for all the major brands and I had access to all the schematics.
My typical mod package for a 5150 is:
1. Add adjustable bias.
2. Use matched output tubes. I prefer Ruby's and TADs even though I have yet to try very many Russian output tubes (we are a dealer for Ruby and TAD).
3. Tone stack the 12ax7s to (from V1 to the end): EHX, Mullard, Mullard, EHX, JJ or MUllard.
4. Add 10 pf cap to remove hiss
5. R9: piggyback a resistor on top of the 1 meg resistor. I have a peg board and I use clips to find the resistor that gives me the right amount of saturation reduction). I have a board that goes from about 100k to 250K. I use as little reduction as possible. This is one of the main mods to reduce hiss also.
6. 40H Hammond choke- this mod does nothing a room volumes (really) but with two to four 4x12's and the amp set to 8 ohms and loud it is a massive improvement!!!
I also run a 10 band EQ in the loop. THIS SHOULD BE IN THE CIRCUIT!!!! This amp is 50% better with an EQ in the loop... Eq' ing the power amp side of ANY amp is an improvement... I am looking at a way to mount the eq in the amp....
Here is what I found...
First off. If you want to sound like a Boogie, buy a Boogie... I recommend the Triple Rec... The 5150 is a modded Marshall, and the more you jack with the thing the more you realize that... I can add one resistor and nail the "Heading Out to Highway" JMP tone exactly. You can hear the basic tone signature. The Soldano is a modded Marshall also, same as the 5150. The Boogie is different and does not sound like a Marshall to me at all...
1. I do not use the "presence". It is set on zero. There is nothing good coming from this knob. Most of the "fizz" or "brittleness" in this amp comes from the presence. It appears to be a "resonance" for a treble notch that makes the amp sound like crap. If you really bear down and try to capture all the great tones from modded Marshalls in the past, this knob RUINS IT!!!
2. Bottom cabs have way more bottom end than slants, and sound "correct" to my ears... IF YOU PLAY DROP TUNING GET A SLANT!!!
3. Slants has more projection than bottoms, and do not get boomy like bottoms. See #2.
4. People use way too much f@@kin gain... They keep looking for "clarity" while using 14 layers of gain... The EQ in the loop with improve the gain better than more gain... It makes the amp come alive.
5. For reals.... A tube 100 watt amp does not sound worth a shit on one 4x12. The speakers are really overloaded. A 4x12 alone is really best suited to 50 watts or less... I use two and EVH used 4... The 5150 really starts changing character when the speaker load is upped after the bias is set correctly.
6. Once the EQ is the loop the lead channel can get a bassy as you want... JUST BRUTAL!!! WHY NOT JUST HAVE THE AMP SET THIS WAY??? YOU CAN ALWAYS TURN DOWN THE BASS???!!!
7. The "crunch" channel has the correct amount of low end. The lead channel does not have enough... You can always turn the bass down..
8. I use an Alesis picoverb in the loop set to spring reverb. This is the Scorpions, Accept, Gary Moore, Judas Priest, etc etc verb sound...
9. I use the Sheffield in slants and add two V30s with Sheffields crisscrossed to the bottoms.
Mods I would like to pursue:
1. Either eliminate the presence or change the sweep point.
2. I really just want the lead channel to have EXACTLY the same bass as the crunch channel. Not the other way around.
3. Hard wire in a 8-10 band EQ into the effects loop.
My amps have gotten pretty stellar reviews so far. I had to close my retail store but we were an authorized service center for all the major brands and I had access to all the schematics.
My typical mod package for a 5150 is:
1. Add adjustable bias.
2. Use matched output tubes. I prefer Ruby's and TADs even though I have yet to try very many Russian output tubes (we are a dealer for Ruby and TAD).
3. Tone stack the 12ax7s to (from V1 to the end): EHX, Mullard, Mullard, EHX, JJ or MUllard.
4. Add 10 pf cap to remove hiss
5. R9: piggyback a resistor on top of the 1 meg resistor. I have a peg board and I use clips to find the resistor that gives me the right amount of saturation reduction). I have a board that goes from about 100k to 250K. I use as little reduction as possible. This is one of the main mods to reduce hiss also.
6. 40H Hammond choke- this mod does nothing a room volumes (really) but with two to four 4x12's and the amp set to 8 ohms and loud it is a massive improvement!!!
I also run a 10 band EQ in the loop. THIS SHOULD BE IN THE CIRCUIT!!!! This amp is 50% better with an EQ in the loop... Eq' ing the power amp side of ANY amp is an improvement... I am looking at a way to mount the eq in the amp....
Here is what I found...
First off. If you want to sound like a Boogie, buy a Boogie... I recommend the Triple Rec... The 5150 is a modded Marshall, and the more you jack with the thing the more you realize that... I can add one resistor and nail the "Heading Out to Highway" JMP tone exactly. You can hear the basic tone signature. The Soldano is a modded Marshall also, same as the 5150. The Boogie is different and does not sound like a Marshall to me at all...
1. I do not use the "presence". It is set on zero. There is nothing good coming from this knob. Most of the "fizz" or "brittleness" in this amp comes from the presence. It appears to be a "resonance" for a treble notch that makes the amp sound like crap. If you really bear down and try to capture all the great tones from modded Marshalls in the past, this knob RUINS IT!!!
2. Bottom cabs have way more bottom end than slants, and sound "correct" to my ears... IF YOU PLAY DROP TUNING GET A SLANT!!!
3. Slants has more projection than bottoms, and do not get boomy like bottoms. See #2.
4. People use way too much f@@kin gain... They keep looking for "clarity" while using 14 layers of gain... The EQ in the loop with improve the gain better than more gain... It makes the amp come alive.
5. For reals.... A tube 100 watt amp does not sound worth a shit on one 4x12. The speakers are really overloaded. A 4x12 alone is really best suited to 50 watts or less... I use two and EVH used 4... The 5150 really starts changing character when the speaker load is upped after the bias is set correctly.
6. Once the EQ is the loop the lead channel can get a bassy as you want... JUST BRUTAL!!! WHY NOT JUST HAVE THE AMP SET THIS WAY??? YOU CAN ALWAYS TURN DOWN THE BASS???!!!
7. The "crunch" channel has the correct amount of low end. The lead channel does not have enough... You can always turn the bass down..
8. I use an Alesis picoverb in the loop set to spring reverb. This is the Scorpions, Accept, Gary Moore, Judas Priest, etc etc verb sound...
9. I use the Sheffield in slants and add two V30s with Sheffields crisscrossed to the bottoms.
Mods I would like to pursue:
1. Either eliminate the presence or change the sweep point.
2. I really just want the lead channel to have EXACTLY the same bass as the crunch channel. Not the other way around.
3. Hard wire in a 8-10 band EQ into the effects loop.