Amp modders... How do I smooth out the 1-wire mod?

[Vrad]

Hey Jerry,

I tried what I think you were saying.
V1A 2.7k/.22uf (didn't have a .1uf)
V1B 2.7k/.47uf

I left the 810/.68uf on the V2A for now and didn't touch the 470k resistors yet.

It sounds alot better. Less splattery and messy. Sounds really good with my OD808 as a boost.

22u, 2.2u or .22u (220n)?

I'd go with 1u and then you can leak some treble to the ground after the first stage with a small cap (between 100p and 560p)
it's a very common trick to keep amps smooth and middy
you'll find this in a lot of famous amps
a small high voltage cap linking the plate pins of the phase inverter is useful too (regular value is 47pf, but you can only notice some difference above 120p)

You mean .1uf?

He means 1uF and I believe that is what Jerry meant as well...

Steve

So on the V1A, you're saying 2.7k/1uf?

Yes, correct. You could also try a 1.5K/4.7uF V1A and up the grid resistor to 150K

Steve

Thanks Steve, I'll give it a shot. The lower values on the V1A/V1B seem to be headed in the right direction. It cleaned up the sound alot.

 

[Anonymous]

Hey Jerry,

I tried what I think you were saying.
V1A 2.7k/.22uf (didn't have a .1uf)
V1B 2.7k/.47uf

I left the 810/.68uf on the V2A for now and didn't touch the 470k resistors yet.

It sounds alot better. Less splattery and messy. Sounds really good with my OD808 as a boost.

22u, 2.2u or .22u (220n)?

I'd go with 1u and then you can leak some treble to the ground after the first stage with a small cap (between 100p and 560p)
it's a very common trick to keep amps smooth and middy
you'll find this in a lot of famous amps
a small high voltage cap linking the plate pins of the phase inverter is useful too (regular value is 47pf, but you can only notice some difference above 120p)

You mean .1uf?

He means 1uF and I believe that is what Jerry meant as well...

Steve

So on the V1A, you're saying 2.7k/1uf?

Yes, correct. You could also try a 1.5K/4.7uF V1A and up the grid resistor to 150K

Steve

Thanks Steve, I'll give it a shot. The lower values on the V1A/V1B seem to be headed in the right direction. It cleaned up the sound alot.

Steve

 

[Vrad]

Steve

Quick noodling clip with the current configuration.
Straight to the amp. There's more gain on tap, but its not quite controllable yet.

Oh yeah, no boosts, just guitar-> amp -> cab miked up with 1 SM57

 

[duesentrieb]

Hi Vlad, the key is to lower the signal, to clean it up.
Use a 250k Log Gain Pot (if you just have a 1M, solder in and wiper together and a 220k from it (in/out/220k) to ground.
Also install a grid-R (220k) in front of the CF-input stage and on its cathode use a 1k and no bypass cap.

HTH

Olaf

 

[duesentrieb]

. . . it also helps to increase the voltages in the preamp by lowering the resistors in the B+ (10ks --> 1k).

All those cathode bypass caps just increase mud and mids. If you loose too much gain by getting rid of them, lower the value of the cathode resistor instead (w/out cap). From 2k7 --> 1k.

 

[ericsabbath]

Yes, correct. You could also try a 1.5K/4.7uF V1A and up the grid resistor to 150K

Steve

egnater seminar?

 

[Anonymous]

Yes, correct. You could also try a 1.5K/4.7uF V1A and up the grid resistor to 150K

Steve

egnater seminar?

Hey - it sounds good! Very smooth gain...

Steve

 

[Vrad]

. . . it also helps to increase the voltages in the preamp by lowering the resistors in the B+ (10ks --> 1k).

All those cathode bypass caps just increase mud and mids. If you loose too much gain by getting rid of them, lower the value of the cathode resistor instead (w/out cap). From 2k7 --> 1k.

Thanks Olaf!

 

[Vrad]

Yes, correct. You could also try a 1.5K/4.7uF V1A and up the grid resistor to 150K

Steve

egnater seminar?

Hey - it sounds good! Very smooth gain...

Steve

Steve you're referring to the 100K plate resistors?

 

[Anonymous]

Hey Jerry,

I tried what I think you were saying.
V1A 2.7k/.22uf (didn't have a .1uf)
V1B 2.7k/.47uf

I left the 810/.68uf on the V2A for now and didn't touch the 470k resistors yet.

It sounds alot better. Less splattery and messy. Sounds really good with my OD808 as a boost.

22u, 2.2u or .22u (220n)?

I'd go with 1u and then you can leak some treble to the ground after the first stage with a small cap (between 100p and 560p)
it's a very common trick to keep amps smooth and middy
you'll find this in a lot of famous amps
a small high voltage cap linking the plate pins of the phase inverter is useful too (regular value is 47pf, but you can only notice some difference above 120p)

You mean .1uf?

He means 1uF and I believe that is what Jerry meant as well...

Steve

So on the V1A, you're saying 2.7k/1uf?

Yes, correct. You could also try a 1.5K/4.7uF V1A and up the grid resistor to 150K

Steve

I meant (of course) up the plate resistor to 150K...

Steve

 

[jerrydyer]

that clip sounded pretty mean I like it. I like a blend between marshall and vox. I have this one circuit thats sounds like a really pissed off vox. its a 4 gain stager though. But actually I was talking .1 not 1 depending on where you put the 1uf to mme (just my opinion) it had too much low end. it was like working against me.

 

[Anonymous]

that clip sounded pretty mean I like it. I like a blend between marshall and vox. I have this one circuit thats sounds like a really pissed off vox. its a 4 gain stager though. But actually I was talking .1 not 1 depending on where you put the 1uf to mme (just my opinion) it had too much low end. it was like working against me.

2.7K/.1uF on V1A?

Steve

 

[Anonymous]

Yes, correct. You could also try a 1.5K/4.7uF V1A and up the grid resistor to 150K

Steve

egnater seminar?

Hey - it sounds good! Very smooth gain...

Steve

Steve you're referring to the 100K plate resistors?

Yeah, sorry - V1A plate resistor. Leave V1B at 100K...

Steve

 

[Vrad]

that clip sounded pretty mean I like it. I like a blend between marshall and vox. I have this one circuit thats sounds like a really pissed off vox. its a 4 gain stager though. But actually I was talking .1 not 1 depending on where you put the 1uf to mme (just my opinion) it had too much low end. it was like working against me.

Thanks Jerry, its really getting there.
I'll mess with those components some more and find a combo that's perfect. I don't want the amp too thick because then it loses percussivness.

 

[Vrad]

Yes, correct. You could also try a 1.5K/4.7uF V1A and up the grid resistor to 150K

Steve

egnater seminar?

Hey - it sounds good! Very smooth gain...

Steve

Steve you're referring to the 100K plate resistors?

Yeah, sorry - V1A plate resistor. Leave V1B at 100K...

Steve

I see and that changes the bias on the tube?

 

[Chubtone]

Thanks Jerry, its really getting there.

"It's getting there". LOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOL OLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOL



Come on now Vlad!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! You've been to Metro Amp forum enough times to know it's never THERE!!!!!!!!!!!!!!!!!! Never! It's always just one more tweak, one more thing, just one more thing. Rockstah and Ralle record the most sick sounding clips ever. I'm talking probably better than Eddie's amp actually sounded in the studio dry and 20 minutes later they're ripping into it again, because it's almost there.

 

[Vrad]

Thanks Jerry, its really getting there.

"It's getting there". LOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOL OLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOLOL



Come on now Vlad!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! You've been to Metro Amp forum enough times to know it's never THERE!!!!!!!!!!!!!!!!!! Never! It's always just one more tweak, one more thing, just one more thing. Rockstah and Ralle record the most sick sounding clips ever. I'm talking probably better than Eddie's amp actually sounded in the studio dry and 20 minutes later they're ripping into it again, because it's almost there.

I'm trying to not go down that road man! No really I am! LOL!
I know you don't believe me... LOL!

 

[Anonymous]

Yes, correct. You could also try a 1.5K/4.7uF V1A and up the grid resistor to 150K

Steve

egnater seminar?

Hey - it sounds good! Very smooth gain...

Steve

Steve you're referring to the 100K plate resistors?

Yeah, sorry - V1A plate resistor. Leave V1B at 100K...

Steve

I see and that changes the bias on the tube?

It is changing the gain of that stage. A higher value will increase the plate voltage drops/rises (depending on the polarity of the input signal). V=IxR, right? After the coupling cap (which blocks DC), you have bigger swings in AC voltage with a higher resistance value and thus, you have higher gain.

The cathode R/C is a tuned circuit changing the frequency at which gain is increased and also increases gain.

Steve

 

[Vrad]

Yes, correct. You could also try a 1.5K/4.7uF V1A and up the grid resistor to 150K

Steve

egnater seminar?

Hey - it sounds good! Very smooth gain...

Steve

Steve you're referring to the 100K plate resistors?

Yeah, sorry - V1A plate resistor. Leave V1B at 100K...

Steve

I see and that changes the bias on the tube?

It is changing the gain of that stage. A higher value will increase the plate voltage drops/rises (depending on the polarity of the input signal). V=IxR, right? After the coupling cap (which blocks DC), you have bigger swings in AC voltage with a higher resistance value and thus, you have higher gain.

The cathode R/C is a tuned circuit changing the frequency at which gain is increased and also increases gain.

Steve

I see.... So the R/C is where you set up what freq's get boosted then the coupling caps add gain on top of what's already boosted.

 

[Anonymous]

Yes, correct. You could also try a 1.5K/4.7uF V1A and up the grid resistor to 150K

Steve

egnater seminar?

Hey - it sounds good! Very smooth gain...

Steve

Steve you're referring to the 100K plate resistors?

Yeah, sorry - V1A plate resistor. Leave V1B at 100K...

Steve

I see and that changes the bias on the tube?

It is changing the gain of that stage. A higher value will increase the plate voltage drops/rises (depending on the polarity of the input signal). V=IxR, right? After the coupling cap (which blocks DC), you have bigger swings in AC voltage with a higher resistance value and thus, you have higher gain.

The cathode R/C is a tuned circuit changing the frequency at which gain is increased and also increases gain.

Steve

I see.... So the R/C is where you set up what freq's get boosted then the coupling caps add gain on top of what's already boosted.

No, the cathode R/C adds gain with the cap to ground as well as says what frequencies get added gain (anything above the "rolloff frequency" gets the added gain - you can calculate that frequency like this: F = 1/(2pi)RC, where pi = 3.14xxxxx). The coupling caps don't add gain, they block DC. The plate resistor adds gain and the coupling caps block DC.

See what I'm saying? Both the plate resistor and the cathode cap in a gain stage add gain. You can't just randomly raise the plate resistor value either. You have to adjust the cathode resistor as well to provide the bias to the stage.

Steve