S.I.R. 100W SuperLead Schematic pt. II

[dukeamps]

what cap from .47uf to .68uf? changing c4 and c10 what is the difference?

Its the cap over the 820r stage, it will give you a bit more bass or low mids, also if you leave the 34 mod the way it is, & change the 150k on the gain pot to 220k or 330k, that will give you a little bit more tone. Just try one thing at a time, & if you don't like the change put it back to stock 34 & start over.

[giordydiver]

ok try in this way... I thing c4 from 2n2 to 500p make also sound bigger with less treble. is this wrong?

[rockgod212]

here's what's in my amp at the moment......

1st stage
47k input (I might go back to 33k)
2.7k/.68
220p over plate
470k/2n2 peaker
220p on gain 1- 150k wiper to ground on switch from socket

2nd
10k/.1
470k/470p 2nd treble peaker (not sure if this is causing the thin lead tones or not?)
gain 2 with a 470k wiper to ground on a switch from socket

3rd
8.2k/.22
2n2 over plate (I think I might need to lower this cap a bit)
4.7m to ground from coupler (this probably can be removed now, not even sure why I did this anymore)
470k/470k/470p

4th
820r ( I have a .47u orange drop coming, so that will go on an existing switch for #34 mode)

**all 22n couplers
**.1/.56u presence
**100k@4ohm NFB
**TS 250p/33k
**still using 10k tail, as im reluctant to change it
**NOS china's
** tunqsol 6550's biased to 45mA or so ( I like them a bit hot)


the amp sounds pretty good, although when I played it with the band using the g12-80's I kept experiencing really thin, sorta compressed bass sounding lead tones, I suspect a non true bypass pedal (mxr 10 band eq) on my board is causing signal loading/ tone color type stuff, or it could be my A5 JP humbucker loaded les paul, as it sounds pretty good with the A2 loaded les paul. I will do some more play testing on sunday with the band, then tweak it some more. going to roll some tubes too, as im getting a lot of ground noise- my amp is normally really quiet, so I suspect a V1 change is needed soon.

[bennyx]

now is perfect.....680n on presence and EI preamp tube V2
.....setting all at 5....gain 8-9......gain2 10
https://www.youtube.com/watch?v=8PBbVDuufTs

[CoffeeTones]

May I suggest a 100k resistor after the master volume, 100k to 120K NFB at 8 ohm tap, 1k5 to 22k grid stopper before stage 2, 22k to 100k grid stopper before stage 3 and 1000pF in place of 2200pF bypassing the 470k (with .68uF presence).

[giordydiver]

so change c4 to 500p, c8 to 2.2n, c10 to 250p and remore brighcap? the other mods as #34?
I have seen a video about bringcap value and I could hear that it change also the amount of gain

If you like the 34 but just want it to sound a bit bigger, then put it back to the 34 mod & try this, change the ,47u to .68u, if thats not enough then, change the .1u over the 10k to .22u or .47u, also try .68u on the pres, & maybe change the tail resistor to 10k, hope this helps

To have a darker sound and cut treble what can I do?

[dukeamps]

so change c4 to 500p, c8 to 2.2n, c10 to 250p and remore brighcap? the other mods as #34?
I have seen a video about bringcap value and I could hear that it change also the amount of gain

If you like the 34 but just want it to sound a bit bigger, then put it back to the 34 mod & try this, change the ,47u to .68u, if thats not enough then, change the .1u over the 10k to .22u or .47u, also try .68u on the pres, & maybe change the tail resistor to 10k, hope this helps

To have a darker sound and cut treble what can I do?

From the middle lug of the gain pot, put a 1n to ground, if thats too much try 500p.

[rockgod212]

so 2 to 3 xtra parts plus the tube circuitry could= 150k, 470k/470p xtra treble peaker with that set up the amp is very very bright sounding, I wonder if the 36 had the 56k/250p TS........when I open my amp next I will try the 56k slope and see if that tames the highs better.

[dukeamps]

so 2 to 3 xtra parts plus the tube circuitry could= 150k, 470k/470p xtra treble peaker with that set up the amp is very very bright sounding, I wonder if the 36 had the 56k/250p TS........when I open my amp next I will try the 56k slope and see if that tames the highs better.

Do you use the hot shield ?

[rockgod212]

no I didn't do that yet, whats the 33p cap trick again? I would rather do that I think. I still have some tweaking to do.

when switching cathode caps, which is the better way to stitch them from ground or the anode? Im wondering if my ground noise issue is from switching them from ground, all the long ground wires to front loaded switches could be picking up noise I guess. I may not have shielded them properly either.

[dukeamps]

no I didn't do that yet, whats the 33p cap trick again? I would rather do that I think. I still have some tweaking to do.

when switching cathode caps, which is the better way to stitch them from ground or the anode? Im wondering if my ground noise issue is from switching them from ground, all the long ground wires to front loaded switches could be picking up noise I guess. I may not have shielded them properly either.

you defo need some sort of hot shield to tame the highs and amp noise, you can try a 1n to ground just after the first 22n coupler

[RagnarMarGunn]

Here is a NT clip from the 1993 Marshall slp 100w amp,

http://soundclick.com/share.cfm?id=13231586

I have also added the scom here again because i have done a new clip with a eq change,

http://soundclick.com/share.cfm?id=13230928

Cheers

Damn that's a good sounding amp Nigel

[rockgod212]

ok I will give that a try.

no I didn't do that yet, whats the 33p cap trick again? I would rather do that I think. I still have some tweaking to do.

when switching cathode caps, which is the better way to stitch them from ground or the anode? Im wondering if my ground noise issue is from switching them from ground, all the long ground wires to front loaded switches could be picking up noise I guess. I may not have shielded them properly either.

you defo need some sort of hot shield to tame the highs and amp noise, you can try a 1n to ground just after the first 22n coupler

[herbvis]

ok I will give that a try.

no I didn't do that yet, whats the 33p cap trick again? I would rather do that I think. I still have some tweaking to do.

when switching cathode caps, which is the better way to stitch them from ground or the anode? Im wondering if my ground noise issue is from switching them from ground, all the long ground wires to front loaded switches could be picking up noise I guess. I may not have shielded them properly either.

you defo need some sort of hot shield to tame the highs and amp noise, you can try a 1n to ground just after the first 22n coupler

Does that method affect tone at all?

[rockgod212]

actually the added 470k on gain 2 with the xtra treble peaker sounds really good, the 470k brings things down a bit more, no unstable highs, still retains the crunchy sound. im running 2 tone sucking non true bypass mxr pedals in front of the amp, so I think its the pedals, time to get another pedal looper to run my dirt pedals in......im gonna just plug a wah straight in the amp next time with band and see how it sounds then.