1086 gain mods?

Anyone know an easy way to add a bit more gain to 1086 module? (I'm not talking about a tube change, talking component value changes). I like the tone for the most part, just wish it had a bit more. I know on my Framus Cobra it was a matter of removing a resistor and replacing it with just a piece of wire and changing the value of another resistor. After that it is just a killer sound! Most aggressive I've heard. I'd love to get that tightness from some of the Randall modules. That's one reason I love the 1086. It sounds really tight.

Also which caps are affected by the mid shift switch?

At this point any info. would be great. Just getting started with this. These amps are so cool, you can mess with the preamps and not have to shut the whole amp down. As long as you have more than one module you can keep on playin'while you mess with other stuff. Thanks!

C5 and C14 on the mid switch I believe...

I haven't done a gain mod to the 1086, but the mid-shift caps are right behind the small toggle. C14, C15, I believe.

Cool. I'd like to screw around with values on these 2 just to see. On the bright switch on the other modules, is that just changing the voicing on the treble? Just learning all ofthis stuff so bear with me. Thanks in advance. I will post my changes and results as I go.

The bright switch is a treble bypass capacitor I think...it lets treble past the gain pot to brighten up the amp at low settings. I assume you could change the value to change the effect?

It has no effect when the gain is dimed.

<---- Not an expert

ok. I guess it's a "filter cap". I wonder if there is a way to add a "mid shift" to the other modules. So many questions! Guess I gotta pull out the old tube amp handbook. Whatever I figure out I would be motre than happy to post.

Lotus1 said:

ok. I guess it's a "filter cap". I wonder if there is a way to add a "mid shift" to the other modules. So many questions! Guess I gotta pull out the old tube amp handbook. Whatever I figure out I would be motre than happy to post.

Click to expand...

Some of the newer PCB layouts have the pads in place for the 1086 switch...it's just not installed and the faceplate covers the hole in the carriage.

I will have to look at my other modules and see what I have. I'd love to setr one up with a nice midrange sound and also a really deep mid scoop for that Pantera sound.

Just realized you could probably use one of those push pull type pots so you don't even have to drill a new hole. Things will get pretty interesting.

There is not one person here that can help me squeese a bit more gain out of this module?

Lotus1 said:

There is not one person here that can help me squeese a bit more gain out of this module?

Click to expand...

I deicided to give free simple diy mod advice to all you guys here with soldering iron skills.

Salvation 1086PLUS mod

1.Do not disassemble the module, only take off tube guard and 1st tube.
2.find R16 resistor - it is by side of 1st tube (yellow, violet, red stripe) Leave it on its place!
3. buy metal film, 0,6watt 3k3 resistor
4. solder this resistor in parallel - "piggybacking" to both ends of R16 (be carefull to not overheat the PCB!!) Before soldering cut both ends to be accurately long to solder.
5.Thats all. Take 1st tube back and mount tubeguard.

With added gain the module will be slightly more noisy. This is pretty common thing. I allways say" No gain, no pain".
This modification is at your own risk.
Advantage: you can easy take it back to stock.

Anthony

Thank you for the advice. What is that resistor in the signal chain? The cathode resistor? You must understand. I don't want people who do this stuff for cash to lose money. That is not my intent at all. I just want some simple help to take a stock module that I already like and tweek it ever so slightly to aceive what I'm after. Believe me, if I really want one modified I will send it out. Just so you know where I am coming from. Thank you again.

salvation said:

Lotus1 said:

There is not one person here that can help me squeese a bit more gain out of this module?

Click to expand...

I deicided to give free simple diy mod advice to all you guys here with soldering iron skills.

Salvation 1086PLUS mod

1.Do not disassemble the module, only take off tube guard and 1st tube.
2.find R16 resistor - it is by side of 1st tube (yellow, violet, red stripe) Leave it on its place!
3. buy metal film, 0,6watt 3k3 resistor
4. solder this resistor in parallel - "piggybacking" to both ends of R16 (be carefull to not overheat the PCB!!) Before soldering cut both ends to be accurately long to solder.
5.Thats all. Take 1st tube back and mount tubeguard.

With added gain the module will be slightly more noisy. This is pretty common thing. I allways say" No gain, no pain".
This modification is at your own risk.
Advantage: you can easy take it back to stock.

Anthony

Click to expand...

Thanks Anthony for adding this. For those of you that are fully modding your module. This advice is the same putting a 2k resistor in place of the 4k7 at r16. One thing you might want to do is replace r16 on the board with a dpdt switch and then put a 4k7 on one side and a 2k on the other. Then you could switch between them for stock 1086 or ultra1086

fearnloathing said:

salvation said:

Lotus1 said:

There is not one person here that can help me squeese a bit more gain out of this module?

Click to expand...

I deicided to give free simple diy mod advice to all you guys here with soldering iron skills.

Salvation 1086PLUS mod

1.Do not disassemble the module, only take off tube guard and 1st tube.
2.find R16 resistor - it is by side of 1st tube (yellow, violet, red stripe) Leave it on its place!
3. buy metal film, 0,6watt 3k3 resistor
4. solder this resistor in parallel - "piggybacking" to both ends of R16 (be carefull to not overheat the PCB!!) Before soldering cut both ends to be accurately long to solder.
5.Thats all. Take 1st tube back and mount tubeguard.

With added gain the module will be slightly more noisy. This is pretty common thing. I allways say" No gain, no pain".
This modification is at your own risk.
Advantage: you can easy take it back to stock.

Anthony

Click to expand...

Thanks Anthony for adding this. For those of you that are fully modding your module. This advice is the same putting a 2k resistor in place of the 4k7 at r16. One thing you might want to do is replace r16 on the board with a dpdt switch and then put a 4k7 on one side and a 2k on the other. Then you could switch between them for stock 1086 or ultra1086

Click to expand...

I put here the easiest thing to do on 1086 for more gain.
Without disassembling the module and easy-undo.
If you are not skilled, it is your own risk.
I have seen a lot of destroyed and overheated PCBs, non working modules after "modding", poorly drilled faceplates, totally wrong value components etc...

So I decided to take out mod which is easy and not destructive.

Mod above is the easiest , non destructive and most "user friendly".

Anth?ny SALVATION

P.S.: Obviously there is a lot of different components that can be changed for different results

salvation said:

Lotus1 said:

There is not one person here that can help me squeese a bit more gain out of this module?

Click to expand...

I deicided to give free simple diy mod advice to all you guys here with soldering iron skills.

Salvation 1086PLUS mod

1.Do not disassemble the module, only take off tube guard and 1st tube.
2.find R16 resistor - it is by side of 1st tube (yellow, violet, red stripe) Leave it on its place!
3. buy metal film, 0,6watt 3k3 resistor
4. solder this resistor in parallel - "piggybacking" to both ends of R16 (be carefull to not overheat the PCB!!) Before soldering cut both ends to be accurately long to solder.
5.Thats all. Take 1st tube back and mount tubeguard.

With added gain the module will be slightly more noisy. This is pretty common thing. I allways say" No gain, no pain".
This modification is at your own risk.
Advantage: you can easy take it back to stock.

Anthony

Click to expand...

Would this work with say the r16 resistor of the XTC? Just thought I'd ask ask I'm am going to experiment with a few mods on my XTC over the coming weeks.

deadcat said:

salvation said:

Lotus1 said:

There is not one person here that can help me squeese a bit more gain out of this module?

Click to expand...

I deicided to give free simple diy mod advice to all you guys here with soldering iron skills.

Salvation 1086PLUS mod

1.Do not disassemble the module, only take off tube guard and 1st tube.
2.find R16 resistor - it is by side of 1st tube (yellow, violet, red stripe) Leave it on its place!
3. buy metal film, 0,6watt 3k3 resistor
4. solder this resistor in parallel - "piggybacking" to both ends of R16 (be carefull to not overheat the PCB!!) Before soldering cut both ends to be accurately long to solder.
5.Thats all. Take 1st tube back and mount tubeguard.

With added gain the module will be slightly more noisy. This is pretty common thing. I allways say" No gain, no pain".
This modification is at your own risk.
Advantage: you can easy take it back to stock.

Anthony

Click to expand...

Would this work with say the r16 resistor of the XTC? Just thought I'd ask ask I'm am going to experiment with a few mods on my XTC over the coming weeks.

Click to expand...

I tried it, no.

R16 on my XTC is 120 Ohm, not the 4k7 fearnloathing was talking about so I didn't expect it to work.
Also I used a 1k5 since I had that laying around..
I just wanted to see what would happen..

It did something else though: changed the mids/himids, making them more pronounced and slightly muddyer I thought.. (but I didn't check at volume).
It also seemed to drop a tiny bit in gain but that might be the mids speaking..
That said, if you can find out what R16 on the 1086 does and then locate that resistor on the XTC you should be good to go for experimenting!

I'd advise you to keep an eye on this topic though

Mojo on the xtc r16 is tied into op2 you dont want to change this value it will sound bad like you experienced. If you want to do the same mod we are talking about on an xtc you need to change r9 which is 2k7 stock to a lower value say 1k7 but no lower than 820ohms. The XTC is one of the freak boards that has everything numbered differently.

Thanks, I already thought it wouldn't be correct but still I wanted to try.

I noticed from comparing with other gut shots that the XTC is different, but there are no 1086 shots I could compare to.
Maybe we should set up "the great gutshots topic" where we can have a library of good pics of all the modules' boards.

I will try R9 this evening, might be interesting.
I must say I'm totally not starved for gain on the XTC, I'm just wondering how high it goes and what tonal changes there are with this simple mod.

if you push the gain to high you will get blocking distortion. Basically to increase gain you change the voltage divider between gain stages to not dump as much gain to ground.

a member of the forum have told me that the resistor r17 is the one to remplace to have more gain.
here you talk about the r16... is the r16 only for the 1086 ? r17 for the other modules ?