Integrated SET potentiometer/preamp mod?

[Opti-cal]

Hi guys, I'm hoping someone can advise me as to the feasibility or indeed the likely benefit (if any) of the proposed modification.

Basically solder a 50k resistor (same as volume pot) in its place circled in red.

(See circuit attached)

Apologies I cannot find a schematic.

This will serve two functions potentially.

I can use a passive preamp to add a few more inputs plus I can have a higher quality potentiometer in the chain.

Now there a couple of problems that I can foresee.

Firstly, as the preamp section is still in the circuit, I'm not sure if it is expecting to see full signal from the input before or after the volume pot (I'm assuming after in which case this shouldn't be a problem).

Also do I need to put a ground tapped on to the new part of the circuit as I believe there is one going to the current volume pot?

As you can tell I'm not very technically advanced in modifying my hifi but as these amps are cheap and actually sound pretty good I thought I could "have a go" so to speak.

I shall be in no way offended if someone points out that "this is a stupid idea and you should just leave the thing alone until you learn what you are doing" or similar. Its probably the best thing for me, the cold hard truth!

Or if anyone else has any ideas for improving this amp I'm all ears!

Thanks a lot.

Opti-cal

[Firebottle]

Shouldn't be a problem, or you could just teurn the volume to max and use an external passive/preamp.

If you did replace the pot I would fit a 100K resistor to reduce the loading on any external passive pot.

[Opti-cal]

Thanks Firebottle,

I know its unlikely to make much of a difference in reality but it "should" be better in my head as it cuts out an unnecessary part in the circuit if I'm using an external passive pre.

I've tried the vol at max with a pretty basic passive pre and there wasn't really an audible loss of quality although I didn't really test it for long enough to draw any definitive conclusion.

The placebo effect along with the satisfaction of modding ones own kit should be enough to keep me happy anyway!

As I will be using it with a passive pre (as I need the extra inputs) I think I'll give it a go.

I've actually just this afternoon taken delivery of the "upgraded" version of exactly the same amp so I think I'll have a play with the old one.

New one has some slightly better quality parts floating around. Better caps with some silver wire involved. Will probably sound the same but looks nice.

Like I say they're only cheap so not exactly the end of the world if no real improvement.

Cheers

[Opti-cal]

Here is the "upgraded" version of the same amp.