String noise/squeek

[Robert Kesh]

The guitar amp I'm making seems to amplify string sliding noise more than is usual. Does anyone know what frequency this typically occurs at, so I can filter it?

[Bone]

Add a treble cut control or get some flatwound strings The frequency will vary depending how closely the strings are wound and how fast you move your fingers!

[Robert Kesh]

I guess, but it seems to have particular spike to it, like sibilance.

And yes, I'm going to roll off the highs, but I'd like some idea of where I should aim for.

[tinitus]

Originally Posted by Robert Kesh

The guitar amp I'm making seems to amplify string sliding noise more than is usual.

why

[Robert Kesh]

Originally Posted by tinitus

why

Perhaps because the tone stack hasn't been put in? Other than that, not sure yet. My first build of an amp, and kind of my own design, in that it's cobbled together from bits and pieces and ideas from elsewhere.

Two 6N11s and an LM3875.

It probably just needs a treble roll off as has been said. At the moment it has nothing rolling off the high end except grid stoppers.

[tinitus]

could it be the opposite, and that you have less than usual low end amplifying
so when you cranck it up your top gets too hot

don't know, but maybe its just a matter of wrong input resistors, or some other simple thing

[JMFahey]

String noise/squeek
The guitar amp I'm making seems to amplify string sliding noise more than is usual. Does anyone know what frequency this typically occurs at, so I can filter it?

Short answer, don't.
You will kill sparkle, brightness, definition.
Improve your chording and firger technique and you won't have problems.
Just curious: what speakers are you using?
Is it the one you showed lying on the table, without a proper cabinet?
If so, correct that first, you are killing mid and bass big time, so only treble is left.

[Robert Kesh]

Originally Posted by JMFahey

Short answer, don't.
You will kill sparkle, brightness, definition.
Improve your chording and firger technique and you won't have problems.
Just curious: what speakers are you using?
Is it the one you showed lying on the table, without a proper cabinet?
If so, correct that first, you are killing mid and bass big time, so only treble is left.

It's a Marshall Goldback. Yes, that one on the desk, though it's back in its cab now, and still squeaky, though less so. I've been playing guitar for maybe 30 yrs, so I don't think it is particularly technique, as my technique hasn't caused a problem on other set ups.

But yes, not enough mid and bass may be the issue.

Originally Posted by tinitus

could it be the opposite, and that you have less than usual low end amplifying
so when you crank it up your top gets too hot

As was said here too.

Thanks guys, am going to have a tweak.

[cyclecamper]

High gain can make handling noise as loud as playing.

[phase_accurate]

I tend to the same answers as tinitus:

Did you make a coarse check of frequency response ? Maybe some coupling C is too small or something else is giving you a insufficient low-end response.

As already mentioned the frequency response of guitar pickups is very load dependant. Electrically (i.e. without looking at things like PU position, pole size, single-coil or humbucker etc) they usually form a second order lowpass with a peak before the final drop. Your amp might be unluckily loading the PU(s) in such a way that you end up with the peak in an unpleasant frequency range.

Regards

Charles