Noise issues

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finotti
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Noise issues

Post by finotti »

I am having some weird noise issues recording the guitar. There is a reasonable amount of gain, so noise is to be expected. But what is weird for me (and I am not sure if this is actually usual) is that the noise goes away when I play a note. It is not that the sound of the note covers the noise, the noise actually goes away with the note and comes back when the note starts to die.

Here is a clip of that: https://web.math.utk.edu/~finotti/misc/GTRtest_r1.flac

This is a strat. The first note is in position 2 (hum cancelling) and the second is in position 1 (single coil). You can hear me flipping positions.

I've tried with two guitars (this Surh strat and a PRS with humbuckers) and I tried to swapping cables. (Although, I made both, so maybe I've botched both...) In the clip I am using Guitarix's Tube Screamer, tamgamp, LSP impulse response loader (with an Own Hammer IR), Ardour's ACE Delay, and Dragon Fly Reverb, but I tried with other amp sims and effects (Mercuriall AmpBox and Amplitube 5) with the same result.

Any ideas of what can cause that problem?
merlyn
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Re: Noise issues

Post by merlyn »

It sounds like compression. The noise hasn't actually gone -- it's been pushed down in level by the signal. There could be a compressor somewhere in the chain, or it could be down to the distortion. Valve distortion introduces compression and so would a digital model of it.

Have you tracked down where the noise is coming from? There's the guitar, the preamp in your interface, and the settings on the amp simulators. Tweaking these levels may reduce the noise, but noise is going to be part of a sound that uses a lot of gain.
asbak
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Re: Noise issues

Post by asbak »

Add a noise gate to your signal chain.
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finotti
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Re: Noise issues

Post by finotti »

Thanks for the replies!
asbak wrote: Sat Jan 22, 2022 5:09 pm Add a noise gate to your signal chain.
I have one but disabled to find out what is happening...
merlyn wrote: Sat Jan 22, 2022 3:48 pm It sounds like compression. The noise hasn't actually gone -- it's been pushed down in level by the signal. There could be a compressor somewhere in the chain, or it could be down to the distortion. Valve distortion introduces compression and so would a digital model of it.
I guess that makes sense. I do not have any compressor in the chain, but of course, an amp simulation with that much gain will compress the sound.

Maybe I just don't remember anymore, but I didn't think that happened with a real amplifier. The noise would just stay there and the guitar sound would just cover it when playing.
merlyn wrote: Sat Jan 22, 2022 3:48 pm Have you tracked down where the noise is coming from? There's the guitar, the preamp in your interface, and the settings on the amp simulators. Tweaking these levels may reduce the noise, but noise is going to be part of a sound that uses a lot of gain.
I am having a hard time finding the problem. I expect noise, due to the gain, but that seems excessive. I tried different guitars and cables (although I need to test more cables, maybe) and amp simulations. I guess next I will try a long cable and get away from the computer to see if it helps... Maybe try a DI instead of going direct to the interface.

Thanks again!
finotti
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Re: Noise issues

Post by finotti »

So, I tested a long cable and away from the computer, and I still had a lot of noise...

So, I got my (passive) DI box to try, and the noise was down to expected levels!

But: when I tried again plugging in directly to the interface (Focusrite 2i2 gen 2), the noise was down too! It was connected at the same input, with exactly the same settings as before.

So, I still don't know what is/was going on... Maybe plugging and unplugging a few times cleaned the connection? Gremilins?

Anyway, thanks for your input!
j_e_f_f_g
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Re: Noise issues

Post by j_e_f_f_g »

Maybe a grounding issue. When your fingers touch the strings, that changes the grounding path. Also, moving away from something that could be causing your pickup to generate noise may be responsible for the noise difference.

Replacing your passive pickup with an active one may help.

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asbak
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Re: Noise issues

Post by asbak »

I have a cheap active DI & Amp Sim pedal, thank you goes to Mr Uli. Guitar goes in there and then through to the sound card & tramp's Guitarix. There is no noise. Well, not until I try to play anyway. :mrgreen:

However, I did notice that with some cables of rubbish quality there'd either be intermittent problems with sound dropping out or there'd be loads of (unwanted) noise problems.

Clean good quality jack plugs and good quality cable may be your friends in such situations.
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