Noisy mixing desk

[WarmJetGuitar]

Hey guys!
We're using an old Roland PA-desk for mixdowns - it sounds warm and got a sexy spring reverb.
However it's waaaaay too noisy so guess a cleaning will help solve the problem. Actually I figured what I might have suspected was tape hiss has often been noise from the desk.

Anything particular we should be aware of when cleaning the unit? Guess we need to open it?

Also the gain controls is behaving strangely - sometimes the sound shut off, sometimes it's too distorted without the channel strip clipping. Just old dust? Or is there more to it than that?

 

[briank]

It really depends on what sort of noises you're hearing. If it's just good old fashioned noise floor/hiss, I doubt a cleaning would do a lot. I'd be thinking more about replacing the power supply capacitors.

If your gain controls have a scratchy sound when you turn them, then cleaning may help this. First, before you go taking it apart, just try "exercising" each gain trim pot by turning it up and down through its full range maybe 30 times and see if it clears up. If still crackly/scratchy sounding, and if the pots are not sealed type, as a last resort you can spray a small amount of Caig Fader F5 (formerly called "Cailube MCL" at least in North America) into each pot and exercise as above.

 

[sr71rules]

Cleaning the unit will not clean up the sound, as briank says.

Exercising the pots (rotating them over and over) will help to mitigate the crackle or distortion you hear when moving them and in some cases make them pass audio again if they are really dirty.

To reduce hiss you would need to break out the soldering iron and replace the capacitors, at least on the power supply.

While I don't doubt the board isn't very quiet you may also want to look at your gain staging to see if you can reduce the effects of that noise. Sometimes just sending hotter signals through the board will make a big difference. The board probably won't sound good if you push everything into the red but getting the signals as close to their max as possible will reduce the apparent volume of that underlying hiss.

Robert

 

[Beck]

unfortunately, I would expect a lot of noise from a Roland PA-desk with built-in spring reverb even when brand new. It may be nosier now from other problems like caps, as already mentioned, but these things aren't really designed with recording in mind. Sorry to say.

 

[WarmJetGuitar]

"If your gain controls have a scratchy sound when you turn them, then cleaning may help this."

That's one of the issues.

"To reduce hiss you would need to break out the soldering iron and replace the capacitors, at least on the power supply."

I'll try this - or rather ask a friend to help me out so I don't break the lovely old desk.

"unfortunately, I would expect a lot of noise from a Roland PA-desk with built-in spring reverb even when brand new. It may be nosier now from other problems like caps, as already mentioned, but these things aren't really designed with recording in mind. Sorry to say. "

Yeah, I know that using a live desk for studio ain't exactly kosher - and it is a noisy old beast. Problem is though that we don't have an external spring reverb for the Fostex 450 desk (which is nice and quiet btw) and I've gotten well into the habit of using one desk on the way in, another for listening. It's nice as we can in matter of minutes make a pre-mix to test the general sound without messing with the input levels or bother to write them down. Important as our sessions can be... hazy

I love this forum - so much valuable knowledge. Thanks guys!