Tascam 388 crackles

[curtiswyant]

Hi there, I just came into possession of a Tascam 388 with under 40hrs of use. However, there is some nasty crackling, fizzing noise coming from the stereo bus. I can hear it through headphones and the monitor outs which are connected to my speakers. It sounds like an old amp that needs a cap job. I went through and checked all of the buttons/switches/pots and the only ones that have any effect on the sound are the L/R switches that assign an incoming channel to the stereo bus. It has nothing to do with recording/playback from tape...it will make noise regardless. If anyone has any suggestions, please help...I'm thinking it's a really dirty pot or a bad ground/bad power supply. Thanks!

 

[cjacek]

Hi there, I just came into possession of a Tascam 388 with under 40hrs of use. However, there is some nasty crackling, fizzing noise coming from the stereo bus. I can hear it through headphones and the monitor outs which are connected to my speakers. It sounds like an old amp that needs a cap job. I went through and checked all of the buttons/switches/pots and the only ones that have any effect on the sound are the L/R switches that assign an incoming channel to the stereo bus. It has nothing to do with recording/playback from tape...it will make noise regardless. If anyone has any suggestions, please help...I'm thinking it's a really dirty pot or a bad ground/bad power supply. Thanks!

It may be as simple as getting some Deoxit (from Caig Labs) in there, on the connectors. Oxidation is always an issue, especially for a machine which had been unused for ages.

I've had at least a couple of issues with "crackling", "static" noise. Usually happens with gear around that 20 and beyond year mark.

~Daniel

 

[tascam388]

Any progress on this curtiswyant? I picked up one of these units yesterday and am experiencing the exact same issue (infact your description is so dead accurate I almost am starting to believe that you are the guy that sold it to me). Outside of the crackling (which is faint in compairson to the recording but simply knowing that it's there is enough to drive me insane) the recording is phenomenal, it'd be a real shame if I had to return it over such a minor annoyance. I had planned to tear it open and give it a good clean as cjacek suggested, I'll certainly post an updated on how I make out with that.

 

[mikey@thecave]

have you guys demagnatized the heads lately????and is the dbx on???

 

[Nils K]

Demagnetizing is a good thing to do (provided it's done correctly, of course!), but although a magnetized tape head may emit pops and sizzles, it will only do so when tape travels past it for reproduction - apparently not an issue here. It sounds like a cleaning job (connectors, plugs, switches, etc.). If you suspect a faulty power supply to be the culprit (possible, but not very likely), however, you should have it checked by a professional unless you feel really, really comfortable doing it yourself.

regards, Nils

 

[tascam388]

have you guys demagnatized the heads lately????and is the dbx on???

I think Nils K is right, this isn't an issue with a magnetized head (though I do plan to demagnetize, it is a good idea). It doesn't matter what input is selected, it appears to be coming from somewhere in the channel strips (the more channels being monitored the worse the noise is, and I can sometimes get a slight amount of fluctuation in noise when moving components). DBX, on or off, has no effect on the noise.

If you suspect a faulty power supply to be the culprit (possible, but not very likely), however, you should have it checked by a professional unless you feel really, really comfortable doing it yourself.

Checking the power supply is a good idea, I will do that while I'm in there. I do have a relative amount of experience with this sort of thing (I used to work for a fire restoration company cleaning fire damaged electronics; who would of ever imagined that you can wash a computer monitor in a sink.... just make it's discharged first ). I was very impressed with the manual (and is obviously very important seeing as I got 3 copies with it), it has incredibly detailed schematics and chassis diagrams (it's always good to know when a spring is going to shoot out at you, or better yet, where the spring that does shoot out at you belongs). They certainly don't make them like they used to.

I've realized that the noise really isn't as bad as I originally thought. It's noticeable when you have everything cranked to the max, but it is virtually inaudible at normal playback volume. I've decided to keep the unit regardless of this issue, if it's not something I am able to fix I'm sure I will be able to find someone who can. Besides, I'd have to change my nick or look like a fool.

 

[curtiswyant]

Well, here's an update.
I went through ALL of the knobs, switches, dials, plugs, faders, etc and they were really scratchy. I wiggled them until it stopped and that seemed to help. A funny thing is that even when the 388 is off, and unplugged from the wall, I can hear this occasional crackle through my speakers. Therefore, I think it's just a minor issue in my house or because I have so much equipment in one room! Since it has no effect on the recording, I'll just ignore it...I did demag, clean the heads, etc and the machine works great.

 

[cjacek]

Well, here's an update.
I went through ALL of the knobs, switches, dials, plugs, faders, etc and they were really scratchy. I wiggled them until it stopped and that seemed to help. A funny thing is that even when the 388 is off, and unplugged from the wall, I can hear this occasional crackle through my speakers. Therefore, I think it's just a minor issue in my house or because I have so much equipment in one room! Since it has no effect on the recording, I'll just ignore it...I did demag, clean the heads, etc and the machine works great.

It's clearly an "oxidation" issue as I said before. May not affect the recording but conductivity may be less than ideal. I still say use some deoxit.

Good luck,

Daniel

 

[Nils K]

curtiswyant, it may in fact be a power cabling issue, in which case you need a visit from your neighborhood electrician... - Do you have any refrigerators, freezers, room heaters or stoves connected to the same mains outlet? Occasionally, the shunt condensers on the pumps of these things may wear, making the motor coils draw large surge currents when shunted in or out, resulting in 'plops', noise or scratching on the mains line. Surge suppressors do exist, but they are expensive. It may be better/more effective to target the problem at its source. I suggest you get a qualified electrician to look over the cablings of your house - it might even save you a couple of bucks on your power bill.

regards, Nils