Topic: Hum from speakers due to home DAT

[goose]

I have a strange problem when I attach a Panasonic home DAT (3800 and 3700 both), analog out via XLR to RCA in on my Rotel RA-985BX integrated amp.  I have used different cables and tried switching power plug outlets for each. 

The hum is not on DAT playback, but is actually only noticeable when I have the selector on the amp to play my cable box for TV sound.  The hum is very pronounced.  When I disconnect the 3700's output cables, the hum goes away.  The hum occurs if the 3700 is on or off, doesn't matter.

Can anyone provide some insight in what is causing the issue or how I can alleviate the problem?

Thanks in advance.

[Tim]

what kind of plug does that 3700 have? you might try one of those adapters that accepts a 3 prong plug and outputs on a 2 prong....

I'd start with that....

[goose]

Thanks for the simple fix - works great with the adapter.  The 3700/3800 have a removeable power plug that terminates in 3 prong.   T is for Timmay.

[bhtoque]

Don't know the cause of your problem, but I have the same sort of issue with my stereo as soon as any of my video components are connected. I've been thinking it is a ground loop with the cable tv/internet line.

Try disconnecting the cable from your tv.

JAson

[goose]

Luckily the adapter worked, as getting to the cable on the TV is tough with the ertertainment unit it is in.  Thanks for the suggestion J.

[Genghis Cougar Mellen Khan]

what kind of plug does that 3700 have? you might try one of those adapters that accepts a 3 prong plug and outputs on a 2 prong....

I'd start with that....

What does this do, eliminate a possible ground loop problem?

[Tim]

what kind of plug does that 3700 have? you might try one of those adapters that accepts a 3 prong plug and outputs on a 2 prong....

I'd start with that....

What does this do, eliminate a possible ground loop problem?

yep

simple and cheap trick I learned from my FOH daze errrrrr days

[Genghis Cougar Mellen Khan]

what kind of plug does that 3700 have? you might try one of those adapters that accepts a 3 prong plug and outputs on a 2 prong....

I'd start with that....

What does this do, eliminate a possible ground loop problem?

yep

simple and cheap trick I learned from my FOH daze errrrrr days

+t, learn something new every day...

I'm not sure if it has to do with the current cycle or what, but in doing car stereo installs DC ground looping was a huge PITA, I wasn't aware that it could be an issue with AC as well.

[bhtoque]

Hey Tim,

Is it ok for the gear to run it ungrounded?

I might try to isolate the cause of my problem, but it seems tempting to just stick one of those between the power strip and the socket.

JAson

[Genghis Cougar Mellen Khan]

Hey Tim,

Is it ok for the gear to run it ungrounded?

I might try to isolate the cause of my problem, but it seems tempting to just stick one of those between the power strip and the socket.

JAson

For the safety of your gear make sure your power strip is grounded.  I'd highly suggest against leaving your power strip ungrounded, without the ground it no longer serves as a circuit protector, it's your last line of defence.

[bluegrass_brad]

The adaptor is a ground lift, and works just like the switch you find on some audio gear (DI boxes, etc)  Like Tim said, I too always have a few of these with me when doing FOH work. Great tool for places that dont have a conditioner and have dirty power.

[bhtoque]

Hey Tim,

Is it ok for the gear to run it ungrounded?

I might try to isolate the cause of my problem, but it seems tempting to just stick one of those between the power strip and the socket.

JAson

For the safety of your gear make sure your power strip is grounded.  I'd highly suggest against leaving your power strip ungrounded, without the ground it no longer serves as a circuit protector, it's your last line of defence.

I knew that would be the case. I'll just have to try one plug at a time and see if I can isolate the problem.

It's been so long since I had the tv/vcr hooked up to the audio stuff because of the freaking hum.

JAson