BajaNomad - Inverter noise on stereo

Inverter noise on stereo

vandy - 12-7-2008 at 09:52 AM

Does anybody know how to eliminate the 60 Hertz buzz from a stereo running on a power inverter?

My buddy is running a 1500 watt inverter from deep cycle batteries to power his huge JBL PRX515 self-powered speakers, and finds the buzz annoying at low volume.

Of course, his neighbors find annoyance at high volume, but that's beside the point.

Thanks for any help

estebanis - 12-7-2008 at 09:56 AM

That is going to be tough! As you may know the circuitry in the inverter chops the DC to create the AC 60 hz. This chopping causes noise. Noise can be one of the worse tasks for a tech to resolve. Maybe he should get a honda Gen and a 250 ft extension cord... :tumble:

capt. mike - 12-7-2008 at 10:44 AM

you need a sine wave inverting generator geared to run sensitive electronics. or an inverter with regulated and filtered output - or so i have been told.
that's why i have a Honda ECU i2000

it safely runs all my audio, video and computers with no hum or errant ground loops.
also check to ensure you DO have adequate grounding on all links in the chain. it sounds like a ground issue if you are leaking 60 hz hum or buzz.

TMW - 12-7-2008 at 10:59 AM

To follow up on what capt. mike said. If your equipment is using a three prong power cord get an adapter to eleminate the groung pin, the round pin on the plug, not the flat ones. If your not using a three prong plug try running a ground wire from the stereo equipment, some have a grounding post, to a good ground like a water pipe. Otherwise you may just have to get a better generator. Another thought is to put a good graphic equalizer between the stereo unit and the amp speakers and roll off the low frequency, say 100Hz and below, end. This won't help if the hum/buzz is originating in the amp speakers which it sounds like it is.

K.I.S.S.

Dave - 12-7-2008 at 11:00 AM

I would first try a ground loop isolator. You can find 'em online for about $12.

landyacht318 - 12-7-2008 at 11:17 AM

Quote:

Originally posted by vandy
Does anybody know how to eliminate the 60 Hertz buzz from a stereo running on a power inverter?

My buddy is running a 1500 watt inverter from deep cycle batteries to power his huge JBL PRX515 self-powered speakers, and finds the buzz annoying at low volume.

Of course, his neighbors find annoyance at high volume, but that's beside the point.

Thanks for any help

A true sine wave inverter will eliminate the buzz but they're pricey.

I've had some success in eliminating such noise by twisting the power leads from the inverter. 12 to 20 times per foot.
Some ferrite rings are supposed to help as well.

I'd post this question on the Arizona wind/sun forum where the members seem to live for questions as yours

http://www.wind-sun.com/ForumVB/forumdisplay.php?f=9&day...
http://www.wind-sun.com/ForumVB/forumdisplay.php?f=9&daysprune=-1&order=desc&sort=lastpost

[Edited on 12-7-2008 by landyacht318]

Russ - 12-7-2008 at 11:43 AM

From my experience here the cheap inverters, usually in the 1500 watt range, are noisy. You can hear fan motors buzz and even a direct run from the batteries that are running the inverters hooked to a 12volt vhf radio can cause a really bad buzz when transmitting. All the previous thoughts are valid too. This was the first thing to pop into my head. I don't know anything about "self-powered speakers" but if they are wireless and near any other wireless device or something with a fan they could very well pick up static from them. Try running the sound system off a generator. If the noise goes away go back and try the inverter with only the sound system plugged in. Or visa versa. I think even some of those "wall warts" , the things you plug in to power dc voltage stuff, may cause noise. There is a long list of stuff that can cause the noise. It's really frustrating to chase the cause down. Good Luck!

BajaNuts - 12-8-2008 at 06:16 PM

Your problems stems from stray electrons leaking out of nicks in the wire insulation-
:lol:

JUST KIDDING!
It seems like we had an interference problem on a cctv system and the solution was the ground loop isolator. I don't remember enough about the specifics of our situation, but the "isolator" sounds familiar....

[Edited on 12-9-2008 by BajaNuts]

Bob and Susan - 12-8-2008 at 06:37 PM

i think its the inverter

there is no "good" 1500 watt inverter

its a modified sine wave and you need a true sinewave

if you "play" you pay :biggrin:

ncampion - 12-9-2008 at 09:47 AM

Might also try a 1:1 isolation transformer, however it's tough to get the noise out of a non-sinewave inverter.

BajaGringo - 12-9-2008 at 09:57 AM

Ditto what Bob said...