Suround sound hum

kenbt · 10-23-2006, 05:07 PM

I know there have been discussions about surround sound back ground noise, especially a hum or static....I found out lately that mine
intensified when I exchanged by Sirius Radio Reciever (insatalled by the factory when I purchased it as an option on the coach) with a new receiver. I had an obvious hum in the rear surround speackers. But only when I was plugged into shore power. Shore power off, no hum. I
went back to Circuit City where I bought the new receiver/tuner and they said it must be a speaker ground problem. They told me to add a
grond wire to the speaker plug at the Sirius Receiver. I did that and it reduced the hum 90% but not 100%. I noticed that the regular
Winnebago Radio when in AM or FM mode still had a slight hum with the Sirius Receiver Off also. If I killed the shore power switching
to 12V the hum went away both on Sirius Radio and the regular radio in AM or FM mode. I understand that some people believe its the
inverter, but is that true with the inverter in the off position, also? Has anyone found a fix so far?????

kenbt · 10-23-2006, 05:07 PM

I know there have been discussions about surround sound back ground noise, especially a hum or static....I found out lately that mine
intensified when I exchanged by Sirius Radio Reciever (insatalled by the factory when I purchased it as an option on the coach) with a new receiver. I had an obvious hum in the rear surround speackers. But only when I was plugged into shore power. Shore power off, no hum. I
went back to Circuit City where I bought the new receiver/tuner and they said it must be a speaker ground problem. They told me to add a
grond wire to the speaker plug at the Sirius Receiver. I did that and it reduced the hum 90% but not 100%. I noticed that the regular
Winnebago Radio when in AM or FM mode still had a slight hum with the Sirius Receiver Off also. If I killed the shore power switching
to 12V the hum went away both on Sirius Radio and the regular radio in AM or FM mode. I understand that some people believe its the
inverter, but is that true with the inverter in the off position, also? Has anyone found a fix so far?????

John_Canfield · 10-24-2006, 04:38 AM

Is this the scenario - Inverter/charger off, no hum, inverter/charger on, hum?

Maybe try running a temporary ground from the chassis of the surround sound to the radio to the Sirius - then you could eliminate a ground loop as the problem.

You could also have hum introduced in the speaker wires themselves by induction from some offending device.

DonavonP · 10-25-2006, 12:19 PM

You're not alone with the surround sound hum. I gave up on trying to fix it.

bill jones · 10-25-2006, 01:08 PM

I wish I had a 'scope to put on the DC out of my inverter, bet it dirty. I've been chasing that hum for 2 years off and on.

wagonmaster2 · 10-25-2006, 07:41 PM

My noise in the surround sound speaker system is a tick-tick-tick sound when the speaker switch is set to radio instead of TV and the radio is off. If the switch is set back to TV the noise stops. It took me several trips in the coach to realize this but have never tried to find the culprit. Easier to just live with it.
Wagonmaster2
2004 Meridian 36G

diesellabs · 10-26-2006, 01:33 AM

Had the same tick-tick problems with our 05 Journey. Put it on the list of items to have the Forest City techs look at in Sept. They installed a filter and cured the problem.

Ed Gardiser · 10-26-2006, 01:46 PM

diesellabs
Where did they install the filter ?
Ed Gardiser
Escondido,Ca.
04 Vectra
87 Nissan PickUp
FMCA

Jim · 10-26-2006, 02:28 PM

do a search for the word "amp" author jim for info on similar problems..jim

diesellabs · 10-27-2006, 02:20 AM

Ed,
The filter was installed close to the amplifier in the floor area. Sorry, I'm not at the coach now or I could be more specific and even give the mfr/part no. for the filter...

Ed Gardiser · 10-27-2006, 05:45 PM

Thanks
Ed

FrankieJ · 10-28-2006, 05:02 AM

.... maybe it is too early in the day and the rain and wind have dampened my ability to think... but ... don't you have the assumptions reversed?

Converter takes the 110V shore power and converts it to 12V useage and the inverter takes the 12V power and inverts it to 110V?

So, if that is true... then maybe a "dirty" converter might be the culprit.

Like some of you .. I had a hum in the premi sound system ... TV/Radio switch was the culprit.

Please correct me if I am off base.

bill jones · 10-28-2006, 08:20 AM

FrankieJ,
When I was referring to the "inverter " output being dirty, I was in fact talking about the Dimensions inverter/converter. It's usually thought of as a combi, which means inverter and converter combined. when plugged into shore power I believe the output from the 12VDC converter section it fed through the batteries to all 12VDC systems. I was speculating on the possibility of some 60 Hz getting through to the audio systems. Sorry, in my advanced age my descriptions of things gets fuzzy.

kenbt · 10-28-2006, 12:27 PM

Well the update on the new sirius radio...I will be returning it because I cannot get rid of the excessive hum when plugged into shore power....funny thing is the factory installed unit from Winnebago which is a Kenwood model has no hum...I believe it is the antenna that might be different..I was trying to use the factory install antenna with the new radio but believe even though the sales people say it should not make a difference because all sirius radio's use the same connection..I believe it does.