[Foosman(5)]

imported post

I had a small pyramid equalizerbooster with 3.75 - 4.0 inchPioneerspeakers. My back speakers are a pair removable6x9 pioneers boxed on top of the trunk lid.

The equalizersucked sinceI could not get the motor ignition whine out . Noise suppression capacitors and verified grounds did not correct the problem.

I just trashed the system and replaced them witholder bose speakers. Some older Corvettes and Cadillacs had small ~4-4.25 inch front speakers. Each speaker had its own amp and the front amps are in the front fairing with the speakers. 6x9 with amp in my box. I did not have to enlarge the existing fairing holes, but I did do some minor internalmods to the dash cover for clearance. Much better sound than before.

But, here is my new problem. With the stock radio, I have a constant low frequency buzz/hisss. Not the high pitch engine ignition rpm whine noise.The constant buzz is a little loud with the amps powered up. I have very little volume control. So, the only way to get rid of the buzz is to turn the radio off or crank up the music. With the radio on and volume low/off, there is no music but a constant buzz. Two/three clicks on the detent volume control and it is already loud. The only way to get rid of the buzz is to give her about two/three more clicksandshe is jammingmasking the buzz.But, it is loud. Sound is maxed out at half - 12 o-clock straight up on the volume control.

The buzz is like a florescent bulb transformer but louder. The buzz is constant and buzz does not get louder with increased volume control. It is just there.

Any ideas on whatcould be done to reducethe buzz/hissss?

 

[GLester]

imported post

Possibly needs a noise suppressor on the fuel pump. That, or a bad ground somewhere. I'm no expert on stereo systems, but these are 2 things that i could think of.:smiler:

Gene:action:

 

[DOC1500]

imported post

Ground , ground , make sure the ground wire is as short as possible to a good ground on the frame. ground wires should also be as isolated from pos wires . the ground wirecan pickup RF from those wires .this was told to me years ago whenI was into car audio.

 

[mclock]

imported post

I don't know if the 15's are the same as the 12's but try switching the wires



around on your speakers and do all of them when you test it. I bought new



speakers for my 1200 and it had a buzz and sounded like crap until I figured



out to try them the other way. It won't hurt anything if it isn't the problem.

 

[machinehead]

imported post

If i understand correctly ... your frnt. spkrs. are the type with there own small amps. and your rear 6 by 9s are not . You are running one amp. for the rears ? Or are you running all spkrs. off the main amp.?
Please clarify as you can not run amplified signal to your already amplified front spkrs. etc. etc.

 

[Big Port Jimmy 6]

imported post

Bose speakers have a different impedance(Ω) value than regular speakers. The GM system speakers did not work with standard head units. The number one complaint when I was a GM tech working on these was a squeal or hum from a speaker.

Jay

 

[Pwhoever]

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Now I know my setup is completely different from yours but I have a Sony CDX-M30 stereo. When that was connected directly to the four speakers, it was fine. However when I added a 4 ch amp, I was getting buzzing from the speakers. And it was only noticeable when the radio was on low volume. If I unplugged the input from the stereo, no buzz. I added ground loop isolators (1 for the front channel and one for the rear) from Radio Shack in between the stereo and the amp and that eliminated the buzzing. On mine it was real easy. I have RCA cords coming from the stereo to the amp and the ground loop isolators also had RCA jacks.

 

[Foosman(5)]

imported post

If i understand correctly ... your frnt. spkrs. are the type with there own small amps. and your rear 6 by 9s are not . You are running one amp. for the rears ? Or are you running all spkrs. off the main amp.? Please clarify as you can not run amplified signal to your already amplified front spkrs. etc. etc.

I am running 4 stock Bose amps that mounts on the speaker. I have them wired to come on with the radio, but they receive power from a relay. They pop when radio is turned on or off. I would like to figure out how I can bleed off the surge/spike.

Bose speakers have a different impedance(Ω) value than regular speakers. The GM system speakers did not work with standard head units. The number one complaint when I was a GM tech working on these was a squeal or hum from a speaker.

True. I believe the impedance is 1 ohm. I believe the lower impedance allows for higher power. I do not see why a different radio or head unit would make a difference for a Boss or low impedance speakers. The radio will put out an audio signal, and the amp will provide the gain to a limit. With the Bose amp circuitry, the amps have to be on (powered) or the speakers will not work.

Not the best set up, but I do like it. What I did figure out, is that I can use the mute to help control the volume. But, it still need work.

 

[tumunga]

Just my two cents on a zombie thread...

I am running 4 stock Bose amps that mounts on the speaker. I have them wired to come on with the radio, but they receive power from a relay. They pop when radio is turned on or off. I would like to figure out how I can bleed off the surge/spike.


True. I believe the impedance is 1 ohm. I believe the lower impedance allows for higher power. I do not see why a different radio or head unit would make a difference for a Boss or low impedance speakers. The radio will put out an audio signal, and the amp will provide the gain to a limit. With the Bose amp circuitry, the amps have to be on (powered) or the speakers will not work.

Not the best set up, but I do like it. What I did figure out, is that I can use the mute to help control the volume. But, it still need work.

If you're running the speaker wires straight from the GL1500 radio to the bose speaker amb, I believe your input signal is too strong for the amp. This could be the sound of the buzzing. You need to get a transformer to lower the output signal from the apm into a line level input for the Bose amplifier. I'm going to use one like this from Pyramid:

http://www.ebay.com/itm/161011278412?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

After that, I"m getting a decent 7 band eq with four channells out, an auxillary input, and a sub out for future use. Gonna hook this all up with a 400 watt 4 channel amp and see how that does me.