Pre-Out Voltage Issue *Vids* HELP

[Kastlez_ 10+ year member]

Alpine 9887

Audiocontrol Overdrive (line driver)

Alpine preouts are 4volts

Audiocontrol goes up to 9volts

Seems like my voltage is extremely low seeing that i only get a 2v reading at volume 23-35 (with the overdrive gains almost maxed out which on my system sounds like it's clipping to hell)

I normally set the audiocontrol to the lowest setting but at that level I get less than 2volts at vol 35/35 on the 9887.

(With gains set properly my normal listening level on the headunit is between 12-16 which means my headunit is putting out less than 1volt.

Is this normal when it's rated for 4volts and audiocontrol is rated @ 9volts)

Example Videos:

1) http://www.youtube.com/watch?v=MDszfgEAz44

2) http://www.youtube.com/watch?v=umhfp_XwE0E

Click to read more...

 

[Z1NONLY 10+ year member]

Was there some sort of "event" (noises etc) between when you were happy with it and now? Or did you just turn it on one day and find it this way?

 

[Kastlez_ 10+ year member]

Was there some sort of "event" (noises etc) between when you were happy with it and now? Or did you just turn it on one day and find it this way?

Just recently I pulled it out and noticed.

I removed it from the vehicle and tested it with direct input from Ipod using a AUX cable.

Even with the audiocontrol turned up 10% I was getting readings up to 5volts

I changed systems alot over the years so couldn't tell you what "event" caused it.

Also should note i've always noticed from listening to different amplifiers/subwoofers/enclosures "IN MY VEHICLE" over the years none of them have

ever had the same sound/output as other systems. I know every system varies but something always seemed off about my output at all volumes. I feel like they all had so much more in them but were limited for some reason.... (Settings are not the issue here either i've been through them a million and one times lol)

 

[Z1NONLY 10+ year member]

If a hand held unit sounds fine, (ipod) and different HU's have a low voltage output issue, it's most likely the the ground or power used by all your HU's in that car that's your problem.

My next step would be to use some 16-18 gauge speaker. Run it out the window and directly to my battery + and -. Then connect both the switched and constant power leads together, then to the speaker cable +. (And ground to the - of course)

This will remove some variables from the problem. If it works properly there, then you know you have a problem with stock power. (I suspect ground, but it could be either)

 

[Dirtrider4eva 10+ year member]

If a hand held unit sounds fine, (ipod) and different HU's have a low voltage output issue, it's most likely the the ground or power used by all your HU's in that car that's your problem.

This ..

Check the ground it was my problem.

Or open it up and check the board and connections

Your front battery may be dying or getting parasitic drain, resulting in less power to the hu, but the good batteries arefeeding the amps.

 

[Z1NONLY 10+ year member]

I also forgot to mention the RCA between the HU and the line driver. That's the easiest thing to check, if you have another "known good" rca cable laying around.

 

[Kastlez_ 10+ year member]

If a hand held unit sounds fine, (ipod) and different HU's have a low voltage output issue, it's most likely the the ground or power used by all your HU's in that car that's your problem.
My next step would be to use some 16-18 gauge speaker. Run it out the window and directly to my battery + and -. Then connect both the switched and constant power leads together, then to the speaker cable +. (And ground to the - of course)

This will remove some variables from the problem. If it works properly there, then you know you have a problem with stock power. (I suspect ground, but it could be either)

I'll have to try this next. THANKS

I also forgot to mention the RCA between the HU and the line driver. That's the easiest thing to check, if you have another "known good" rca cable laying around.

I had some brand new ones sitting around and had the same issue.