Can my HU be causing a decrease in volume if it is going bad?

[FSUNole17 10+ year member]

Ok, this is kind of odd. I have a killer setup (Boston Acoustic Pro components hooked up to a JL 300/2, 12W7 hooked up to a RF 1001bd monoblock amp all running off of a pioneer premier 860, an older model HU). Anyways, my CD, FM, and XM music ALL play at a lower volume than when I first hooked it up. I am 99.9% confident that the amps and speakers are all still good. I have noticed my HU has had some issues (sometimes the face won't open, there are 2 solid lines in the display that won't go away that shouldn't be there) but nothing that makes you think it is having an effect on the audio, except the decreased sound. The songs still play clear and no distortion, anything like that, just lower volume. Can the HU be causing this or something else? The reason I don't think it is the amps is because that both the sub and components play lower than what they normally did. Thanks for the info, and if it isn't infact the HU, what do you think it could be?

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[T.I.K. 10+ year member]

Does an ex-drill instructor make a good counselor?

 

[retrojordans 10+ year member]

Ok, this is kind of odd. I have a killer setup (Boston Acoustic Pro components hooked up to a JL 300/2, 12W7 hooked up to a RF 1001bd monoblock amp all running off of a pioneer premier 860, an older model HU). Anyways, my CD, FM, and XM music ALL play at a lower volume than when I first hooked it up. I am 99.9% confident that the amps and speakers are all still good. I have noticed my HU has had some issues (sometimes the face won't open, there are 2 solid lines in the display that won't go away that shouldn't be there) but nothing that makes you think it is having an effect on the audio, except the decreased sound. The songs still play clear and no distortion, anything like that, just lower volume. Can the HU be causing this or something else? The reason I don't think it is the amps is because that both the sub and components play lower than what they normally did. Thanks for the info, and if it isn't infact the HU, what do you think it could be?

I mean I'd be inclined to say (without running a diagnosis and or taking it apart) that by deduction if there are issues with parts of the radio e.g. the lines, the opening mechanism (which could be the gears or motors or any number of things) etc...There are probably other issues with the radio concerning the built in amplifier circuitry.

If something happened to the radio to make the lines on the screen, and affect the opening motors/actuators it is totally possible other things could be affected such as the internal line driver.

That head unit puts out 6.5v pre-outs and the circuitry producing those voltage levels would be what affects the volume, a lowering in those would require you to re balance your amp's gains to match the head unit's sagging voltage.

I recommend testing the pre-out voltage of the head unit then re-matching that voltage to your amp's gain, and possibly adding an external Line driver regardless of the results.

 

[FSUNole17 10+ year member]

I mean I'd be inclined to say (without running a diagnosis and or taking it apart) that by deduction if there are issues with parts of the radio e.g. the lines, the opening mechanism (which could be the gears or motors or any number of things) etc...There are probably other issues with the radio concerning the built in amplifier circuitry.
If something happened to the radio to make the lines on the screen, and affect the opening motors/actuators it is totally possible other things could be affected such as the internal line driver.

That head unit puts out 6.5v pre-outs and the circuitry producing those voltage levels would be what affects the volume, a lowering in those would require you to re balance your amp's gains to match the head unit's sagging voltage.

I recommend testing the pre-out voltage of the head unit then re-matching that voltage to your amp's gain, and possibly adding an external Line driver regardless of the results.

Thank you for the reply. So basically a great way to test this sounds like to test the voltage of the pre-outs to see if it has decreased? If it has dramatically decreased, I think I may just get a new HU because I don't want to max out the amps on the gain. But this leads me to another question, outside of testing the voltage, are there other ways to test the HU to see if it is the problem outside of shipping it off to be examined by Pioneer?

 

[retrojordans 10+ year member]

It's hard to recommend anything with any confidence without hearing it and checking everything out. If it's new(er), and under warranty send it back if that wouldn't cost much. If sending it back would cost $100-200 or more, think about checking Craigslist I found my Kenwood DDX6019 Double Din dvd unit for $250 and it's as good as brand new...For a line driver I checked Craigslist once again and came across an Audio Control Matrix for $50 again as good as new...So if you need a new head unit anyway, there are deals to be had.

I mean like I said, if it would be reasonable to send the radio back for warrantied service/refurbishing then I'd do it, but if they want to charge ya $200 to repair it, it is not worth it, there are $800-$1000 gently used units out there for $250-300 e.g. Pioneer Avic units MSRP in 2005 - $2500 Craigslist - $350.

Odds are it's just time to replace it :/ ***** but...What ya gonna do.