81coupeowner

Let me start off by saying this is a low budge build. I have a Rockford fosgate 4060 amp iv had for years. It was working fine when I pulled it from my truck a couple of years ago. I finally decided to use it again to power a sub. The amp is installed and powers on but I get now sound when plugged into the radio. I have a red jvc double din radio so yes I'm plugged into the rca out. If I plug my iPhone into the rca inputs on the amp it plays music. I called tech support at crutchfield they suggested the radio was defective and shipped me a new one. Still the same issue. Could the new rca voltage of 4 volts not be compatible with the old style amp? Any advice would be appreciated. Thank you Jason

markcz

Is the amp properly set up to recieve a low frequency signal? (proper inputs selected, LP/HP switch on LP, freq **** turned up to max, gain **** turned up to max)

Some radios can turn individual RCA outputs on/off. Are you sure yours is set to have the sub output go out thru the plugs you're connected to? Is your HU LP filter set at max freq possible?

If all of the above are correct, try different RCA cables. If still not working, any local audio shop should be able to find the issue in just a few minutes.

81coupeowner

This is a old fosgate 4060 amp it has both rca and speaker wire inputs, but there is no switch on it to say which one to use. If I use my iPhone plugged into the rca Input it plays music. On the radio I have the low pass rca out set to 80hz. Crossover point. I have replaced the cables as well. I'm wondering if the rca voltage is not a match for the amp.

Mike Beck

For the heck of it don't use the low freq bypass for now. Obviously the amp is good since you can hear your I Phone through it.

I recently ran into a problem where the amp would not stay on due to a low voltage dc signal coming out of the rca outputs of the head unit. To check for this, run one rca from the head unit into the amp, and run your I Phone into the other rca input to the amp. See if the phone still plays through the amp.

markcz

Do you have a trigger wire connected from the HU to the amp? And does the amp power up with radio, even though you can't hear anything?

The only 4060 instructions I could find online are HERE. Do you have the sub wired correctly?

Double check settings on HU to make sure you have an output on the RCA's you're using

81coupeowner

First off thank you for the replies. Yes mark the remote on sire is connected to the head unit and the amp powers on. Mike Don't you need the same signal in both rca inputs for it to see the correct signal? I do know my radio says the preamp outputs are 4 volts. I'm wondering if this is not compatible with the old amp. I don't think they used that much voltage back in the day. I have thought about using the high pass connections but then I lose the cross over point from the radio. I have a stand alone cross over I'm going to put in between the amp and radio and see if that works.

81coupeowner

Oh mark yea about output coming from the radio. I thought that might have been a issue so I called crutchfield and talked to there tech support. They said looks like the radio I'd defective so I returned it to them. I had both a kenwood ddx371 that is no longer made. So I got a jvc kw-v200bt now. I still have the same issue.

markcz

4v is the maximum output at full volume, that's not the issue.

I still think you have a setting, or combination of settings, wrong on the HU/amp.

Take it to a local audio shop, should be working in under an hour

81coupeowner

I'm thinking I might have to. I hate to spend money to have them tell me the amp it just wore out.

Mike Beck

You can run your iPhone into one RCA and the head unit into the other RCA. Yeah, you will hear two different things happening at the same time, but it will show you that it works.

Is it possible that the RCA outputs from your head unit are not active? I know my Pioneer stuff will not send a signal out of the subwoofer RCA jacks unless I actually enable it. Take a look.

How about the "normal" RCA outputs? Have you tried them out of your head unit?

As Mark said, the 4 volt output is not an issue.

81coupeowner

Yes i have tried the front rear and sub out. Iv read the book and don't see where the preamp outs have to be enabled. My brother has another amp I'm going to try. It's very perplexing to me.

markcz

If the amp works with an ipod input, that's prob not the problem

81coupeowner

Well after calling jvc this evening and confirming that the preamp outs are turned on. I'm going to change the amp and see if that works.