Which signal converter? I need a new one.

YzGyz

I upgraded my Z sound system a few weeks ago (just speakers, amps and sub, kept stock head unit). I have the dreaded wheeze that get louder with more revs. It's not crazy loud but it bother me. I put in a lot of time and $$ to have a good clean music. It took a while but after redoing my ground, and testing out the wires, I found that it's simple unclean signal from my signal converter. I tested this by using a 1/8 jack to RCA wire (female) into my phone and connected to the longer RCA that I ran to the amps. Sure enough, it was clean sound. I reved my engine to 5k and clean unlike with the PAC signal converter.

My PAC leads are solder to the wires that feed the front right dash speakers.
So, what converter are you guys using and where can I buy it for the cheapest price shipped to Houston?

SouthArk370Z

Before investing in a new converter, I'd try grounding different parts of the installed one and see if the noise disappears. I keep a piece of 16ga zip cord (lots of strands so very flexible; enough ampacity for most auto purposes) with alligator clips on both ends in my toolbox - comes in handy for jobs like this.

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sselemit

You have bose?

RonRizz

Grounding is your issue here. seek and you shall find. If all else fails, I've always had good luck with audio control products.

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YzGyz

I called PAC tech support and they told me thing's I already know. I'm 99% sure it's the converter itself. When I disconnect the long RCA that is connected to the amps where they plug into the PAC converter and feed it audio from another source, I have clear music. I get no feedback noise or grounding noise at all. Si that mean the feedback/grounding noise is coming from after that connection. The only thing left is PAC line converter and the source of signal. The PAC feed is soldered into the front dash speaker terminals itself. Heck, everything connection that was bare wire was soldered before I ripped everything out to trace the noise. I wish I had a 2nd converter so I may may a definite rule out of the PAC SOEM-T. My bro has one but it's buried deep under his system and would be a big pain to get out, grr... I'm not gonna mess with his system.

As for grounding the pac ( blue/black wire iirc), i grounded that to the same block that grounds my amps. I know they are good because again, with an external audio feed; I get clear sound.

RonRizz

Two things.... first, are you sure you have your gains set properly on both converter and amplifier? second, that unit also has a signal ground that you may have to connect. check your literature and connect as advised. it may or may not help.
Ok, Three things.... you cannot simply connect your ipod/phone/ect to the rca cables running to the amp to help rule out noise sources because they are not grounded to the chassis of the vehicle, as are all the other integral components of your system. you need to stay in the realm of your current problem (although you have given it more thought than most would have, and should be commended for doing so).
Finding the source of the dreaded alternator whine can be a very simple task, or a long and tedious one. I've spent more than my share of time re-routing wires, checking solder joints, ect... I feel your pain, and wish you well.
At your wits end, consider the Audio Control LC2i.

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SouthArk370Z

The PAC SOEM-T gets good reviews on Amazon so changing the adapter may not fix your problem. But if it's worth $80 or so to you to try it, why not? Maybe you got a bad PAC SOEM-T.

I'm with RonRizz that it's probably a grounding problem. Audio systems can be very intolerant of high-resistance grounds, ground loops, &c. As he mentioned, even the position of a wire can cause interference problems.

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bigaudiofanat

Late to the party here, as the others stated check your ground. I know audio control recommends that you ground their unit to the same ground as your amp, on top of that they also recommend running the ground of the amp directly to the battery which I have never had to do. Unplug the RCA's from the amp and see if the noise is still there, this will help track down what is causing the problem. And as stated X2 on the LCi2

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YzGyz

No noise what-so-ever when I unplug my RCA. I get no music either (no duh!). So freeking frustrating! I'm gonna clean my car up a little for now. I'm gonna go out for a drink or two later.. grrr.. stupid radio!!!

SouthArk370Z

That sounds like bad shielding on the cable going to the RCA connector.* Which could be a ground problem. Try wrapping your hand(s) around the cable and see if that attenuates the whine (doesn't always work).

*Edit: the cable is acting like an antenna

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YzGyz

I'm not following on which wires to wrap my hands around. The RCA leads coming out of the signal converter or where the long RCA and signal converter meet? I'm going to take pictures of the install tomorrow. My wires are a little to long and are a little messy but that's because I wanted some slack as I hunt down this noise.

RonRizz

Think of it as a chain, starting at the back, you disconnected your rcas from your amp. Now there is nothing before your speakers to cause noise EXCEPT your amp. No noise means amp is not the issue. Now plug your rcas back into the amp (NOT WHILE SYSTEM IS TURNED ON, PLEASE) and unplug them from your converter. check for noise. No noise means noise not being introduced into rca cables. Power down, plug cables back into converter, disconnect speaker inputs from other side, ect, ect you get the point. If you are using the signal sensing turn on for your converter, you will have to power it main line when the speaker leads are disconnected, or it wont power up, and the remainder of the testing will be mute.
If all this leads to no help, drop your gains on that converter, and set them on your amp with a multimeter. You may be shoving that noise down your amps throat with too high of an input voltage. Way too much info before bed. lol

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P99rs Head Unit--- Amps- 2 Pioneer Prs800d --- Zapco ST1000MX---Zapco ST-4XSQ---- SI BM mk5 Subs---SI TM65v2 Midbass--- SI M3 mids--- SI M25 xbl2 tweeters ----- 2016 MECA street class 3rd place at world finals

RonRizz

I will add, now with a fresh morning head that your gain setting is much less likely the problem, than is a poor ground, or inferior rca cable, or just a plain bad converter. My head still leans to your grounding.

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P99rs Head Unit--- Amps- 2 Pioneer Prs800d --- Zapco ST1000MX---Zapco ST-4XSQ---- SI BM mk5 Subs---SI TM65v2 Midbass--- SI M3 mids--- SI M25 xbl2 tweeters ----- 2016 MECA street class 3rd place at world finals

a6walter1

I've had the LC2i all summer, and it has been awesome. It always amazes people when they get in the car and hear that sound with the stock HU.

Back to the question at hand, when there is a noise in the system, the culprit is almost always a grounding issue.

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YzGyz

Just updating those that had input on my problem with some confirmed findings. I finally got my hands on another signal converter tonight. I was right, the dang feedback was due to my defective line converter. I rigged up both line converter so that I can simply swap back and forth the RCAs. Both line converter received signal from the same place, no other changes in my sound system. The borrowed converter was perfect. Mine was not.

Conclusion: I need me a new signal converter. GRR!!!!! There goes another $30... Anyone read or have answer for my other post in the Nismo section on bluetooth? I meant to post it in this forum but clicked the wrong one. Sorry.

YzGyz