Doing my Marv install....ran into a hiccup

First things first.....Mr. Marv is freakin awesome!

Second, here's the rundown of the equipment I have


HAT Clarus 6.5's up front
JL Audio HD600/4 (bridged two channels for the sub)

The sub is working great, got that working yesterday but today was installing the speakers, crossovers, and running all of the wiring. Long story short it wasn't too bad although getting the wires through the driver side boot is a biatch

What's happening now though is when I turn the truck on to test the system, the sub plays, the rear speakers I left connected to the head unit play, but all I hear is static from the tweeters and a very slight sound from the Clarus speakers.

I followed JL Audio's directions on setting the gain/input sensitivity on the front speakers and at 3/4 volume (set to 30 on my pioneer) out of the amp it is doing the recommended voltage (24V? can't remember off the top of my head).

Measuring the voltage through at the crossover at the door speaker itself at a volume of 10 I only get a voltage of .7-1V. Seems extremely low to me but I don't want to bump the gain up and fry my crossover / speakers. Anyone have an idea of what I should check next?

 

My first trouble shooting step would be to take any speaker on hand and directly connect it to one of the front amp channels. Start out really low on the headunit volume and turn it up a bit at a time until you are satisfied the speaker is/isn't playing properly. That as a step one will tell you if the problem is before or after the new speaker connections at the amp. Troubleshooting can branch either way after that.

 

Alright directly hooked up one of the speakers and it's still doing the same thing...sub is working and I can faintly hear voices in the Clarus but very low. I'm a little iffy on turning the gain/sensitivity up more on the front speaker amp controls because it's almost matched to what my sub is set at currently.

I'm wondering if it's a setting with the amp...I have the HP filter turned on for the direct connect but had it off while it was hooked up to the crossover. Past that I have the RCA cable from the back of my pioneer going into the amp and have it set to 2 channel input (other option is four). Thanks for your help ^^

 

Here's a thought...I was digging around in my headunit and I remembered this drawing:



I'm currently using the lowest RCA connections (subwoofer out)....inside the headunit under the subwoofer section there's a frequency tab that looks like it's a LPF. I'm tempted to swap the RCA cables over to the front or rear output to see if that's the problem...

 

Alright so I think that the RCA connection is my issue...as well as headunit settings but I'm at a loss as to what to do.



Obviously can't read anything here but the frequency is the low pass filter for the sub output....it was set to 50 Hz, at 125 I can hear the music much more clearly (obviously) from the door speakers now but still not to any decent amount. I tried hooking the RCA's up to the Front Output terminals but nothing doing, no signal to the sub or doors. Any thoughts? I figure at this point it has to be something stupid that I'm overlooking.

 

What rca outputs do you have you rcas in on the headunit?
Edit: Just saw you switched them. You need another set of rcas, one for sub and one for the clarus speakers.

 

Yep it was something stupid....unplugged it and attached to the "actual" front outputs lol. I had it attached to the rear outputs and had the signal shifted all the way forward. Now I need to adjust the subwoofer again though because I don't have the software option to increase the bass anymore :/

 

I don't understand. You should have one pair of RCA cables going from the front output on the headunit to the amp, and a second set of RCA cables running from the sub output on the headunit to the amp. If the headunit has only one sub out connector, then it would be acceptable to use an RCA cable splitter (two into one thing). Since you are bridging the rear two channels on the amp for the sub, you need both channels to be fed something, hence the two sub input cables. That should allow the headunit to tailor the Clarus set as well as provide for sub tuning.

 

Alright, that makes sense and I had actually been wondering that while I was taking a break. Seems silly to have sub controls in the headunit that would be rendered unusable by forcing you to run a set of cables from the front output. As much as I hate to go to that store....best buy has a 4 channel rca cable for sale. I might buy that because I need to get my truck up and running by monday. Thanks for clearing everything up, I have really been taking my time with this install so I didn't understand why they speakers weren't working.

 

Well as an update, all of the audio equipment is installed and working. My first opinions are that I'm glad I didn't get a bigger sub because this is more than enough for the rock that I listen to...as a side note though my tweeters are making a buzzing / humming noise when the volume is low or off.

That being said I searched and it seems to be one of two things....the amp ground needs to be moved from the seat bolt to another location....or my headunit is being finnicky. Going to try moving the ground later in the week to see if that clears up the problem.

Past that I would highly recommend the Hybrid 6.5's that Mr. Marv suggests because the music I listen to is now so clear, that I've realized I need to redownload some of my old cd rips because of how bad the quality is.

Thanks a lot for the help Lbridges...I knew I was overlooking something but didn't realize what it was.

 

You're welcome - not sure if you already knew, but the guy behind Hybrid Audio is Scott Buwalda (spelling?), a multi-time national sound quality champion.

Not sure I ever read, but by any chance do you have a pioneer headunit? On the high end units they had a reputation for blowing out a micro-fuse in the output section if ever hooked up wrong. A fix, without sending in for repair, was to wrap the outer, metal, portion of the RCA cable with a wire and grounding that. I forget why this works, but I remember folks on DIYMobileAudio writing about it for the 880PRS headunit. And yes, seat/seltbelt bolts are not generally a good place to use for a ground. That's because the cab sometimes gets painted after the attachment nut is welded to the body, then the threads just don't make good contact for a ground connection.

 

Alright joined the DIYMobileAudio forum and have just discovered the vast world of " Pioneer Blow Pico Fuse " threads....good night that's a common problem. Hopefully it's just a ground issue that I have because I was pretty careful to keep the battery disconnect / power turned off and to not hot swap the RCA's but at least I have a solid second solution to try if the ground swap doesn't work. I'll keep you updated on what happens, hopefully I'll be able to swap the ground tonight because I'm curious now.

Here's the thread if anyone is reading this and is curious about it:

http://www.diymobileaudio.com/forum...3889-pioneer-rca-preout-noise-prevention.html

 

Well here's an update on the droning / buzzing from the tweeters...

Read several sites that gave the basic rundown of trouble shooting the problem:

1) Shift the ground on the amp to a new location ( I moved the ground to the back wall seat back bracket and made sure it was contacting metal....buzz stayed)

2) Unplugged the RCA's from the amp and turned the truck back on and the sound went away....so nothing related to the speaker wires.

3) Found out that the Pioneer RCA grounding issue is very widespread so I grounded all of the RCA outputs on the back of the headunit but if it did anything it was minimal (seemed quieter however).

4) Bought a ground loop isolator from Amazon (it was 13 bucks with free shipping so I said what the hell) but that was a waste of time / money - which most of the websites said in the first place.

5) Last and not least I got irritated and decided to shift the RCAs from running by the power / speaker wires to running down the middle of the vehicle and the sound went away.

That being said I'm not sure if a combination of the Pioneer RCA grounding trick + shifting some wires around worked to get rid of the noise but I'm just glad it's gone because it was driving me insane! I've talked to Mr. Marv - and read on three sites now that the power running with the RCA's and causing issues is a myth (or it was valid in the past) so I'm just going to assume that it was an install issue since this was my first audio endeavor.

 

I know from personal experience on my previous Toyota daily driver that moving the power and RCA cables from the channel at the bottom of the driver's side door frame over to the passenger's side made the noise go away. No changes were made in the cables other than where they were routed. I attributed this to some data signal that was noisy, but since moving the cable fixed the issue I quit investigating.

As an aside I suggest reading up on topics at the Basic Car Audio Electronics site. Don't have to read each article to fully understand. Just peruse for topics and know there's a place (if you bookmark it) to go back to for reference material. For example, item #62 at BCAE addresses a primary cause for ground loop noise.

 

I blew the pico fuse in my pioneer, had a terrible time troubleshooting until I found the solution. Grounded the rca shields to the head unit frame and problem solved. As a rule I never run my rca's near the power cable, even though they're shielded, you're generally asking for problems.