Alpine CDA-9887 RCA Ground

[AlterEgo99 5,000+ posts]

I've read through the entire ground loop thread relating to Pioneer HU's and their inherent RCA grounding problem. In that instance it appears that for a lot of owners of that brand of HU that wrapping the RCA output shields with a ground wire and grounding that wire to the HU chassis fixes the alternator whine issue.

I was wondering, as someone suggested to me in another thread, that I may want to try the same approach with my Alpine CDA-9887 HU. As this is not a Pioneer I am curious if this is safe to do on an Alpine? Does anyone else have an Alpine CDA-9887 or similar model who has done this? Just curious.

Thanks!

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[ejschultz 10+ year member]

From the electrical standpoint, it is safe. However, if you don't have a need to do it, why go through the trouble to ground them? If you have some noise, it may help, but depending on the internal electronics of the 9887 it may introduce noise. I used a 9855 in my car until about a week ago and never had any problems what so ever. I even had my box slide and literally rip the RCAs for my mono amp. This would definitely blow the pico fuse I've got in my new p800prs but it did nothing to the alpine; I did have to purchase another 18 feet of RCAs to replace the damaged ones though. Basically, the moral of that "story" is even if you hot swap with the alpine, you won't screw up any internal on the hu. Well, I'm sure if you were to sit there and unplug and plug in the RCAs you'd probably run into some sort of problem, but doing it here or there shouldn't and more than likely won't affect anything. You can try and ground them, but you probably won't have any difference.

 

[AlterEgo99 5,000+ posts]

Agreed. I'm going to be using some step by step instructions, starting with the amp RCA's, to trace my issue and see if I can determine where the noise is being introduced into the system. I've tried a few guesses by changing ground points, ground loop isolators and even a new high speed iPod cable, all to no avail. So, it is time to **** it up, listen to the experts, and use their step by step instructions to see if I can isolate the problem.

In case anyone wants to know, here are two of the links from whom I have downloaded their step by step instructions. I am hopeful than by doing this I will be able to determine the source and correct it:

http://www.termpro.com/articles/noise.html

http://www.docstoc.com/docs/2423218/How-can-you-eliminate-alternator-whine-in-a-car-audio-system

The whine is most noticeable on my iPod source, which happens to the be main source I use to listen to music. I also get some hissing on this source. The whine is barely audible on the CD source (with no CD in the player and the volume up) and there is no hissing. So, starting tomorrow AM, the fun will commence! //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif

 

[ejschultz 10+ year member]

The hiss you hear is the alpine itself. Every alpine I've had, full speed or not, has had a hiss with the iPod. The whine definitely sounds like a ground issue. Unfortunately, I do not believe there is a way to eliminate the hiss. That's one reason I switched from my 9855 to my p800prs. I've heard many good things about all the pioneer head units as far as iPod sq goes. The p800prs is not full speed and I have absolutely no hiss, even with the volume at 62 (max).

 

[AlterEgo99 5,000+ posts]

Interesting. The main thing I like about the Alpine is the Imprint Sound software to tune the soundstage for the vehicle. That feature is awesome! I could deal with the hiss as it is not that bad if I can just get rid of the whine, which I intend to work on this weekend. It's not a loud whine but noticeable enough at high volumes between songs or at very quiet points that it is annoying. Most would probably not even hear it if it wasn't pointed out, but I guess that may just be me! //content.invisioncic.com/y282845/emoticons/cool.gif.3bcaf8f141236c00f8044d07150e34f7.gif

 

[ejschultz 10+ year member]

I hear ya on that one. Over the last few years, I've been finding myself pointing out faults in almost every audio system I listen to. I'm becoming an extreme audiophile and I'm not sure if I like it. I'm finding it harder and harder to be pleased with audio reproduction. And as you probably know, this isn't a cheap hobby, especially when you change and upgrade things every few months.

 

[AlterEgo99 5,000+ posts]

I wouldn't exactly say I am overly concerned about the exact reproduction of every note but within the confines of a vehicle, getting some clean sounding music is fleeting at best. Combine that with certain "noise" and it can drive you crazy. I love the Imprint software as it really tailors the soundstage to the vehicle. I tried setting everything manually using the built-in parametric analyzer in my Alpine HU and the ability to set signal delays per speaker and then compared that to what the Imprint software came up with. Wow. My settings I thought sounded good but I ended up setting the gains way too high on the amps and the overall sound was very harsh compared to Imprint. And I love being able to set the soundstage based on my seating position in the driver seat. Nothing like have a smooth spectrum curve with the vocals being matched exactly at center stage - in front, center dash. Pretty amazing. Now if I can get rid of this **** whine I'll be happy! //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[ejschultz 10+ year member]

I liked the abilities of my 9855. It has all the same stuff as the 9887 but no imprint. I always used the 5 band parametric eq, not the 7 band graphic. I played around with the ta but I'm not really that good at it. As far as my p800prs goes, there's no parametric eq, but a dual left/right 16 band graphic eq. I find this a lot more useful than a 5 band parametric. Also, with the pioneer, I'm able to basically control each speaker seperatly. Level, crossover point and slope, eq (for left/right), and obviously ta. Like I said about ta, I'm not very good at setting it, but it comes with a mic so it can be set up. The mic also does auto eq, but that's more fun to play with on my own. I was a die hard alpine fan for years; it was all I'd use. I did a lot of research on the 9887 and the p800prs and went out on a limb and got the pioneer. Honestly, it's the best sounding hu I've ever had. I hate to say it, but I think from now on, at least until I'm ready to drop a grand on an sq hu, I'm going to stick with pioneer. I just have to be careful with those pico fuses.

 

[AlterEgo99 5,000+ posts]

I installed a noise filter on the constant 12V power lead to the HU and that appears to have done the trick...I can barely hear the whine now and not at all when the truck is movin' down the road. I may still test wiring the 12V constant directly to the battery and see if that totally eliminates the whine but right now it seems quite acceptable.