Alpine 9805 deck

[skooter]

I have a Alpine 9805 cd head unit and it is driving me crazy! It skips all the time and Alpine says that it is a dirty disk or to much vibration. Are Alpines noted to be so sensitive that they skip. It skips just sitting in the driveway and I don't have all that much bass. I have a JVC 620 and you can put a disk in it that looks like it has had sandpaper run over it and it hardley ever skips. Thanks.

[error401]

Originally posted by skooter
I have a Alpine 9805 cd head unit and it is driving me crazy! It skips all the time and Alpine says that it is a dirty disk or to much vibration. Are Alpines noted to be so sensitive that they skip. It skips just sitting in the driveway and I don't have all that much bass. I have a JVC 620 and you can put a disk in it that looks like it has had sandpaper run over it and it hardley ever skips. Thanks.

I don't have too much advice, but my old CDA-9853 (before it got stolen) was almost as bad as you're describing. The tiniest scratch on the disk would cause it to skip, even while playing MP3s, which it would presumably have time to buffer and correct... Heck, it even happened on brand new just-out-of-shrinkwrap CDs. Maybe the lens just gets dirtied easily? The problem seemed to get worse later into the unit's life.

Replaced it with a Pioneer unit.

[I Am An Idiot]

How old is a 9805?

[skooter]

I am thinking it was 2003 when it was made, so it is around 4 years old.

[ppia600]

As far back as I can remember, Alpine has had pretty much the worst "skip protection" I've ever seen. Their decks have always sounded superb but I've had more Alpines returned because of skipping than any other deck we've sold.(back when we sold the brand) I can even remember alpine bragging in some of their CA&E ads about their special anti resonant cd chassis components (mainly the laser assembly) that made them very skip resistant. And it didn't seem to matter how well the decks were mounted to the chassis of the vehicles, although some of the customers bought the decks out the door and did the installs themselves.

[skooter]

I am lookin at the Pioneer deck DEH-P2900MP. What do ya think? are pioneers prone to skip?

[1moreamp]

Originally posted by skooter
I am lookin at the Pioneer deck DEH-P2900MP. What do ya think? are pioneers prone to skip?

Pioneers are prone to RCA ground failures lol lol But skipping is not one of their big issues. Just overdrive your amps one time and the ground circuit fro the RCAs blows out like a fuse...

[ppia600]

I haven't found pioneer to be skip prone. In fact, pioneer is usually the brand I usually recommend. Heck, even the newer JVC decks are more skip resistant than the Alpines we used to sell. Of course, I'm sure alpine has improved their decks every year since then. I can't remember the exact year we quit carrying them. Maybe 04/05??? I have a kenwood and with the two 12" I'm running, it will skip occasionally on just the right frequency, but usually not. It DEFINATELY can't skip when I use the usb memory sticks though. If you're going for a new deck, and if you're considering pioneer, the dehp6900ib has a usb cable you can run memory sticks or ipod on. If you want one lower priced, but still capable of running an ipod you can use the dehp4900ib. The ib series is ipod direct capable and will charge the ipod and allow you to use it like a cd changer and keep your ipod hidden. I'm actually thinking of selling my Kenwood and getting the 6900ib because when I bought the Kenwood we didn't have the new ib pioneers. Maybe I should have waited, haha.

[ppia600]

Originally posted by justonemoreamp



Pioneers are prone to RCA ground failures lol lol But skipping is not one of their big issues. Just overdrive your amps one time and the ground circuit fro the RCAs blows out like a fuse...

/\ Haven't you ever noticed the zig zag pattern of the ground traces and how they are thin? Its kind of strange because they still connect to the main ground after the short thin run. I'm sure they do it for a reason otherwise they'd just solder the rca ground pins directly to the main chassis ground trace. The only time I've seen it happen (to any deck for that matter) is when the customer either:
-had a crappy loose amp ground wire dangling from the underside of the trunk
-had a crappy flea market brand amp that crapped out and sent + voltage directly into the decks rca ground circuit
-did a poor installation job wedging the deck in so tight that the rca cables were smashed up against the wall of the dash causing internal stress and vibration that caused the deck's rca grounds to crack loose from the circuit board (Jvc decks used to be more prone to this happening)
But they are good about not having engine noise, if the amp is grounded correctly and doesn't cause the internal ground of the deck's rca's to burn. A simple solution if you are worried about that is to put a ground loop isolator between the subwoofer rca jacks and the sub amp's rca cables. It will be impossible for the amp to cause problems with the deck after that. Cheap insurance

Also, what do you mean by "overdrive" your amps? I've owned mainly pioneer before my current kenwood and I"ve never blown the ground traces. I've repaired them a few times for abusive customers though. I guess I've never "overdriven" my amps.

[1moreamp]

When you drive your amps into clipping the signal passes thru a output filter < a cap and a resistor to ground. All the excess hash that you don't want going to you speaker loads through this into the RCA ground circuit all the way back up to the HU where circuit traces blow like fuses.

I have seen this so many times over the last twenty I can not even begin to give you a correct repair count.

If you doubt this then please do a thought experiment and ask yourself where all the clipped hash goes inside your amp.

I stock 4.7 ohm 2 to 5 watt resistors for ZED amps that overdriven into clipping hard like this.

Plus remember speaker ground is also RCA ground on most amps and is also the center-tap of the toroid secondary, the only outside connection is thru the RCA shield all the way back up to the HU.
At the HU it can find true 12 volt ground, which is not available anywhere else in the entire circuit. Hence the blown ground traces on the HU's due to over cranked amps, by over zealous owners.


Clipped information has to go somewhere, and that somewhere is either your soon to be fried speakers or the RCA shield ground in the HU.

VIOLA Blown RCA grounds, and especially on Pioneer. We fix between 40 to 60 HU's a day at my shop, All brands, all makes, all the time...