Chesapeake

I am having a real difficult time figuring this out. I have the Nakamichi system in my 92 SC400.

Suddenly all the speakers are producing a "click click click" sound when the system is turned on. It does not seem to be volume sensitive nor does it respond to fade balance controls. I can hear the regular music in the background but faintly and distorted. The CD, FM etc seem to be functioning...

Any one had this problem or suggestions???

hwallen172

Does it make the noise when the engine isn't running? Also, does the noise vary with engine RPM?

lex400sc

Loose line-level signal connections. Somewhere between the receiver, CD changer, and amp, there is a loose RCA connection. If you can single out which sources the clicking occurs in that helps too.

CD only is a cable between receiver and CD changer.
Radio means from reciever to amp.

Chesapeake

It happens with engine off as well. With CD playing FM playing or AM playing...

Any suggestions as to where I may track down a loose connection? For example are all connectors at the head, amp etc?

Thanks...

lex400sc

Do you notice the popping sounds in the subwoofer as well? (There shouldn't be because the sub operates off a seperate amp in the Nak system). The botched connector could be the wiring harness from the recevier to the 4-channel amp. It's up to you to figure out which side and where it is.

Let me ask you this, are the speakers clicking continuously at a steady beat or does it vary when your car brakes hard and corners hard?

Chesapeake

The clicking is a regular pattern, but honestly have not compared when I was braking or cornering. I thought it was in the subwoofer also but not 100% sure will need to check that.

It is a regular click click click click and it seems to me does not vary whether the engine is on or off and does not seem to vary with the engine in park or accelerating etc.

strongsail

Try ejecting the cartridge from the CD player, then play the radio without the cartridge in the player - is the clicking still there?

I am making a s.w.a.g. that you do have a bad ground somewhere (like an RCA plug partly pulled out) and what you're hearing may be noise generated by the cd player's mechanism getting into the audio when a CD is spinning, which I think it does whenever the stereo is on and there's a CD in the player.

Even when the CD isn't playing music, the player is still reading data off the disc all the time so it can immediately start playing at the same spot on the disc that you were listening to last.

The "clicking" is a common problem when plugging a portable CD player into the aux inputs of a car deck, because the portable player and the car deck don't share a common power supply ground, and a filtered audio cable from Radio Shack solves that problem - but here, the system is designed to shield against that noise, so I suspect a bad ground. Check the audio connections at the CD player and at the power amp below it - - I haven't had my system out yet, so don't know exactly what's there, but if anything there is loose, or wet, or looks damaged, you may have found the source of the problem.

SupraCoup3

if you need any help w/ what wires do what, check this diagram on my site that 933005sp made. http://209.125.175.29/main.htm (left hand frame)

fire

I'm pretty sure it's your volume ****. It's separate from the head unit. If you disconnect the volume ****, the sytem goes to FULL volume. You could try that and see if the popping goes away or you could just try one you know is good.

Black94RX-7TT

The amp is under the CD changer. You'll have to pull the passenger side garnish & changer to get to it. The amp has 3 connectors. The changer has two connectors. Check for water in the area while you're back there. That harness goes through the rear firewall just under the decklid, and splits two ways. One goes forward just under the doorsill, the other goes across under the rear seat. On the driver's side of the car there are two bulkhead connectors (for all the signals that need to get to the driver's side harness), and part of it splits off and goes forward down the transmission tunnel (to the head unit I presume). Pull up the rear seat bottom and you'll see exactly what I am talking about.

I'm betting your amp is dying, or you've gotten something wet back there.

Black94RX-7TT

No....the Pioneer system has a separate sub amp. The Nakamichi system has a 5 channel amp.

Chesapeake

I have just spent three hours getting personal with my car here is what I have found.

Sound is in all speakers a low click click click I disconnected and removed 12stack CD changer. Still the sound in all speakers.

The set up is Nakamichi premium 4 (2 rear deck two door)speakers 1 sub two tweeters...


The amp has three connection plugs one out of forward end (I belive drives the sub) one forward on the outboard side and one aft still on the outboard side. (the aft outboard I believe is the amp input...)

I have the amp out of the car... how can I test it (can a good auto stereo shop do this?) And if bad, what is a really moderate priced quality replacement for it with the same plug configuration size etc etc?)

Is it possible the head unit is the source? And what are my replacement options with that? How might I check the head unit? and where might there be some loose connections at that end?

Sorry for all the qustions, but I am trying to give you all the data as I know it...
THIS IS REALLY a GREAT forum and I do want to thank you all in advance for your cool help!!!

Chesapeake

strongsail

Okay, here's another thought: is the clicking there when there is no cassette in the head unit? This mechanism will have its capstan motor running when there's a cassette inserted, even if you are listening to the radio.

If the clicking is cyclic and constant, I am still pointed toward a bad ground and the noise being generated by an electric motor. The clicking is there when the engine is off, with the ignition switch in the ACC position, right? That rules out the fuel pump motor and the alternator as noise sources.

Is the noise there with the heater fan off? I think the fan will run in the ACC position, but am working from (admittedly sometimes faulty) memory on that one.

And I agree, this forum (and the UK-based LSOC site too) is great. Talking about the car isn't quite as much fun as driving it, but it's great sorting through all these details and making new friends!

strongsail

And yes, a competent audio shop should be able to bench test your power amp and tell you if it has a problem. Fitting a new amp? Boy, your options are pretty broad there - but forget the matching plug/socket idea - you will have to adapt the wiring to a new amp, but there are wiring diagrams available here and on the LSOC site that will help in that regard. And then there's the issue of it physically fitting back in the same spot - doubtful there too, since the Nak amp was designed to fit that hole under the changer - but you may get another one to fit in there, but may not be able to use the original mounting setup.

But at this point, since you have your amp out, you know more than I do about the shape/size of the hole and the way the amp was bolted in.

Everything I have read so far seems to imply that the Nak amp is pretty reliable and hard to hurt. Hope your problem ends up simple and cheap to fix - -

strongsail

Just re-read your last post and noticed you using the words "forward," "aft," and "outboard" in describing your amp - and you're from the Chesapeake - you gotta be a boater! Sail or power?