# JVC KT-SR1000 - Crackley sound



## JWKessler (Jun 3, 2004)

I just bought a JVC KT-SR1000 last weekend and have been enjoying it. It works flawlessley in the car, but at home I'm less pleased. The problem is a crackley sound - almost like static. It's most noticable on talk stations, and at first I thought it was related to a bad feed. But then I noticed all the talk stations had the same problem. Music tends to mask the noise, but it's present there as well.

I unplugged the audio cable from the base station and plugged it into my iPod. The sound is fine, so it's not the input to my sound system or the audio cable. I then connected a pair of head phones to the line out jack on the base unit. The level is a bit low, but it sounds fine that way as well.

Any one have similar experiances? I do notice the power cable has to be oriented just so or the base station looses power.

John K.


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## JWKessler (Jun 3, 2004)

Followup - I exchanged the base station with another and the problem persists. I've pretty much traced it to a power problem and believe it's a poor design.

The unit acts up when ever I switch on lights in the room where the Sirius receiver is located. Dimmers causes a buzzing sound and initial power on of a set of lamps causes the sound to totally cut out briefly.

I sent JVC a detailed e-mail but have received no reply yet. I'm now shopping for a better power supply - 12VDC at 2 Amps are needed.

John K.


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## Guest (Jun 10, 2004)

For what it's worth, I have the Audiovox and have not experienced this problem.
Until I get an antenna extension cable, I've been plugging the system into the sound card's audio input on my computer when at home.

It's weird that you don't get the problem with headphones.
Almost sounds like bad shielding on the cable you're using to go from the JVC unit to your audio receiver but you checked that with the iPod.

When you hit the lights and you lose audio, does anything appear on the Sirius receiver display - like "searching for signal" etc?
A long shot but wanted to throw that out there.


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## JWKessler (Jun 3, 2004)

No, the JVC does not appear to respond to the power glitches in anyway - other then to mess up the sound. I recently noticed that things like the diswasher starting or the electric water heater kicking in also will cause the sound to briefly cut out. I'm currently looking for a better 12VDC 2000MA power supply. Right now that is my #1 suspect.

Still no reply to my message to JVC.

I really like this unit in the car, but I would not recommend it for anyone who wants to use it at home, connected to a stereo system.

Thanks for the reply.


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## Guest (Jun 13, 2004)

I like the Audivox. It's a little bulkier than I'd like (compared to the XM Roady, for example) and it seems to run pretty hot but the display is excellent and the mobile dock has an audio out, an FM Tuner and an FM out (for directly connecting to your antenna, I assume).


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## Guest (Jun 25, 2004)

I got my SR1000 a couple of weeks ago and absolutely love it. the only problem I had is during installation I had to unplug the antenna and the cable came completely out of the plug, so now I'm searching for a replacement cable end or buying a new antenna. I'm curious if anyone has used the TERK antennas (since they seem to be the only manufacturer) and if they are any better than the stock antenna.
As for your noise - I have found that with my cassette adapter in one vehicle (because it suffers from intense noise on the radio) the audio is "tinny" - more noticeable on talk stations, but in the other car using FM rebroadcast it's the most excellent sound I've heard. 
In the home, you are very obviously getting some feedback from electrical fields because dimmers create an electrical field around themselves and in the wire as they absorb the extra electricity not going to the light. Since the noise isn't coming over headphones or your ipod, the cable to the stereo is picking up the interference and you may have to get a high-quailty shielded cable to eliminate that. A better shielded power supply would help with some of the problem, the interference leaking through the power line.
You may also find out that your home is not grounded well so a lot of the interference that should be absorbed into the house electrical ground is instead emitted. You could eliminate a lot of it by purchasing some surge protectors (which you need anyway) that feature RF Filtering and use them on your fridge, microwave and A/C 
Check out SYCOM Surge Protection - http://www.sycompower.com/product/united_states/

You could also use the car kit with re-broadcast in the house and it might do better.

anyone who knows where to get a good deal on an antenna please email me - [email protected]


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## JWKessler (Jun 3, 2004)

Problem Solved!

I finally tracked down the cause of my crackly sound - and it's very odd. Keeping in mind that the noise wasn't present when listening to the receiver with headphones or when listening to my iPod connected to the same audio cable, I began thinking about what was different under those circumstances.

The difference was the ground connection between my stereo receiver's audio input jacks and the JVC's ground point - which is apparantly connected to the AC power line ground through the power brick.

The iPod is battery powered so there is no ground path when listening to it, and of course using headphones breaks the ground path as well. So I thought I might have some sort of ground loop condition. Usually this causes hum or in a car you can hear alternator noise, so the idea seemed a bit far-fetched. Anyway I had a Radio Shack ground isolator from an old car stereo installation and I stuck it in the signal path. The sound has been clean ever since.

These ground isolators are basically a pair of 1:1 ratio audio transformers. They introduce a small amount of distortion (frequency response changes and phase shifts) but the change is hardly noticible, and the fix is absolute.

I still call this a design flaw in the JVC unit, but the fix is simple enough that I can now recommend it for home use. If JVC would add isolation in the power supply (easy to do) this problem would not exist.


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