Speaker level inputs on ads P440 not working

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I am so bummed. I just got done testing my ads P440 amp using speaker level inputs and it doesn't work. I created some RCA adapters to connect the speaker wires from my factory stereo to the inputs on my ads P440 amp. I connected the power, the remote, the speakers, the RCA's. Everything looked good at first. I had a blue power light on the amp showing that it was powered up and ready to go. But as soon as I turned on the stereo the power light on the amp went out. I spent some time trying different configurations, bridged and un-bridged. But what I found was that as soon I connected the RCA's to the inputs the power light on the amp went out. In fact, all I have to do is touch one of the speaker wires to the input and the amp powers off (even with the volume turned all the way down). I guess at this point I have to assume that this amp will only accept line level inputs. Let me know if you think I missed something.

what is the source you are using ? Some Car-stereos have car chassis ground potential on the speaker outputs and probably that causes the amplifier to shut down.

You can test the amplifier with a portable CD-player or MP3-player if your car stereo doesn´t provide RCA-outputs.

Ok, I hooked up my the CD player from my home's entertainment center to my ads amp and it works like a charm. So I will need to use a line level converter after all. Looks the NE-7V from David Navone will do the trick. Only problem now is during my 'test', I lost all presence of mind and managed to smoke my '03 Accord's stereo. It's embarrassing to admit, but I connected the output of the amp to the rear speakers without disconnecting the factory stereo. The factory stereo was off so I didn't give it a second thought. At first everything was fine and the next thing I know the factory stereo is smoked. Now I’ll have to by a replacement. I hadn’t planned on that. Anyone know where I can get a great deal on a new factory stereo for an ’03 Accord EX-V6 without Navigation?

ok now that I understand that we´re talking about a stock-stereo that would make sense that the amp turned off. Usually stock-stereos use car-chassis gnd for the speakers, too.

Hmmm, you will probably need to visit a forum about your car and ask people there if they drawings about how to get the stereo out off the dash board.

That´s why i like German/ Japanese cars. Those usually have DIN-stereos that can be taken out quite easily.
Ok, the factory stereo is in the repair shop. It looks like one of the chips in the amp section is fried. Should take only a about a week to get it back from the repair shop. Once I get it back I would like to connect an LOC from David Navone Engineering. But I have one doubt in my mind. If the amp shuts down when connecting speaker level inputs, and this is caused by this so called 'car chasis ground potential', then will this not also be passed through the LOC and prevent the amp from working?

BTW, this is on an '03 Accord. For some dumb reason Honda decided to opt for Non-DIN stereo in this version of the Accord.

I assume that is a converter you want to use. It depends on the way this thing is working. Usually there are two ways.

1: simple resistor / capacitor network
2: transformer

#1 is the cheapest version on setting down the speaker level to RCA level. This is the type that is usually built into amplifiers that have high-level inputs. Also cheaper High-Low converters work this way.

#2 better solution than #1. Here a special transformer seperates the speaker side from the RCA side. There is a wide variety of high-low adapters around. Some of them have high-quality transformers that will allow some quite good music quality. Cheaper ones will result in a lack of the higher and very low frequencies. The transformer has the advantage that it uses two coils, signals are transmitted by magnetic fields. So there is no direct connection between your amplifier and the stereo and this is what prevents the amp from shutting down.

Before you start looking around for a good high-low level converter I´d suggest to check your stock unit if it has a special ISO-connector. Some stock units offer RCA-level outputs but they dont have RCA-jacks . Ask the repair-shop guy if he can tell you if there is an ISO-plug that carries RCA-level outputs. Usually the ISO-plug that connects CD-changers and other stuff (e.g. telephone-mute , navigation-systems and other stuff) also carries the RCA-level outputs. You then just need an adapter from the ISO-plug to RCA jacks, I assume Radio-Shack [if this is still around- I haven´t been to the US for over 10 years now :( ] could provide those adapters.

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