I'm stumped.

[PierreB9]

Far from being a newbie, but this has me feeling like one. Connecting a projector's audio to an amp.

This is the current, working set-up. Using two 3 ft stereo cables, 1/8th males and a few adapters to reach the amp's 1/4" mic input. From the projector's audio out, to a female 1/8th which is split to 2 RCA males. These go into a similar adapter with two RCA females merging to a 1/8th female into which the second cable goes and is fitted with a 1/8 to 1/4 adapter.

Then I got tired of fidling aroud each time I need one of the adapters and the cables were barely long enough so I got a long one with a 1/4" at one end and a 1/8 at the other. Problem solved? You would think so, but all I get is white noise. The cable is fine, I tried it in 2 diferent connections, one on my pc and one in a digital piano. worked fine.

Then I put my wiring jig back in and it's quiet as a mouse.

Whats the deal? I'm at a loss to explain it.

 

[Blumlein 88]

You wouldn't want to use a mic input. Maybe that isn't what you mean. Maybe give the projector model and the model of the amp you are using would let us be of more help to you.

And welcome to ASR as this looks like your first post.

 

[PierreB9]

You wouldn't want to use a mic input. Maybe that isn't what you mean. Maybe give the projector model and the model of the amp you are using would let us be of more help to you.

And welcome to ASR as this looks like your first post.

Thanks. The projector is a ViewSonic, and the amp is an obscure Chinese kareoke Monkey brand. Normally, I would use a Line input, but the one its got is very weak; but the mic input is stereo and hot. It's surprisingly pretty noiseless, and sounds fine in my super Sony headphones, The problem lies entirely on the cables. Why is the new, strait line cable not working but the patched together one is? I tried fooling it by switching the RCA white into red, didn't even notice the channel switch. I could get another cable but its working fine elsewhere. I can hear the signal coming through very faintly, but the noise is coming from where?

 

[Blumlein 88]

Are you paying attention to TS and TRS type connectors. Hard to follow your exact connection with all the adapters. I wonder if you perhaps don't have quite the connection you think with the cabling that does not work. If you have a multimeter checking the continuity for a connection between one end of the cable and the other end with all adapters in place might help you figure that out.

In this example the size isn't important, simply that TS has two connections and TRS has three. Sometimes going from a pair of stereo adapters to a single one that should have 3 connections you can trip yourself up somewhere along the way.

 

[Deleted member 48726]

Are you paying attention to TS and TRS type connectors. Hard to follow your exact connection with all the adapters. I wonder if you perhaps don't have quite the connection you think with the cabling that does not work. If you have a multimeter checking the continuity for a connection between one end of the cable and the other end with all adapters in place might help you figure that out.

In this example the size isn't important, simply that TS has two connections and TRS has three. Sometimes going from a pair of stereo adapters to a single one that should have 3 connections you can trip yourself up somewhere along the way.
View attachment 312099

That's a good clue. I would follow that route as well.