Quote Originally Posted by pgeorgejuun
My brother gave me his old Technics SL-D3 turntable. I just bought some records to play on it and plugged the RCAs hanging out of the back of it into my little desktop stereo's rca aux input. The stereo is an Aiwa XR-X7. I have used the aux inputs with other external audio equipment, so i'm sure they work fine. When i plug in the SL-D3 though, i can only BARELY hear anything coming out of the speakers. Turning the stereo volume to its max setting is still miles away from normal -- actually still miles away from a whisper. It's only slightly louder than the natural sound that comes directly off the vinyl when you put your ear close enough to it.

Anyway, i looked in the Aiwa owner's manual and the aux input spec says "400 mV" and who knows what the output level is like on this turntable. My brother used this thing a lot, so i know it's working properly.

What am i missing here?

Thanks.

- Philip
As others have pointed out, your Aiwa seems to be functioning normally, it just doesn't have a phono input. A lot of equipment nowadays doesn't have one. You need a phono preamp, either one built in to a receiver, integrated amp or preamp, or else a separate one. Radio Shack sells an inexpensive one, I think, and for your purposes it would probably do OK, although for high fidelity purposes I understand it has a poor signal to noise ratio.

A phono cartridge's output is measured in millivolts, way under 400 mv! The output of a tape deck or CD player is measured in volts. As well, since dragging record grove past a phono stylus is an inherently noisy process, the highs are boosted on the LP record. For playback, the highs are cut down drastically and this will also reduce the high frequency noise from the record. The result for the music should be an approximately flat frequency response. A phono preamp therefore has two functions: 1) to raise the signal from the phono cartridge up to line level like a tape deck produces, and 2) to reduce the highs coming from the cartridge so the music will sound nice instead of sort of squeaky.