My wonderful wife gave me a beautifully reconditioned Marantz 2240 receiver. I'd like to use it as my phono stage. I have my turntable plugged into the phono in. Instead of the jumpers between the "pre outs" and "main in", I am running a Y cable from each preout. One pair from there goes to a line level input on my AVR. The other pair from there goes back to the "main in" on the Marantz (to amplify the headphone output).
Here is the problem. The left channel when on phono input is barely audible, whether using headphones or through the AVR. Switching the red and white RCA's on the phono inputs on the Marantz does not affect it -- the left channel stays quiet. If I press the mono button on the Marantz both channels play at equal levels, but obviously not in stereo. The tuner works fine in stereo and plays both channels.
Not sure what's up. Any ideas?
When you write 'reconditioned', does that mean it was cleaned and serviced, or cleaned and listened to? As electronic devices age, the controls and switches oxidize and one of the most common symptoms is losing one channel, or both in one or more inputs.
While the problem is only exhibited using the Phono preamp now, the rest of what's below pertains to any/all inputs. If the Marantz has a switch that separates the preamp and power amp, move that a few times to see if the problem stops.
Rotate the source selector quickly through its range while you play an album and see if it A) crackles or B) comes back to normal. If nothing changes, rotate all of the other controls and listen for a scratching sound that comes and goes with movement. If that doesn't change anything, start pressing all of the switches and listen for the same sound. Be careful with the volume control- the sound may come back when the level is high and that could damage speakers.
If you have a 3.5mm-stereo RCA cable & a smart phone or any other device that plays music and has a volume control, use that as your source and lower the volume so it won't be too loud even at maximum on the Marantz volume control. When you connect it to the Phono input, turn the bass down fully- the phono preamp boosts the bass immensely and this can damage speakers if you leave it above minimum and increase the volume level. Use soft music without heavy bass for these tests.
If this does help, you or someone else will need to clean the controls and switches. Caig is the brand many use and it does work well. Radio Shack sells it but if you don't have one of their stores near you, Parts Express sells it, too.