Talk to Yamaha!

Peter

Steve Demming is Yamaha...correct?

You guys are driving me nuts--I'll let you know in five minutes.

Gary

Hey Donny,

I know just what you need....Another image.

I gave some thought to UD's comment and did a little reading.....I'm tending to agree with him. Your input jacks on your keyboard are probably mono. They might be balanced (that's what the single-click, double-click test might have answered) but they're probably mono. Although in all fairness, we wouldn't really know without seeing a schematic (or hearing from Steve Demming).

Here's another image to look at:



This is a schematic of a balanced, mono, input channel in your average mixer. Notice the Line In jack right below the Mic jack. This is a balanced jack (positive phase of the audio signal = tip, negative phase of the audio signal = ring, and ground = sleeve) going to a differential amplifier (the first triangle)(the audio signal flows left to right). Notice the output of this device...One channel, mono (single-ended). From there the signal goes through the sub-bass filter, then the 3-band EQ circuits, then the next stage of amplification, the gain stage, then what?....The PAN pot. This is where they split the mono signal, sending equal parts to the final output stages (left and right)(depending on where you have your POT knob set, of course). So you see, this is not true stereo...I'll call it "pseudo stereo". Having a balanced input connector and using a balanced cable does not automatically mean you've got true stereo. It all depends on how they designed the circuitry.

If this schematic does reflect the circuitry in the keyboard, then true stereo would require you to connect the left channel of your input to one jack (1) and setting the pan pot to full left, connecting the right channel of your input to the other jack (2) and setting the pan pot to full right.

I take back my statement about the GeneralMusic WK8's input jacks being stereo. They're mono. Thanks Dave!

mike

OK, here's the deal. The jack itself is a stereo jack, however, the input is set up for mono. It's not a ballanced input--it's just a stereo jack wired with a mono hook-up. Kind of a weird way to do things, and I sure don't know why Yamaha did this, but I tried every wiring configuration and then went to my stereo mixer, fired a mic through it, connected both outputs through a stereo jack (In/out effects cable) and the best I can come up with is mono--not stereo. Sure would like to see a schematic of the board, but unless there's something wrong with my boards, I usually don't take them apart. If anyone has an up to date schematic, I would sure like to see it.

Cheers,

Gary

Mike ,


thanx for the excellent illustration.
Now Im on my 3rd Excedrin :>)

Gary,

Thanx so much for trying to get an answer....oh man what did I start?

Gary, you've confirmed what I said - it looks just like the 740. A stereo jack using tip and sleeve with the ring going nowhere.

Bryan

Dave is right.. mono will always be mono..you can split the signal, but it will still be two mono and not stereo..

Mike your one illustration is right out of the Mackie manual..right?