I'm looking to build or buy a device capable of mixing audio between a telephone handset, and a computer headset. The basic idea would be to control the source/destination/volume of the various audio signal inputs/outputs, allowing any audio input/output to be mixed together.

My main goal would be able to be wearing a computer headset, listening to music on my PC, pick up a phone call, and talk and listen to the phone call through my computer headset. I would want the option to keep my music playing while on the phone call, or to mute the computer audio for the duration of the call. In case I don't have my computer headset handy, I'd like to use the phone handset to receive or make a phone call.

It would be nice to allow the computer audio output to send to the phone Mic (so that computer audio could be played onto a phone call), or for phone audio to be sent to the computer via a line in, but that would just be an added bonus.

I am by no means seasoned in circuit design, but I have done basic circuit soldiering and such. I'm very willing to learn, but I think I'll need some help in the way of being pointed in the right direction to get this done. I have no idea if the below is feasible, but I imagine it to be a good start.


I'd like to be able to select any source or destination in the following manner:

Button Layout
-------------

Phone Mic = PM
Headset Mic = HM
Pushbutton = x
Volume Knob = *

Source

|----|----|
| PM | HM |
|----|----|
| x* | x* | Computer Mic Input
|----|----|
| x* | x* | Phone Mic Input
|----|----| Destination


Computer Audio Output (Stero) = CA
Phone Audio Output (Mono) = PA
Pushbutton = x
Volume Knob = *


Source

|----|----|
| CA | PA |
|----|----|
| x* | x* | Computer Headphones
|----|----|
| x* | x* | Phone Handset Speaker
|----|----| Destination



Connectors
----------

To Computer:

1/8 TS (phone jack) Mic Out
1/8 TRS (phone jack) Stero Output ** For Line In **

From Computer:

1/8 TRS (phone jack) Stero Output

To Computer Headset:

1/8 TRS (phone jack) Stero Output

From Computer Headset:

1/8 TS (phone jack) Mic In

To Telephone Handset:

4P4C (RJ9) Mic In & Mono Output

To Telephone:

4P4C (RJ9) Mic Out & Mono Input





All comments are welcome, even those calling me a crazy fool for wanting such a device...

not crazy...is a good idea.....might even be marketable

*bump*

Blast from the past. Just got pinged via PM on this today. Figured it might be worthy of a bump in the hopes of some fresh views, and possible replies.