Increek,
In another machine that I built, I wanted a front headphone jack that would mute the speakers that are connected to the audio-out jack on my soundcard. I followed these instructions (
http://www.pc-workshop.net/submit/minor/phaestus.shtml), except that I took a shortcut and cut a 1/8? (3.5mm) headphone extension cable and soldered it to the 5-pin closed-circuit headphone jack.
In this case, what I plan to do with my case is to put the 5-pin (closed-circuit) headphone jack on the front panel and a standard 1/8? stereo headphone jack (open-circuit) on the rear panel. Plugging headphones into the front jack will disconnect my speakers that are connected to the rear jack. On the Radio Shack (#274-246) packaging for the 5-pin headphone jack there is a wiring diagram on the back. The pin assignment is as follows (I may have the left and right mixed up):
Pin Use
---- ------------------
1 ---------- Ground
2 ---------- Source (L)
3 ---------- Switched (L)
4 ---------- Switched ( R)
5 ---------- Source ( R)
If you use this 5-pin jack, I think that you have two choices for a second audio-out jack: 1) solder a jack to the motherboard as described earlier in this thread or 2) connect directly to the closed-circuit front headphone jack.
I haven?t tested this, but here is how I would connect lead wires for each situation:
1) with rear audio jack soldered to motherboard:
Header J7 Radio shack 274-246
-------------- ----------------------------
1 (Ground) ---------- 1 (Ground)
5 (SPKROUT R) ----- 2 (Source R)
6 (Return R) -------- 3 (Switch R)
8 (Return L) -------- 4 (Switch L)
7 (SPKROUT L) ----- 5 (Source L)
When the front headphone jack is empty, the rear jack will be active ? in effect, the front jack is jumpering pin pairs 5 & 6 and 7 & 8, as suggested on p 35 in the motherboard manual.
2) second headphone jack (open-circuit) not soldered to the motherboard ? this concept follows the work done by Phaestus in the mod link above:
Header J7 Radio shack 274-246 Open circuit headphone jack
-------------- ---------------------------- --------------------------------------
1 (Ground) ---------- 1 (Ground) ----------------------- Ground
5 (SPKROUT R) ----- 2 (Source R)
6 (n/c) xxxxxxxxxxx 3 (Switch R) --------------------- Right
8 (n/c) xxxxxxxxxxx 4 (Switch L) --------------------- Left
7 (SPKROUT L) ----- 5 (Source L)
In this case, pins 6 & 8 (rear or return pair) on header J7 aren?t used since the switching path goes directly to the second jack. This is speculation on my part since I don?t think that anyone has established that a jack connected to J7 pins 1, 5 & 7 for certain works for audio-out. I am working strictly from the ECS pin-out drawing and some Intel front panel audio header design documentation (
http://www.formfactors.org/developer/fpio_design_guideline.pdf).
If connecting J7 pins 1, 5 & 7 (ground, right, left) to a simple 1/8? stereo headphone jack does, in fact, work, that might be a fairly simple solution to implement for those who don?t want to solder to the motherboard.