R
Rutus
For those of you who may be running music inputs to your Flightcom 403 intercom, here is what I did.
First, after reviewing several threads on music interfaces, I went ahead and fab'd up an impedance matching transformer assembly (per George's excellent posts on this), using about $12 worth of Radio Shack parts. The 2 (L&R) aux. music input wires from the 403 and a ground wire from my audio ground (forest of Fast-Ons on the firewall, per 'Lectric Bob) were connected to the high impedance side, and then the low impedance (8 ohm) side was connected to a 3 terminal panel mount 1/8" jack (L, R, and audio common).
Using a standard 3 conductor 1/8" audio cable (L, R and common) with male plugs at each end, I would get audio in only one channel on the headset. From switching leads it was clear that the problem was not with the intercom side of things. Then, I tried using a patch cable that came with my Lightspeed 20XL headsets, which have a music input on the battery box. This is an oddball cable that appears to have a four-conductor configuration on the end that goes into the Lightspeed battery box - or, in this case, into my panel jack - and a regular three conductor pin to go to the IPOD.
Voila! Clear audio in both L and R sides of the headsets. But, not as loud as I might like.
So, to experiment some more - I deleted the impedance matching transformer, and just ran the Flightcom aux music leads (L&R) to the panel jack, and the third tab on the panel jack (audio common) went to the audio ground at the firewall, as before. Now, using the Lightspeed patch cable, I get good quality stereo with much better volume and no apparent loss in audio quality. Sound quality is a little better in my Lightspeeds, on the other hand my Halos are a bit louder.
Oddly, the Flightcom installation instructions seem to show the impedance matching transformer, but in my case it did not seem to help audio volume or quality at all, and in fact reduced the maximum volume noticeably.
I would be interested in hearing from others using this intercom with an IPOD or similar device, and how you wired it up. I am still puzzled at the need for the oddball patch cable - whatever it is, it works.
First, after reviewing several threads on music interfaces, I went ahead and fab'd up an impedance matching transformer assembly (per George's excellent posts on this), using about $12 worth of Radio Shack parts. The 2 (L&R) aux. music input wires from the 403 and a ground wire from my audio ground (forest of Fast-Ons on the firewall, per 'Lectric Bob) were connected to the high impedance side, and then the low impedance (8 ohm) side was connected to a 3 terminal panel mount 1/8" jack (L, R, and audio common).
Using a standard 3 conductor 1/8" audio cable (L, R and common) with male plugs at each end, I would get audio in only one channel on the headset. From switching leads it was clear that the problem was not with the intercom side of things. Then, I tried using a patch cable that came with my Lightspeed 20XL headsets, which have a music input on the battery box. This is an oddball cable that appears to have a four-conductor configuration on the end that goes into the Lightspeed battery box - or, in this case, into my panel jack - and a regular three conductor pin to go to the IPOD.
Voila! Clear audio in both L and R sides of the headsets. But, not as loud as I might like.
So, to experiment some more - I deleted the impedance matching transformer, and just ran the Flightcom aux music leads (L&R) to the panel jack, and the third tab on the panel jack (audio common) went to the audio ground at the firewall, as before. Now, using the Lightspeed patch cable, I get good quality stereo with much better volume and no apparent loss in audio quality. Sound quality is a little better in my Lightspeeds, on the other hand my Halos are a bit louder.
Oddly, the Flightcom installation instructions seem to show the impedance matching transformer, but in my case it did not seem to help audio volume or quality at all, and in fact reduced the maximum volume noticeably.
I would be interested in hearing from others using this intercom with an IPOD or similar device, and how you wired it up. I am still puzzled at the need for the oddball patch cable - whatever it is, it works.
