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Bill_Todd · 02-01-08, 06:45 AM

OK after a quick test I can confirm the stereo outs DO work while recording the mic input, i.e. you can hear the playback while laying down a new track. However, you cannot hear the track you're laying down (presumably to stop feedback while track laying).

I found the mic input switching to be a little tricky on my axim; I made a simple RCA phono to 4pole jack adapter for the test and found that I had to plug the adapter into the Axim before connecting the input to the phono, in order to get the Axim to switch to external mic input. I suspect the Axim senses the load on the mic power supply as the jack is inserted (the mic output sits at ~+3vdc in order to power electret mics capsules).

One thing you will need to do is add a considerable pad (attenuator) to the input; I measured a maximum input of just 20mVrms @ 1kHz ( ~-32dBV) on the input before it clipped.

[edit]
Inserting a 100n capacitor in line with the mic input fixed the switching problem.

Maximum output level appears to be around 220mVrms @1kHz so you might need an amplifier to lift the level into most monitoring equipement (see Aximiser thread for a suitable circuit)

[edit] correcting typo.

02-01-08, 06:45 AM	#7 (permalink)
Bill_Todd Aximsite Major League Join Date: Mar 2006 Posts: 309 Location: Colchester (nuked in 1984) PDA: Axim X51V iTrader Rating: (0) Thanks: 0 Thanked 6 Times in 2 Posts View MyPDA	OK after a quick test I can confirm the stereo outs DO work while recording the mic input, i.e. you can hear the playback while laying down a new track. However, you cannot hear the track you're laying down (presumably to stop feedback while track laying). I found the mic input switching to be a little tricky on my axim; I made a simple RCA phono to 4pole jack adapter for the test and found that I had to plug the adapter into the Axim before connecting the input to the phono, in order to get the Axim to switch to external mic input. I suspect the Axim senses the load on the mic power supply as the jack is inserted (the mic output sits at ~+3vdc in order to power electret mics capsules). One thing you will need to do is add a considerable pad (attenuator) to the input; I measured a maximum input of just 20mVrms @ 1kHz ( ~-32dBV) on the input before it clipped. [edit] Inserting a 100n capacitor in line with the mic input fixed the switching problem. Maximum output level appears to be around 220mVrms @1kHz so you might need an amplifier to lift the level into most monitoring equipement (see Aximiser thread for a suitable circuit) [edit] correcting typo. __________________ Bill Last edited by Bill_Todd : 02-10-08 at 08:50 AM.