Download vs. Re-recording?

[JesusFreak1959]

New-b here.  Recently hired to do sound design for a LBE site where both the AP-8 and AP-16 are employed.  The dox spell out that the only way to get audio into the cards is to re-record.  Since this process causes a decrease in fidelity (huge on the AP-8), is there any way to download the files since there is communication between PC & AP card?  Bossman is complaining about the intelligibility of audio created previous to my tenure.  I have all kinds of tools available to me from my 20 years of doing sound design for computer games... especially from the 8 bit days in the 90's.  But it is all for naught if the only method for getting audio into an EFX-TEK card is by recording.  Any wisdom from my fellow audio geeks?

[JonnyMac]

The only way to get audio into the AP-8 is to play it into the AP-8 while the AP-8 is in record mode; it's the limit of the ISD technology (i.e., there are no programmers available that let one transfer the audio into it using a digital format).  What you'll want to do is setup a test with your system so that you can normalize you audio to a known level (I use -0.5dB), then set your PC volume to the point that gives you the best recording on the AP-8.  It may take a few tries to determine the best volume setting for your PC.  For heavily dynamic sounds you may want to use a bit more compression than normal.

The AP-16+, on the other hand, makes life easy.  Simply create 16-bit, PCM encoded, stereo WAV files and drop them onto the SD card.  That's it.

[JesusFreak1959]

The only way to get audio into the AP-8 is to play it into the AP-8 while the AP-8 is in record mode; it's the limit of the ISD technology (i.e., there are no programmers available that let one transfer the audio into it using a digital format).  What you'll want to do is setup a test with your system so that you can normalize you audio to a known level (I use -0.5dB), then set your PC volume to the point that gives you the best recording on the AP-8.  It may take a few tries to determine the best volume setting for your PC.  For heavily dynamic sounds you may want to use a bit more compression than normal.

The AP-16+, on the other hand, makes life easy.  Simply create 16-bit, PCM encoded, stereo WAV files and drop them onto the SD card.  That's it.

Thanks for the response JM.  OK, so the new AP-16 is the way to go, but the bossman has a huge (did I say "huge?") investment in AP-8's that won't will be dumped in the river any time soon.  Which causes me to probe further.  You say "...there are no programmers available that let one xfer the audio into it using a digital format."  Is this a matter of someone writing some scripts (because I used to write low-level code back in the day), or is does this imply someone back at the factory that needs to modify firmware on a chip/chipset?[/i]

[JonnyMac]

No, it's a hardware issue.  Think of the ISD device as tape on a chip; it uses analog storage cells to hold the audio and there is no digital path in.

Now... Winbond may have some device that it uses for high-end production runs, but I know of no such device for the rest of us.  And if creating one was a matter of programming, we would have done it a long time ago.  The process of getting audio into ISD chips is not fun which is why we don't use them any more (okay, one of many reasons).

Since your boss has a huge investment in AP-8s it would then make sense for you to set some "standards" for the particulars of your system.  As I told you, I normalize to -0.5dB and I know where to set my master volume control to get the best audio.  You'll have to make a few recordings to see what level gives you the best SNR without distortion.

[JonnyMac]

And, finally, the ISD2500 that we used in the AP-8 is no longer in production and not supported by Winbond.  Heck, they don't support their current line very well either (which is why the ISD-based version of the ISD never saw the light of day beyond the prototypes that John and I have).

The message: normalize to a standard that you think best and determine the audio levels from your PC to get the best sound out of the AP-8.  There's not going to be any short-cut for getting audio in.