Drew wrote:
On 2 Nov, 09:52, "Bill Buckels" <bbuck...@mts.net> wrote:"Toinet" <antoine.vig...@laposte.net> wrote:Will your board allow sound input as well as sound output? I mean "num�risation du son" (sound digitization)Hi Tony, That would be good if Drew's board provided recording as well as playback functionality. (i.e. ADC input as well as DAC output). BillHi, At the moment it will be output only. I have thought about input, and i 'might' look at this at a later date. This is all new to me and am keen to get something produced and then look at how i can improve things maybe on a version 2.0 board, but to be honest if i was going to do the input i would need lots of help from the group :).
Since the Ensoniq ADC input (mono) is on the same connector as the multiplexed outputs, you already have access to the input. All that's needed is suitable amplification for your intended input (required for a microphone input) plus an anti-aliasing low-pass filter--probably another two op-amps as active filters. The net impact to the bill of materials would be another two or three op-amps (in one chip), about a dozen passives (resistors and capacitors), and an input jack--plus a gain control if one is not available off-card. If a low-level (microphone) input is provided, some care should be exercised in laying out the card to avoid noise pickup. -michael NadaNet 3.0 for Apple II parallel computing! Home page: http://home.comcast.net/~mjmahon/ "The wastebasket is our most important design tool--and it's seriously underused."