LisaList2

General Category => LisaList2 => Topic started by: nekonoko on November 03, 2023, 11:35:21 am

Title: LisaDAC in 2/5, Any Experience?
Post by: nekonoko on November 03, 2023, 11:35:21 am
I have a Lisa 2/5 with a VintageMicros DAC card installed. In my system the card does operate, but seems overly loud and distorted with persistent hum/background noise once initialized.

I was wondering if this is just how these cards are or if there is a slight incompatibility  - perhaps the VIA clock difference between 2/5 and 2/10 I/O boards or an improper resistor value (or other defect). Not having encountered another of these I have a sample size of one to compare it with.
Title: Re: LisaDAC in 2/5, Any Experience?
Post by: sigma7 on November 04, 2023, 02:32:24 pm
DAC card ... seems overly loud and distorted

IIRC, the distortion is common for a lot of the sound output, here is an example: YouTube: New DAC Sound Card for Apple Lisa (https://youtu.be/m0HV9PTQK8M?t=267)

The pixel tracks on the screen is an indication of incompatibility... those bits are supposed to go into sound hardware locations.

However, I believe there were a few applications that had good sound with it; I think Dafax published a list of those.

Earlier in the video there are some MacinTalk examples that have pretty good quality.

As for too loud, that may be a hardware problem which may be adding further distortion.
You could compare your board with the one shown here: LisaDAC Sound Card (https://lisalist2.com/index.php/topic,459.msg3286.html#msg3286)
Title: Re: LisaDAC in 2/5, Any Experience?
Post by: nekonoko on November 05, 2023, 01:38:35 am
That's exactly what I was looking for; mine sounds pretty much the same. I'll go over the board just to make certain but based on that video it seems to be expected behavior. Thanks for the info!