Hissing and whistling in the STe audio output

[nokturnal]

@exxos: that's bad news, hoped to get one. Could you also add list of components to pcb thread? Resistors are decipherable from photos, but capacitors not. Thank you..

[exxos]

@exxos: that's bad news, hoped to get one. Could you also add list of components to pcb thread? Resistors are decipherable from photos, but capacitors not. Thank you..

They are in the BRD file..

There are only 2.2uF and 10K resistors anyway.

[Steve]

Just wanted to add that I installed the STe DAC noise PCB on a TT tonight, it certainly did reduce the whiney noise that was present. Not entirely removed of course. But a large percentage better.

Photo of installation:

PXL_20241222_141133933.jpg

[stween]

For the record: every single STE I've ever owned has had a very clear issue with noise, which is sometimes a little bit like listening to an old modem: you get used to the typical noises, and notice when something isn't right!

Still, I installed the beta audio fix into one of my STEs recently. I don't mind saying that I could not get the soldering method with the pins to work for me at all, so instead I chopped the legs off some spare LEDs and soldered those individually to the chips, and they were malleable enough that it was easy to then get the holes on the little fix board aligned and soldered.

For the sake of recording the impact, I tried to grab some audio out before the install and after under difference workloads (gembench, field diagnostics, Faster from FDD and HDD, and Gembench at 32MHz (via the exxos booster)

For the sake of recording the difference, here's before:



and here's after:

[exxos]

Cool. The original diagnostic cart test is crazy! Odd it only really starts beeping when it's hammering the display! I thought it was any access to RAM would cause the issue.. But seems much worse when it's changing the display.

[Steve]

Is it just me or is it actually quieter in 32mhz mode? :)

[BlankVector]

Still, I installed the beta audio fix into one of my STEs recently.

That's amazing! No more noise.
I have the very same issue in my STE: I can hear the data when it passes on the bus. I definitely should try that.

I don't mind saying that I could not get the soldering method with the pins to work for me at all

I would like to understand what you did precisely.
Your goal was to try the fix presented at the very top of this thread, right?
And instead of using some wires, you just used spare LEDs legs, as it's equivalent?

[exxos]

I just realised @stween posted in the wrong thread... It should actually be this thread.. viewtopic.php?t=643

Both fixes were better documented on my website

https://www.exxosforum.co.uk/atari/last ... /index.htm

[stween]

I just realised @stween posted in the wrong thread... It should actually be this thread.. viewtopic.php?t=643

My bad; I searched and I guess I saw the prior post about the audio fix in a TT. Can you or a mod move the posts?

[exxos]

My bad; I searched and I guess I saw the prior post about the audio fix in a TT. Can you or a mod move the posts?

Yep posts moved.