maybe variable resistor is dirty or capacitor on ne555 is aged.
Replacing them should fix it

if you have a scope check output frequency of NE555 it should be around 7Khz

matze79 wrote on 2021-12-18, 20:22:

maybe variable resistor is dirty or capacitor on ne555 is aged.
Replacing them should fix it

if you have a scope check output frequency of NE555 it should be around 7Khz

Thanks for the respond! Here are the internals Re: Disney Sound Source Pinout
Which capacitor is the suspect?
Don't have a scope, unfortunately.

Ah sorry i was thinking about clone.
Normal dss has no ne555.

Well I would first start with cleaning the VR. Spill it with isopropyl alcohol and turn it bit forward and back.

Disney Sound Source Pinout

Can you see the small foil capacitor (green) maybe it is the issue here ?

Please try a different game which has native dss Support.
Does it also happen in niteraid or hocus pocus?

matze79 wrote on 2021-12-19, 11:10:

Well I would first start with cleaning the VR. Spill it with isopropyl alcohol and turn it bit forward and back.

One could also try to connect a resistor in parallel using test leads. If that makes a difference, the variable resistor needs to be cleaned or replaced.

matze79 wrote on 2021-12-19, 11:10:

Ah sorry i was thinking about clone. Normal dss has no ne555. […]
Show full quote

Ah sorry i was thinking about clone.
Normal dss has no ne555.

Well I would first start with cleaning the VR. Spill it with isopropyl alcohol and turn it bit forward and back.

Disney Sound Source Pinout

Can you see the small foil capacitor (green) maybe it is the issue here ?

Please try a different game which has native dss Support.
Does it also happen in niteraid or hocus pocus?

I've tried also Wolf3D that has DSS native support - same thinng. Will try Hocus Pocus too.
I'll start with cleaning the resistor. Hope the solution is that simple.
DSS has the ICS1493 clock synthesizer that generates 22.5792 MHz clock. I assume it's divided somehow by 3 to get the 7,something clock that DSS is working on. I'm not really into electronics, but can this "division" be issue? How is it done (if at all)?

And can the problem be on the amplifier side?

Benedikt wrote on 2021-12-19, 14:09:

matze79 wrote on 2021-12-19, 11:10:

Well I would first start with cleaning the VR. Spill it with isopropyl alcohol and turn it bit forward and back.

One could also try to connect a resistor in parallel using test leads. If that makes a difference, the variable resistor needs to be cleaned or replaced.

Thank you for the suggestion. Will try that as well.

The Datasheet you read is for different IC they simply have same Name.
Its no way a ICS1493, this is SMD Chip and much more modern.
It did not even exist back then 😀

Its a Custom ASIC.

No the Amplifer Box ist just LM386 Amp, it can`t change speed.

It must be the VR or a Capacitor.
It could be the foil capacitor is aging for example.
Not sure what its purpose is, so i only can guess.

The thing uses a simple RC oscillator for its timebase and that film capacitor + potentiometer are for controlling the oscillation speed. If the pot doesn't make a difference it is surely misbehaving, but if it does change the pitch but not enough it might be the capacitor gone significantly out of spec.

So, yes, it was the potentiometer. Just cleaning did not help as It was way out of the specified 200k. After long fiddling i managed to lower the resistence to about 85k and the sound is almost correct now. Will replace it it at some point.
Thanks to everyone for your help!

Not exactly on-topic, but my cat also had big issues with the sound sample in OP, where she normally snoozes happily through Doom. Perhaps I should use her more for diagnostics of sound issues.

dionb wrote on 2021-12-21, 22:08:

Not exactly on-topic, but my cat also had big issues with the sound sample in OP, where she normally snoozes happily through Doom. Perhaps I should use her more for diagnostics of sound issues.

Haha, I have my son in the role of your cat. He called the DSS distorted samples, pardon, "rectal sounds"

haha 😀 nice it works.

Hello,
may I ask how it's possible to play DOOM sounds on a DSS? Thank you!

Scandy wrote on 2022-05-06, 18:14:

Hello,
may I ask how it's possible to play DOOM sounds on a DSS? Thank you!

FastDoom mod has DSS support FastDoom. A new Doom port for DOS, optimized to be as fast as possible for 386/486 personal computers!

So the sample recording in your first post is from FastDoom? Thank you so much for your kind feedback.

Scandy wrote on 2022-05-06, 20:44:

So the sample recording in your first post is from FastDoom? Thank you so much for your kind feedback.

You're welcome. Yes, the sample is from FastDoom.