DAC sound on some tracks has distortion...

[Braincell1973]

Hi,
Using the dual PWM & DAC firmware 0.14 i have noticed some tracks have distortion......

But on PWM output on the same dual firmware the sound is superb.......

https://youtu.be/HWDtWiZlBCA?si=cKPHV06s_XPNz3uW

This should help diagnose....

Lee

[frntc]

This sounds as if Phi2-clock and that what the SKpico expects differ (DAC scratchy, PWM fine). I assume PAL/NTSC is set correctly in the config tool? Can you measure Phi2 in your machine?

[modeler]

I tried the tune in question (https://hvsc.csdb.dk/MUSICIANS/M/Mitch_and_Dane/Dane/Seeress_Foretold_My_Future.sid) through the DAC audio on my short board C64C (0.14 DAC only, SKpico_DAC_LED.uf2) and it sounds perfect, no distortion at all.

[Braincell1973]

I'm using the combined DAC + PWM on a c128. Pwm is perfect, DAC is distorted...... weird Other tracks great on DAC ??? Weird distortion is evident on my video I linked but I'm away with work this week so can't do anything till I return. I will try another SK pico in one of my c64s, good to know the dac only works ok, DAN , are you able to try the pwm and dac firmware on your board? Lee Sent from Outlook for Android<https://aka.ms/AAb9ysg>

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________________________________ From: Daniel Tootill ***@***.***> Sent: Saturday, April 20, 2024 11:49:19 PM To: frntc/SIDKick-pico ***@***.***> Cc: Braincell1973 ***@***.***>; Author ***@***.***> Subject: Re: [frntc/SIDKick-pico] DAC sound on some tracks has distortion... (Issue #41) I tried the tune in question (https://hvsc.csdb.dk/MUSICIANS/M/Mitch_and_Dane/Dane/Seeress_Foretold_My_Future.sid) through the DAC audio on my short board C64C (0.14 DAC only, SKpico_DAC_LED.uf2) and it sounds perfect, no distortion at all. — Reply to this email directly, view it on GitHub<#41 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AG62KOQCDYI7WOJEGR4QQQTY6LWG7AVCNFSM6AAAAABGGDKHWWVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDANRXHAYDOMBVGM>. You are receiving this because you authored the thread.Message ID: ***@***.***>

[modeler]

I will try another SK pico in one of my c64s, good to know the dac only works ok, DAN , are you able to try the pwm and dac firmware on your board?

I tried it with the SKpico_v014/SKpico_DAC_PWM.uf2 firmware and it plays fine:

https://youtu.be/bZhRAtnbOvU

I do have a C128 myself though, will dig it out and see if I mine behaves the same.

[modeler]

@Braincell1973 I was able to test the DAC firmware with my C128 today and the tune played fine (as a PSID executable, attached). Sorry for the delay, the darn thing had a bad RAM chip so had to repair that first!

I wonder if it is the demo itself that is causing the issue? I have seen one case where the audio in a demo is distorted with SKP (PWM and DAC), yet it plays as a stand-alone PRG quite happily. Might be worth you trying this tune on its own on your machine?

https://drive.google.com/file/d/1FNEtHFiG0NaTitvadJIvSaTmRiaBG085/view?usp=sharing

[modeler]

Listening to a long SID tune via the DAC output, I somehow managed to hear the same sort of distortion. It crept in after about eight minutes and swamped the audio with white noise on all tunes. I had to power cycle the C64 to clear it. Haven't been able to reproduce it since, so not sure if the problem is related or just an anomaly.

[Braincell1973]

I have been working away so have been unable to test further, will do after this weekend Sent from Outlook for Android<https://aka.ms/AAb9ysg>

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________________________________ From: Daniel Tootill ***@***.***> Sent: Friday, May 10, 2024 10:53:44 AM To: frntc/SIDKick-pico ***@***.***> Cc: Braincell1973 ***@***.***>; Mention ***@***.***> Subject: Re: [frntc/SIDKick-pico] DAC sound on some tracks has distortion... (Issue #41) Listening to a long SID tune via the DAC output, I somehow managed to hear the same sort of distortion. It crept in after about eight minutes and swamped the audio with white noise on all tunes. I had to power cycle the C64 to clear it. Haven't been able to reproduce it since, so not sure if the problem is related or just an anomaly. — Reply to this email directly, view it on GitHub<#41 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AG62KOREWHVCA4A5PR62MDLZBSKKRAVCNFSM6AAAAABGGDKHWWVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDCMBUGMYTANJWGM>. You are receiving this because you were mentioned.Message ID: ***@***.***>