Sound issues

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orion70
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Sound issues

Post by orion70 »

I recently found time to count and fire up all my VICs. Most of them are working. Two are made with "pure" components (i.e., not cannibalized from other machines); but four out of six working babies are real Frankensteins, with creative mixes between motherboard, chassis, and keyboard. The latter group include my beloved one, with a really old two-prong PAL mobo in a paper label chassis (not matching) and a first issue PET style keyboard (again, not matching). The original PET style machine was a US NTSC VIC with a two-prong female connector not compatible with the one I have (from UK), and a poorly preserved chassis.

Three more VICs have issues. Two of them show major issues, but I haven't tested them with Tynemouth Software's VIC Diagnostics yet, so I don't really know what's going on there.

And this brings us to the third one. I'm sure it worked until a year ago or so, but now it presents with a really strange issue. It loads and runs well every game and program regardless of the RAM required, with all my SD2IEC devices. Also, Tynemouth's hardware gives a PASS to all tests. But the sound is either weird (completely off-key) or totally absent. Two examples: Popeye plays a horrible intro tune, reminding my attempts to imitate Frank Sinatra 8), and Radar Rat Race plays only sound effects (eating the cheese, dying, etc.) but no Three Blind Mice at all.

What can it be? If someone could point me to a possible culprit, I'd use chips from the other two motherboards, hoping they still work. TIA.
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beamrider
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Re: Sound issues

Post by beamrider »

Sounds like the Vic chip?

A number of my machines have started failing this year. Must be as vics approach 40 years old..
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R'zo
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Re: Sound issues

Post by R'zo »

With loading issues could it be a via issue? The music wouldn't sound right if the data wasn't loaded correctly.
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beamrider
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Re: Sound issues

Post by beamrider »

R'zo wrote:With loading issues could it be a via issue? The music wouldn't sound right if the data wasn't loaded correctly.
Wouldn't it be more likely to just crash though?

.. and unless Radar Rat Race was loaded from tape/disk, kinda rules this out.
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R'zo
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Re: Sound issues

Post by R'zo »

beamrider wrote:
R'zo wrote:With loading issues could it be a via issue? The music wouldn't sound right if the data wasn't loaded correctly.
Wouldn't it be more likely to just crash though?

.. and unless Radar Rat Race was loaded from tape/disk, kinda rules this out.
Good point.

It seems odd to me that the audio issues are different with each program. Depending on the voices being used. Say if blind mice uses only voices 36874 and 36875, rat race uses 36874 and 36875 for music and 36876 and 36877for effect and Popeye used all 4 voices. If this were the case I could see it being the vic. If it were the case of certain voices not working though the remaining voices should still harmonize.
Could this be caused by something in control of timing or possibly interupt controls?

orion70
I'm curious if you've tested each game multiple times, are the sound issues consistant?
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orion70
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Re: Sound issues

Post by orion70 »

beamrider wrote:
R'zo wrote:With loading issues could it be a via issue? The music wouldn't sound right if the data wasn't loaded correctly.
Wouldn't it be more likely to just crash though?

.. and unless Radar Rat Race was loaded from tape/disk, kinda rules this out.
Loaded RRR from SD2IEC, in fact (via Final Expansion). I was extensively testing all my machines, and had only a couple of hours at my disposal...
R'zo wrote:orion70
I'm curious if you've tested each game multiple times, are the sound issues consistant?
...so no, I didn't test the games mutiple times. I only loaded four of them, once each: Popeye (32K) played weird; Radar Rat Race (8k ROM) no tune but with sound effects; Air Attack (from an Italian mag, unexpanded, it has only simple sound effects) played OK; and Gorf (8k ROM) with weird sounds. I will dig deeper whenever I find the next spacetime wormhole and escape family for a while :).

I'll check these games again, and load something more (Boray's music, or fire up the Mega-Cart and play backgroung music). Then, upon persisting issues, I'll try and swap the VIC chip with the other failing mobo (hoping it's intact).
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beamrider
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Re: Sound issues

Post by beamrider »

If you have the mega-cart then you can of course compare the radar rat race on their too..
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R'zo
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Re: Sound issues

Post by R'zo »

If sound issues end up being different depending on expansion required that would seem to me to point towards addressing issues. This would also depends on where audio data is being stored. If music data for cerain programs is stored in expansion then it could even be bad expansion or even bad or dirty pins in the expansion port.

I would personally start by writing poke commands directly into basic (that would help count out connectors or expansion) poking each channel one at a time (make sure you poke the sound on first :). If you poke 36874 with a value between 128 and 255 and you get no sound then you know the voice is not working and you most likely have a bad chip.

If all voices are making noise then you get a tuner and test each voice out poking various pitches. If all voices are relatively accurate in pitch then your problem is more
Iikely elsewhere. This to me would be the simplest way to test your issue without opening anything up.
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orion70
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Re: Sound issues

Post by orion70 »

Here I am, in a lazy hot summer afternoon, with an hour to dedicate to my beloved machines.
beamrider wrote:If you have the mega-cart then you can of course compare the radar rat race on their too..
Loading RRR via original cart or MC gives a perfectly working game. BUT turning the VIC on with the MC plugged in gives a strange garbage screen for a couple of seconds, with a high-pitch tune, then loads the correct start menu with COMPLETELY WRONG BACKGROUND MUSIC! I went to the music selection menu of the MC, and tried all tunes. After a minute or so of cacophonous music, the system hangs (in the selection menu, but not in the main menu!), and I have to reset it. Note that music and sound effects in games from the MC are perfectly OK.
R'zo wrote:I would personally start by writing poke commands directly into basic (that would help count out connectors or expansion) poking each channel one at a time (make sure you poke the sound on first :). If you poke 36874 with a value between 128 and 255 and you get no sound then you know the voice is not working and you most likely have a bad chip.
All sound pokes work flawlessly (74, 74, 76, and 77). No strange tunes or variations in time.

So, could it be a VIA problem? Or the VIC chip is the bad guy? Or both?
The funny musical mystery continues...
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R'zo
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Re: Sound issues

Post by R'zo »

Sounds like a via to me. If pokeing the vic produces no flaws but you are experiencing other load issues then the music is probably not loading right.
If your board is socketed then you can simply switch out the vias. If you experience a whole new but different set of problems then you knowill the culprit is your via.
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orion70
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Re: Sound issues

Post by orion70 »

I have some spare chips in the drawer, so I was able to change the VIAs. It worked for loading issues, i.e., no more strange looking games. It also loads programs with full RAM expansion (YOHO and HOWAY adventures, Athanor, Doom, etc). So thank you for the tips guys, especially to R'zo :).

The sound issues persist. To give you a measure of how wrong the tunes are, please download a couple of them recorded (bad quality, sorry) directly from the Mega-Cart music menu. The "Autumn" song and the Tetris soundtrack play definitely weird :shock: . So maybe the problem was both in VIAs and in the VIC chip? If so, has anyone ever encountered such issues involving only the sound output? Note that the pokes give apparently OK tunes!
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R'zo
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Re: Sound issues

Post by R'zo »

Your welcome. I had similar issues when I first got my vic.

Sounds like a broken pipe organ. I like it, doesn't sound right but I like it. Do you mind if I sample these sounds?

Odd that the vic chip responds fine manually but but messes up the sound on loaded programs. I would still look away from the vic chip but with nothing else at all being effected i'm not to sure. Bad timing, bad proccessor, bad inputs, expansion areas, Irq controls... should all be causing other issues.

Have you only tried loading from MC or have you also tried disk/sdiec and tape drive as well? This might help narrow down the issue.
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Re: Sound issues

Post by orion70 »

R'zo wrote:Sounds like a broken pipe organ. I like it, doesn't sound right but I like it. Do you mind if I sample these sounds?
De gustibus... :)
R'zo wrote:Have you only tried loading from MC or have you also tried disk/sdiec and tape drive as well? This might help narrow down the issue.
Yep, it loads everything fine also from the SD2IEC device.
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Re: Sound issues

Post by R'zo »

orion70 wrote:
R'zo wrote:Sounds like a broken pipe organ. I like it, doesn't sound right but I like it. Do you mind if I sample these sounds?
De gustibus... :)
R'zo wrote:Have you only tried loading from MC or have you also tried disk/sdiec and tape drive as well? This might help narrow down the issue.
Yep, it loads everything fine also from the SD2IEC device.
Does the music load and play fine from sdiec?
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orion70
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Re: Sound issues

Post by orion70 »

Nope, it does load and run games correctly (they play OK), but with weird tunes.
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