Outrun Sound issues

Larrabee

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Just picked up my old Outrun cab from the person who bought it from me a few years ago and I think something happened in transit.

I only get half of the audio effects. For example I get half the tones of the music, not the full audio I should be hearing.

Also there is no sound when I insert a credit.

I checked all the cables and everything seems good.

Any idea?
 
Hey. FWIW, the original ROMs do NOT play music during the "radio station select" screen. Only the wave sounds. If you have the hacked roms (www.finck.net/outrun), you will get music on that screen.

However, your board seems to have the PCM sound, but not the YM2151 sound. You should be able to duplicate/verify this by trying it in MAME, and going to the "slider" controls, and turning down both the TM2151 channels (leaving only the PCM channels). If that matches your sounds, then that's what's going on.

On your game, you should also go into test mode. Do the memory test first. Then do the "sound test." Try all 18 sounds, and see which ones work and which don't.

As far as what could cause the problem... it's a long list. What tools/equipment to you have to isolate and diagnose the problem? (logic probe? oscilloscope? audio probe?).
 
Did the sound test.

outrun_doing_great.png


1-4 Do not work

13 Does not work,

And all the music is missing a bunch of notes.

Did the rom test.

They checked out "OK"
 
Yup, all of that is consistent with the YM2151 sound path being the problem.

FYI, #13 doesn't do anything on anyone's OutRun. The music is made by both the YM2151 and the PCM together, which is why you hear some of the music, not not all of it.

So, the things in this sound path are: the TM2151 (IC107), of course; a YM3012 DAC, a TL-084, a 4066 bilateral switch (IC126), and an LM324 op-amp (IC 139). I ignored a couple of caps in the path, because you seem to be missing both channels and it seems unlikely both caps would go bad at the same time. After that LM324, this audio path is mixed with the PCM audio, so that's all good. It's also possible that the issue is upsteam of the YM2151, which is why you might start by checking its output. Which brings us back to the question from the my last post: What tools/equipment to you have to isolate and diagnose the problem? (logic probe? oscilloscope? audio probe?).
 
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Thanks for the info.

All I have is a multimeter. And I don't know if it is a power issue as I had the issue with the board in one cab, then moved it into the cab that had my Turbo Outrun board working perfectly. But the problem still persists.

Yup, all of that is consistent with it being the YM2151 sound path being the problem.

FYI, #13 doesn't do anything on anyone's OutRun. The music is made by both the YM2151 and the PCM together, which is why you hear some of the music, not not all of it.

So, the things in this sound path are: the TM2151 (IC107), of course; a YM3012 DAC, a TL-084, a 4066 bilateral switch (IC126), and an LM324 op-amp (IC 139). I ignored a couple of caps in the path, because you seem to be missing both channels and it seems unlikely both caps would go bad at the same time. After that LM324, this audio path is mixed with the PCM audio, so that's all good. It's also possible that the issue is upsteam of the TM2151, which is why you might start by checking its output. Which brings us back to the question from the my last post: What tools/equipment to you have to isolate and diagnose the problem? (logic probe? oscilloscope? audio probe?).
 
Let me ask a dumb question. I have a fully functional Turbo Outrun board. Do you think moving all the roms from the Outrun board to the Turbo outrun would fix the sound issue?
 
I have a fully functional Turbo Outrun board. Do you think moving all the roms from the Outrun board to the Turbo outrun would fix the sound issue?

If the other PCB-set is fully functional, then yes, I'd think so.

However, the OutRun->Turbo OutRun conversion was a little more complex than just a ROM swap. Check out p3 of this: http://arcarc.xmission.com/PDF_Arcade_Manuals_and_Schematics/Outrun Turbo Supplement.pdf

You'll need to swap TOR's custom 68000 out with the regular 68000 from the OR board, and re-jumper it due to the different EPROM sizes of the OR EPROMs. The table with the jumper changes is in the lower left corner of p3.
 
If the other PCB-set is fully functional, then yes, I'd think so.

However, the OutRun->Turbo OutRun conversion was a little more complex than just a ROM swap. Check out p3 of this: http://arcarc.xmission.com/PDF_Arcade_Manuals_and_Schematics/Outrun Turbo Supplement.pdf

You'll need to swap TOR's custom 68000 out with the regular 68000 from the OR board, and re-jumper it due to the different EPROM sizes of the OR EPROMs. The table with the jumper changes is in the lower left corner of p3.

Thanks for all your help Darren. That is correct. It is a Rev B Outrun board with the Turbo rom upgrade.

So everything I need to swap is just on the top board right?

And I am not sure what you mean about the jumpers changes, I just swapped the board with the Outrun in the same cab without issues.

So can I just put the two boards side by side and swap all the eproms and the 68000.

And how do I re jumper it? Thanks so much, if I can get this board to actually work my next step is buying the score save roms from you.
 
So everything I need to swap is just on the top board right?

And I am not sure what you mean about the jumpers changes, I just swapped the board with the Outrun in the same cab without issues.

So can I just put the two boards side by side and swap all the eproms and the 68000.

No, there are EPROMs (and lots of them) that need to be changed out on BOTH boards. Did you read the conversion document I linked last time? It has diagrams and lists of the EPROMs' locations.

Swapping a whole PCB into a cabinet, and changing out the EPROMs on a board are different. The jumpers only need attention when changing out the EPROMs, because they tell the board which type/size of EPROMs are installed on it.

And how do I re jumper it?

The diagrams in that document show where the jumpers are located. Unfortunately, it only details the proper jumper settings for converting TO Turbo, not back to regular OutRun. The best I can offer you is these high-res photos of an OR PCB:
http://arcade.ym2149.com/pcb/sega/outrun_cpu_pcb_partside.jpg
http://arcade.ym2149.com/pcb/sega/outrun_video_pcb_partside.jpg

A "jumper" is just a 0-ohm resistor, which looks like a regular resistor, but with a single black stripe. The presence or absence of these jumpers tells the board which size EPROMs are installed. Unfortunately, OutRun was shipped with a few different sizes of EPROMs, so those photos may not have the same size and number of EPROMs as yours. Perhaps by looking closely at your board, you can tell which jumpers were changed when it was converted.

if I can get this board to actually work my next step is buying the score save roms from you.

I appreciate the sentiment, but I'm afraid I don't sell them. However, the patch files can be downloaded for free.
 
Got it, just needed some clarification.

And you don't think just swapping in some other sound roms would fix the issue? I could just get another board and use it's sound roms.
 
And you don't think just swapping in some other sound roms would fix the issue? I could just get another board and use it's sound roms.

I can't be 100% certain it won't fix it, but I really really don't think so... 99% certain.

Most of the sound EPROMs are PCM data, and your PCM sound is working. There's only one ROM that holds the CPU code... and if it were bad, I'd expect the whole sound side to be jacked, not just missing the YM-generated sounds.
 
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