PCE Super CD-ROM2 Sound Problems

[farankoshan]

hey guys!

I'm a little bit of a noob here as a member, but have been benefiting for many years lurking around from many of your helpful tips & problem solvers. 

Anyway, I had a problem I was experiencing with my Super CD-Rom2 and thought to ask Sunteam Paul about it. He told me to post about it here since he wasn't entirely sure where the problem lay.

Here is a transcription of that message:

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Dear Paul,

I was wondering if you could help clarify something for me.

A few months ago, I lucked into a good deal for a Super CD-Rom2 in Hong Kong, & it now connects conveniently to the back of my existing Core Grafx II. The overall aesthetic works for me since both systems are the same shade of gray with orange colored labeling, plus the lens works just fine. There is one weird thing about it. I would hook up the 5-pin DIN AV cable to the Super CD-Rom2 unit, I noticed that whenever I just hook it up and boot up a CD game (Final Zone II), the sound that comes out is scratchy, mildly crackled & of really bad quality. However after about 20 or so minutes of keeping the system on, the sound improves to being perfectly fine. Why is this?

Also, after playing with it since then, I recently tried playing Super Darius on it and got the same "scratchy" result. However, there was one time when I accidentally left the AV cable connected to my CoreGrafx II instead. The result was a much louder & automatically clearer sound, without need for "warming up". Is this normal? I thought all the video/audio signal, once the cd-rom was connected, is fed from the Super CD-Rom2. Can the signal really be fed back to, and out from the CoreGrafx II? It seems to sound like CD quality music (of the Redbook audio quality, having verified the cd being played off a cd player afterwards), so am I really to believe that signal can be fed from both ports?

I'd really appreciate your help here. Thanks, Paul!

Franco Chan
Manila, Philippines

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I read on a few threads about a certain "warm-up" time that Super CD-Rom2's need as they get older, and how leaving the Super CD-Rom2 running a game for about 15-20 minutes can clear up the sound well. But when I tried turning on the unit (with a CD inside), with the AV cable stuck through the CoreGrafx II AV out, I got some clear audio. I just wasn't sure if this was possible at all... Or is this sound somehow inferior to the CD quality audio I could be getting from the AV out of the Super CD-Rom2.

Hope you guys can help clarify this.

Thanks for your help!

[RR1980]

usually "scratchy" sound means the sound caps in the SCD unit are leaking which is a common thing they are known to do and some members here have found like you that having the av come out of the Core Grafx/CGII instead of the SCD can solve this problem. It might still be a good idea to replace those caps none the less tho.

[farankoshan]

usually "scratchy" sound means the sound caps in the SCD unit are leaking which is a common thing they are known to do and some members here have found like you that having the av come out of the Core Grafx/CGII instead of the SCD can solve this problem. It might still be a good idea to replace those caps none the less tho.

Will leaky caps lead to breaking the system completely?

First of all, I'm not qualified to open up this unit. Secondly, even if I find a local tech-guy around here (a guy who fixes cellphones, stereos, and TVs), would cap replacements be easy to find? Are they standard cap-types?

[RR1980]

Next time you come on here ask around at the shout box there are a few guys there who have done cap replacements for SCD/Duo and offer the service for a nominal fee.

[farankoshan]

But would this require sending the item out of the Philippines, or buying the parts online and bringing them over here to have them replaced by someone capable?

Thanks for your help so far!

But if I intend to just feed signal from my CoreGrafx II instead, should that be fine for a long time?

[RR1980]

yeah if you need one of the forum members to replace the caps for you you'll need to send the unit out of the philipines but if you know someone who has some repair skills there are also step by step guides on how to replace the caps here so maybe you can just buy the caps and have your friend replace them for you.

[csgx1]

But if I intend to just feed signal from my CoreGrafx II instead, should that be fine for a long time?

It's recommended that a full cap replacement is done since there's a possibility that other caps might start to leak soon after and can cause other problems/damage. 

The Coregrafx II output can be used but unfortunately the audio is not stereo. 

Some helpful threads on this subject...
https://www.pcengine-fx.com/forums/index.php?topic=9544.0

https://www.pcengine-fx.com/forums/index.php?topic=10022.0

[farankoshan]

STEREO... That answers that question for me. Thanks, guys! Big, big help!

*For the benefit of a search engine lurk:
So, when playing CDs from a Super CD-Rom2, feeding audio from the AV Out of a CoreGrafxII instead will not give STEREO sound. Stereo only comes from the AV Out of the Super CD-Rom2.

[nat]

Stereo sound aside, not getting your caps replaced means your Super CD-ROM unit will ultimately fail. Yeah, I know all electronic devices will fail one day but it will fail relatively soon comparatively speaking. Failing/scratchy sound is merely the first noticeable symptom of the leaky cap issue. Eventually all the caps will leak, as has been mentioned, and the unit will no longer function correctly. Worse still, the gunk that leaks out is conductive and has the potential to short out the internal components, causing permanent damage.

Just get the caps replaced. If you have to send it out of the Philippines, so be it.

[Keith Courage]

Are you sure stereo doesn't come out of a core grafx II output? I am pretty sure that I can tell the difference in sound from right to left audio channels when playing a chip game. Maybe the CD drive only comes through as mono? I'd test an audio CD on it that usually has different sounds from each channel just to know for sure.

[farankoshan]

Ok, I had all the caps replaced and hooked it up to test it and... the sound was still cracky.

Each and every cap indicated on BlueBMW's very helpful cap guide was replaced with brand new ones and to no avail. The sound coming out of my Super CD-Rom2's AV Out is still cracky with low levels coming out bad as before. From the CoreGrafx II's AV Out, the sound may not be in audio-divided stereo, but it's much clearer and perfect - for the MONO signal, of course, that you guys say it gives.


Any ideas, guys?

[farankoshan]

There is a bit of an improvement that I want to add.

As I posted earlier, the "warm-up time" that normally the audio would need was about 20 mins, now the unit took 5 on my first try until the cracky audio cleared up.

Could it be possible that the new caps needed to warm-up and get acquainted to their new home before fully affecting the whole unit? Almost like a guy, de-toxing from a night of bad alcohol, needs a day of water and cleaner fluids before fully becoming alcohol-free again for his drug test? (hahaha! Excuse the random example. :p)

I'm serious about this though. Could this be the case? Over time, and after more uses, could my super cd-rom2 eventually begin booting up "cold" with NO audio problems?

[BlueBMW]

If you had leaking caps, its very possible that there may be some corroded traces and bias (holes through the PCB) caused by the leaked capacitor fluid.  When caps are changed out, you need to make sure that the board is good and clean and that no old cap fluid remains.

Some break in on caps is expected but generally speaking you should get full performance on the first power on with new caps.

Let us know how it does!

[farankoshan]

I will be doing some cleaning in the next few days.

Another problem arose though. Out of my 4 SCD games, only 2 games boot up now. The lens is the original lens and I do have some replacement lenses, but if 2 of the CDs boots up fine, could it be the discs? I don't know if they're scratched up exactly, but I used to be able to play them fine before the procedure.

[farankoshan]

Just wanted to update on my "crackly sound" that didn't go away after the full cap replacement (see page 1):
Once I replaced the lens on my unit, the sound problem disappeared completely. Now, whether it was the new lens that fixed it, or the extra cleaning of the board after the new lens was installed, the sound comes out clear. ;)

So to whoever may be struggling to fix a sound problem, keep the above info in mind.

[nat]

Replacing caps on a board without cleaning the board is almost completely and utterly pointless.

I recommend a full dishwasher cycle to remove all traces of conductive electrolytic after a cap replacement.

[farankoshan]

Replacing caps on a board without cleaning the board is almost completely and utterly pointless.

I recommend a full dishwasher cycle to remove all traces of conductive electrolytic after a cap replacement.

I agree with the above, provided you know what you're doing.
I suppose that with these sorts of things, CD lenses & capacitors both play roles in running a system (among many other components) and replacing/fixing these one by one can help. Thanks to forums like these, expected time devoted to trial-&-error can be minimized. ;)