REPAIR GUIDE - TurboDuo: Sound Fix

peasoup · 06/03/2012, 04:48 AM

I just want to say hello and thanks to Red Ghost/toofastforyahuh and everyone in this thread what a life saver. I now have fully working cd audio and no more popping!

Unfortunately though two of the caps near the headphone opamp leaked all over the board and made a hell of a mess. Messing up a trace/pad and destroying the volume knob (all rusty and gunky now) so off to find a new one of those and then on to rgb mod !

Cheers guys.

gilao · 06/10/2012, 02:48 AM

I have a Turbo Duo and was without sound, the sound was very low even changed all the capacitors, now the Hu Card games have sound normal, but the games on CD still has very low sound, have to increase the TV volume at most and is still down, anyone know what can be ? Thank´s.

thesteve · 06/10/2012, 03:10 AM

yep, you have corrosion damage

Bekic · 03/16/2013, 06:50 AM

The soundtrack for me doesn't sound scratchy or anything, but it does hower fade out in a certain level on riot zone. It came back after i died. Does this still fit the problem-description?

Also the little cutscene when you finish a level and the guy stabs a knife in the "Wanted"-picture just cuts off at some levels and it goes straight to the gameplay. What should i do?

Thank you!

thesteve · 03/19/2013, 09:32 PM

that sounds more like a laser/adjustment issue

Bekic · 03/23/2013, 03:38 PM

Quote from: thesteve on 03/19/2013, 09:32 PMthat sounds more like a laser/adjustment issue

Is it easily fixed?

thesteve · 03/23/2013, 04:03 PM

yes, but may need a new laser.
often it just needs the pots adjusted

Bekic · 03/24/2013, 05:43 AM

Quote from: thesteve on 03/23/2013, 04:03 PMyes, but may need a new laser.
often it just needs the pots adjusted

Where can i find someone to fix it for me (and how long can i expect it to hold after that)?

thesteve · 03/24/2013, 03:44 PM

https://www.pcengine-fx.com/forums/index.php?topic=8926.0 the guide

if you need it done for you myself, bluebmw, keithcourage and a few others can handle that for you

Bekic · 03/25/2013, 12:31 PM

Quote from: thesteve on 03/24/2013, 03:44 PMhttps://www.pcengine-fx.com/forums/index.php?topic=8926.0 the guide

if you need it done for you myself, bluebmw, keithcourage and a few others can handle that for you

It's better for someone else to do it, i'd most likely just fuck it up. How long would it take if you did it? How long could i expect it to last before it starts to malfunction again?

thesteve · 03/25/2013, 10:37 PM

if the old caps are still there, it wont last long, as the caps drift and leak.
new caps in, and it should stay tuned for years

Bekic · 03/26/2013, 11:16 AM

Quote from: thesteve on 03/25/2013, 10:37 PMif the old caps are still there, it wont last long, as the caps drift and leak.
new caps in, and it should stay tuned for years

That's pretty durable, by that time it won't even get me frustrated. How much time would you need to put new ones in?

Also, i wonder if it's possible that aside from the sound and some cutscenes citting out that the actual graphics and music themselves have deteriorated in terms of quality (or is it just works or doesn't)?

thesteve · 03/26/2013, 11:48 AM

the sound mixing does deteriorate, but the grafx not
currently no backlog (couple weeks here max)

Bekic · 03/26/2013, 12:00 PM

Quote from: thesteve on 03/26/2013, 11:48 AMthe sound mixing does deteriorate, but the grafx not
currently no backlog (couple weeks here max)

I see. How do i know how much the sound has deteriorated at a certain point?

thesteve · 03/26/2013, 01:30 PM

the music will fade, making the other sounds too loud
hard to tell without a test on another system

Bekic · 03/27/2013, 02:08 PM

Quote from: thesteve on 03/26/2013, 01:30 PMthe music will fade, making the other sounds too loud
hard to tell without a test on another system

But that would be restored to along with the other problems i had? How long will it take before deteriorating after the fix?

thesteve · 03/27/2013, 05:23 PM

new caps should outlast the originals 20+years

Bekic · 03/28/2013, 02:18 PM

Quote from: thesteve on 03/27/2013, 05:23 PMnew caps should outlast the originals 20+years

So it does restore the sound quality too?

thesteve · 03/28/2013, 07:20 PM

yes

Jay See Double You · 04/17/2013, 09:38 AM

Hey guys! First post! I have a US Turbo Duo that I got in 2003. I fired it up a few nights ago for the first time in a few months, and let me try to explain what I noticed: There was static scratchiness in the sound, but the sound proper was not distorted. Does that make sense? I would occasionally notice the static on top of otherwise clean sounding music and sounds, but mostly, I'd notice it when there was no music, such as when I was playing Hit the Ice. I did not notice any issues with video, or performance in other capacities. I don't recall ever noticing this static before.

The only environmental change was that there was a mouse back behind the systems that I caught and killed in a trap. But the only way I can imagine that making any difference was if he chewed on either the AC or AV, and I don't think he did. When the trap caught the mouse, there was a wire under the mouse that I had to pull on to separate from the mouse/trap, that could've been the TD AC cord, but I'm not sure - I didn't check. There is also a new AV selector box that I am using, but I'm not noticing any similar effects on the other systems hooked up to it (Genesis/SNES/NES).

Do you think I'm dealing with this capacitor issue, do you think I'm dealing with bad AV and/or AC cords, -or- do you think I've got something else (probably more serious) going on? Let me know! If you need me to, I can probably capture some audio for you!

Would appreciate your expertise on this! :-)

Thanks!

p.s. Unrelated question (I hope it's okay that I'm killing two birds with one stone here): If I understand things correctly, there is no region lock on CDRom2, Super CDRom2, and Arcade CDRom2. I'm also under the impression that all Turbo Duos can run all three CD-Rom formats without requiring the accompanying Hu Cards. Am I correct? It seems to me that, if so, and this Turbo Duo I have is easily fixed, then the best course of action for me is to keep it, use it for all region's CD-Rom games, and American Hu Cards, and rather than buying a pricy region card adaptor, just get a PC Engine or (if I'm really ambitious), Supergrafx off e-bay in order to play the Japanese Hus. Am I right? If I'm wrong, what do you suggest? If I am right, but my Duo's gonna be an expensive fix, I might be better off buying a Japanese DUO R/RX, buying a standard American TG16 with turbo-booster, and going that route (since the American Duos are soooooo much more expensive!) Do you agree?

Thanks guys! Look forward to interacting with you guys in the future!

Cheers!

-JCW

NecroPhile · 04/17/2013, 09:53 AM

Sounds like caps to me, but whatever is wrong I'm sure one of the guys here can get it fixed up for a reasonable price. If it's not caps but they haven't been changed yet, get 'em done before they leak and corrode the PCB or take out some other component.

As for CD formats, discs are region free but system cards are not. Your TurboDuo can play CDs and SuperCDs with its internal system card, but you'll need an Arcade Card Duo* (and region mod of some sort to use it) to play Arcade Card games. For region mods, don't waste time with overpriced and often finicky converters; get a switch installed or buy a re-capped PCE Duo or a Duo-R.

* - an Arcade Card Pro will also work, but they're pricier

Jay See Double You · 04/17/2013, 10:36 AM

Thanks NecroPhile! I have thought about looking into toggle switch region mods for this! If I were to mod the system to handle JP Hus, would there also be any way to mod the system so that it's internal "system card" is equivalent to the Arcade card instead of the Super CD-Rom2 card? Also, I think I know the answer to this already, but I suppose there isn't any way to mod the thing to add Supergrafx support as well, right? So we don't veer this thread off topic, you can PM me if you'd rather. :-)

NecroPhile · 04/17/2013, 10:55 AM

The short answer is there's no way to add AC and/or SG support to a Duo. I suppose it's technically possible to add AC and SG support to a Duo (look at the crazy shit people like Ben Heck cobble together), but it'd be a ton of work, costly, wouldn't fit in the original case, and would require cannibalizing parts from a real AC and SG anyway.

BlueBMW · 04/17/2013, 11:48 AM

I could see possibly hijacking the lines to the internal system bios and running it to an arcade card, but yeah it would require an arcade card still... itd be simpler to just use the arcade card in the system.

Byron

Jay See Double You · 04/17/2013, 09:44 PM

Thanks, Byron!

Simpler, yes. But I like the idea of not having to mess with popping a card in and out (not to mention risking losing or breaking it). I don't know whether I'll pursue that or not. But it's neat to know that something like that could theoretically be done. I will plan on having the caps replaced, and probably also looking into a toggle mod to switch between US / JP HuCard pin config. I'm sure a thread exists for that here. Does anyone have a link?

I guess I'll noodle the Arcade 3 card internal mod idea. It looks like the Arcade 3 Duo card is not too pricey, and even the Arcade Pro cards are only about $80-$120 on "the bay", which is not too bad, especially if they're your key to the best Neo Geo ports of the 16-bit era this side of the Neo Geo itself (which I do have - JP AES, and JP Model 1 NGCD), then I think they're probably justifiably priced. (What is the diff between the AC DUO card and the AC Pro card, btw, and are there any games that absolutely require the AC pro to run?)

Thanks for letting me pick you guys' brains on this stuff!

Cheers!

BlueBMW · 04/17/2013, 11:51 PM

Since you have a Duo system you just need an Arcade Card Duo. The Pro cards are for systems that don't already have system 3.0 built in.

Look over this compatibility guide for some more information on this subject:

https://www.pcengine-fx.com/main/nec_compatibility_guide.html

Region mod info can be found in this thread:

https://www.pcengine-fx.com/forums/index.php?topic=10112.0

Also, you should be able to find an Arcade Card Pro for less than $80.. that seems like the top of end of what it should cost. An Arcade Card Duo can probably be had for closer to $30-$40.

Mystery · 05/09/2013, 06:52 AM

Hey guys, it's been a while since I last posted here, but I got really frustrated with my Duo repair that I put it aside for over a year and dug it back out today.

Anyways, here's the status:
I replaced all caps, all 4558 amps and even the M51131.

The issue is the following: I get no audio out of the system but I get very very faint sound on the headphones if I crank it up to the max.

Unfortunately I'm no expert, but I read this topic (https://www.pcengine-fx.com/forums/index.php?topic=7328.30) and tried measuring some voltages to see if there's anything suspicious.

So, the 4558 at C506 has a very low output on pins 1 and 7. (Duo_R only had one faulty channel and his amp at 506 had only low voltage at 7).
I also checked the surrounding caps and both the C610 and C604 ones give me lower than expected voltage (again, it's consistent with Duo_R's error, as only the cap at C604 had low voltage for him).

All the other 4558 amps seem to have a correct output and so do the other surrounding caps.

But this is where I'm stuck and I don't know where to investigate further. There might be a bad connection somewhere or damage due to corrosion from the old caps...I'm not sure how to proceed from here. Any suggestions?

thesteve · 06/05/2013, 09:46 PM

could be a bad amp, or a bad connection
check the reference voltages (inputs) on the affected amp, odds are either the - inputs are high or the + inputs are low

michichan · 06/29/2013, 02:59 AM

Hi, and thanks already for all the wonderful maps, schematics, and videos I've seen from everyone!

I'm attempting to replace several caps (I don't have the time or money for a full replacement right now, so I'm just hitting the bad ones) and I've gotten them all off the board without any damage EXCEPT for C323. For some reason (probably corrosion) the trace just came right off the board, and I'm guessing I'm gonna have to use a wire now. However, I'm having trouble figuring out the path, since it seems to have two? I read somewhere that C323 has a second source? If someone could help me figure out where I need to solder this wire, I should be able to get everything rolling. Thanks! (If you need a picture, I can get one)

Fidde_se · 06/29/2013, 02:20 PM

Well C323, the minus side connects to the ground, which can be connected a little here and there, and the plus side goes to leg 3 of IC506 (4558).

michichan · 06/29/2013, 02:43 PM

Ah, ok! Only the plus side came off, so if I just run a trace wire to the IC's 3rd leg, I'm all good?

Fidde_se · 06/30/2013, 06:08 AM

Thats correct

Everblue · 07/05/2013, 01:10 AM

Not sure is this is related but I will have a go:

I just bought a brand new old stock white PC Engine (the very first model) along with an AV Adapter for it as sold here:

http://www.otakus-store.net/en/nec-pc-engine/155-nec-rgb-av-box-for-nec-pc-engine-console.html

It works great but audio volume is around 40% too low, no distortion or anything....

Anyone knows if this is a case of the capacitors needing replacement, or audio from a white PCE's expansion port is too low? I have confirmed with the maker of the AV adapter that it doesn't come with an audio amp.

Any help is appreciated

Thanks!

michichan · 07/05/2013, 06:43 PM

So I've been working on the capacitors, but I've got a problem where the audio has a lot of electronic static noise when you turn on the system, and then sometimes CD audio will play for a moment and then the whole system audio just kinda dies. Nothing seems to be crossed or short circuited, and I've redone several solders, but it just keeps happening. Any clue? And if there's not a clue, I'll probably just have to send it off...but I don't wanna admit defeat yet!

BlueBMW · 07/05/2013, 08:10 PM

How much cleaning did you do once the caps were removed? Often the fluid gets on everything and will cause static / shorts. Be sure to check around the amp chips on the backside of the board too. Look for any vias or traces that have turned black.

blueraven · 07/05/2013, 11:26 PM

Make sure that the trace wire you installed has a solid connection. I had the exact same problem with my primary unit a year or so ago, and it turned out to be a bad connection from the wire to the IC, and it "popped" off like you described. Also, like BMW said, use a toothbrush and cleaner to get the grime off of the trouble areas, and remove any unnecessary flux. You did use flux on the wire?

michichan · 07/06/2013, 12:34 AM

I did use flux, and I did do quite a lot of cleaning, but not on the underside. I'll try that and also try redoing the line to the IC. Hopefully one of those will work...

thesteve · 07/07/2013, 10:10 PM

if all sound is fading in or out, it could be a missing voltage to the amp by the AV plug
had one here that had no sound for the first few min, then would crackle to life.
found an open via feeding a ref voltage to that amp.
the amp would generate the voltage after some time, masking the issue

kisaku · 08/30/2013, 12:53 PM

hello, i have a sound problem with duo. when i start it, it is all ok, but after about 5 MINUTES the audio fades in and out... i replaces the post op amp, but nothing changed... should i change other caps? or is it a laser problem?

thesteve · 10/10/2013, 03:54 PM

Laser issues will cause only cd sound to drop, if chip sounds fade its not cd related 2

bishopcruz · 02/06/2014, 11:29 AM

Ok, question

My Duo just came in, and CD audio is working great, but any Chip Audio/SFX is VERY low. The system was supposed to have a complete cap replacement, though I haven't looked inside to check. Is there something else that could be the problem? I checked it on both Turbochip games, like Legendary Axe and Bonk, and CD games like Gate of Thunder. In Bonk I'm only hearing like half of the music. In Axe, music SEEMS fine, but the sound effects are nearly non-existent. It's prettty weird overall.

I did have it region modded before it was sent out to me, but I assume that shouldn't be an issue.

ClodBusted · 02/06/2014, 11:33 AM

I had the same issue, mostly with digitized speech sounds. A FULL recap solved the problems. Some of the caps had seized really bad. Often you wouldn't see damage to the PCB underneath them until you removed the old caps.

bishopcruz · 02/06/2014, 11:52 AM

Problem is it was supposed to have been recapped already.

I found a youtube video with my exact same problem:

PC Engine Longplay [006] The Legendary Axe

Just kinda sucks as I was really looking forward to this without having to worry about repairs on the caps.

Also if the PCB is damaged can it be fixed?

NecroPhile · 02/06/2014, 11:56 AM

It's possible that something else could be the problem, but 99% of the time it's caps or cap related. Even if it's been recapped, it usually ends up being a bad connection on a cap(s), unrepaired corrosion caused by leaking caps, or cap juice left on the board that's shorting something.

bishopcruz · 02/06/2014, 01:32 PM

Quote from: guest on 02/06/2014, 11:56 AMIt's possible that something else could be the problem, but 99% of the time it's caps or cap related. Even if it's been recapped, it usually ends up being a bad connection on a cap(s), unrepaired corrosion caused by leaking caps, or cap juice left on the board that's shorting something.

OK.

Thankfully after I unplugged it, to see if my star screwdriver would work, (it didn't) I decided to plug her back in and check the headphone out to see if it was better. So I plugged everything back in, and well, while the audio from the DIN still seems a little worse than out of the headphone jack, the problem I had before is gone for now. I'm no longer missing half of the sound effects like that video, and out of the headphones, it definitely seems better. I may just run the stereo out of that jack to the TV if need be. I have no idea why the sound would be working fine now, but not an hour or two ago. Really weird.

Other than that the thing is working great. Burns are working well, as is my copy of Ys 1 and 2, though I'm getting a bit of skipping (might need to have it resurfaced) now to test out CF2, Exile Ys 3 and Vasteel.

javilevel · 03/22/2014, 07:33 PM

Hello

First sorry for my english, I'm from Spain.

I have a TurboDuo, and I have the issue problem, the sfx sound works good, but de music CD don't work.

I don't have the time and the experience for repair my DUO, is there anyone in the forum who can do it for me for money?

Thanks.

michichan · 04/17/2014, 11:11 PM

So, I tried fixing my PCE Duo last year and eventually gave up, but after recent interest in it, I've tried again. A number of capacitors were replaced, but C616 lost one of its pads, and so I just couldn't get the sound to work. I replaced a few more and managed to get a solder that hits the edge of the lead for C616, but it's still scratchy sometimes and I'm afraid it's way to fragile. I want to run a lead wire to the contact point, but I can't figure out where it goes. There looks to be three different traces on this contact. Anybody know what I should be connecting to?

grunthos · 04/20/2014, 07:22 AM

I MUST SAY THANK YOU TO D-LITE & EVERYONE ELSE FOR THEIR EFFORTS
HERE. I RE-CAPPED MY TIRED TURBODUO AS NO-ONE ELSE IN THE UK
WOULD DO IT FOR ME ... IT NOT HAS 100% SOUND AGAIN. SO HAPPY!
I replaced all 6 caps in this photo. It wasn't easy for someone with my low
skill level, but if I can do it, anyone can. THANK YOU AGAIN.

/r9x600copyxo4.jpg

THANK YOU ALL, THANK YOU ALL, THANK YOU ALL, THANK YOU ALL, THANK YOU ALL

Keith Courage · 04/21/2014, 02:04 PM

Quote from: michichan on 04/17/2014, 11:11 PMSo, I tried fixing my PCE Duo last year and eventually gave up, but after recent interest in it, I've tried again. A number of capacitors were replaced, but C616 lost one of its pads, and so I just couldn't get the sound to work. I replaced a few more and managed to get a solder that hits the edge of the lead for C616, but it's still scratchy sometimes and I'm afraid it's way to fragile. I want to run a lead wire to the contact point, but I can't figure out where it goes. There looks to be three different traces on this contact. Anybody know what I should be connecting to?

Follow the traces from the pads. There should be a small via hole near them. You can push a wire or extra capacitor end through it and solder it where it needs to go.

Zer0-2k11 · 07/04/2014, 04:09 PM

Hi everybody,

I'm in need of help. Sorry about the long post.

I got a PC engine duo on ebay that was described as "Working but no audio" about a month ago. When i received the Duo, first thing i did without testing it was i replaced all the caps with a cap kit i got from console5. After replacing all the caps, the audio was working. Then i proceeded to RGB mod it using the THS7314 method (8 Pin Din, Etc). Before doing the RGB mod it had CD drive issues so i ordered a new laser. After doing the RGB mod i decided to test my Street Fighter II HuCard i just received that day to see if everything was working alright and i noticed i had no sound again. So i looked around the audio circuit i noticed i had 3 caps backwards, C604, C614 and C678 (Audio circuit too) and i corrected them but still no sound. I also redid the 8 Din installation but again nothing

. I also tried to clean around the audio circuit with some 99% IPA just in case if there was any cap residue that was shorting things outbut that didn't work out either. A day later after receiving a new HOP-M3, I manged to fix the CD drive back up again with a new laser and with a few pot adjustments (See my post in laser adjustment guide thread) and the CD drive is back up and running. So now i have 2 problems

, one is the no audio problem and the other one is a ceramic capacitor at c518 has been damaged somehow. I don't know if it was like that before or if i did it. Would anybody have any ideas on how to fix the audio and 2, does anybody know the capacitor size and value?. I'm starting to think i damaged the 4558 because of the capacitors being backwards. If this is the case, would a RC4558 work as a replacement? (Texas Instruments 4558). Thank you everybody in advance for your time .