Igt S2000 sound problem - humming and static

[Bettor Slots]

I think I have the problem solved.  I had Mike send me a PM of the exact model of resistor that he purchased at Radio Shack.

He ordered stock number 271-1130 which is a 47K Ohm 1/2W 5% Carbon Film Resistor - (so does this mean 47,000 Ohms ???)

The stock number that I ordered and had success with is the 271-1105 which is a 47 ohm 1/2W 5% Carbon Film Resistor - (no "K" in the description).

Would this be the reason??  Seems like.

[dpalmi]

Hello all!

When I have done this in the past I have used a lot smaller resistor than 47K - depending on the machine and if it has a Multimedia board - somewhere between 47 ohm and 200 ohm.  When I tried it the 1st time I bought a 10k potentiometer like posted here and it worked - but it was SO touchy trying to adjust it - that was because the 10K was way much more than needed.  I went and bought a much lower resistance one and then I had much better control.  I've always been surprised by the posts here about how large a resistor people are using....

Dan #2

[Karaoke Mike]

Hi, back, I went by what was o nthe first page, so I should use a 47 and not a 47k? Also I bought a 10k .5watts pot , part number 271-1715
could i ue these? Thanks for all the input

[stayouttadabunker]

I sent Mike a resistor color calculator chart....might help determine what he has exactly...
going by the colors on his resistors and entering those in the calculator will tell him what he has really...
this is a cool resistor link>>>


http://www.dannyg.com/examples/res2/resistor.htm

[dpalmi]

Hello all!

Here is a great web page to calculate resistor values or use the pic below

http://www.engplanet.com/content/resistorinfo.html

Dan #2

[Karaoke Mike]

All right, I found a 220 resistor and actually had the sound coming through. Tomorrow I will be getting some 47 resistors. Hopefully tomorrow it is happy times. Thank you all and K+ for all the help. Mike

[cfh]

or my resistor page:
http://marvin3m.com/resist

[brichter]

Just remember: Bad boys rape our young girls but Violet gives willingly.

And, if you're Ozzy, this one works for the tolerance codes: Bad beer rots our young guts but vodka goes well – get some now

[U.S.AutoService]

        Ok , I had the noise (buzz, humm) what ever you want to call it.. I put in the resistor, but didn't like the out come. But what I did was swap the sound simm  into a good slot machine and the sound followed the simm.  So I guess this means the simm is jacked up right ?       How can I contact to get me a new one ? Its wild thing red devil... would like to have one that has Sam Kinnision version of the song instead.    
P.S. I stuck the wild thing in a Phantom of the Opera with nudge.... wow , funny stuff from the speakers...
Also looking for reel strips and all that is needed to make a new Wild thing (Black Leather) , Glass etc...

Thanks..

     U.S.Auto Service
        Dan

[Karaoke Mike]

I finally found the perfect resister for my vision speakers. I found that 10ohm allowed it to be loud and no background un-needed sounds.

[Bettor Slots]

Thanks for the info Mike....were these 1/4 or 1/2 watt resistors?  Do you have a part number from Radio Shack?

[Karaoke Mike]

They are 1/2 watt
radio shack number #271-1101
I was never totally happy with the sound on it. With 47 ohm and using the mm2 sound card it had to be on 10 volume for it to sound ok. Then went to mm2 and no resisters and it had a slight sound on volume 2, then finnally went with where I am at now and on volume 5 it is loud, clear and sounds good. Will put it on video later. Good Luck

[Karaoke Mike]

Hey Tacman, I thought you would enjoy seeing this back in the machine.



original sound

<a href="http://www.youtube.com/v/Gwu3clkLQ1I&rel=0" target="_blank">http://www.youtube.com/v/Gwu3clkLQ1I&rel=0</a>

New Sound

<a href="http://www.youtube.com/v/NOmDmmg6tbI&rel=0" target="_blank">http://www.youtube.com/v/NOmDmmg6tbI&rel=0</a>

[tacman]

Hey, always a good game to play,  but the question is how long can you resist changing it to something else? Or has that already happened? 

 Dan (tacman)

[Karaoke Mike]

I think it will be Thursday. Probably back to the Munsters.

[CaptainHappy]

They are 1/2 watt
radio shack number #271-1101
I was never totally happy with the sound on it. With 47 ohm and using the mm2 sound card it had to be on 10 volume for it to sound ok. Then went to mm2 and no resisters and it had a slight sound on volume 2, then finnally went with where I am at now and on volume 5 it is loud, clear and sounds good. Will put it on video later. Good Luck

Hey folks,

I hope that any of you are able to help me by chance....

I have tried doing a resistor mod that everyone has been doing as I had the bad hum coming out of the left speaker on my new Super Spin Sizzling Sevens 2003 S2000, with sound SIMM and audio amp board. I looked at the last post as it was the latest and chose to use the same 10ohm resistors that were used as it was the last post, and it seemed to have good results. I have not done the bottom speaker yet as I have had an issue with the top speakers. The sound used to be set around 2, and now I have it up to 7 or 8 to be able to hear it. The loud hum is barely noticeable, and the sound is decent, but the left speaker has no sound now, just a low buzzing. (I unplugged the top exhaust fan so that I could hear better now.) I thought that it could be my soldering or a bad resister, but I checked continuity, and also read the right value on the resister. So I swapped the cables from left to right, and the sound followed the cable. The sound went to the left speaker, and the buzz went to the right speaker, now I unreversed them. Anyone have any suggestions, or has seen this particular scenario before? I have not undone the mod yet depending on what people suggest. Maybe I should be using the 47ohm??? Would it be different on a Vision like Mike was modding, as opposed to an S2000 like I have.

Also a bit more information.... My initial problem was the loud humm and buzz coming from the LEFT speaker, it was not coming from any other speaker. This seems to follow exactly the problem that someone described earlier (quoted below) in which they corrected the problem by following the IGT CN referenced. IS this a different problem that some have encountered or the same problem that everyone has had? I was thinking this is not supposed to apply to me since I think my MPU is 75510504 Rev E from peaking, but I am not positive as the MMLII board is currently stuck on the MPU as one of the screws is stripped all to hell, so I did not try to get it off right now. One problem at a time! Is this a differnt problems than what people describe above or the same???

CaptainHappy

I had the same problem with my S2000 and the sound humming from the LEFT speaker only, I followed IGT CN 3633 and it solved the problem!

Disclaimer: Good soldering skills with a sharp tip is a great help, delicate soldering of the MPU is required!

Please be advised the modification only requires to MPU P/N 75510502 Rev A and 75510504 Rev A. Raw boards 75510504 Rev B and 75510530 Rev C will not require this work. These changes have been incorporated into the artwork.

- Remove R26 on the backside of the MPU
- Lift pin 4 of U43 and clip close to the chip (tricky!)
- Hook up 24ga wire between U85 pin 5 and C70 pin 1
- Hook up 24ga wire between U85 pin 4 to C57 pin 1
- Hook up 24ga wire between C70 pin 1, J1 pin 18b
- Hook up 24ga wire between J1 pin 14a, C61 pin 2, and C70 pin 2
- Hook up 24ga wire between J4 pin 22a, J4 pin 22c, and J1 pin 14b

My machine has the multimedia board and also has amplified speakers, it worked on my machine. If your machine is anything different be cautious!

[Bettor Slots]

Can you troubleshoot this first by changing out the sound amp board in the top box and give us the results?  Also try seperating the speaker wires and pushing them as far away from from any power source lines.

Switching to the 10 ohm resistor is not really the solution here, it will cancel noise just as the 47 ohm resistor does  and will also allow the sound to be even a little louder as some were finding that with the 47 ohm resistor the sound is not quite loud enough even when set at 10....those damn kids and their rock music...gonna ruin their ears I tell ya...

[CaptainHappy]

Can you troubleshoot this first by changing out the sound amp board in the top box and give us the results?  Also try seperating the speaker wires and pushing them as far away from from any power source lines.

Switching to the 10 ohm resistor is not really the solution here, it will cancel noise just as the 47 ohm resistor does  and will also allow the sound to be even a little louder as some were finding that with the 47 ohm resistor the sound is not quite loud enough even when set at 10....those damn kids and their rock music...gonna ruin their ears I tell ya...

I had tried to swap amps earlier, and it reacted funny, so I shut it down immediately. It started to make some bad sound coming from the base bottom speaker as best I remember, so I hit the power fast. I feared electronics frying? I went back to the original amp and turned the power on and there was no sound at all. I played one game and it played OK, but when the 4th reel reacted weird and very slow. I cycled the power and it was back to the modified state with the resisters on the L and R speakers and the sound was only coming from the right speaker, and the left speaker had a slight buzz. I have looked at the amps and now realize they are slightly different. The spare on I had I got a couple years ago from someone to put into my 1997 S2000 Vision style machine, but that never happened. (no LCD BTW, std 3 reel) The part numbers are different.. Spare is 76924502 RevA, and the one in my new machine is 76928000 RevA. Pics attached for comparison. SORTA CHICKEN TO TRY AGAIN!  

I am sure that I did the correct wires. Also I did the mod on the machine side, not the speaker side of the connector as there was more wire available on that side. I do not think that should matter.

Are you thinking something is wrong with the AMP? Have you seen this before?
Could the resister MOD damage the amp?

Did your machines have the noise only in the left speaker pre-mod?
After the 10K res mod does anyone still get a little buzz in the left speaker?

Should I unsolder the resisters to test the existing amp again in an unmodded state? I knew I should have tried with aligator clips first!
(If I leave the resistor inline, and clip over both ends with a jumper would that create the same UN-MODDED condition? I forget my basic electronics.. not sure if the jump would work for a quick test???)

I just did a few other quick tests before finishing this post...

After the amp swap scare, I had left the base speaker out. As a test I put it back in and it gets the same buzz that the left speaker gets! (Remember this connection is still un-modded.) Almost seems like too much bass right now... The mod would probably balance this correct?

I decided to try the sound tests to see if anything was happening at all with the left speaker. The weird thing is that the speaker gets a very low sound out of it. I can hear the same as came out of the right speaker. I did another experiment of unlugging the right speaker to hear better. I can confirm that the left speaker is getting the signal, but at a really low level even at volume 10.

Not sure if this helps??

Also as a final reminder... Amp and speakers were working prior to these mod's, just had the loud whine and humm in the left speaker.

Thanks to the people who help on this.

Regards,

CH

[StatFreak]

Is it possible that this could be caused by a bad ground/cold solder joint somewhere in the left signal portion of the amp?

[Ron (r273)]

Is it possible that this could be caused by a bad ground/cold solder joint somewhere in the left signal portion of the amp?

What happens when you turn the stereo off?

[Bettor Slots]

Is it possible that typically the bad sound coming from the left speaker is a result of the printer being there?  The speaker wire is always sandwiched between the cabinet and the metal frame of printer which is energized.  I recently shopped out a 5-reel MS LGM Vision that was getting a popping sound in the left speaker.  I found the speaker wire wrapped around the power cable that went to the printer.  After I unwrapped and seperated the cables the popping was significantly reduced and less frequent.  Then installed the 47 ohm resistor and had perfect sound.

Also, when you changed out the amp before, is it possible that you had the volume up high to compensate for an amp that was going bad?  So when you installed a new amp it pushed the sound signal at full strength resulting in the loud noise distortion from your speakers.  Now that you have the resistors installed, I would suggest changing the amp out again with the volume set to 6 before you make the swap.

[Railroad94]

On the original problem I would also check the harness that is plugged in on the left, it has the wires from the base of the machine that go to the amp.  Have seen some with 4 wires and others with 6 wires, I believe the six wires is the channels separated for true stereo sound.

[CaptainHappy]

Is it possible that this could be caused by a bad ground/cold solder joint somewhere in the left signal portion of the amp?

What happens when you turn the stereo off?

Nothing... Sound comes from right speaker. Low noise and BUZZ in left speaker. If I unplug right speaker and listen close to left speaker can hear the normal game sounds coming through under the BUZZ. (Could it be BUZZ's fault? HA HA )
I have tried a different speaker as well to rule out a bad speaker.

Another note: The noise/buzz seems to follow the reel spin, which makes sense as this IGT problem was identified to happen with backlit reels as is described in the CN. I say this because when I get a pay that causes the 4th bonus reel to decellerate, the interference will change with the speed of the slowing 4th reel!

On the original problem I would also check the harness that is plugged in on the left, it has the wires from the base of the machine that go to the amp.  Have seen some with 4 wires and others with 6 wires, I believe the six wires is the channels separated for true stereo sound.

It has the 6 wires where plugged in on the left.

CH

[Foster]

I believe it is caused by the back lit reel controller.


I even relocated back lit controller power connection from the Netplex harness for the top box (My connections where near the motherboard) to the actual power wires going to the motherboard.
I have done the MPU rework as posted in this topic for the 02 Rev A board.
I decided to try to see what may be causing the buzz in the speaker.
So I unplugged things that are not needed for basic machine operation: fluorescent lights, topper, back lit controller, printer, etc.
Added them back one by one until I heard the noise, took me a while waiting for machine to boot each time.
As soon as the machine was up with the back lit controller I heard the buzz.
I undid it and finished adding everything else back.
No Back lit controller no buzz, Back lit controller buzz is there.
The only thing I have not done is get another ferrite choke for the power harness going to the back lit controller.
I think back lit controller makes so much EFI/RFI that it travels right through the power into the audio section on the MPU and MMLB2

[CaptainHappy]

Is it possible that typically the bad sound coming from the left speaker is a result of the printer being there?  The speaker wire is always sandwiched between the cabinet and the metal frame of printer which is energized.  I recently shopped out a 5-reel MS LGM Vision that was getting a popping sound in the left speaker.  I found the speaker wire wrapped around the power cable that went to the printer.  After I unwrapped and seperated the cables the popping was significantly reduced and less frequent.  Then installed the 47 ohm resistor and had perfect sound.

Also, when you changed out the amp before, is it possible that you had the volume up high to compensate for an amp that was going bad?  So when you installed a new amp it pushed the sound signal at full strength resulting in the loud noise distortion from your speakers.  Now that you have the resistors installed, I would suggest changing the amp out again with the volume set to 6 before you make the swap.

Wires were pretty clear, and I seperated them even more drastically and there was no change. The left speaker wire was going over the top of the printer near the front, not along the back wher the printer power and connections are.

I just got this machine, and sound was initially set on 2, and game sounds were ok except the loud buzz and humm in the left speaker.
I did the 10 ohm mod on the L & R top speakers, and I have not yet touched the base speaker in the bottom. After this the sound was softer so it was turned up to 6-7-8 range. I could not here the game sounds on the left, but the humm and buzz was lessened considerably. (I later discovered if I unplug the base and right speakers I can VERY faintly hear the game sound on the left speaker. This is still the case.)
I tried changing the amp to one that I had, not noticing that they are a little different, see pictures, and I will attach DOCs on them to a later post. It gave some bad sounds and scared me so I turned it off. Took it out and put the original one in again, and on the reboot the reel behaved weird and slow. Sound was at 6-8 range still. After another power cycle it was giving out the game sound as before and as before the left speaker was having same problem as before.

That was earlier. after reading your post I decided to try the AMP again and there was zero sound at all. I looked it over and noticed something different on one amp as compared to the other! Take a close look at the pictures that I posted on reply #42 at connector J1. On one amp it is reversed compared to the other. I noticed that the latch is on the top on one, and the bottom of the other..... WHY WOULD THEY DO SOMETHING SO IGNORANT?? JUST TO F with people??? I am tired now, super frustrated, and I can't really tell if they changed the layout on the PCB to keep the signals for pins 1, 2, 3, &4 matching with the cable from the machine. Or did they reverse it to kill it??? I looked at the schematics that I have attached, and if I read it correctly, they have kept the signal going to the correct pins even with the layout change, but I am not sure anymore as the frustration meter is pegging at max. I also determined theat teh chip at U1 is totally different, and so is alot of the component layout. (It is obvious if you look at the big caps one the sides of U1 as an example. See Picture!) The U1 is the audio power amp chip and it is a Phillips TDA8567Q on the 76928000 board, and it is 35Wx4, and on the other board is a Phillips TDA7454 on the 76924502 board, and it is 25Wx4, so things are definately different.

Anyone ever notice differences in the AMPs like this? I have attached ASSY Drawings and Schematics to this and the next post since it is 4 files.

NOW I am temorarily back to the un-modded state as I clipped the wire on one side of each resistor and bypassed the resistor. Sound on the right is nice at volume of 2 again in "un-modded" state. Sound in left speaker suped low, basically not hearable unless all else is off so you can hear only that. SO has the AMP gone bad, or is there something else wrong with the machine now???

WHERE DO I GO FROM HERE? BRAIN HURTS RIGHT NOW!    MAYBE THE INFO I PROVIDED WILL HELP? Thanks to everyone for their help?

CaptainHappy