I got an answer from Yamaha regarding the upgrade: -------------------------- Hi, I found some information about this: PRODUCT: MU100/MU100R/MU100B SYMPTOM: When the PLG150PF is installed, stereo output is expected, but output is monaural. MODIFICATION: Main ROM version is updated from V1.09 to V1.11. PARTS REQUIRED: Part No.XU507200 (V1.11 MASK ROM) The required part (XU507200) is discontinued and therefore not possible to order anymore. With some luck, it could be worth checking on Ebay/other online dealers that sometimes have old stock of spare parts available. Hope this could be of any help! Best regards, Xxxx -------------------------- There are 1.11 ROMs available online but they are all for the MU100R (The rack version). The MU100 also has a 42 pins socketed ROM (reference XT71420 (c) 1997 YAMAHA - mine was version 1.05), but I found the binaries for both and I can confirm that the 1.11 version for the MU100 and MU100R are binary incompatible, so use the right one!
I bought the PLG150-AP board instead of the PF and that works in stereo as normal in my MU100R rackmount synth. I also have the VH, VL, DX, AN, DR boards and they work normally too in my three other MU100R rack synths. So maybe the problem only affects the PF board?
I have owned a few broken MU100R rack synths with the exact same noise fault, and I had my first one bought in 1997 repaired twice under guarantee and it failed weeks after each repair. I think maybe the main large processing chip had either a design or manufacturing fault. The broken ones can still be used to host PLG boards, and the FX features, audio inputs and XG300B mode can be used without problems too.
It still think it's a soldering issue: I did a test where I had the MU100 with the feet on the top, and let it run for a while, and that fixed the sound. My theory is that these devices were earlier surface mounted components, and contrary to many devices the chips are actually pulled by the gravity, so a combination of heat, bad solder joints and gravity, seem to lead to some bad connections. Just reflowing it fixes the issue... until it happens again.
Not yes, I ordered a more powerful magnifier (my eyes are not what they used to be) so I can examine in detail how the contacts and solders are, when I receive it, I will open the box and properly check all the connections. I also contacted Yamaha to see if they could share the information about the upgrade they were providing to the MU100 these almost 18 years ago :) Crossing fingers!
I have a MU100 with the same problem. This weekend I'll take a microscope and a soldering iron and I'm going to solder the ROM IC 38/39. If there are positive results, I will inform you. (Sorry. This comment should be under your other video about the ROM err.)
@@DbugII Managed to find the cause of the malfunction: microcracks on the contacts of the chip IC38. Then I soldered the IC38 ROMs with a soldering iron - all instrument banks are now played correctly. photos.app.goo.gl/NDv9QL6L975bgdNp8
I don't speak Spanish, and I'm not sure after using Google translate if that was a statement or a question? "Hello I can record the sounds of the plg vl of Yamaha mu100 r in performance thanks"
![[Sound Comparison] Yamaha AN1x vs PLG150-AN](http://i.ytimg.com/vi/yFLC0uZRMW4/mqdefault.jpg)
I got an answer from Yamaha regarding the upgrade:
--------------------------
Hi, I found some information about this:
PRODUCT: MU100/MU100R/MU100B
SYMPTOM: When the PLG150PF is installed, stereo output is expected, but output is monaural.
MODIFICATION: Main ROM version is updated from V1.09 to V1.11.
PARTS REQUIRED: Part No.XU507200 (V1.11 MASK ROM)
The required part (XU507200) is discontinued and therefore not possible to order anymore.
With some luck, it could be worth checking on Ebay/other online dealers that sometimes have old stock of spare parts available.
Hope this could be of any help!
Best regards, Xxxx
--------------------------
There are 1.11 ROMs available online but they are all for the MU100R (The rack version).
The MU100 also has a 42 pins socketed ROM (reference XT71420 (c) 1997 YAMAHA - mine was version 1.05), but I found the binaries for both and I can confirm that the 1.11 version for the MU100 and MU100R are binary incompatible, so use the right one!
I bought the PLG150-AP board instead of the PF and that works in stereo as normal in my MU100R rackmount synth. I also have the VH, VL, DX, AN, DR boards and they work normally too in my three other MU100R rack synths. So maybe the problem only affects the PF board?
I have owned a few broken MU100R rack synths with the exact same noise fault, and I had my first one bought in 1997 repaired twice under guarantee and it failed weeks after each repair. I think maybe the main large processing chip had either a design or manufacturing fault. The broken ones can still be used to host PLG boards, and the FX features, audio inputs and XG300B mode can be used without problems too.
It still think it's a soldering issue: I did a test where I had the MU100 with the feet on the top, and let it run for a while, and that fixed the sound.
My theory is that these devices were earlier surface mounted components, and contrary to many devices the chips are actually pulled by the gravity, so a combination of heat, bad solder joints and gravity, seem to lead to some bad connections.
Just reflowing it fixes the issue... until it happens again.
@@DbugII I spoke to one of the Yamaha engineers from their repair department back in 1998/9 and they said the same thing about dry solder joints.
@@EgoShredder That really sucks, because from all my half racks, I still think the MU100 has the best all-around selection of sounds. That's life :D
@@DbugII I just sold the broken ones cheap and kept four that were working fine.
Thank.
Useful information.
You managed to eliminate IC 38,39 ERR?
Not yes, I ordered a more powerful magnifier (my eyes are not what they used to be) so I can examine in detail how the contacts and solders are, when I receive it, I will open the box and properly check all the connections.
I also contacted Yamaha to see if they could share the information about the upgrade they were providing to the MU100 these almost 18 years ago :)
Crossing fingers!
I have a MU100 with the same problem. This weekend I'll take a microscope and a soldering iron and I'm going to solder the ROM IC 38/39.
If there are positive results, I will inform you. (Sorry. This comment should be under your other video about the ROM err.)
@@furtovin Thanks!
If you see something fishy, could you take some close-up photos, so other people can know what actually look for?
@@DbugII Yes of course.
@@DbugII
Managed to find the cause of the malfunction: microcracks on the contacts of the chip IC38.
Then I soldered the IC38 ROMs with a soldering iron - all instrument banks are now played correctly.
photos.app.goo.gl/NDv9QL6L975bgdNp8
Ola puedo grabar los sonidos del plg vl de Yamaha mu100 r en performance gracias
I don't speak Spanish, and I'm not sure after using Google translate if that was a statement or a question?
"Hello I can record the sounds of the plg vl of Yamaha mu100 r in performance thanks"