Yamaha A3000 Fix

[xampla3]

Hi to everyone in the community. I am glad this forum exists and a BIG THANK YOU to all of you , from administrators(s) to members. I have many times found so much useful information that help me expand my knowledge about synths and music technology and tech problems i had at times.

So now it is time for me to offer something little in this forum, as a token of gratitude..
It has to do with the most common problem with the YAMAHA A3000 encoders.

You can read my complete post in my blog:
https://synthnitz.blogspot.com/2019/04/ ... 0-fix.html

The juice of it is that i have found out a design flaw in the support of the encoders themselves, resulting in damaged board (lifted copper traces....). I think i found a remedy for this, but i have not yet completed the fix.
I will keep you informed about how it is evolving. ..............

My best regards to all of you here.

[xampla3]

(MAY 2019 UPDATE)

https://synthnitz.blogspot.com/2019/05/ ... art-2.html

I finally found the time to (almost) complete the task of fixing the A3K. The above link is from my blog with photos.
At this time i am searching to find some nuts to bolt the encoders on the reinforcing plate, but no such luck (yet)..

Anyway, i hope the administrator allows me to post the above link of my blog...

Here are some photos of the final result of the work i've done :





I hope this will be useful to any owners of the Yamaha A3K.
As soon as i fit everything and start fiddling with it, i'll post again.

Thanks for reading.

[xampla3]

Finally, my project is finished ! I ordered the fine-pitch nuts for the encoders, received them and mounted the metal plate to the A3K chassis.

Please read all details here : https://synthnitz.blogspot.com/2019/10/ ... maybe.html

This is the result :




I think the plate did the job right. The encoders now feel rigid when pushed and turned, no wobbly action, and the PCB is probably well protected...
Of course, the skippy action is not eliminated (but this was not the scope of the metal plate, in the first place)..

It still makes me mad that the encoders do not obey my commands !! ,
so it is time to replace them.. Maybe i will choose some other brand (besides Alps), for a change and see what happens..

I hope you can find my posts useful.
Thanks for reading.

[EB5AGV]

Nice job!

Did you use the original encoders or new ones finally?. If the later, which brand and model?

I have also an A3000 with less-than-perfect encoders on it.

Jose

[xampla3]

Thanks for your kind words.
Actually i replaced the whole pcb which had good encoders (as i thought initially, anyway). The board that this A3K had when i bought it used, had many solder traces lifted, and most of the encoders were wobbly (one actually was dismantled !). You can see the pics i took in my blog --> https://synthnitz.blogspot.com/2019/05/

I just cleaned the encoders (these are stock ALPS encoders) with Teslanol spray and played around with them a bit, and also resolder one or two solder joints which showed a cold joint, and then i put it back in the A3K. They work, but you know how!! They have a mind of their own!!

I am thinking of getting a BOURNS similar encoder (PEC11L-4220F-S0015) to test and see if the situation would improve.. Of course there is also a modification with capacitors to improve the encoders precision , but first things first..
For now i will play around and make some music...

[xampla3]

Ok. i finally got the Bourns encoders, BUT i did a mistake and ordered the PEC11LL-4225F-S0015 instead of PEC11LL-4220F-S0015, so this means these are 5 mm longer! So i cut 5 mm off the shaft and they seem to be ok now.
Please read all details here --> https://synthnitz.blogspot.com/2020/01/ ... oders.html
This project seems to last forever , but my free time is limited these days....
Encoders have to be soldered to the PCB, and some testing to be done. So, i;ll keep you informed how this progresses.
Greetings.

[xampla3]

Finally! I completed the A3000 FIX project! Made a final conclusions page that sums it up :
1) Reinforcing plate : works and protects the encoders' pcb solder joints.
2) Encoder selection : i collaborated with another user, and we concluded to a good selection of replacement encoders for the A3K.
3) Separate board with capacitors : i made this according to instructions from another guy's page and it truly works! Encoders now have a night and day behaviour.

You can read the final "conclusions" post https://synthnitz.blogspot.com/2020/02/ ... sions.html.

I hope that all this information will help other users of this amazing sampler to solve things and improve its function.
Greetings to you all.