Crumar Musical Instruments User Group.

Hello,
I was given a non-functioning Bit One by a friend and had it repaired at Main Drag Music in NYC.  It took them a while (and several attempts) to figure it out but they eventually got it going and i tested it in the shop.  All of the presets were wiped and when i got it home i found someone who had posted a .wav file of the preset-restore tones.  I followed the instructions and fed the tones into the synth only to have it completely stop working!  Now i can't get any sound at all out of the synth, except that at some point the synth started "burbling" some strange noise (without me even touching it) for a couple of minutes and then stopped. I can't seem to get it to make any sound at all now.  Does anyone have any suggestions??  This synth has been a heap of trouble so far and i'd love to finally figure out how to get it going....Thanks Alot!!!
Josh

Can you verify that the sounds loaded correctly? Do you get a 0 (zero) after the program load? Other results including a 1, 2, or 3 means it didn't load correctly (for reasons stated in the manual). If the program data is loading without error, and something has failed since the service was performed, it sounds like it needs to go back to the shop.

If it goes back, hopefully you can provide them with the preset sound data, manual, and schematics files. Please note there are two versions of the schematics depending on the version of Bit that you have (early/late - can be identified by filter type SSM vs CEM) - if in doubt, bring both sets of schematics.

You may also want to test then offer some specific instruction on loading the sounds correctly. In my case, I'm using a portable MP3/WAV player, which will only load sounds if set at a very specific volume level. It can be tricky to match the exact level of a tape deck line output that the Bit is expecting. If I have to get one of my Bits serviced, I'll have to make sure they can load sounds without too much hassle.

For the repair shop to consider, a few things that helped me identify problems on my Bits were:

1) ICs operating at much higher temperature than the others (to be tested with a heat probe and definitely not one's finger). In my case many of the failed op amps were running 20-50 degrees hotter than the rest.

2) ICs or Voltage Regulators with incorrect voltage on specific pins (data sheets for such parts would have to be downloaded for comparison)

3) Dead filter chips - these can be identified by holding down six notes at once. For each key that doesn't make a sound, there is a voice that is not working, which may indicate a dead filter. I socketed my filters so they could be re-arranged (or placed in one at a time) to identify the bad ones.

4) Power supply - correct output voltages should be verified

See the Files section here for any documentation that you may need.

Hope you get it working again soon!

I have some experience in loading WAV memory dumps into KORG POLY 800s. (In fact, I sell a complete set of instructions and wav files on my website, but that's another story..)

The Number ONE problem here is the volume level. I think my record is something like 20-30 attempts to get the volume level right..
It's a pain. But worth it. Oh, and cryptic status messages, due to restricted displays. Grr.... 

Someone asked me whether they should replace the battery as well, last week... Jeez. As soon as they switched off, after spending god-knows-how-long loading the sounds, they were lost. I'd though that would have been obvious. Every time I think I've made the instructions idiot-proof, along comes a bigger idiot. 

--- In crumar@yahoogroups.com, "neurokrash" <spamkiller@...> wrote:

>
> Can you verify that the sounds loaded correctly? Do you get a 0 (zero) after the program load? Other results including a 1, 2, or 3 means it didn't load correctly (for reasons stated in the manual). If the program data is loading without error, and something has failed since the service was performed, it sounds like it needs to go back to the shop.
> 
> If it goes back, hopefully you can provide them with the preset sound data, manual, and schematics files. Please note there are two versions of the schematics depending on the version of Bit that you have (early/late - can be identified by filter type SSM vs CEM) - if in doubt, bring both sets of schematics.
> 
> You may also want to test then offer some specific instruction on loading the sounds correctly. In my case, I'm using a portable MP3/WAV player, which will only load sounds if set at a very specific volume level. It can be tricky to match the exact level of a tape deck line output that the Bit is expecting. If I have to get one of my Bits serviced, I'll have to make sure they can load sounds without too much hassle.
> 
> For the repair shop to consider, a few things that helped me identify problems on my Bits were:
> 
> 1) ICs operating at much higher temperature than the others (to be tested with a heat probe and definitely not one's finger). In my case many of the failed op amps were running 20-50 degrees hotter than the rest.
> 
> 2) ICs or Voltage Regulators with incorrect voltage on specific pins (data sheets for such parts would have to be downloaded for comparison)
> 
> 3) Dead filter chips - these can be identified by holding down six notes at once. For each key that doesn't make a sound, there is a voice that is not working, which may indicate a dead filter. I socketed my filters so they could be re-arranged (or placed in one at a time) to identify the bad ones.
> 
> 4) Power supply - correct output voltages should be verified
> 
> See the Files section here for any documentation that you may need.
> 
> Hope you get it working again soon!
>

-My cem3328 version keeps losing it's patches but the battery looked good.  Kind of a pain to have to load them every time I want to use it.  hehe.  Need to figure that out some day.  Great sounding machines for certain types of sounds.  

-Bob

I too would like to know what causes this.  My Bits used to hold onto their sounds for a few years, now I'm lucky if they last a few weeks.

Cheers