So I’ve just installed my after pressure/LHC upgrade and VX-351 output adapter, and I couldn’t help noticing all of the LM13700s on the Voyager board.
I’ve also just got a Korg Delta for a moderate price, but it is not fully functional. Basically, the String section works, while the Synth section does not. All keys sound, so hopefully the top octave generator/divider are both okay. A little Googling reveals this diagnosis is indicative of one or more faulty LM13600 OTAs. And when I examine the board, I notice one of these has already been replaced, because the markings on the chips are different.
Questions:
Is there another explanation for the Delta’s fault?
Does anyone have a (free) schematic?
Are 13600s available anywhere?
Are 13600s less reliable than 13700s?
Is a 13700 suitable to replace a 13600 in a Korg Delta?
Thanks
Andy
Is there another explanation for the Delta’s fault?
There’s many possible reasons.
I would offer that novice techs often look to components first and not physical connections though.
Many times problems are due to cracked soldering, connectors and other non-component sources.
Does anyone have a (free) schematic?
Not I. Sorry.
Are 13600s available anywhere?
No, but they’re available around if you look.
Are 13600s less reliable than 13700s?
Probably not.
They have one additional transistor inside, but they’re not any more or less reliable on the whole.
Is a 13700 suitable to replace a 13600 in a Korg Delta?
One can usually replace a 13600 with a 13700 and vice-versa.
They’re the same pinout.
13700’s can be very slightly better in some applications, but generally it’s not a big thing.
Thanks KL, I’ll go over the board with a multimeter first.