Hey all!
I got this Ibanez AD-9 from a guy who said it didn't work; he wanted to throw it away :)
So I tried it........ and it does this weird thing
- On low delay times the delays are still good and crisp
- If I turn the delay time up the delays get distorted to a point the real sound is not noticeable
I thought it was a simple case of adjusting the bias trimpot of the unit but I can't find a place in which she sounds OK; turning the bias pot does make the delays cut out on some max settings, but no clean delays can be heard.
Any ideas????
Some info:
- supply voltage = 8.93V
- voltage over MN3205 = 7.71V
Delay trimpot (2k) is set to 1.20k
Feedback trimpot (20k) is set to 9.62k
Balance trimpot (20k) is set to to the middle position (both sides 11.6k)
My starting place is to measure the pins of the 4558 chip. What are the voltages?
-Zach
Quite OK
I probed the circuit and I lose the signal after the BBD chip
Before it I have good quality
So it has to be somewhere around that stage