# Ibanez AD-9 Problem



## KujaSE (Jul 30, 2006)

I tried the delay and hated it when I got it in a trade, so I've been trying to sell it. I plugged it in today to try it out but before I sell it, I'm thinking there's an issue.

When I've got it running from the Dry Out, clearly there's no effect whether the pedal is engaged or not, but the pedal volume is normal, as if I were plugged straight into the amp.

However when plugged into the Out jack, there's a huge drop in volume, and an ever present extremely high (almost hard to notice) ringing. The delay itself works fine, but the volume drop and ringing are issues I don't want to palm off on someone else.

Any thoughts on what it may be, and if it's a simple fix or not?


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## mhammer (Nov 30, 2007)

I suspect the ringing is a misadjustment of the max delay trimpot, which is 2k and I think is labelled R34. This can be confirmed by adjusting the delay time control. If the ringing disappears when you set the control to a shorter delay time, then that's what it is. If so, then the solution is simple. Set the delay time to max delay, and gently tweak the 2k trimpot until the whining goes away.

It is normal in analog delays to have a balance between max possible delay and max bandwidth. If you aim for too long a delay, then you have to either set the filtering at a lower frequency (duller delay sound), or put up with the whining from insufficient filtering at longest delay.

Since you got it in trade, it is possible that the previous owner had heard something about tweaking the trimpot to get more delay time, not realizing what the penalty would be. A little knowledge is a dangerous thing.

There is also a 10k trimpot at the output of the MN3205 chip which balances out the two paths of the delay chip. Minimum clock whine is heard when the two outputs are balanced 50/50. Possible that the trimpot is budged from the 50/50 position.

No idea what the volume drop is from though.

NOTE: All those trimpots can be monkeyed with without destroying the pedal. You might end up with bad tone, though, so mark off where the trimpots started before adjusting them.


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