EHX - Deluxe Memory Man (SAD 1024A) EH7550 [schematic]

[uncleboko]

It's a thermistor.

Similar to the one used in the Polyphase!

[Dirk_Hendrik]

This unit works perfectly but I have an audible whine that decreases in frequency when the delay time is enlarged.

Is there a way to eliminate this? Would adding a balance trimpot to all the SAD's help?

Might pretty well, althought the whine mans that the output filters cutoff frequency is higher than the BBD clock.

Other than that I've modified one of these units once so all BBD sections have their own input bias trimmer. Makes a world of a difference in (lack of) grainyness.

[Bernardduur]

This unit works perfectly but I have an audible whine that decreases in frequency when the delay time is enlarged.

Is there a way to eliminate this? Would adding a balance trimpot to all the SAD's help?

Might pretty well, althought the whine mans that the output filters cutoff frequency is higher than the BBD clock.

Other than that I've modified one of these units once so all BBD sections have their own input bias trimmer. Makes a world of a difference in (lack of) grainyness.

Don't they already have that? Or you mean the second part of the SAD?

[Bernardduur]

The whine is totally gone. I fixed it with two changes:

- The whine on the delay was fixed with 3 extra balance trimmers
- The whine on the rest of the signal was fixed by adding a relais. The switch was too close to the origin of the whine thus it bleeded to the signal.

Sounds pretty nice!!