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Multi-Tap Delay and Feedback

10/9/2002 10:41 PM
LeiterMulti-Tap Delay and Feedback
This may only be new to me, but it’s cool.  
There are two ways to set up feedback in a multi-tap delay: take feedback only from the last tap, or take it from all taps. Until recently, I had only used a digital multi-tap delay that does the first—it repeats the same rhythmic figure over and over.  
I just got a Space Echo, and I think one reason it sounds so great is that it takes feedback from all of the heads. This means you get more scatter in the repeats. You also get “redundant” repeats. Like, if one head is at 0.3 second and one is at 0.7 second, you get a repeat at 1.0 second that is a combination of two repeats: the 0.7 s “second repeat” of the first 0.3 s repeat and the 0.3 s “second repeat” of the first 0.7 s repeat. The repeat at 2 seconds is a combination of 6 redundant fourth repeats, and the repeat at 3 seconds is a combination of 20 redundant sixth repeats. This means that, with two heads, runaway echos begin at 50% feedback, instead of at 100%. (If feedback is at 70%, for example, the fourth repeat is 70% to the fourth, or about 24% of the original amplitude. But six of these add up to more than 100%, and the echo is in runaway. In theory, if the feedback is just above 50%, the echoes should die away and then build up again 10 or 20 seconds out.)

Skreddy Yeah; that wacky multihead mode is ... -- 10/10/2002 2:54 AM
Mark Hammer The A/DA Stereo Tapped Delay (STD-1... -- 10/10/2002 8:45 PM