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previous: Joe Jasniewski I guess this is as good a place as ... -- 8/18/1996 10:26 PM View Thread

Re: Thurston Moore's patented controlled feedback

5/3/1997 7:44 PM
Mark Hammer
Re: Thurston Moore's patented controlled feedback
I recently picked up one of the Boss "Super Feedbacker Distortion" pedals in exchange for a homebrew Big Muff. As far as distortions go, the Big Muff outguns the DF-1 by miles, but the feedback function intrigued me, and I can always throw another Big MUff together on a weekend, so I swapped.  
The DF-1 has one of those cute BOSS switching setups where a quick foot-press latches the distortion effect in circuit, and holding the pedal down longer brings in the (unlatched) feedback function (along with a blinking status LED). This lets the user engage the feedback function for select portions,and disengage it while retaining the distortion.  
The distortion is so-so, as noted, and has a useful tone control that works like the BIg Muff's (honky bass through to insect noise treble). The overdrive has a modest range of voices, and the unit has lots of gain for overdriving subsequent stages.  
Now the main course. The feedback function bewilders me from a design standpoint. It is undoubtedly complex, judging from the sizable component count inside. I can think of various complicated ways to do it, but I have no idea how it gets done in this particular instance. I don't have it here in front of me, but I seem to recall that it will generate an infinitely (at least as long as you press the footswitch) sustaining note at the fundamental, and other harmonics above. I think it does a fifth and an octave. The rotary control pans between these various feedback tones. No other feedback tones are obtainable.  
Unlike conventional acoustic feedback (guitar to amp back to guitar), the DF-1 generate feedback tones at any volume independent of the amp (it can generate feedback tones while playing in your favourite headphone amp). It will also generate feedback even when the distortion is turned down, although it sounds better with the distortion turned up. With an additional distortion unit placed either ahead or after it, the feedback tones start to get interesting.  
In general, with good picking style and a hefty guitar output, the DF-1 will have about an 85% hit rate, in terms of generating feedback tones that are *precisely* the root or overtone of the note played. In this respect, it plays (though obviously doesn't *sound*) like an octave divider. The other 15% of the time the note is either a bit sharp/flat or simply the wrong note. That being said, this thing is NOT a ring modulator cranking out "surprise" notes. Most of the time you can get exactly what you want out of it (I like the way it lets me pretend I'm Jorma Kaukonen).  
It WILL respond to multiple notes (e.g., chords), but will not generate more than one note, and not necessarily one that makes sense, given the chord.  
Although I've used it at low volumes, I have not field-tested it at volumes which are - in themselves - capable of generating feedback, so I can't really say how it either potentiates, or alters, acoustic feedback.  
If you can find one around for $40, I say pick it up. Otherwise, understand that this is not a unit that you can simply turn on and forget about, while you wail away and sound swanky (e.g., like a Univibe). You have to WORK with this thing, and plan out your playing. In that respect, it may be more of a studio gadget than anything else.