[sdiy] Re: About this LC filter formula questions

[harrybissell]

The biggest problem is keeping the main audio path in the hose... not through the
walls of the hose. I had a lot of trouble with the coils of hose touching each
other...
forming a sneak path.  It was big and it was sensitive to external noise as well...

not too practical.  Easy to see why the idea is abandoned.  My hose was 3/8" ID
(garden hose)... I used a compression driver and a dynamic microphone (electrets
were not 'invented' yet :^)

BTW I heartily recommend the BBD as a better DIY vehicle for delay, compared with
the coiled hose method...   H^)

I was thinking of a 4" PVC sewer pipe buried the length of my property... with a
small
electric train moving a microphone into various positions....   :^P

H^) harry

Ken Stone wrote:

> There is a half built one in my workshop at the moment. For a workable echo,
> you need 20 metres of hose. I ahve 40, with multiple taps using electrets
> set in T-pieces. To top it off, there is also a set of reeds being excited
> by the same speaker, which should produce some interesting "resonant responses"
>
> This method has been around for ages. Shcober Organs tried it before
> settling on tape loops. The Time Cube is a commercial example, and numerous
> experimentors have built their own.
>
> Ken
>
> >
> >Here's a freaky idea:
> >
> >Build a "tube echo" with a large length of flexible plastic pipe, which has
> >been rolled into a coil. Connect one end to a small box which contains a
> >speaker. At several points along the pipe, drill a small hole and insert an
> >electret microphone into the hole. Connect preamps (probably with some EQ)
> >to each microphone. Then use your scanning circuitry to sweep back and
> >forth among the various microphone signals. In other words, do the whole
> >delay line with sound instead of an electrical transmission line simulation.
> >
> >How's that for an unusual vibrato-chorus design?
> >
> >One thing's for certain, it's sure to have an "analog" character to it.
> >
> >
> >later,
> >Glen Berry
> >
> _______________________________________________________________________
> Ken Stone   sasami at hotkey.net.au
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