vocoders, OT: ETI/Powertran available in sweden!

[Magnus Danielson]

From: "Bjorn Julin" <bnillson at hotmail.com>
Subject: Re: vocoders, OT: ETI/Powertran available in sweden!
Date: Tue, 31 Oct 2000 00:53:30 GMT

> This might concerna only scandinavians but
> there is a wery good condition ETI/Powertran vocoder
> at the Music shop,musik borsen in Vesteros for
> 3200skr. It looks to have been built at the
> Powertran factory or!!

Possibly, but you could buy the full Vocoder kit including frontpanel
and knobs. Regardless, if it is in good condition it doesn't really
care.

My ETI/Powertrans does not have the Powertran frontplate and knobs.

> >Speaking of vocoders....
> >
> >I have looked all around at the available information on vocoders and what 
> >I
> >have come to understand is that all the vocoders that people praise as the 
> >best
> >sounding have very steep filters (some 54db/oct.) and lots of them. I am
> >considering constructing one, but all the designs I have seen on the net 
> >are
> >for machines with 10 bands or less, and 24db/octave filters.
> 
> Use 24db filters with smaller Q (band width) but mor of channels
> and you get the same effect as you would use 54 db filters.
> 
> Besides 54 db filters are wery difficult to design properly,
> to get stable or what ever!!

Agree. The main benefit of actually doing an 54 db/oct design in my
mind is that you have less phase/impulse distorsion, and this point
would mainly relate to the synthesis and not analysis part of the vocoder.

To the best of my knowledge did only the EMS 5000 contain "full"
filters, but I guess BJ knows this way better than me.

Cheers,
Magnus