Line level vs instrument level EDP etc

["William R. Walker," <chillyb@cruzio.com>]

I've read many comments from edp, jamman and rptr users complaining about
interface issues with instrument level sources (ie guitar amps etc). I
recently did a routing consoltation with a looper friend of mine who has an
edp, a repeater, and  a dl4.
all running through a small mackie board. What I noticed with the edp is
that it does'nt seem to have very high input head room, so one must keep an
eye on levels going into it and keep the input volume down, to avoid
clipping. In order to get the signal back  up hot enough, one must in turn,
bring up the output volume, which will naturely increase the noise. This
was not a significant amount of noise, my old jamman has a similar lack of
headroom.  However, if you were to plug your edp, or jamman, or repeater
directly into the front of a guitar amplifier, yikes, watch out! Much hiss
and noise will insue. The solution would be to place some kind of
transformer/line level shifter between the instrument and thelooper, and
the looper and the amp. You want to step up the signal from -10 to +4 going
in to the  looper, and step it back down comming out of the looper in to
the amp. Ebtech makes such a device (or made, in the current economic
climate, I'm not sure who is in business any more). The device is called a
line level shifter, and it will bump a -10db signal up to a +4db signal or
vice versa. very handy tool that will keep noise at bay. The unit is about
the size of a large direct box and they do make a multiple input rack mount
version as well. I know I've posted such info before, but I thought I'd run
it by  again for the newbies.
Bill