RE: [Harp-L] impedance



Dear List, Paul
I own a Shure 520D, which I bought about 25 years ago. I had it rewired to
XLR (following the list for a while I assume that wasn't very smart, but
then I thought I had to feed it directly into the mixer) but I also
purchased a XLR to 1/4 plug adaptor then. Result: I can use it both ways. It
works fine with an amplifier but also with a mixer. Today I have it mainly
connected to my amp. Should I get it rewired it to a 1/4 plug? The
documentation for the newer 520DX writes: "NOTE: The 520DX can be rewired
for low impedance, but this disables the volume control." Doesn't the XLR to
1/4 plug adaptor have the same effect?

Tom 

-----Original Message-----
From: harp-l-bounces@xxxxxxxxxx [mailto:harp-l-bounces@xxxxxxxxxx] On Behalf
Of Paul Bowering
Sent: Tuesday, July 11, 2006 7:01 PM
To: harp-l@xxxxxxxxxx
Subject: Re: [Harp-L] impedance 


Generally mics with 1/4 plug are high impedance and
mics with XLR connectors are low impedance. Be aware
that there are any number of exceptions.

For you as a harp player it isn't a matter of one
impedance rating being better than the other. The
important thing is to match the impedance of your mic
to whatever you are plugging it in to. A mis-match of
impedance will rob you of power and prevent the mics characteristics from
shining through. The greater the difference the worse the problem. Now, you
don't have to match exactly although the closer the better.

Here's the deal; a mic rated in the 150-600 ohm range
is considered low impedance. Plug these into a PA and
you're good. A high impedance mic (in the 10000 ohms
range) can go directly into an amp or effects pedal
because they also have higher input impedances. If you
wish to use components with different impedances you
need to buy an impedance matching transformer and
insert it between them in the signal chain.

I'm far from experienced in this. My second mic, an
e-bay purchased RE-10 arrived last night. I used an
adaptor without a transformer, plugged into my amp
and, besides hum, got nothing at all . I'll have to go
shopping tonight. Recommendations for an inexpensive transformer anyone?

Paul

__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com 
_______________________________________________
Harp-L is sponsored by SPAH, http://www.spah.org Harp-L@xxxxxxxxxx
http://harp-l.org/mailman/listinfo/harp-l






This archive was generated by a fusion of Pipermail 0.09 (Mailman edition) and MHonArc 2.6.8.