Re: [Harp-L] Low Z mics - Transformers

[IronMan Mike Curtis <ironman@xxxxxxxxxxxxxxxxx>]

On  Apr 2, 2005, at 9:27 AM, AV1901@xxxxxxx wrote:

> I've never had much luck using a low-Z mic through a "guitar" amp, in 
> part  I
> think because of the cheap piece of #*$!?" no name low-Z to Hi-Z 
> converter I
> picked up in an electronics shop a few years back.
>
> Anyone have a good recommendation for a good quality piece of 
> equipment  that
> will do the job right?
>
> Thanks.
>
> Andy Vincent


You get what you pay for.  Toss the cheapie and get a Shure A95U or 
A95UF (depending on your connector requirements), if you can find one.  
 They used to offer a transformer kit with lots of different adaptors 
that would cover just about anything you'd ever run across.  Shure also 
has a cheaper model, A85F, but I've never tried it and can't vouch for 
its quality.

Also, don't go by connector type.  Make sure your lo-Z mic is on the 
lo-Z side of the transformer, and the hi-Z goes to the amp.

These can also be used with super-high impedance crystal or ceramic 
mics  (e.g. Astatic JT30, Hohner Blues Blaster, etc.)  The mic goes 
into the transformers hi-Z, and the transformers lo-Z goes to the amp.  
Even though the amp is theoretically high impedance, it's much lower 
than the mic's super high impedance.  The MC151 spec sheet lists 
impedance as "equivalent  to a 390 pF capacitor".  The higher the 
impedance the mic sees, the better the bass response, phase response, 
and overall sound quality.



-IronMan Mike Curtis
http://www.IronmanCurtis.com
http://www.SouthlandBlues.com