[TenTec] EV638 update for Orion

[K8JHR]

A few random ideas ...

I would try to find a data sheet on the microphone that should indicate 
what the transformer does and how it is wired.   I would also scour the 
internet and look for an inexpensive dynamic microphone cartridge to 
wire into it.  I recently "restored"  an old Shure "550"  Unidyne (the 
larger, original Elvis type microphone built in 1947) and used an 
inexpensive dynamic mic cartridge I purchased on eBay for $10.  (I can 
send you photos and a sound sample if you like.)  It turned out swell, 
but I would be tempted to look for a little better one next time.

DATA SHEET --

http://www.coutant.org/ev638/ev638.pdf

More info on it:

http://www.coutant.org/ev638/index.html

THIS MODEL CAME AS HI OR LOW IMPEDANCE - WHICH THE
CUSTOMER SPECIFIED ON ORDERING IT...  So I would
think your idea of converting it may be a good one...
but it may depend on the cartridge, and not the transformer,
and other guts, I am not sure - some microphones use the
same cartridge and use transformers and switches to
change impedance, but others seem to use different
mic cartridges as well, so that needs to be checked, but
think the product data sheets suggest the inquiry is
a good one.


I would not try to fit the odd HEIL HC5 cartridge, myself, as I think 
you can do better for less.   You could buy an inexpensive, maybe used, 
Samson RS10s or something similar and cannibalize it for the cartridge 
within.

Another option is use the high impedance mic with an inexpensive mic 
preamp that would better match the mic to the rig (it would use the 
Line-IN input on the rear of the rig if there is one.)  I sometimes use 
the M-Audio AudioBuddy preamp with my high impedance 1968 vintage Shure 
PE-53 Sphere-o-Dyne microphone and the output of the preamp makes it 
virtually indistinguishable from a more recent low impedance mic.  (I 
can send a sound sample if you like...)

Although I have not fully thought this out... it occurs to me that a 
direct box (DI box) might be used to match it to the rig... or you might 
use an in-line high-to-low-impedance transformer to better match it to 
the rig.  Need to sleep on that idea...

You might also find you are sitting too far back from the mic to get its 
best audio output.  Proximity effects... where you sound more full and 
bass-y up close, and thin and tinny far away, may be causing you to reap 
less than its full capabilities.  Some guys use that mic as a "harp mic" 
cupping it in their hands, with a harmonica, and so you, too, may 
benefit from re-setting the MIC-GAIN after moving closer to it, maybe 
speaking 3-4 inches from it, slightly off access to avoid breathing into 
it, and maybe you will sound better.   Perhaps a number of the above 
suggestions will improve its performance... such as close talking it, 
and inserting an in-line impedance transformer, or running it on a 
suitable preamp, or ... or...

What is the inside diameter (ID) of the mic case that holds the cartridge?

Random thoughts... maybe something will get the click for you.

Happy days.

---------------  K8JHR  --------------------------------

On 8/15/2014 4:30 PM, Bill Ogden wrote:
> I have an Orion 1 and an Electrovoice 638 Hi-Z microphone