Is there a commercially available audio cable with a built-in blocking cap?

Hi,

I've seen a lot of folks makeup cables to feed mono sources (mics) into mini
TRS stereo inputs on camcorders. Hosa makes one, but it doesn't include the
blocking cap that blocks the bias voltage some cameras put out.

Anyone seen a premade cable with a XLR-F pin 2 that feeds both tip and ring
of a 1/8" TRS that also has a blocking cap?

Regards,

Ty Ford



-- Ty Ford's equipment reviews, audio samples, rates and other audiocentric
stuff are at www.tyford.com

 

http://www.trewaudio.com/catalog/items/item276.htm

but ask them to make it right angle
they have mono as well

 

Shure makes one as well. It also has a transformer. Kind of wish they
made one without it.

http://www.bhphotovideo.com/bnh/con...s&Q=&sku=154878&is=REG&addedTroughType=search

 

Markertek appears to sell one: Part# XLF-H8-10 $49.95
"TecNec Pro XLR Mic To 3.5mm Mini Cables for DV Cameras"

"TecNec's exclusive mic cable design with on-board electronics
allows prosumer camcorders to interface with professional
microphones. Blocking capacitors built into the cable eliminate
the 6-volt DC found on camcorder mic input jacks, eliminating
hum. Built with Neutrik XLR connectors and TecNec Mic-BC
shielded audio cable. 10 foot length."

They appear to be charging ~$40 extra to install a DC-blocking
capacitor in an otherwise conventional cable. But it must be
a REALLY GOOD capacitor!

OTOH, my web page appears to be pretty popular for DIY...
http://www.rcrowley.com/CamAdapt.htm

 

marcoleavitt wrote ...

That is just an A-95 transformer connected to a short
cable via the old-fashioned "coaxial-mic" connector.

You can buy a XLR to 3.5mm mini-phone cable in lots of
places. But most of them won't have the DC isolation from
the transformer (or from a series capacitor in the XLR barrel).

I'm not sure that particular transformer is really appropriate
for a Lo-Z to consumer camcorder application, anyway.
The unbalanced (output) side of that transformer is Hi-Z
(like 40-50Kohms) which is a poor match with the Lo-Z
input impedance of the average camcorder (likely 5K or
lower).

 

Look at the Rode site...they make one for their Video mic.

http://www.rodemic.com

 

That's also been my experience.

Ty Ford


-- Ty Ford's equipment reviews, audio samples, rates and other audiocentric
stuff are at www.tyford.com

 

I only point it out because it does indeed block DC voltage.