View Single Post
  #25   Report Post  
Posted to rec.audio.pro
Linda Masterson Linda Masterson is offline
external usenet poster
 
Posts: 20
Default Star Quad Cable Wiring (Canare)

On 2/8/2018 5:17 AM, Mike Rivers wrote:
On 2/7/2018 9:06 PM, Linda Masterson wrote:

I have two custom made Canare star quad L-4E6S that I had made up
years ago at different lengths, 1/4 "stereo" ;-) male jack to two XLR
but have noticeable hum which was unacceptable although the gain was
cranked up and no preamp gain was used.



There are many reasons why you could have hum, but star quad cable isn't
one. I haven't read the whole thread, so maybe Scott or someone already
mentioned this. Star quad cable, when used as designed, helps to reduce
pickup from electromagnetic fields.


May I clarify, my whole studio is wired with Canare star quad cable and
I have *zero* hum.

However, I have two cables which were custom made with a TRS male
Switchcraft connector to two Neutrik XLRs for exactly like the situation
I have now except it was for a stereo output of an old Fender Princeton
Chorus and I have noticeable hum when I cranked the gain when I hooked
it up to the keyboard. Both cables. Maybe I had some hum back then and
didn't notice at the time. I am cranking gains now for test purposes.

I would like to avoid the direct box suggestion at all cost if
possible and was hoping to avoid this and as Scott brought up, yes
this cable is all I have and I have a bunch of it.


You absolutely don't need a direct box (two for stereo) to connect a
headphone output to a line level input unless you're running a
particularly long cable, like more than about 50 feet. A direct box
gives you a balanced MIC level signal. You'd use one if you were going
into mic inputs on the mixer.


Thanks!

For a long cable run, using a short cable to connect the keyboard to a
direct box and then mic cables (you could use your lots of star quad
cable here) between the direct box and mixer.

I'd recommend an off-the-shelf solution. Buy what's commonly known in
the PA business as an Insert cable. It's a 1/4" TRS ("stereo") plug on
one end and two 1/4" TS ("unbalanced") plugs on the other end, wired
with one TS plug wired to the tip and the other wired to the ring of the
TRS plug. Here's a link to Swee****er's Insert Cable web page. There's
even one with a mini stereo phone plug on one end if your keyboard's
headphone output is a mini jack.

https://www.swee****er.com/c780--Insert_Y_Cables


Yes, in my second post in this thread I showed two links to insert
cables that I have tried with no hum when cranked. I wanted to use my
left over star quad cable which I have a lot of to build a cable.

I have a brand new TRS Switchcraft connector and two Switchcraft TS
which I am trying to find a new home for using my star quad cable for
the Yamaha keyboard output which has a 1/4" stereo out only; consumer
grade keyboard but with good sampled sounds.

I would however like to get my hands on some of this.
http://www.canare.com/ProductItemDis...oductItemID=61


You really don't need any high-falootin' cable. If you have a hum
problem with plain old cable, properly wired, you don't have a cable
problem, you have a ground problem. Maybe a transformer (direct box)
will alleviate it, or your keyboard or mixer may have a problem, either
something broken or a design problem straight from the manufacturer.


I wired all of my my *instrument cable* with mostly short runs as well
using star quad cable and that was done in the day. Canare did not sell
instrument cable IIRC at that time. Sure I could have used other cable
but like I said I bought a ton of this cable to begin with and am still
using it and it is not in every color of the rainbow which they make and
mine are all black except for these two blue Canare custom cables which
are both humming. Continuity tester checks out fine but having 1/4" inch
on both ends solves my hum problem because I checked with (brand) insert
cables.

Questions:

How would you wire this star quad cable like Scott alluded to which I
actually understood? ;-)

Also, should I change out all of my star quad cable made for instrument
cable like guitar and bass with instrument cable? I have not noticed any
signal degradation and zero hum but more testing might be in order.