High & Low Impedance In same cord?

Bob Branstetter · #1 07-27-2007, 08:39 AM

Is there such a thing a mic cord/cable that contains both high and low impedance wires within the outside casing? The reason I ask is that I mix an AMT mic with a FC pickup and I would like to eliminate one of the cords if possible. Is this possible or practical?

**Chris Fitzgerald** · #2 07-27-2007, 09:23 AM

Possible, yes. Practical? Depends on what you call "practical". I'm embarrassed to admit this, but I was such a tone junkie about 5 years back that I once bundled three cables together: one went to a Trinity mic, and the other two went to the left and right sides of a two sided wing pickup system.

Hello, my name is Chris, and I'm a cross addicted tone/gear junkie.

(Hi, Chris...)

The only way I could figure out how to do it at the time was to go to Radio Shack and buy some of that strange black cable bundling stuff that you have to wind around your cables. It worked fine, but was kind of a pain to wind up afterwards. If you do this, make sure that your cables are exactly the same length. I'm sore it would be possible to build or have built a custom cable for the same purpose, though.

clink · #3 07-27-2007, 10:00 AM

I may be totally wrong on this one.
Why couldn't you use something like Canare Quad cable. Run two wires to the mike and tie the other two together to the hot tip on the 1/4". Split the ground (or solder a jumper to ground the balanced and run a jumper to the 1/4" ground. They ground at the amp anyway.
Heck, on the bass and amp ends make short Y's and dress the connections with heat shrink.
I really think you could get by with running the signal in one of the internal wires. How this might affect capacitance/resistance I don't know.

drurb · #4 07-27-2007, 10:29 AM

Quote:

Originally Posted by Bob Branstetter

Is there such a thing a mic cord/cable that contains both high and low impedance wires within the outside casing? The reason I ask is that I mix an AMT mic with a FC pickup and I would like to eliminate one of the cords if possible. Is this possible or practical?

The two devices you mention do not require cables of different impedances. The same type of cable that works for your mic would be fine for the FC. clink's suggestion seems quite practical although, depending upon how you have the AMT wired (XLR or phone plug) will determine how those internal wires should be split up. One does not have to use "fancy" cable. There are multiple conductor shielded cables available from any good electronic supply house.

Bob Branstetter · #5 07-27-2007, 10:45 AM

Quote:

Originally Posted by Chris Fitzgerald

The only way I could figure out how to do it at the time was to go to Radio Shack and buy some of that strange black cable bundling stuff that you have to wind around your cables. It worked fine, but was kind of a pain to wind up afterwards. If you do this, make sure that your cables are exactly the same length. I'm sore it would be possible to build or have built a custom cable for the same purpose, though.

I have already tried that approach, but I really wanted to see if I could get one normal size cable with just the ends separate (about 6" or so) into the required plugs. The way I have things setup now, the length can be pretty close to being equal.

Bob Branstetter · #6 07-27-2007, 11:01 AM

Quote:

Originally Posted by drurb

The two devices you mention do not require cables of different impedances. The same type of cable that works for your mic would be fine for the FC. clink's suggestion seems quite practical although, depending upon how you have the AMT wired (XLR or phone plug) will determine how those internal wires should be split up. One does not have to use "fancy" cable. There are multiple conductor shielded cables available from any good electronic supply house.

The AMT uses a (plastic) Switchcraft EN3 connector from the mic to the preamp black box. It has 3 wires/pins and a 4th pin that is bridged to another pin to act as an on switch when plugged into the box. I've thought about changing that to a mini XLR, but I've never really hand a problem with the plastic connectors like some others have. So... are you saying that it doesn't make any difference if one is high impedance and the other it low? They would be shielded from each other? Sorry, electronics is not my specialty.

Greg - How would you like to come over and wire this up for me?

**Chris Fitzgerald** · #7 07-27-2007, 11:53 AM

Quote:

Originally Posted by Bob Branstetter

I have already tried that approach, but I really wanted to see if I could get one normal size cable with just the ends separate (about 6" or so) into the required plugs. The way I have things setup now, the length can be pretty close to being equal.

I can dig it. The wild card is going to be that strange 3-pin AMT cable. Other than that, what you're talking about is akin to a simple two channel audio snake cable. You might check at some place like Markertek to see if they have 2 or 3 channel snake cables. With one of these, you could likely solder the 1/4'" and AMT ends in place to pretty much do what you want. Good luck!

clink · #8 07-27-2007, 11:59 AM

Quote:

Originally Posted by Bob Branstetter

Greg - How would you like to come over and wire this up for me?

Bob, I feel a Barter transaction coming on

.

I like Chris's idea.

clink · #9 07-27-2007, 12:05 PM

http://www.markertek.com/SearchProdu...f=59&sort=prod

Chris, is this what you mean?

Uncletoad · #10 07-27-2007, 01:30 PM

The wire from the mic to the super pre is proprietary. I changed mine out by running the phantom down a 4 pin XLR instead of that stupid thing they provide.

Because of the use of all four of those pins you can't add another signal on a cable unless you find some 5 or 6 pin connector.

It's a big mess they made there.

drurb · #11 07-27-2007, 01:40 PM

Quote:

Originally Posted by Bob Branstetter

...So... are you saying that it doesn't make any difference if one is high impedance and the other it low? They would be shielded from each other? Sorry, electronics is not my specialty...

Correct. The cables themselves do not need to be of different impedances and standard shielded signal cable will work for both. They also should not need to be shielded from each other. Both signals would pass through the same combined cable that would have shielding around it to block noise/radio-frequencies/AC/general crud from the outside.

Bob Branstetter · #12 07-27-2007, 01:53 PM

Quote:

Originally Posted by Uncletoad

The wire from the mic to the super pre is proprietary. I changed mine out by running the phantom down a 4 pin XLR instead of that stupid thing they provide.

Because of the use of all four of those pins you can't add another signal on a cable unless you find some 5 or 6 pin connector.

It's a big mess they made there.

I think you are talking about something different than I envisioned. I don't need nor want the AMT & the FC to be on the same plug. I don't have the super pre and I've already swapped out the cable from the mic to the pre when I converted it to a tailpiece mount.

Uncletoad · #13 07-27-2007, 02:10 PM

Quote:

Originally Posted by Bob Branstetter

I think you are talking about something different than I envisioned. I don't need nor want the AMT & the FC to be on the same plug. I don't have the super pre and I've already swapped out the cable from the mic to the pre when I converted it to a tailpiece mount.

Ah.

I'm not clear on what you are trying to do.

flatback · #14 07-27-2007, 03:43 PM

Hey you cats,
Heres what I do: I blend a mic and pickup and run them into a Focus III. I bought about 12 feet of techflex sleeving here:
http://www.techflex.com
and ran both wires thru it heat shrunk the ends and Voila! a single cable with both 1/4" and xlr. I got tired of having two cords getting tangled on the floor and in my bag. The techflex 1/2in black is what i use and it is definitely thicker then just the one but it works for me....

Bob Branstetter · #15 07-27-2007, 06:09 PM

Quote:

Originally Posted by Uncletoad

Ah.

I'm not clear on what you are trying to do.

Basically, I don't want to have to change any of the things I have now. I just want to have one cord instead of two.

fdeck · #16 07-27-2007, 11:25 PM

Full Compass sells bulk "snake" cable by the foot, and it goes all the way down to two individually shielded balanced pairs within an outer jacket. The picture shows more than two pairs, so I assume it is a generic picture for the overall product line.

http://www.fullcompass.com/product/260857.html

You could use one of the pairs for hi-Z, no problem.

fdeck · #17 07-27-2007, 11:27 PM

Otherwise, here you have every possibility:

http://www.mogamicable.com/Bulk/micr...ab/video6.html

Go nuts!

Uncletoad · #18 07-28-2007, 12:50 AM

You can get one of the cables listed above that has at least 5 internal wires and a common overall sheild. I think it could share grounds ok unless you phase reverse the pickup. In that case get one of the cables that has two individually shielded centers and two stranded other lines. That would run the phantom power to from the preamp to the mic, the signal from the mic to the preamp and the full circle passive signal to it's own thing. You'd have two jacks at each end, one that plugs into the preamp with whatever XLR type thing you are using and then a 1/4" shielded breakout for the full circle.

Bob Branstetter · #19 07-28-2007, 09:38 AM

Thanks guys for all of the good advice. I'll let you know later how this all works out. It sounds like it should be possible and practical

Greg - what would you lke to barter?

fdeck · #20 07-28-2007, 01:13 PM

Quote:

Originally Posted by Uncletoad

You can get one of the cables listed above that has at least 5 internal wires and a common overall sheild. I think it could share grounds ok unless you phase reverse the pickup. In that case get one of the cables that has two individually shielded centers and two stranded other lines. That would run the phantom power to from the preamp to the mic, the signal from the mic to the preamp and the full circle passive signal to it's own thing. You'd have two jacks at each end, one that plugs into the preamp with whatever XLR type thing you are using and then a 1/4" shielded breakout for the full circle.

That's a good idea too. In fact, there is quad microphone cable that should be available by the foot. The only danger of sharing a common shield is if you unplug the phantom powered mic, you might get a loud pop through the piezo channel. So be careful, and / or experiment at low volumes before committing.