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[Tom Bourke]

In another auditorium I work with I have to do some rewiring.  The system is only 2 years old and the installers badly skimped on the work.  The stage end of a 40 PR snake terminates in an 18"*18" box where the lines from the floor pockets also end up.  Currently the wires are joined with poor crimps.  I would like to install a punch panel in the box.  But I have heard that punch panels on such small  stranded wire is bad to do and that I should recrimp the proper way or solder the thing.

Is there a proper punch block for snake wire or should I just re-crimp?  I am contemplating a adding a Mass connector to the system so I can feed all mic lines (32 total) with out having to run cables to all the floor pockets.  But I dont thing I can justify the cost for something that may not get used.  Any thoughts on this too?

Tom B

[Hal Bissinger/COMSYSTEC]

While there may be a punch down system for stranded audio wire that was recently introduced since I last looked, most likely you are talking about the 25 pair 66 or 110 type telcom block. These are designed for solid wire and although there are one or two people who swear that they will work with stranded, I suggest that you will have intermittant problems no end.

I would do the best thing possible- cut everything back and start fresh. Resplice using solder and shrink tubing.

-Hal

[Karl P(eterson)]

What your looking for is the MASS Punch system from Whirlwind and ADC go here And browse down the page, its a good system, and much faster than soldering and shrinking all the splices.

Note: You need the punchdown tool, but worth it in the end.

Karl P

[Rick Johnston]

Hal Bissinger/COMSYSTEC wrote on Fri, 25 June 2004 21:36

... most likely you are talking about the 25 pair 66 or 110 type telcom block. These are designed for solid wire and although there are one or two people who swear that they will work with stranded...

I must be one of the two.

Do 66 blocks work with stranded wiring? Absolutely. The key is not to strip the wires before you punch them down. And a quick twist of the shields will allow them to be punched down more easily.

Visit any school. Pay close attention to the MDF behind the main paging system head-end. You'll see countless 66 blocks, some with 18- and even 16-gauge stranded speaker wires punched down. Then visit the auditorium. Chances are, you'll see another MDF behind the amp rack where you'll find a few more 66 blocks. These will terminate the inputs spaced around the stage to the 22-gauge stranded wires in the snake fan.

Many TV stations, radio stations, and theaters use standard telephone 66 blocks to terminate audio lines. I've even used them in recording studios.

Another nice feature versus solder is that you can troubleshoot ground loops by simply removing Pin 1 from one side of the PB (or popping the bridge clip, if you use them) rather than dragging out the soldering iron.

Some of the schools I visit as a field service tech haven't had to have the wiring serviced in 20 years or more. The only time there is a failure with the wiring is when someone who doesn't know what they're doing messes with it.

-- RJ

[Brian Bolly]

If stranded didn't work on punchdown terminations, Whirlwind wouldn't make them, and ADC wouldn't use punchdown terminations on their patch bays.

Perfect example:
http://www.whirlwindusa.com/spl2.html

I wouldn't waste your time with trying to put in a MASS setup for something that doesn't sound like it'll be used for MASS' main purpose...frequent connection/disconnection.

Go punchdown, but make sure you have the proper tool to do it.  It will save you MUCH time and aggrivation.

-Brian

[Karl P(eterson)]

Those punchdowns are special ones designed for stranded use, I wouldn't use standard telco blocks for audio use (some do, I don't subscribe to that camp now that other more suitable products exsist, ala MASS Punch). The MASS Punchdown is a much better choice. And if you were talking about MASS Punchdown when you were talking about frequent connect/disconnect (I can't be certain), I beg to differ. They are intended for permanent type applications.

Karl P

[Brian Bolly]

Karl P wrote on Sun, 04 July 2004 22:59

And if you were talking about MASS Punchdown when you were talking about frequent connect/disconnect (I can't be certain), I beg to differ. They are intended for permanent type applications.

No...he had mentioned putting a MASS connector (a la W3/W4) instead of a punchdown to mate the terminations.  I know very well that no one in their right mind would use a punchdown block for any type of connect/disconnect.  

-Brian

[Karl P(eterson)]

Good! and thanks for clearing that up, I just wasn't sure and figured some others might not be sure as well.

Karl P

[Tom Bourke]

BrianB wrote on Mon, 05 July 2004 07:12

Karl P wrote on Sun, 04 July 2004 22:59 And if you were talking about MASS Punchdown when you were talking about frequent connect/disconnect (I can't be certain), I beg to differ. They are intended for permanent type applications. No...he had mentioned putting a MASS connector (a la W3/W4) instead of a punchdown to mate the terminations.  I know very well that no one in their right mind would use a punchdown block for any type of connect/disconnect.   -Brian

Sorry I did not clarify what I meant.  Right now the only way to get a mic plugged into the system is to plug it into a floor pocket.  There are 4 of them 6 mics each all 10 ft from the nearest wall.  I was contemplating getting a Mass Punch with a Mass connector on the front and then terminating the lines from the floor pocket and the snake to the punch down on the back of it.  Then I would have the option of ether plugging in to the floor pockets or using a single box at  the end of a snake to get all the mics plugged in, or a combination of both.  I have decided to scrape the idea of adding the the w3/w4 end to the stage as I don't see it being used that often.  Instead I will just add some jacks to the side of the steal box so I can plug a mic in with out a cable going to mid stage.

Tom B

[Rick Johnston]

BrianB wrote on Sun, 04 July 2004 22:50

If stranded didn't work on punchdown terminations, Whirlwind wouldn't make them, and ADC wouldn't use punchdown terminations on their patch bays.

Thank you.

The only time I used one, the owner of a video plant insisted on an ADC patch field. Three full man-days and a $75 tool later, it was connected to the audio system. A PB66 would have taken half a day and we already had several tools.

Let's face it: The trend in our industry is moving toward unshielded twisted-pair for line-level signal wiring. Who knows that stuff better than the phone company?