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BNC plug. The pro audio world uses these for serial digital applications, but they are widely used for video and used to be common in computer networking.

I have been asked this question before, and I think I know what's going on, but...

With unbalanced, standard 1/4" instrument cables, is marketing "shielded" cables just hype? Aren't most or all instrument cables single conductor with a shield where the shield is the sleeve of the connector?

What's the deal?

Malcolm Boyce wrote:I have been asked this question before, and I think I know what's going on, but...

With unbalanced, standard 1/4" instrument cables, is marketing "shielded" cables just hype? Aren't most or all instrument cables single conductor with a shield where the shield is the sleeve of the connector?

What's the deal?

Instrument cables definitely need to be shielded. Perhaps promoting the fact that a specific cable is shielded helps differentiate it from, say, a speaker cable with ¼" plugs.
I'll be honest here, I am not subjected to a lot of marketing hype, so I may be addressing this from a different perspective. There is always the possibility that the "suits" feel that splashing Shielded! across their packaging is a simple way of making you second guess whether the competitions unmarked packing contains a cable with shielding.

It is, as I assumed.

I have basically had people tell me how they spent $$$ for "shielded" instrument cables.

Blame the salesperson.

They are, in fact, all shielded.

Buyer beware, as always.

weatherstation audio wrote:Banana speaker connector... most pro audio power amps of ther past and today have these type of connections, but it seems that the speakon format is slowly taking over.

The bump on the left of this Banana cable connector is the negative connection... in ease of indentifying in the dark, perhaps ?





And the mated version on the power amp chassis.

Dude, where did your images go? Looks like the original site disabled your hotlinks.

@ WSA -
Now your images are back! It's the work of wizards, I tell's ya!!

Is there a difference in the quality of shielding used in 1/4" cables? And what are the different types, I mean is one type better than another or are they all pretty much the same?

josh porter wrote:Is there a difference in the quality of shielding used in 1/4" cables? And what are the different types, I mean is one type better than another or are they all pretty much the same?

There are definitely differences.
The 3 main types are braided, spiral, and foil.

The quality can vary, and is typically expressed as a percentage, with 100% being the best.

- Foil gives you 100% shielding, but is not ideal for portable usage. Typically found in installation cable, due to lower cost.

- Spiral copper is commomly associated with lower percentages, and cheaper cables, but Mogami makes most of their cables with spiral shielding, claiming longer life in flexable and portable applications.

- Braided copper typically has the best percentage for portable applications, but the strands tend to break after repeated flexing, resulting in noisy cables.

what about the materials used to make the shield? i have two, carbon shielded cables and 5 copper shielded cables. is there a difference in preformance or not?

josh porter wrote:what about the materials used to make the shield? i have two, carbon shielded cables and 5 copper shielded cables. is there a difference in preformance or not?

Ahhhhh...I knew we were gonna get down to this.
Most likely, the carbon shielding refers to a conductive carbon impregnated sheet that is located between the outer copper shield, and the inner conductor dielectric. It provides 100% shielding for copper shielded cables.
If this is the case, then the carbon cables are the better choice.

I can't say that I've ever seen a cable using only the carbon sheet, but I don't know everything, either.....

Link -

http://www.canare.com/index.cfm?objecti ... 4EA6821ADA

Getting back to basics, I previously mentioned that pin #1 on an XLR connector is "shield".



Well....

It is ALWAYS shield. I do not know of any exceptions.
Pin #2 is almost universally accepted as the "hot", or postive connection, while pin #3 is "cold" or negative.
....and "yes", the pins on the connector are numbered.
If you are merely making a straight-through patch cord, the assignments of pins 2 and 3 is immaterial, as long as your wiring is consistent from to end.

Exceptions to this rule in the next post....

QSC and Carver were notable exceptions to the "pin 2 hot" rule, and to the best of my knowledge, Peavey still is.
Their wiring convention calls for "pin 3 hot", which means that in a mixed component system, there is a very real possibility of ending up this signals which will be out of phase.
Phase relationships pertaining to audio can be dealt with in another topic, if anybody asks me to. There are better qualified peeps on this board to explain it, too.

oddioguy wrote:QSC and Carver were notable exceptions to the "pin 2 hot" rule, and to the best of my knowledge, Peavey still is.

I have run into a quite a few British pieces that were the same, some old Drawmer, as well as some Allison Research/Valley People gear.
Sometimes it's difficult to say if it was shipped as such or modded to fit in a given scenario by a tech.

Neutrik has fairly recently introduced a "Silent" phone plug. THe idea has been around for many years, but this is the best one that I have encountered.
Eliminates that annoying and potentially harmfull POPwhen you unplug with your amp cranked to 11.

U1176 wrote:

oddioguy wrote:QSC and Carver were notable exceptions to the "pin 2 hot" rule, and to the best of my knowledge, Peavey still is.

I have run into a quite a few British pieces that were the same, some old Drawmer, as well as some Allison Research/Valley People gear.
Sometimes it's difficult to say if it was shipped as such or modded to fit in a given scenario by a tech.

Most likely someone wanted to integrate their classic Drawmer with their top-end Peavey system.



Seriously though, "pin 3 hot" does sound very British when you think about it.

I read somewhere one time that all 'Shure' mics were wired out of phase (pin 3 - hot).
Can you confirm/deny this?

...Jef...

Jef wrote:I read somewhere one time that all 'Shure' mics were wired out of phase (pin 3 - hot).
Can you confirm/deny this?

...Jef...

First things first...

Welcome Jef! Feel free to contribute here. Any and all info is welcome.

To answer the question....whatever you read was written by someone who was misinformed. Shure has always adhered to the AES convention of "pin 2 hot"

oddioguy wrote:

Jef wrote:I read somewhere one time that all 'Shure' mics were wired out of phase (pin 3 - hot).
Can you confirm/deny this?

...Jef...

First things first...

Welcome Jef! Feel free to contribute here. Any and all info is welcome.

To answer the question....whatever you read was written by someone who was misinformed. Shure has always adhered to the AES convention of "pin 2 hot"

Thanks for the welcome there OG. And for dispelling the 'pin 3 hot' myth.
It was a long time ago when I read this and maybe it wasn't 'Shure' mics. Do you know of any of the top brand names that do have their mics wired in that config? maybe AKG?

"Any and all info is welcome"
Be careful there..(hehehe) you know I am from the 'old school' of seat-of-the-pants engineering. My methods may be a little unconventional and probably somewhat controversial. Could make for some heated and argumentative discussions here ...

Jef wrote:....(snip)...Could make for some heated and argumentative discussions here ...

But they will educate regardless, and that is the point, my friend!

Jef wrote:It was a long time ago when I read this and maybe it wasn't 'Shure' mics. Do you know of any of the top brand names that do have their mics wired in that config? maybe AKG?

No current microphone models from manufacturers would be made pin3 hot. In fact most did wire pin2 hot before it was made AES standard.

Now, other equipment being pin3 hot... that's a whole other kettle o'fish.

Thanks for that info, Malcolm.
I remember where I heard it now. It was way back in the early 80's and I was attending a seminar on sound engineering that was sponsored by Musicstop in Halifax. The guy hosting the seminar was Bruce Thompson who, at the time, was quite revered in the industry. It was during a discussion on balanced lines and common mode rejection that he mentioned it. I'm sure he said either Shure or AKG.
Even if all the mics that are produced now are in the pin 2 hot config, is it possible that some of the older mics that were built back then could be backwards? Is there any easy way to find out?

My understanding is that you would have to be talking '60s or earlier to see stuff wired pin3 hot, and even then it would be rare. Definately no manufacturer's "standard" was pin3 hot.

The only instance I know of transducers being wired "backward" to standard is JBL drivers being reverse polarity to all others. That's the only thing I can think of where a company was known to have a "standard" that was from opposite world.

Once again, thanks for the info.
Yes I was aware of the JBL drivers being wired out of phase.
OK, OG, you can get back to your connecter discussion.
... got a little side-tracked there...