the history of speaker wiring "standard"

[billywhizz]

When I use XLR speaker cable, I have inherited a standard that is pin 1 negative, pin 2 positive, pin 3 not used .

This maybe a standard which has come from the old TP days??? maybe.

 

 

I have heard that other theatres in south-bank use pin 2 pos, pin 3 neg .

 

Is there a recognised standard???

 

If so where did it come from??

 

I am interested in the history more than starting a forum war!!!!

 

Thanks for any help.

 

billy

[Bobbsy]

Well, my take on it is that the use of XLRs for speaker cables is, in itself, not standard (and bad practice to boot) so manufacturers who choose to use this connector pretty much make up their own methods as they go along.

 

 

 

Bob

[Chappie]

so manufacturers who choose to use this connector pretty much make up their own methods as they go along.

So you would include Meyer Sound, one of the worlds most established loudspeaker manufacturers in this assumption would you?

[ChrisD]

You've got to be a bit daft designing speaker connectors which are the same as line level connectors. It's just begging for someone to accidentally plug one channel wrong in the amp rack.

 

A slightly more heinous crime is the usage of line jacks or guitar leads by amateur bands to go between their amps and speakers, it does proper nasty stuff to the sound. Unlike XLR, Jack connectors on speakers are generally found on cheap-o disco kit from maplins et al.

 

Just my £0.02 (ex VAT, inc P n P)

[Simon Lewis]

So you would include Meyer Sound, one of the worlds most established loudspeaker manufacturers in this assumption would you?

 

As far as I know, XLR pin 1 has always been used as the shield connection, but it took about 10 years before the AES finally agreed on a standard for pin 2 to be the "hot" connection. This of course applies to signal level, not loudspeaker level.

 

Many firms used XLR pin 1 -ve, pin 2 +ve for loudspeakers, but larger amplifiers can present dangerous voltages on these exposed pins. Therefore this practice has died out somewhat. Some reversed the XLR's gender on the loudspeaker cabinet (e.g. Bose 802s), but that just led to various adaptors being needed (and lost!). Obviously, it wasn't a good idea to reverse the gender at the amplifier!

 

Some used 4pin XLRs to differentiate from mic circuits. However, that gave rise to about 12 different pin and polarity variations! They didn't catch on.

 

Meyer Sound used EP connectors on their non powered boxes, sometimes with different pin counts between US and European boxes. Their powered boxes use standard XLR connections for signal level input. I've not come across a non powered Meyer box with an XLR on it. That's not to say they don't exist...

 

Other manufacturers have used EPs, PA-Cons, Cannon loudspeaker connectors (two non mateable versions) and many still fit binding posts to their loudspeakers and amplifiers, although there are touch hazards and the possibility of cross connecting with Schuko mains leads.

 

In all of this, it's been hard to impose a standard. The nearest has been the use of the Neutrik Speakon connector (cf AES 45) although even this can be used in many different ways [full range pins1+/-, biamp, bridged across pins 1+ / 2+, used as a low voltage connector for lights on a display stand ;-) ]

 

 

So, I'd agree with Bob - use of XLRs for loudspeakers isn't really a good practice.

 

Simon

[bruce]

I think the current "standard" is "don't do it" :D .

 

I'm not aware of any manufacturer who still uses XLRs for speakers - unless you know better! - it all dates back to the pre-speakon days, where an XLR wasn't ideal, but was much better than a jack...

 

But I can think of various bits of kit that I've owned over the years - Celestion, Bose, Peavey, Carlsbro, and various others - that have used this convention.

[Rob_Beech]

Jack connectors on speakers are generally found on cheap-o disco kit from maplins et al.

 

 

yamaha S215IV and SW215IV both used jack connectors. Whilst they are not top of the range gear by any means they are certainly not cheapo disco kit.

 

but I fully understand where you're coming from.

 

my opinion is alter the connectors on the box if this is possible to NL4's makes things so much easier.

 

 

rob

[paulears]

I think that including Meyer and Turbosound and others in the list of people who make up their own rules is quite accurate. I mean, they chose a connector that is mechanically reliable, has reasonable current carry capacity and works. Compatability with other manufacturers gear was pretty low on their list at the time. Now it is pretty silly to use a common low level connector in this way, but they are Meyer and Turbosound, and they can do what they want. Things like EPs are much bigger and when they wanted more than 3 circuits, that made sense.

 

None of this 'makes' a standard. The same applies to jacks. Horrible choice for a speaker connector, but plenty use it. Nowadays it is pretty much the disco end of the market - as in low budget, low quality, but hasn't always been. Yamaha, Bose and plenty of others found it acceptable before Mr Neutrik came along with his speakon.

 

So - standard it isn't, and never really has been, but it works, and works on some of the wrold classiest systems, of a certain vintage. Does it really matter that much? Everybody worries about plugging an amp feed meant for a speaker into a mic - but I can't say I've ever heard a first hand story of this. If you know your system uses a common connector, you just take a bit more care.

[MarkPAman]

Everybody worries about plugging an amp feed meant for a speaker into a mic - but I can't say I've ever heard a first hand story of this.

 

Same here, but...

I was once called to see why a system didn't work, and found there was no amp between the desk & the speaker!

[Simon Lewis]

Everybody worries about plugging an amp feed meant for a speaker into a mic - but I can't say I've ever heard a first hand story of this.

 

I've had several church installations where the speaker XLR to a platform wedge has been plugged into the stagebox. The users say that they cannot understand why a particular channel is dead, but after replacing the desk's blown input chip we cottoned on to what was wrong.

[CPlater1]

I know of some unpowered speakers using XLRs, but these are quite old. at our school the main speakers we used were Coomber, which ran from XLR inputs

 

Chris

[Bobbsy]

so manufacturers who choose to use this connector pretty much make up their own methods as they go along.

So you would include Meyer Sound, one of the worlds most established loudspeaker manufacturers in this assumption would you?

 

Let's be clear...I'm talking about the feed from a power amp to a passive speaker here. An powered/active speaker takes a standard line level input and an XLR is fine for that. It's putting an amplifier output onto a connector that normally carries mic/line level that I take serious issue with.

 

Bob

[phil dekked]

Everybody worries about plugging an amp feed meant for a speaker into a mic - but I can't say I've ever heard a first hand story of this.

 

I've had several church installations where the speaker XLR to a platform wedge has been plugged into the stagebox. The users say that they cannot understand why a particular channel is dead, but after replacing the desk's blown input chip we cottoned on to what was wrong.

 

I have on my desk the input card to an amp .....nice and crispy! Someone took the XLR output of one amp and plugged it into the input of another! He thought that was how you daisy-chain signals................

I`ve seen mic cables running 500 watt monitors as spkr cables......nice and warm to the touch!

 

We used to run XLRs years ago but have moved onto NL2 / nl4 / nl8 throughout the system. No confusion with whats a signal and whats a spkr cable anymore ( we had different colours for both back in the day) . The speakon range is well thought out and highly adaptable , why anyone still wants to use XLR is a bit worrying ...how much cost are they trying to cut!

The EP range is pretty good but the male ends tend to get squashed a bit easily and results in ham-fisted crew trying to force them into boxes..! Also some manufactures use 5 pin , some 6 pin for a three way active box...?

Pa con is nice and robust but a bit pricey.

 

XLR is for signal and it should stay that way

 

.p.

[Pete Alcock]

When I was at BBC Brainwashing House in the early 80's XLR's were commonplace for speaker connections, particularly into the back of the speaker box.

 

Little studio monitors like LS3/5As that were driven off 30W H&H amps used a male XLR that was wired (IIRC) Pin 2 +, Pin 3-. The worst you could do was plug a mic into the end of the speaker cable! The bigger, active monitors driven from Quad 303's and 405's used 4 pin XLRs.

 

Given that the Beeb set many standards in years gone by, and that reliable connectors with some current-carrying capacity were scarce (EP connectors were used for mains cue lights in studios!), this could be why XLRs were frequently used.

 

I used XLRs on all my kit until a few years ago, and wired pin 2 + and 1&3 -. It did have the advantage on big distributed systems that you could daisy chain loads of speaker cables together without the need for those little speakon barrel thingies. (And if you did run out of speaker cable you could always use a mic cable at a push.)

 

Pete.

[bruce]

.... you could daisy chain loads of speaker cables together without the need for those little speakon barrel thingies.

 

 

Which reminds me - I noticed that CPC are now doing Speakon-style 4 pole line sockets, which always seems to have been the part missing from the range. Part number AV08551, DAP audio. Solder connections. At first glance, when assembled, it could easily be mistaken for a Neutrik.

 

I've got a few of them, connected to short lengths of 2.5mm cable with bare "tails", that I leave permanently connected to power amps which only have binding post outputs...