Non-Standard Connectors

One of the beauties of DIY is the fact that we're not stuck with standards adopted by the industry-at-large. No better example of this are the connectors used to tie our various components together; RCA and XLR connectors for line level connections and the multi-way binding post for speaker connections.

While each of these (though much less so the XLR) have been much refined over the years by specialty manufacturers seeking better performance over the bog standard commercial offerings, they're still locked into the basic standard in order to maintain compatability.

Yet in spite of not being ball-and-chained to standard connectors, most all DIY projects end up using them in one flavor or another.

About 13 years ago while having lunch with the area Lemo rep (a real character of a Scotsman named Andrew Baxter--which I only mention because I'm surprised I still remember his name) regarding some Lemo connectors I was interested in for a commercial project, he reached into his sample case and tossed me this little thing, suggesting I give it a try:

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<img src="http://www.q-audio.com/images/redel.jpg">
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Basically, a medical grade (autoclavable) plastic version of the Lemo B series metal shell connectors made by <a href="http://www.redel.com">Redel</a>.

I thanked him, but didn't have any plans to use it on a commercial product at a time when everyone wanted things made out of precision machined metal.

However sometime later when I was making some major changes in my personal system, I plucked the Redel out of my sample box and gave it serious consideration.

It had a number of attributes that appealed to me in spite of it being made of plastic. It was small, not much larger than the beefier RCA connectors. It was a locking connector that was exceedingly simple to use. Just push it in until you hear it lock in with a click and while no pulling on the cable will disconnect it, all you have to do is pull on the body and it disconnects with a breeze.

The nested cylindrical construction of the plug/recepticle provided a gas tight environment for the connectors proper. And the connectors are small, simple pin/socket arrangements which result in what amounts to a simple inline splice for the wire as oposed to tacking the wires to large chunks of metal.

The plugs are available with either crimp or solder connections. The recepticles are available with crimp, solder as well as straight and right-angle PC mount versions. They're also a keyed connector available with four different keying (I use three different ones, one for line level, one for speaker level and one for DC power).

To make a long story short, I've compared them to a fair variety of RCAs, XLRs and even proper Lemos and for me, the Redels have always come out the winner. In fact, I even use them for my loudspeaker connections.

I use a quad geometry cable for both my line and speaker connections and use the 4-pin version of the plug (the photo's the 7-pin version I was first given as a sample). It lets me maintain the quad geometry all the way through the chassis.

The closest I found to the Redels were some plastic shell Neutrik XLRs. But I find XLRs to be rather laughably large for what they have to do.

Anyway, if you're feeling rebellious and would like to try something different, take a look at the Redels.

se
 
Steve and all,

seconded, the Redel :yes: is the absolute undisputed heavyweight champion as far as audio connectors are concerned.

I tried them out, i was stunned, i spread the word and now Allen Wright is using it too.

I made listening comparisons with a connector patched into the MC phono lead. Several swiches and connected, Lemo 3B and Redel among them.

Well, as far as insulator and connector pin material and metaliations is concerned, Lemo and Redel are the same, so states the manufacturer. And both have the same almost non-existent sonic deterioation (comparison: connector in the circuit either bridged by a solder joint or only, unbridged.). No switch, not RCA plug came even close.

Steve,
i even agree with the Redel bettering the Lemo as a complete plug. The Lemo has a beautiful massive metal body which atleast is a shielding, but probably has some slightly magnetic parts. I always found it prefereable sonically when i removed a shield not fewrvently needed. Today, not even my MC phone cable has any shielding, it just is a twisted pair of enamelled copper wire.

There is another point: 1 plug and 1 jack Redel should cost together about US$12. A Lemo 3B plug and jack costs more than $120. For the differnece i buy vintage vinyl. :)

One thing, one should agree on a pin count if another group purchase comes to mind. I prefer 6 ins as i can then solder ribbon cables to a pin pair: just the right thing for balanced cables with center shield if needed.
 
dice45 said:
i even agree with the Redel bettering the Lemo as a complete plug. The Lemo has a beautiful massive metal body which atleast is a shielding, but probably has some slightly magnetic parts. I always found it prefereable sonically when i removed a shield not fewrvently needed. Today, not even my MC phone cable has any shielding, it just is a twisted pair of enamelled copper wire.

I never found any magnetic parts in the Lemos. Here's perhaps another way of looking at it:

Many people are concerned with the dielectric properties of the materials used in cables, up to and including the jacket, attempting to achieve the lowest dielectric constant possible. While plastics such as PVC may be the worst in this regard with respect to plastics, consider the dielectric constant of aluminum. :)

I don't use shielding either. I'm currently getting along with nude Canare microphone cable which has had both the jacket and shielding stripped off. I don't have any RF problems and the best way to shield cables from magnetic field interference is to keep a close spacing between conductors.

Of course some systems are problematic with regard to RF so shielding isn't much of an option for some.

se
 
Re: Lemo

Elso Kwak said:
Hi Steve Eddy,
I am using all Lemo connector system on my preamp. I love it. I sticked to the Levinson system. Interestingly Mark Levinson abandoned the Lemo or Camac system later.

Yes. Don't know that he had much choice. They never caught on commercially like I'm sure he was hoping they would and customers were getting tired of messing around with adaptors.

In the commercial world, I just don't see anything overcoming the momentum of RCAs and XLRs.

se
 
MRehorst said:
How is the ground connection made, and is it made before the other contacts?

All the pins in a given connector are the same so all pins make contact pretty much at the same time. So they're not quite like an RCA where you can have the center pin making contact well before the barrel makes contact.

I've only used them in my own gear which is transformer coupled so it's not an issue for me. Perhaps some of the others can relate their experience with making connections with the equipment turned on.

se
 
Ground Connection

MRehorst said:
How is the ground connection made, and is it made before the other contacts?

MR
Hi,
The gound connection is made before the live connection.
You can plug and unplug without a large bang as with the RCA's.
Ground is the case of the connector.
Also a pull on the cable does not disengage the plug; you have to hold the plug to unplug it.:happy1:
 
Re: Ground Connection

Elso Kwak said:
The gound connection is made before the live connection.
You can plug and unplug without a large bang as with the RCA's.
Ground is the case of the connector.

That would be the case with the Lemos (well, if you choose to tie ground to the body rather than using the pin/socket connectors), but not the Redels, which have a plstic body.

se
 
Re: Lemo's

Elso Kwak said:
Yes Steve Eddy that is the case I only use Lemo's or Camacs and the ground is connected to the case as did the Mark Levinson company. The shield is clamped, not soldered, in a convex cup. The Redels are new to me. ;)

Oh, ok, you're using the coaxial connectors. I've only used the circular, multi-pin Lemos.

I see where you're coming from now.

se
 

pinkmouse

diyAudio Moderator Emeritus
2002-04-03 7:15 pm
Rotherham, England
Ok how about these- solid copper, 600A rated,and they can only be pugged in in the correct order... ;) :) Great for Slice's and Kilowatt's huge amp projects! :) :) :)
 

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That IS the best about DIY you don´t need to go along with the industry standards.

Like for instance RCA or cinch plugs used for digital inputs and outpuin CD players or DACS or for video in AV systems. You can really throw up on them.

Connecting Ground before live is a very cool idea.
Like the Neutrik audio plugs.