• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). There are daily reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Compact balanced connectors

kchap

Senior Member
Forum Donor
Joined
Jun 10, 2021
Messages
377
Likes
375
Location
Melbourne, Oz
Since the definitive connector for multichannel balanced connections has yet to establish itself (even DisplayPort has been used before), you pretty much have to go with what makes most sense to you. Even 12x 1/4" TRS would be a fair bit more compact. If it's not too fiddly and you can get ready-made audio cables (studio retailers seem to be stocking several options, e.g. prices at Thomann ranging from about [email protected] to 120€ a pop), DB-25 wouldn't be such a bad bet.
The 6.35 mm TRS was used (still used?) in broadcasting for years. It's pretty reliable.
 

GeorgeBynum

Member
Joined
Feb 14, 2020
Messages
98
Likes
82
Location
Greenville SC USA
That being said, as far as I understand, my options are

4) ...

110Ohm DMX cables with 5pin XLRS seem to be readily available, and I was wondering if these can be used for audio.
Not designed for audio, but industrial 8mm (3 & 4 pin) and 12mm (4, 5, & 8 pin) screw connect are very available. I use them with transducers. In the USA, try AutomationDirect.com for their reasonably priced range. This picture is the 8mm 3 pin.

1630515999287.png
 

restorer-john

Master Contributor
Joined
Mar 1, 2018
Messages
9,183
Likes
25,955
Location
Gold Coast, Queensland, Australia
Ugh. Flimsy and with unreliable physical coupling.

The old DIN series of round 2-8 pin horrors should never have seen the light of day. My least favourite was the evil 2 pin used in the early 70s on euro speaker terminals.

And the Scart. Whoever designed that should have been locked up.
 

tomchr

Addicted to Fun and Learning
Manufacturer
Forum Donor
Joined
Nov 5, 2018
Messages
946
Likes
2,510
Location
Calgary, Canada
The Mini-DIN that followed wasn't any better.

The terminals on the back of the MiniDSP 4x10HD shown in the first post are commonly called Euro connectors or generically, pluggable terminal blocks. They have 3.81 mm pin pitch. I'm not a huge fan of them on the outside of equipment, but they are compact.

Tom
 

tomchr

Addicted to Fun and Learning
Manufacturer
Forum Donor
Joined
Nov 5, 2018
Messages
946
Likes
2,510
Location
Calgary, Canada
3-pin TRS is very compact and is an industry standard. Focusrite Scarlett 18i20 shown below.

MOSC0015UKEU_5.png


Only annoyance is that if you go from TRS to XLR you'll need two cable sets. One with male XLR and another with female XLR.

Tom
 
OP
A

ai1

Member
Joined
Jul 1, 2020
Messages
47
Likes
13
Ugh. Flimsy and with unreliable physical coupling.
I have horrid memories of russian-built (soviet era) din plugs. It sounds, they were not much better on the other side of the wall;-)
 

Neddy

Addicted to Fun and Learning
Forum Donor
Joined
Mar 22, 2019
Messages
559
Likes
682
Location
Wisconsin
You might want to look into Lemo connectors.
https://www.lemo.com/en
Not audio particularly, but I worked in a physics lab where they were used For Everything (think CERN, only 70s, in US), mostly 50 and 75 ohm data lines, and have them on all my oscilloscope probes as a result:eek:
Very durable, simple to use (just Pull (sleeve) to remove), tiny footprints.
Ever since using these, XLR, DIN, Amphenol (ugh), TRS, etc just look silly and too steam punk for me!
Pick your style and pinout config.
Pricey, though.
 

Skeptischism

Active Member
Joined
Sep 6, 2019
Messages
229
Likes
119
yeah I was going to suggest lemo, or amphenol, great stuff, but pricey. love them, but for 12 balanced channels youd end up spending over $500.

i'd vote for DB25. actually not that difficult to solder. since its balanced audio, is there any reason you actually need a ground wire for each channel? I would expect that would not even be desirable. 25 pins is 12 x 2, plus 1 shield/gnd. or do you need to have it XLR at the other end like a breakout cable? if its DB25 -> db25, I dont see why 25 pins wont work. ground doesnt carry any return signal in balanced audio
 

Adam Bernau

Member
Forum Donor
Joined
Apr 14, 2020
Messages
83
Likes
137
Two years ago I have built a 12ch amplifier using 3e audio modules. It is working flowlessly ever since.
However, 12 xlr connectors produced quite a bit of clutter and ate significant space of backplate (I use the HIFI2000 2U enclosure from audiophonics.fr).
View attachment 150712
I am looking for alternatives to save some space to eventually add a fan, but I would like to keep balanced connection between MiniDSP 4x10 and the amplifier (I have not tried unbalanced yet, and because balanced is here, utilizing it seems reasonable). That being said, as far as I understand, my options are
1) 5 pin stereo XLR connectors
2) 3 or 5 pin miniXLRs connectors
3) 3 pin TRS
4) ...
5pin XLR looks as an interesting option: not only using it would allow to divide by 2 the surface used by connectors, but the wiring will also become simpler in this case.
However, it looks like they are not really commonplace in audio, and I am wondering how "standard" 5pin balanced (stereo) connectors are.
I have found 2 schemas of the wiring of this connector
View attachment 150713View attachment 150714
which seem contradictory (unless I do not understand what is "hot" and what is "cold").
That being said, 110Ohm DMX cables with 5pin XLRS seem to be readily available, and I was wondering if these can be used for audio. I am thinking to give it a try--my cables are only 30-50cm long, but I would be surely happy to get an educated opinion.

My favourite solutions for these situations are those very cute and reliable Mini XLR connectors
https://www.amphenol.com/node/4901
 
OP
A

ai1

Member
Joined
Jul 1, 2020
Messages
47
Likes
13
yeah I was going to suggest lemo, or amphenol, great stuff, but pricey. love them, but for 12 balanced channels youd end up spending over $500.

i'd vote for DB25. actually not that difficult to solder. since its balanced audio, is there any reason you actually need a ground wire for each channel? I would expect that would not even be desirable. 25 pins is 12 x 2, plus 1 shield/gnd. or do you need to have it XLR at the other end like a breakout cable? if its DB25 -> db25, I dont see why 25 pins wont work. ground doesnt carry any return signal in balanced audio

Thanks. Indeed, I am wondering if I need multiple ground wires on the MiniDSP side. Would it be OK if I just connect the (25-th) ground wire with the amplifier box?
 

MenloBob

Member
Joined
Jul 10, 2019
Messages
58
Likes
60
Have a search for audio snake ethernet. Each cable can carry 4 pairs of balanced signals. If you are building everything on your own it makes most sense.

I want to second this idea. Neutrik makes some very nice Ethercon D sized panel mounts that would fit nicely in place of 3 of your current XLR connections. Get a length of flexible, shielded, stage grade cat5 and make 3 cables to connect directly to the phoenix connectors on the back of the MiniDSP. A few blank D connector covers and done.
 

Kal Rubinson

Major Contributor
Industry Insider
Joined
Mar 23, 2016
Messages
4,232
Likes
6,938
Location
NYC/CT

Skeptischism

Active Member
Joined
Sep 6, 2019
Messages
229
Likes
119
Someone used them in their audio electronics a ways back but I cannot recall who.


Me, too.
You are probably thinking of Mark Levinson. the switchcraft mini XLR are a better class of mini xlr, if one must be used, but they arent a Lemo. The swiss watch of hi end scientific/industrial connectors. Again, not recommending it here. While they do have stuff in their catalogue that would take care of you nicely. they would cost you an arm and a leg. The N series, for nuclear applications ... so sexy ... :p I shudder to think of the cost.

One thing, there are definitely DB25 connectors and DB25 connectors.
 

Skeptischism

Active Member
Joined
Sep 6, 2019
Messages
229
Likes
119
Thanks. Indeed, I am wondering if I need multiple ground wires on the MiniDSP side. Would it be OK if I just connect the (25-th) ground wire with the amplifier box?
I would think it would be fine. have you got a means of testing it with one channel? if there is a shield in your cable, tie that to the chassis—and chassis only—at BOTH ends (and the db25 shell casings if they are metal) not just one end, both. that isn't signal ground and you shouldnt tie signal ground and chassis ground together at this point (if at all). its not possible to give a clear cut answer, but if you are able to control the way this goes, because you are DIYing: I would expect its possible to connect just one GND pin at minidsp end (all channel grounds will be connected I expect) to signal GND at the other end, or Chassis GND at the amp end only would work too.
 
  • Like
Reactions: ai1
Top Bottom