Connectors for modular tube preamps/line amps, etc.

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NewYorkDave

Well-known member
Joined
Jun 4, 2004
Messages
4,378
Location
New York (Hudson Valley)
I've thought about Jones plugs, 11-pin octals, even DB15s. Any other suggestions? Desirable traits include availability, low cost, ease of making the chassis cutout, suitable voltage and current rating, etc. Ten or more conductors are preferable.

I was really leaning toward Jones plugs, but they appear to be a vanishing breed--or at least it seems the versions with more than a handful of contacts are getting hard to source. 11-pin octals are attractive because of the round cutout--easy to make with a chassis punch--but the availability isn't much better than Jones.

I'm not up on the latest 'n greatest in connectors, so I thought I'd pose the question to the Lab. Perhaps one of you knows of a connector that I haven't even considered.
 
I use octal plugs, available at Allied. I think they have 11 pin also.

You need the B+ clearance for tube stuff.

Usually for me,

1) Gnd
2) 6 volt DC heater supply
3) 48 Phantom
4) B+

No problems using one gnd.

Yet.
 
At minimum, I need:

In +
In -
Out +
Out -
B+
B-
Heater
Heater
Chassis Gnd.

... so, at least nine contacts. It would be cool (although not absolutely necessary) to have additional contacts for P48, gain-set, tube metering, guarding (shielding) pins, or whatever.

Thanks for the tip about Allied; they do have the 11-pin octals. Triode Electronics has them, too, for a little cheaper. This is looking like an OK option--although liable to be discontinued at any time, so I'd love to hear more suggestions!
 
Yeah, I like Jones but it seems the selection of chassis-mount plugs and sockets, available online, is pretty iffy once you get above 6 pins. I want to standardize on a connector for my tube projects and I don't want to choose something that's here today, hard to find tomorrow.
 
the jones stuff looks slick. how would you recommend cutting / mounting it to a chassis? i've always used stuff thats round so i can just drill it or punch the chassis. I'd like to try the jones connectors one day, but i feel like i would make a total mess of it mounting it on a box...
 
Well the shitty way to do it would be dremal but that never works out to stright lines. BUt there are other ways. Like drill out the corners and stick a band saw tfor cutting metal threw and make a straight line. the repeat to do a box,rectangle etc,etc. I myself am looking into a plasma cutter for doing all of that and then some. going to be sick
 
I'm not sure I would bother. Jones seems to be a dying species. There are big gaps in the inventory at most suppliers I've checked. Jones was really popular at one time but I don't remember the last piece of new equipment I saw that used one.
 
[quote author="NewYorkDave"]At minimum, I need:

In +
In -
Out +
Out -
B+
B-
Heater
Heater
Chassis Gnd.

... so, at least nine contacts. It would be cool (although not absolutely necessary) to have additional contacts for P48, gain-set, tube metering, guarding (shielding) pins, or whatever. [/quote]
A lame and obvious suggestion: why not separate supply & signals on two links ? Would broaden the options, but I guess you've already considered & skipped this...
 
I am facing a similar dilemma for gear that will have external PSU. I am hoping that octal plugs/sockets will be around for some time due to their popularity with HiFi folks, and the enormous installed base of octal components market for industrial applications (relays, etc.). The octal can take care of all the power needs of different components. For sheet metal work there are low cost die/punch kits available specifically to seat octal sockets. Audio will remain in standard XLR connectors, probably for the better.
 
I use BBC low level DC 4+1 strand cable and Nuetrik 4 pin XLRs for low level DC

However for the upcoming Valve projects I am having a few problems as well.
Can I use this heavy duty BBC DC cable
http://www.canford.co.uk/commerce/item_33-299_3001255.aspx
Rated at 2.1Kv DC

But is only 2 strand + Shield - can I use the shield as 0v - one of the strands as Heater and the other strand as big valve volts?

As for connectos - I am watching this with interest
 
The more I think about it, and the more I look around at what's available, octal plugs keep looking better and better in terms of price, availability (current and future) and ease of installation. Just don't break that locator pin!

I've sketched a prelimary pinout for an 11-pin octal.

11PinOct.jpg


I arranged the pins which are at AC ground (B+, B- and chassis) to act as "guards" between the pins for the input, heater and output circuits.
 
I'm a little lost as to why you need power and signal in the same cable. The last phantom PS I wired, I added 2 conductors to the cable as a line switch so that if the cable came unplugged, the power supply shut down.
 
You ought to be able wire up just about anything with the 11 pin. Nice to have options. Obviously, you want to stick with whatever pinout you pick for everything, so it does not matter which plug goes where. I did not do this, as different boxes needed different amounts of wiring, had to rewire everything to a standard format so I did not have to worry about blowing something up. Idiot me!

If you could get it down to 8 pins, you can use cheaper and easier to source tube sockets for the power supply, but the plug and can is hard to source in
anyway, so what the heck.




Here is what Allied sent me, without the can:




octal1.jpg
 
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