Need 1/4" jacks that are sealed from airflow, mount in steel plate electrically insul
My commercial-styled speakers each have 2 steel plates in the back. One of the plates in each box is for jacks and comes pre-drilled for 2@ Neutrik Speak-on and 2@ 1/4 inch TS phone Jacks. These are sealed cabinets, and I can't have jacks that allow air to whistle in and out when there is no plug insterted; they need to be sealed. They also need to be electrically insulated from the steel plate they mount on, so that the two 1/4" sleeves of the jacks are not connected to each other (the two jacks have different functions).
Are these sealed against air flow when there is not a plug insterted?
Jack Socket, Mono
Or these:
Neutrik NMJ4HC-S 1/4" Mono Phone Jack Switched 090-972
or should I file out the big holes and drill the little holes to take these:
Neutrik NJ3FP6C-BAG 1/4" Locking Chassis Jack Black 092-084
(also available in nickel) Just how hard is it to cut the typical steel plates (mine are from Reliable Hardware) without a chassis punch (which might still have some trouble with steel).
I already have a lot of these, but they're for low-power and obviously not electrically insulated from the mounting plate, more appropriate in the edge of a guitar:
Rean NYS2202 1/4" Mono Jack Thick Panel 092-126
My commercial-styled speakers each have 2 steel plates in the back. One of the plates in each box is for jacks and comes pre-drilled for 2@ Neutrik Speak-on and 2@ 1/4 inch TS phone Jacks. These are sealed cabinets, and I can't have jacks that allow air to whistle in and out when there is no plug insterted; they need to be sealed. They also need to be electrically insulated from the steel plate they mount on, so that the two 1/4" sleeves of the jacks are not connected to each other (the two jacks have different functions).
Are these sealed against air flow when there is not a plug insterted?
Jack Socket, Mono
Or these:
Neutrik NMJ4HC-S 1/4" Mono Phone Jack Switched 090-972
or should I file out the big holes and drill the little holes to take these:
Neutrik NJ3FP6C-BAG 1/4" Locking Chassis Jack Black 092-084
(also available in nickel) Just how hard is it to cut the typical steel plates (mine are from Reliable Hardware) without a chassis punch (which might still have some trouble with steel).
I already have a lot of these, but they're for low-power and obviously not electrically insulated from the mounting plate, more appropriate in the edge of a guitar:
Rean NYS2202 1/4" Mono Jack Thick Panel 092-126
No, I don't just put in plugs. Small-volume isobaric can even spit out the active plug, another reason I want sealed. Anybody know whether the ones I linked to are sealed? Teh oens from Reliable Hardware they claim (on phone) that they ARE sealed but they don't look it in the pictures.
Jack Socket, Mono
Yes, I've made small boxes behind before, but these isobaric cabinets are so small I don't want to take away more interior room. I've considered small aluminum chassis inside, but then I need to seal where the heavy-guage wires pass thru that box to the speakers also.
If the locking Neutrik is sealed, customer replies say I a binding screw can isolate the 1/4' sleeve from the chassis, which sounds perfect. Except for cutting all those darn holes in steel! i wish I had aluminum recessed plates instead of steel.
Jack Socket, Mono
Yes, I've made small boxes behind before, but these isobaric cabinets are so small I don't want to take away more interior room. I've considered small aluminum chassis inside, but then I need to seal where the heavy-guage wires pass thru that box to the speakers also.
If the locking Neutrik is sealed, customer replies say I a binding screw can isolate the 1/4' sleeve from the chassis, which sounds perfect. Except for cutting all those darn holes in steel! i wish I had aluminum recessed plates instead of steel.
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A locking Neutrik will do what you want. Better is of course the actual Neutrik speaker connector. You can buy cups already with the standard Neutrik cut out.
If the pressure is high enough to force out a 1/4" plug then we should talk about case design and the pressure distribution inside it. You probably don't want a metal plate at the point where the pressure is that high. A small pressure sensor is not very expensive and will teach you a lot about where things really happen. The other useful tool is an accelerometer.
If the pressure is high enough to force out a 1/4" plug then we should talk about case design and the pressure distribution inside it. You probably don't want a metal plate at the point where the pressure is that high. A small pressure sensor is not very expensive and will teach you a lot about where things really happen. The other useful tool is an accelerometer.
It's my first large-ish isobaric project. When they spit out plugs the jacks admittedly have insufficient tension. I have 4 drivers in each box, two isobaric clamshelled pairs. Plate comes pre-punched for 2 neutrik (which I have mounted) and 2 1/4" jacks. I also mounted another blank plate in each cabinet. The peak pulses are double the pressure because it's isobaric, but the pressure peaks are also high because I brace the cabinets pretty thoroughly against expansion or contraction.
The more I think about it the more I'm inclined to just put a 5/8 bolt and locking nut in the holes for the 1/4" jacks. But those Neutrik locking 1/4" jacks look great if I had the right chassis punch. I wonder whether Harbor Freight has a cheap one that would do the job.
The more I think about it the more I'm inclined to just put a 5/8 bolt and locking nut in the holes for the 1/4" jacks. But those Neutrik locking 1/4" jacks look great if I had the right chassis punch. I wonder whether Harbor Freight has a cheap one that would do the job.
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Here's a more interesting question:
If I have a bunch of nearly-identical drivers (same t/s parms) but some have ventilated pole piece and others don't, should I try to use the vented ones as the inside driver or outside driver of the isobaric pair? The inside one will have more long-term cooling problems. The vented polepiece may also help the dustcap area take "isobaric load" just like the cone area, but I'm not completely sure that's good. I imagine for the vented polepiece to have value it needs some volume of air behind it, so it might be much more effective for the outer driver. Then again, in an isobaric with a small box volume the outer driver always has slightly more excursion than the inner driver.
If I have a bunch of nearly-identical drivers (same t/s parms) but some have ventilated pole piece and others don't, should I try to use the vented ones as the inside driver or outside driver of the isobaric pair? The inside one will have more long-term cooling problems. The vented polepiece may also help the dustcap area take "isobaric load" just like the cone area, but I'm not completely sure that's good. I imagine for the vented polepiece to have value it needs some volume of air behind it, so it might be much more effective for the outer driver. Then again, in an isobaric with a small box volume the outer driver always has slightly more excursion than the inner driver.
Another option if you are not married to the combo dishes is to use the Neutrik Speakon to 1/4 adapter if you need both. Then all connectors on the dish are sealed.
XLR connectors are only supposed to be used for low-level signals, not high-current speakers, though Bose did try to use them as optional on some of their PA speakers. XLRs are for low-impedance balanced inputs or line-level. And you can't connect heavy-guage high-current wire to XLR plugs either. They're just not appropriate for the job.
That's actually a good option, I just wish the plates hadn't come pre-drilled for the 1/4" jacks.
The more I think about it the more I like it.
Or try just gobbing pure silicone on the back of the 1/4" jacks since its non conductive when its dry. I've done that before.
Back in olden times when XLR connectors were Cannon connectors, they had a rather high current rating. Like maybe 15 Amps.
If the amp is not inside the box, why do you need to bring line level into it?
Or are you planning on using line level connectors for power?
So I looked it up. Back in 1978, 3 pin ITT-Cannon XLR connectors were rated at 15 Amps per contact and #14 wire. 4 pin connectors at 10 Amps. 5 pin connectors at 7.5 Amps.
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