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Convert 1/4 jack to Speakon on my head?

creis2

creis2

Guest
Nov 11, 2011
703
1
Cambridge, MA
#1
I know it's not necessary, but I enjoy these kind of modifications.

I have an old Ashdown head with 1/4 jacks.

575 watts RMS 1000 watts peak.

One of the 1/4 jacks needs to be replaced, I figured might as well do this since most of my cabs have only speakon connectors and the 1/4" to speakon seems a bit weird.

I was thinking about drilling into the back and switching the 1/4" out for speakons.

The 1/4" jack is soldered right into the pcb. I was thinking about desoldering it, resoldering wires into the holes of the pcb and run those right into the freshly drilled speakon connectors.

Is this a dumb idea?

Not at all concerned about resell value.
 
#4
In principle yes. In practice, maybe not so easy to pull off.

Drilling a hole in the chassis might not be so easy. It depends on how much space you have inside the chassis where the 1/4" jack is. Unless you have a special cutter, drilling and smoothing the hole can get messy.

I find that the easiest way to cut a hole for a speakon is with a punch. I use a Greenlee 15/16" punch for D-size speakons like the ML4MP. You have to have the room inside the chassis to do this though. One piece of the punch goes on the inside of the chassis, one goes on the outside. There is a threaded stud. You use a wrench to draw the cutter through the metal. A few turns and you have a perfect hole.
 
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#5
Hi.

A lot of work for little or no gain if You ask me.

That said I did convert the US AC aux socket on my SWR ST220 to a Speakon, but no filing/cutting IIRC. The connector sits a bit crooked, but it doesn't bother me.

beans-on-toast said:
I find that the easiest way to cut a hole for a speakon is with a punch. I use a Greenlee 15/16" punch for D-size speakons like the ML4MP. You have to have the room inside the chassis to do this though. One piece of the punch goes on the inside of the chassis, one goes on the outside. There is a threaded stud. You use a wrench to draw the cutter through the metal. A few turns and you have a perfect hole.
Click to expand...

^This.

Otherwise You have to strip the chassis bare, ONE chip in a wrong place and You may kiss your amp goodbye. Or at least a trip to a tech will be necessary.

Regards
Sam
 
#7
I too like to mod gear to my personal taste. Your idea is a worthy mod BUT, if the amp has a pc board mounted 1/4" jack there may not be enough room to install a Speakon connector. I have a spare laying around and would try and see if there was enough room to mount it before cutting anything. +100 on the Greenlee knockout punch for making holes in steel chassis, that is how to do it cleanly. You may have to cut up the pc board to provide clearance for the new connector and at some point I might balk at that and either install it somewhere else or drop the idea if there just isn't enough room. Enjoy modding it's fun just give it some thought first.
 
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#8
Do you want Speakon specifically? Or are you after the overarching goal of using a connector scheme that's suitable for speaker loads? If it's the latter, then consider banana jacks, which have been used for years for very high current speaker loads. Installation is a breeze. Space them for a dual plug that has the built in loop/strain relief for the cable. If the loop isn't wide enough for the cable jacket, you can strip away the jacket and put shrink wrap over the (insulated) conductors, or you can make your own strain relief with a nylon cable tie.
 
#9
Well, I have a few heads and cabinets and all of them have speakons except this one. I just like the idea of having one type of speaker jack for all of my heads.

I'm looking to gain a modern setup.

There is space to install the speakons a few inches away from the current jacks. I would run a wire from the PC board to the speakons.

I would yank the guts out of the chassis before I did this.

Unless someone can tell me it wouldn't be worth the $100 or so investment buying the bit, speakon connectors, parts, etc.

From what I read on here, speakons can be a huge improvement, am I wrong?
 
#10
I don't know about a "huge" improvement, however speakons are safer for high current loads and it would be more convenient for you.


BTW, how is it that you want to do an extensive mod on your head like this and don't make your own cable?
 
#11
Andyman001 said:
I don't know about a "huge" improvement, however speakons are safer for high current loads and it would be more convenient for you.


BTW, how is it that you want to do an extensive mod on your head like this and don't make your own cable?
Click to expand...

Making my own cable is simple, but my concern is having the optimal setup.

If I can keep my current 1/4" setup and still have a safe setup that allows me to have high current loads, that would be best.
 
#14
I would absolutely do it if you have room for the jack. Get one of the stepped drill bits that are designed for sheet metal to enlarge the hole - they do a great job if you go very slow and will leave a smooth edge. Cheap at Harbor Freight, etc.

1/4" jacks for speaker current is one of my pet peeves.
The contact area of the tip is so small, it's a wonder they work at all.
 
#16
A Speakon has other advantages to a 1/4" jack, other than current. One can short out an amp with a partially plugged in 1/4" plug but shorts with a speakon are not possible, (other than a short inside the plug itself). XLR's have been used for the same reason.

I do have a collection of stepped bits. My largest two are still a bit too small for a speakon hole. I have replaced a few jacks with Speakons, and if I only have room for one jack, I use a Speakon type that also has a 1/4" jack in the middle.
 
#17
creis2 said:
I'm interested in doing it because:

-Buying speakon to speakon cables are easier than buying speakon to 1/4"

-Want the absolute best protection possible.

-Want to make sure I'm getting every once out of my head I can.
Click to expand...

- Yes, speakon to speakon cables are easier to find.

- Yes, speakons lock into place and wont jiggle out with vibration

- Speakons wont squeeze any more watts from the amp, but in applications where you're running 300+ watts into a cab(s), the speakons provide solid, reliable connections.

IMO, this is the most sensible/practical mod that can be made to your amp.

Ive retrofitted all my amps with speakon outs (except a vintage 50w bassman...wanted to leave it factory for resale reasons).
 
#18
I think I'm going to do it.

I'm going to avoid the harbor freight step bit and buy a quality one at my local wood supply shop.

Had a Harbor Freight bit explode in my face once and had chunks of metal inside my eye socket. They removed them with magnets and tweezers.

My father in law is an eye surgeon, said I'm lucky that I'm not blind.

Safety Goggles people! :crying:
 
#19
Could I desolder the 1/4" jacks from the board and use the available holes on the PCB to solder a short wire from the board to the new speakon connectors?


Also, on the speakon connectors have 4 prongs.


+1 is positive and -1 is negative right?

+2 and -2 should be left alone for my application?
 
#20
creis2 said:
Could I desolder the 1/4" jacks from the board and use the available holes on the PCB to solder a short wire from the board to the new speakon connectors?


Also, on the speakon connectors have 4 prongs.


+1 is positive and -1 is negative right?

+2 and -2 should be left alone for my application?
Click to expand...

Yes. Yes,. and Yes.

Try to use 16 ga (or larger) stranded wire from the pcb to the new speakon connector
 

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