1. Register NOW and become part of this fantastic knowledge base forum! This message will go away once you have registered.


Discussion in 'Recording' started by vince latulippe, Sep 4, 2011.

  1. vince latulippe

    vince latulippe Active Member

    [TABLE="class: tborder, width: 100%, align: center"]
    [TD="class: alt1, bgcolor: #F5F5FF"]i'm building myself an iso cab. DON'T BACK OUT please. I'm planning on putting XLR Connector and 1/4'' connector (for speaker connection) on my iso cab. As far as soldering the XLR is concerned, i have no problem. The thing is about the 1/4''. i already have a #12AWG speaker cable that i used to conenct my Mesa Single Rectifier Rectoverb to my 4x12. and i took out one of my two speaker that i had in my Marshall MG250 which i know was 8ohm each. The thing is that i have a STEREO 1/4 connector and all those SPEAKER cables are mono. how shoul i solder everything and will it blow my amp ?? The 2 little ''plug'' on the bulk wire are to connect onto my speaker.

    I REALLY NEED HELP, i dont wanna blow me freaking mesa boogie lolll


  2. Kapt.Krunch

    Kapt.Krunch Well-Known Member

    Before you do anything, you'll want to make sure that Neutrik connector is rated to handle high power from a Boogie amp. If it's a TRS jack, it's likely designed for line-level signals. It may be OK, but you definitely HAVE to know. A meltdown in there will endanger your amp.

    If the connector has markings, negative goes to sleeve, and positive to tip. The ring isn't used (it's just shorted to the sleeve with a 1/4" plug, anyway.)

    As far as connection, do it logically. A DMM (or some kind of continuity tester) will help. Think about it. A TRS cable has a tip, a ring, and a sleeve. The sleeve is nearly ALWAYS the negative (or ground) lead. The tip is always positive. It can be one channel of a stereo output, with the ring being the other. Or, used in a balanced circuit, it can be one phase of the signal, with the ring being the 180 degree opposite phase.

    What happens when you plug a TS (mono) cable into a TRS jack? You short the sleeve to the ring connectors of the jack, with the sleeve of the plug. So, the sleeve and ring are the same thing, negative, while the tip always remains the positive.

    So, simply plug in your amp-to-cab cable to the jack all the way, and find continuity from the tip of the cable to a lug of the jack. That'll be the one you'll connect the red wire to, and then to the speaker +. It's the positive.

    Now, pull the cable out of the jack ONE CLICK. Now, the tip of the cable should have continuity with the ring in the connector, so use your meter to find that lug. That's the lug you WON'T solder to. What you'll find then is that if you measure from the sleeve of your cable to the third lug of the connector, that's the negative sleeve that you want to solder your black wire to, and then run that to the speaker.

    Just make sure that connector can handle a raging Boogie, first! If it were me, I'd do it properly by buying the correct plug panel. Or, just buy a small steel/aluminum plate, and drill a hole to mount a simple 1/4" speaker jack to screw onto the cab.

    Out of curiousity, I can see that the jack appears to be a Nuetrik. Does it have any identifying numbers on it, and if so, what are they?

    Good luck.

  3. MadMax

    MadMax Well-Known Member

    A decent 1/4" power connector is a cheaper cost than the TRS connector you have.

    Just go get the right connector. It's safer and we're only talking about a $5.00 part.

    Why risk blowing up a perfectly good amp over such a small amount of pocket change?
  4. bouldersound

    bouldersound Real guitars are for old people. Well-Known Member

    Or just ditch the 1/4" connection and get Speakon. Phone plugs/jacks were not originally meant for power. They short when you insert them, they have small contact areas and the ones built to handle more power usually don't lock (the ones that lock normally don't handle high power).
  5. dvdhawk

    dvdhawk Well-Known Member

    Excellent advice. It gives you the best possible outcome and can be fitted to the same size Neutrik D-Series hole.
  6. vince latulippe

    vince latulippe Active Member

    can you just give me a website/photos so i'll be sure to buy the right thing.

  7. vince latulippe

    vince latulippe Active Member

    So i should be a 1/4 to Speakon cable to go from my amp to my iso cab with a Speakon connector and inside the cab, a speaker wire connected to the other part of the connector and the speakers? or i could use the same litle ''cutted'' cable that i already have?.

    just please explain to me your ideas... i'm not pretty good with ''making cable''

  8. bouldersound

    bouldersound Real guitars are for old people. Well-Known Member

    I think you've got it right. Build a 1/4" to Speakon cable to go from head to isolation box and put a panel mount Speakon socket on the box wired to a 1/4" plug to go into the cabinet. Many Speakon connectors are designed for crimp connection, no soldering needed but the right crimping tool really helps.
  9. vince latulippe

    vince latulippe Active Member

    okok i see, the thing is that, there's is not a cabinet inside but a single speaker that i took off of my Marshall MG250 DFX. It is a Celestion G12-65 MG. so on the other end of the ''wall plate'' i need to have a bulk speaker cable with some little ''latches'' to connect onto the speaker.

    See photo:

    if i buy a speakon to 1/4'' with like #12 AWG, is there a problem if i take this cable to make the ''inside'' connection even if it is not the same gauge of cable?
  10. bouldersound

    bouldersound Real guitars are for old people. Well-Known Member

    That should be fine. The gauge doesn't need to match as long as the thinnest wire in the circuit is sufficient. So just connect the other end of a wire like the one shown to the back of a panel mount Speakon.
  11. vince latulippe

    vince latulippe Active Member

    and finally, will the speakon conenction handle high power from my mesa boogie ??

    and finally. should i buy something like this: Premium Speakon to TS Speaker Cables
    with this: 2 p pole conductor wire panel mount speakon connector | eBay

    is 2 pole enough and what does it mean??
  12. dvdhawk

    dvdhawk Well-Known Member

    I'm not sure what you mean by "there's is not a cabinet inside but a single speaker", but you've got to get the wire through the outer iso-box. It would stand to reason you would mount the Panel Mount connector where it's accessible from the outside.

    The Speakon can handle thousands of watts - you have no worries there.

    The number of poles is the number of separate contacts the connector has. Although you only need 2 poles, or 2 wires, 1 (red +) and 1 (black -) to connect to the speaker, you might consider buying the 4-pole Speakons just because they're more commonly used by other speaker manufacturers, even when they don't need 4 wires inside their cabinets. That way you will have a cable that's good for more than just one function.

    From your photos, it looks like you have everything you need except for a mating pair of Speakon Connectors. This is what I would buy (4-pole).

    Speakon NL4MP-ST Panel Mount Male
    Speakon NL4FX Cable End Female

    Speakons with set-screws will accept wire as large as 11AWG with no problem, so 12AWG is a good choice.
    Wire size for the solder-on versions would only be limited by good judgement and your soldering skills.

    Add the Speakon Cable End to the existing 1/4" 12AWG speaker cable shown in your photo. (cut to length, wire strippers, #2 screw driver) - no soldering or special tools required.

    Add the Speakon Panel Mount to the end of the loose wires (red/silver +) and (black - ) Slide those flat disconnects on the appropriate tabs on the speaker (red to red / black to black if they're marked - it looks like there's a hint of red on the one tab) and you're done. All you need is the Speakons.


    Attached Files:

  13. vince latulippe

    vince latulippe Active Member

    THANKS YOU !!!!! :biggrin::biggrin::biggrin::biggrin::biggrin:
  14. Kapt.Krunch

    Kapt.Krunch Well-Known Member

    Just a couple of things:

    "Phone plugs/jacks were not originally meant for power."

    But, they are used on nearly all guitar and many power amps, anyway. Just make sure they are of high quality.

    "They short when you insert them,"

    Yes, the tip will short against the sleeve while inserting. It's ALWAYS a good idea to NEVER connect or disconnect a speaker cable from either end (amp or speaker) while powered up. Having said that, IF having to do so (for some lazy reason) connect the cable to the speaker FIRST, and then into the amp. The reason is that the speaker is not passing a signal, so it doesn't care if the tip and sleeve gets shorted while inserting into the amp. By the time the plug reaches the tip prong, the shorting area should be passed on a standard TS 1/4" jack.

    One other thing: "NEVER unplug either end of a speaker cable from a powered up TUBE amp!! NEVER!"

    Plugging into a live amp first, and then the speaker, WILL result in an electrical short of the amp's output at the speaker end. The safest thing is to power off before doing ANY plugging, unplugging...no matter what connections you do. There are other considerations, including blowing speakers with POPS! Just don't do it at all.

    "They have small contact areas.." True. It's a circle on a flat contact. Other connectors provide more surface area, which can theoretically transfer more power cleaner, and be less prone to intermittent internal disconnection by weak and worn components, or grunge.

    So, why do they keep putting 1/4" jacks on amps and speakers, at all? You tell me.

    When I replied at first, it was just to let him know that might not be the best way, and help him visualize what he was doing. I proposed a cheap'n'easy fix, but the Speakon is better...even though the amp will have the weakest-link 1/4" output. This is just to fill in a couple more explanations for anyone who may not realize why Bouldersound wrote what he did.

  15. bouldersound

    bouldersound Real guitars are for old people. Well-Known Member

    Okay. Because guitar and bass amps, as powerful as some get, are generally lower power than PA gear. And, well, we're dealing with guitarists here. An unfamiliar locking connector may just be too much for a lot of them to deal with.
  16. vince latulippe

    vince latulippe Active Member

    So, anyways, i went to my electronic shop and bought these:


    is the soldering on the speakon plate is the same soldering as anything else ? i have to tin the wire and then solder it to the 1+ and 1- ?
  17. dvdhawk

    dvdhawk Well-Known Member

    In response to your PM:

    Yes, those should be just fine. They make a Panel Mount with set screws similar to the cable end. They don't require soldering, but they're a little harder to find. If this is what they had at the local shop, this will just require some soldering. They make disconnects that slide over those blades, but I don't think they make as good of contact as they will if you solder the wire right to them.

    Since this SpeakOn version is essentially all plastic you have to be careful not to get it too hot. I believe on projects like this, it's better to use a hotter (high wattage) iron for a second to two - rather than a cooler (low wattage) iron for 15 seconds to achieve the same temperature. Give it a minute to cool down between hits with the iron. I keep an adjustable benchtop soldering station and several irons of different wattages, for just this reason. [100w gun, + 45w, 30w, 25w, 12w pencil type]

    If you're having trouble getting the solder to stick, you may need a very thin film of flux paste on the tabs. If you don't have any, maybe the electronics shop could help you out (either with a tiny dab of flux paste, or by soldering it on for you). If you intend to do much soldering it's very worthwhile to buy some. If greatly increases the bond to shiny new metal surfaces. [just keep the area ventilated, the solder & flux fumes aren't good for you]

    Twist the strands neatly together and tin the wire (a tiny bit of flux won't hurt here either). Then with a toothpick or scrap of wire, brush a very thin coating of flux paste on the side of the tab you intend to solder the wire to. Common sense (and good electrical practice) would dictate it should be toward the outside (the side toward the numerical 1+ and 1- markings) to keep the wires and their electrical potential as far apart as possible. Then heavily tin the SpeakOn tab with a good thick dome of solder. Let it cool for a minute, then heat the dome of solder on the tab to liquid form again and immediately put the tinned wire into it. Take away the heat and hold the pieces perfectly still until the molten solder solidifies. Once it's cooled off, you should be able to pull firmly on the wire without it coming off the tab.

    If the SpeakOn contacts are going to be exposed to anything that could potentially short them out, I like to either use heatshrink tubing or a metal electrical box over the back to protect the contacts - depending on the circumstances.

    Good luck.
  18. Kapt.Krunch

    Kapt.Krunch Well-Known Member

    So you're saying...after all that...a 1/4" TS jack would have worked just fine, after all?:biggrin:

    And that swipe at us guitarists...payback for all our drummer, bassist and keyboardist jokes, perhaps?:redface:

    As a historical note, remember the old Vox amp/cab connections? XLR. How many cables did we all modify to make non-Vox heads work with Vox cabs, and Vox cabs work with non-Vox heads?

  19. bouldersound

    bouldersound Real guitars are for old people. Well-Known Member

    Heh. I'm saying that manufacturers have things to worry about that the OP doesn't, like not scaring customers off with unfamiliar connectors. And I am a guitarist, or I was once upon a time. Yeah, there was a time when the best option for a locking, non-shorting connector was the XLR. They usually reversed the gender so you couldn't plug a mic into a speaker. Of course that meant you could plug a mic into the amp's output so I don't know how that really helped.
  20. vince latulippe

    vince latulippe Active Member

    i tried every way to solder my cable to the speakon conenctor but it just won't stick. i have some flux but it just won'T stick. and by the way, it's not the first time that i use an solder iron lolll
Similar Threads
  1. patrickmerrill
  2. JamesG
  3. slamjam
  4. cheetah
  5. Highbrid

Share This Page