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Derek82
08-01-2018, 07:07 PM
Heya guys,

I'm looking at doing my own cables in the future but in Aus nice jacks like switchcraft are expensive in all the places I've seen.

What do you guys use for plugs and cables and what do you pay?

Cheers,
Derek.

Sent from my Moto G (5S) Plus using Tapatalk

Simon Barden
08-01-2018, 07:21 PM
I have leads that use Neutrik jacks and Van Damme Pr Grade Classic XKE cable, though I've given up making them as I can buy well-made ones from eBay for a similar price to doing it all myself. A 5m lead with a Neutrik Silent Plug on one end costs just under £20 here in the UK, that's around Aus$34 at current exchange rates.

From this outfit. https://www.ebay.co.uk/itm/SILENT-Neutrik-Guitar-Jack-to-Jack-Lead-Van-Damme-Cable-1m-3m-6m-5m-Electric/171235837682?hash=item27de7386f2:m:mTwJIWQkV-RQ0h55xMNHh_w

Simon Barden
08-01-2018, 07:33 PM
Though I did make up 15 new patch leads for my pedalboard a few weeks ago and used Hicon 'pancake' jacks and Cordial cable sourced from Thomann. Jacks are just as good (if not better) than Switchcraft. https://www.thomann.de/gb/hicon_flunderklinkenstecker_winkel.htm and https://www.thomann.de/gb/cordial_cgk_175_sw.htm
I did end up having to move some of the tabs in the jacks with thin pliers so I could get the cable through the holes (and had to trim a few wires off each core before tinning the end in order for the cable to fit though the holes) but I'd have had that issue with any make of jack, a lot of which don't have holes in the tabs.

After measuring, I found out that the pancake jacks are the same size (within 1mm) as right-angled jacks, so aren't of much benefit in being able to get pedals closer together on the pedalboard as I'd thought.

DrNomis_44
09-01-2018, 10:38 AM
There's actually two types of plugs that I use to make all my cables, there's a right-angle one and a straight one, both bought from my local Jaycar Electronics store, here's a pic to show what they look like:

24021


For cabling, I usually buy around 10m of Response WB1530 cable, again from Jaycar Electronics, it is actually described as twin-core shielded mic cable for use with 3-pin XLR plugs but I found that it works perfectly well for making instrument leads, I normally just solder the two inner cores together at both ends of the cable and then solder them to the plugs tip connection after soldering the shield-braiding to the sleeve connection.

The plugs I buy are around $6.00 each, yeah I know that's a little expensive but you're better off paying the money for good quality plugs in the long run cause cheap ones will let you down, usually right in the middle of that nicely prepared solo you've been working on for months.

I don't think I've ever done a mini-tutorial on making instrument cables, so maybe that might be a good idea for a new thread to start in the pedals section, let me know if any of you are interested in me doing one.

churchie
09-01-2018, 05:17 PM
I've been thinking about making patch leads too. Otherwise it's those cheap awful ones, solderless kits (and their range of problems) or ones that seem too expensive.

I'm sure I can make them cheaper.... maybe not

Simon Barden
09-01-2018, 05:57 PM
Some of the solderless kits are OK, but expensive. All the Planet Wave's patch cables I made up tested out fine and have been reliable. I've written elsewhere about the problems I've had with George L's cables and high resistance signal paths, so I'd definitely avoid those.

Marcel
09-01-2018, 06:34 PM
For cabling, I usually buy around 10m of Response WB1530 cable, again from Jaycar Electronics, it is actually described as twin-core shielded mic cable for use with 3-pin XLR plugs but I found that it works perfectly well for making instrument leads, I normally just solder the two inner cores together at both ends of the cable and then solder them to the plugs tip connection after soldering the shield-braiding to the sleeve connection.

I usually do it differently when using two core and shield cable on a TS plug (TS= Tip & Sleeve). I chose one core to be my active and tie the other core to the shield. Main reason being that the two cores are designed to carry the signal in under all circumstances whereas the shield in a shielded pair cable is only there to reduce RFI and induced hum and is typically not for carrying signal currents. For that matter when using shielded pair cable on a TS to TS lead I often terminate the shield at only one end and mark the lead where the shield is terminated as the 'Source' end. It is common practice in all forms of Pro audio and broadcast on any shielded pair cables to terminate any cable shield only at the source, however common domestic (RCA type) hifi audio systems and singe core guitar leads typically use the single core shield as an earth return thus the shields are always connected at both ends.

On a TRS to TRS lead the three are always wired with one core to the T, the second core to the R and the shield to the 'sleeve'... (TRS = Tip, ring & sleeve).

XLR (or Canon) connector in nearly all possible uses/cases (audio & DMX lighting) - pin 1 = Shield, pin 2 = -ve, pin 3 = +ve...

Simon Barden
09-01-2018, 07:07 PM
XLR (or Canon) connector in nearly all possible uses/cases (audio & DMX lighting) - pin 1 = Shield, pin 2 = -ve, pin 3 = +ve...

Err, it's normally pin 1 = Shield, pin 2 = +ve, pin 3 = -ve.

Though as long as the shield goes on pin 1 and pin 2 goes to pin 2 and pin 3 goes to pin 3, then the cable will work. Even if 2 and 3 get crossed over, then it will still work, but you'll get a signal with a reversed polarity.

DrNomis_44
09-01-2018, 07:40 PM
Hence the reason why I use the continuity test function on my Digital Multimeter to give all my newly-made cables a good health-check, if they pass all the health-checks I put the new cable into service, if they don't pass I usually get straight into sorting them out.

Marcel
10-01-2018, 09:15 AM
Err, it's normally pin 1 = Shield, pin 2 = +ve, pin 3 = -ve.

Though as long as the shield goes on pin 1 and pin 2 goes to pin 2 and pin 3 goes to pin 3, then the cable will work. Even if 2 and 3 get crossed over, then it will still work, but you'll get a signal with a reversed polarity.

Phase... symbolised on many bits of gear by the Greek letter Theta, a lower case "o" with a "/ " through it. (I can't find the right keystroke to bring it up on screen).

On a XLR to XLR cable it only matters that pin 1 goes to pin 1, pin 2 goes to pin 2 and pin 3 goes to pin 3. In all cases it we have the shield to pin 1 and the two cores to pins 2 & 3. The electrons don't care what colour the plastic coating on the wires is, just that they get to a destination, so it becomes a decision by the cable builder as to which colour wire goes to pin 2 and which goes to pin 3. Many of the cables I use have Orange & White or Red & Black So I choose to have the Orange or Red wire going to pin 3, however Simon would most probably put them on pin 2. It doesn't matter, so long as both ends of that cable are consistent.

If we have two XLR to TRS leads that are used to go from a mixing desk to say a rack mounted Lexicon effects unit and back again, being consistent and using only cables built to only one of the two wiring conventions the phase of the signal is maintained correct at our mixing console by the consistent wiring convention used and the phase through the Lexicon device really doesn't matter.

The problem comes when we have a reversed phase XLR to TRS or TS lead in the signal path of say a system like a PA system. Again, if all are to the same wiring convention of +ve on the same XLR pin everywhere there is usually little issue. However, if we say have a PA that uses active crossovers for bass/middle and high frequency speakers and somewhere in one of our speaker stacks wiring we have a XLR to TRS or TS (or even an XLR to XLR or a TRS to TRS) that is reverse to all the others then those cabs will be pulling when all the other speakers are pushing we will have two huge problems. One, our system will simply just sound wrong. Our amps will be peaking but we just don't have that chest pumping volume because one set of speakers will be working against the others and cancelling out the sound. And two, we will get feedback which we won't be able to control or get rid of as no matter what we do (hitting the phase switch on the console or adjusting EQ) there is always a speaker somewhere that is in phase with some open microphone on stage causing the feedback. The biggest issue here is wiring inconsistency within that system.

In broadcast and in the recording studio it is less of an issue as feedback is encountered far less often. But it can be a problem for certain effects processors and signal conditioners as they may require the dynamics of a signal to be presented or used in a certain way. An example being in broadcast radio where just before the transmitter many stations employ the use of an Orban Optimod which is a device (much like a PA system active crossover combined with a multiband compressor) that conditions the broadcast audio +ve and -ve voltage values perfectly for the transmitter it is attached to. Reverse the phase of that signal and the station will sound horribly wrong...

In any single guitar rig it is far less of a drama. Most guitarists will get used to what they have, but if a (pin 2 to pin 3 phase swap) change is made then the guitarist will certainly notice. Amp sustain and amp feedback in any given situation will certainly be different. Which is probably why XLR's and TRS's are rare in a guitarists rig, and in practice there is only one reasonable way to wire a TS plug.

In all honesty I'll say Simon is right with +ve on pin 2, but that's not to say that I was wrong with +ve on pin 3. If Simon and I were to each build similar PA systems both would work and both would work well. The huge problem of 'phasing' would only come if roadies hired a system from one of us and then got extra gear from the other and then mixed up the XLR to TRS or TS leads.... An unlikely scenario as Simon is in the UK and I'm in AU...

DrNomis_44
10-01-2018, 10:43 AM
I seem to remember a set of plug wiring-conventions set-out in one of my Jaycar Electronics catalogues on one of the pages with data and some schematics, I need to get myself a new and up to date copy of the catalogue anyway, so once I do, I'll put together a set of hand-drawn diagrams showing the correct wiring up for the different conventions, something I think should prove to be useful.

Derek82
10-01-2018, 03:30 PM
I seem to remember a set of plug wiring-conventions set-out in one of my Jaycar Electronics catalogues on one of the pages with data and some schematics, I need to get myself a new and up to date copy of the catalogue anyway, so once I do, I'll put together a set of hand-drawn diagrams showing the correct wiring up for the different conventions, something I think should prove to be useful.Thanks so much for the replies guys. Interesting stuff that I knew (and probably still do) know squat about.

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Simon Barden
10-01-2018, 06:05 PM
No, the correct term in this instance is polarity. This is an issue that comes up time and again on the Sound on Sound forums. Phase is time related and unless it's a single frequency sound, within milliseconds, the phase relationships between different frequencies are all changed. But in terms of polarity, a swapped polarity signal will always look like the inverse of the original signal. It's slightly pedantic, but swapped/inverted/reversed polarity is the technically correct term here.

And it often does matter about the pin connections on XLRs. At some time in the past, some countries used pin 2-ve, pin 3 +ve, whilst other used Pin 2 +ve, pin 3-ve. Obviously this caused confusion, so it was standardised as Pin 1 shield, Pin 2 +ve, pin 3-ve. This can catch some people out with old equipment.

It's all driven by microphone outputs. It's standardised so that a positive pressure on the mic diapragm causes a positive signal on pin 2 and a negative one on pin 3. This convention is then followed through all other connected equipment so that a positive signal on pin 2 of the mic caused a positive signal on pin 2 on the output of a connected mixer which caused a positive signal on the 'positive' output of a connected amplifier, and then a positive pressure to be produced by the attached speaker.

But knowing what pin is +ve does make a difference when you need to connect balanced to unbalanced equipment (and vice-versa). Without doing it correctly and connecting pin 2 to the tip of a TS jack, you will reverse the polarity of the signal.

Paul_H
10-01-2018, 08:06 PM
Rane Corporation did a great white paper on audio interconnects: http://www.rane.com/note110.html

And just a minor point regarding the Greek symbol for phase... I believe it is Phi (not Theta) ø

DrNomis_44
11-01-2018, 12:25 PM
You can also measure phase on a device called an Oscilloscope, in this case the phase is measured in degrees and is called the "Phase Angle", if you have one signal which is your reference signal and an identical but opposite-in-phase version of the signal, the opposite-in-phase signal will be 180 degrees out-of-phase with your reference signal, sorry if this is sounding a bit technical, now, if you add your reference signal and the 180 degree out-of-phase together both will cancel each other out and you will be left with nothing, this is assuming that both signals are identical and opposite-in-phase to begin with, this is also essentially how the XLR cables (called "Balanced-Cables") work to suppress hum and noise pickup.

Basically the theory goes like this, if the two signal carrying wires in an XLR cable pick up any noise and,or, hum then that noise/hum is going to be in-phase whether it is on the in-phase signal wire, or the 180 degrees out-of-phase wire, where the two signals arrive at the input of a device that the XLR plug is plugged into is when the magic happens, inside the device is some extra circuitry connected to the 180 degrees out-of-phase signal input, this extra circuitry "flips" or inverts the signal so that it is back in-phase with the other circuitry, but it also at the same time inverts the phase of the noise signal, so when the in-phase noise signal is added to the out-of-phase noise signal they cancel each other out and you are left with the signals that you want to hear.

DrNomis_44
11-01-2018, 12:53 PM
Rane Corporation did a great white paper on audio interconnects: http://www.rane.com/note110.html

And just a minor point regarding the Greek symbol for phase... I believe it is Phi (not Theta) ø


Definitely a very useful website, I'd recommend everyone bookmarking it for future reference, and also download the pdf as well, cheers Paul_H.

Paul_H
11-01-2018, 04:05 PM
As Simon has mentioned previously, I think it is more correct to refer to polarity when considering differential signals. Phase differences also imply time differences in a signal, whereas in a differential pair one of the signals is inverted without a time difference.

Balanced lines, however, do not need to carry differential signal, since the "balanced" refers to each line having equal impedance to ground. One practical implication of this is that unbalanced gear may be modified to provide a balanced output with as little as a resistor, a capacitor and a suitable connector.

Marcel
11-01-2018, 07:16 PM
Polarity is correct.
Phase is correct (but only under specific conditions defined elsewhere)(not limited to 'time' differences)

It's a bad habit of mine to use less specific words, and then sometimes have to go back and explain myself.... you can also read it as "but that was automatically implied by the context of the ..." which for me as a working audio/radio/guitar/stage lighting/microwave/TV/VCR/studio/computer/turntable repair tech the 'context' can change nearly every other job or paragraph, as does the usage of various pins on some multi pin connectors.

Quite often in my work it is a case of getting accustomed to one 'standard' (usage, implementation or meaning) and then discovering that a dozen or more other 'standards' can also apply.... For example there are also 'standards' for the humble 3 pin XLR that define for single and dual loud speaker use (as was often done on Aussie Rock-n-roll PA systems in the '80's) as well as for DC power use (12V/24V & the much better known 48V phantom power) and then there is the vintage '50's radiogram bits of gear that have their own uses and ways of doing things with those XLR pins that are rated to and can carry 15A each., so it can be quite easy (as it was in my case) to only remember the first of each type of 'standard' that you were first introduced to, or maybe simply the standard you used the most....


A conversation spanner I'd like to throw for the amp builders among us here is this ....
3 pin XLR pins are rated at 15A continuous, (21A peak <1mS)
4 pin XLR pins are rated at 10A continuous. (14A peak <1mS)
5 pin XLR pins are rated at 7.5A continuous (10A peak <1mS)
TS is rated at 5A continuous (7.5A peak <0.1mS)
TRS is rated at 3.5A continuous (5A peak <0.1mS)

So a TS jack so typical of most guitar amp speaker connections is a convenient connector but can be pretty stressed on a 100W amp at max volume... and PA systems of the '80's were not wrong back then in using XLR's for speaker connections on PA amplifiers rated 450W RMS per channel at 8 ohms.

With P=EI and E=IR etc... and the maximum continuous amp ratings of our connectors...
When using a TS plug gives us a max permitted power of 225W on a 4 ohm load, or a max of 112.5W when using a 2 ohm load.
When using a 3pin XLR we can have a max of 450W on our 2 ohm load, or a maximum power of 900W being passed through the XLR into our 4 ohm speaker load...
Obviously nobody has said anything to some pro mega bass amp/cab builders... or maybe it's they just don't care...

Simon Barden
11-01-2018, 09:46 PM
I heartily agree on TS jacks being very limited for speaker connection usage and 100W being a reasonable upper limit. All my higher powered cabs have Speakons fitted.

Marcel
11-01-2018, 09:54 PM
Yep, Speakons remove all the speaker lead confusion for roadies... but puts them at odds with the lighting guys with their very similar Poweron connectors ... lol