GK-13 Pin Cable FAQ

Started by Elantric, November 19, 2008, 11:44:28 AM

Previous topic - Next topic

0 Members and 2 Guests are viewing this topic.

whippinpost91850

what do you mean slightly smaller and a bit bigger ???

fokof

Smaller in lenght , bigger in diameter.

I don't have it with me now , I'll post the exact mesuring.

Eight_Stringer

Hello Elantric and all,
       As mentioned it is information that may be useful at some time for others.  If i understand you correctly about single point termination shield on the Roland GK13 cable assembly,  this is the correct way to provide best outer shield action,  and reduce  voltage gradients along the cable length, ie current loops ( oft quoted "earth loops" ),  it is the current in these loops that causes the unwanted signals and induced noises.  By terminating the shield at one end only there is little support for a current to flow.  Apologies if i have not understood the reference to shield termination correctly.

  The cable assembly from the hex pickup to pcb is also single ended terminated for the shield with the black wire providing the return path for all 6  pickup assemblies. This black wire is joint terminated with the connection header on the pcb copper foil.

  As for the protective "film" for connector pins,  this has been a long tradition in industrial connectors and assemblies.  Not widespread of course,  yet a good move in the great scheme of things,  just you would like to know before you use the assembly,  this forum is a great help in that regard.
Cleaning can be a two part process, harsh chemical strippers such as ( in Australia CRC CO contact cleaner ) strips all films and oil residues, the later action depletes moving parts ( and connections are moving parts ) from long life assisted,  reduction of friction.   As required here i strip/clean with CRC CO and lubricate with CRC 26-2  after stripping.  Some plastics can be degraded by these chemicals,  hence care is required in test application.

   Hope that helps,  Regards.

Elantric

#28
However, the "Achilles' heel" with the Roland GK13 DIN cable design / implementation is that a few manufacturers use  a female 13 pin DIN jack with a very poor contact connection to the crucial GROUND  - which only occurs on the circular Shell connection.

The 13 pins always have a more robust electrical connection, but the connection to the circular shell is often very marginal on many DIN13 jacks.


The GK-3 has a voltage on Pin #9, but all prior 13 pin GK pickups (Roland GK-2A, Axon AIX-101, Yamaha G1D, RMC, Ghost piezos, etc, ) leave pin #9 open as a spare connection.
Read other gear that uses Pin#9
https://www.vguitarforums.com/smf/index.php?topic=5259.0
We have already covered that a few folks have modified their gear to implement pin#9 as "Analog Ground Reference Return" path. True on paper this may appear to be potential source of Ground Loop noise, in practice quite often using pin #9 as a analog Ground return path provides a more trouble free / less prone to static noise cable connection at the gig.

reference
https://www.vguitarforums.com/smf/index.php?topic=3857.msg26085#msg26085

DrJoness2001 wrote >
QuoteI used to wire my GK-2A guitars and synth (VG-88) with pin 9 as ground. I hated the jack/shell ground. I wish there was a dedicated pin for ground. The old Roland 24-pin gear had four wires for ground!

Eight_Stringer

 Can see your point Elantric,  DIN connectors are not my first choice in non domestic applications. I rate our usage as industrial grade. Many other connectors would have been more suitable, even a D15 ( vga style ) would be ideal, allowing extra pins for future upgrades, plenty of high grade monitor cable available would have thought.  Design is of the moment, often the moment takes a wrong turn/choice.

  As to the GK3 cable connection scheme, it is worse than you describe. There is no local Zero Volt connection for the balanced supply rails. It is through the shield and contact arrangement on the input connectors, either end. Correct me if i am mistaken.  This is worst possible choice as it now mixes DC current with ostensibly AC ( signal ) current,  added with an unreliable contact arrangement and you have unhappy end users,  am in no doubt.  Also the filter capies for the supply rails are only bypassed with low ESR capacitors,  great in theory and poor in application. These should be bypassed with smd 0.1uF ( and 1nf if possible ) capies to ensure a best approach to AC gain characteristics  for the op amps and associated circuitry. 

   Really is a case of young engineers not gaining historic engineering to bring about predictable and well proven outcomes.  No point in using high end op amps in an application and cripple the device with poorly engineered AC circuit networks,  external.  A properly designed supply rail will perform as good or better than a battery.  The latter requires step/staged capy bypassing even more so than a rectified supply circuit.  Time and again i see battery operated devices,  relying on the batteries low internal impedance to provide correct AC gain on the supplied circuits.  The battery is anything but low impedance, known for the last 100 years,  news to some it seems however.  Billbax uses batteries as i understand it, he has his requirments for ultimate performance, common mode and normal mode rejection ratios would be hard to control with a usual PSU arrangement, especially smpsu designs.

Regards to all.

Guilded

I had a terrible microphonic noise in the 13 pin cable at the GK3 connector when it was new, right out of the box. I picked up some electronic contact cleaner, did what the thread said for preparing the cable and NOISE WAS GONE. Simple but worked like a charm.

Much thanks!
Jake.

audiotrax

A couple times a year I get that.  Just shoot some WD40 into the plugs on either end of the cable (NOT directly into the VG!), then work them in and out of the connectors on your GK devices.  Also make sure to apply some on a course rag and work it around the outside of the cable plugs.  Fixes the bizzare microphonic problem everytime.
Owner of: VG-88, GI-10, Cubase 5, Kontakt, SampleTank, var VSTI's, Roland JV1080.  Strat with GK-2A, two Roland GR500 analog guitar synths

alexmcginness

audio trax....thanks I tried it and it worked. I foun my problem was the connector on the GK. I sprayed some contact cleaner into the plug and into the gk socket as well as on the 99 and voilla ...noiseless.
VG-88V2, GR-50, GR-55, 4 X VG-99s,2 X FC-300,  2 X GP-10 AXON AX 100 MKII, FISHMAN TRIPLE PLAY,MIDX-10, MIDX-20, AVID 11 RACK, BEHRINGER FCB 1010, LIVID GUITAR WING, ROLAND US-20, 3 X GUYATONE TO-2. MARSHALL BLUESBREAKER, SERBIAN ELIMINATOR AMP. GR-33.

fokof

The one on the left is the one sold by Carvin , on the right is a standard Roland cable.

gumbo

....the 'smaller' plug is identical to the one I was referring to in:

GK-13 Reference Library / Re: where to buy "small" gk cable ?


...when I talked about those available (separately) from NKC...


HTH someone..

Regards,
gumbo
Read slower!!!   ....I'm typing as fast as I can...

fokof

I think the guy was talking about the lenght of the cable itself , not the plug.


Anyways I just wanted to share this info to anyone looking for other GK cable suppliers.

sharris

#36
I have a 15 foot 13 pin synth cable that came with my GR-55. I was looking to buy a longer and a better quality one than the stock model. In my opinion the cable seems cheesy and fragile. If I ever accidentally stepped on a end it would surely get munched. Does anyone know if metal ended 13 pin cable exists? I'm not referring to the metal collar that houses the pins but the plastic cannon piece around that and the cable. If so, could they provide me with a few direct links to pages where I could purchase one?

Here's all I found on google. All have the plastic ends:
http://www.musiciansfriend.com/accessories/planet-waves-13-pin-midi-guitar-synth-cable
http://www.sweetwater.com/store/detail/GKC10
http://www.carvinguitars.com/products/single.php?product=C20P13&cid=45

Thank you.

Elantric

#37
I'm NOT aware of any metal jacket  13pin DIN male plugs which exist  that also include the important Roland 13 pin Cable Lock mechanism on the Male Cable plug end.


sharris

Thanks for the info Elantric!  :)

tomslad

Hi everyone this is my first post on these boards and I hope this may help. I have just bought my Gr55 and I am well pleased with it but on the second occasion that i used it I got the horrible noises when the cable was moved or touched and I was concerned that I had a faulty unit, on this particular occasion I had connected the cable into the GR55 and powered up but hadn't yet connected the cable into the guitar which I then did after powering up.it was at this point that I noticed the problem with the cable being touched or moved.I powered down and connected all cables before powering back up and there was no problem. I now connect everything first and have never had a repeat of the problem.

papabuss

#40
Hi
I must really confirm your points..
I've never had any problems with my VG 99 ...then often had problems using the same GK 3 cables with the GR 55..I often could solve the problem by disconnecting the cables...(not a could solution as I wrote some time before)
FENDER STRATOCASTER (1974); BRIAN MAY RED SPECIAL; VG 99; GR 55; Yamaha DX 7

Music was my first love and it will be my last (JOHN MILES)

Machh_2

#41
if your interference sound like a humming or "bzzzzzzzzzz" probably is 60hz noise, if in some position the noise increase or decrease, is because guitar is working like a antenna for interferences.
if u use cold lamps on your room, like as fluorescent lamp with reactors, the high frequence of oscilators on reactors, induces hummings on eletric net and comes to your amp, increased by your "antenna guitar".
try use a line filter, those used to protect computters, but buy a with good quality...or do one your self...on the internet have manys..easy to do.
i do my filter, and works very well, reduces 70% of noises... you can try, worse will not be...

good luck

PS: if you hit the cable on the floor and you ear some "clicks, tiks, " etc... maybe the internal shield of cable is not soo good...maybe is oxided is change the impedance of cable, or the oxid is create some resistance between cables,shields and pins...

Bill Ruppert


Jim Williams

The cable issue is probably Something Roland didn't see coming. But the problem can be solved by cleaning your cables often. The problem doesn't exist in just in the cables it is in all male and female 13 pin connections. You have to clean them on a regular basis it is not a one time fix. If you intend on using the GR-55 plan on lots of cable maintenance. Use Deoxit or rubbing alcohol as temporary solution. I believe Deoxit has a special type of oil for maintaining clean audio connections. When my GR-55 was brand new out of the box I didn't get all that noise but it developed as the contacts became dirty. I also experienced this problem with my VG-99, It took a much longer time to occur though. This leads me to believe that the GR-55 is more sensitive to contact corrosion than the VG-99, but the problem does exist in the VG-99. I bought both units as soon as they were available and have used them in every situation possible.
Skype: (upon Request)

Everything from modeling to the real deal, my house looks like a music store.

billbax

#44
Hi,

Crackles and creaks are obviously 13pin connector contact noise.  That's 14 connections if you include the screen/shielding, and a lot to go wrong.  The swishing sound when moving a cable across the floor using a high-gain patch, is the dreadful inadequate copper and cotton screen.

If the GK cable was properly doubled-screened and the connectors soldered and not crimped, then 90% of the mentioned problems would go away.  Saying that, the cable would be a lot more inflexible and expensive to make. Definately a good trade-off for the studio...Live...don't know. 

Bill

www.separate-strings.co.uk

fly135

I'm familiar with the TS problem because I helped him test it.  I even replaced the 13 pin connector on his guitar (hex pup built in) for him.  We were seeing the problem even after that and could get noise while shaking the cable lightly while the connector ends were stationary.  Ultimately we think the issue is the cables he had.  I just picked up a new GR-55 with GK3 and cable from Hello Music and it's working fine.

Machh_2

I have 2 units GK2A and GK3, and i have 2 13 pin cables, one this cable is from GR50 (around 1990), and the new cable and GK was buying 2011/12, both pair GK/Cable do noises when shaked.

i think than the problem is 2 things:

1 -  the shield cable is a big big crap.
2 - even adjusting the gain at low levels in GR, the gain is still sufficient to capture noise coming from the cable.
The copper of the cable is oxidized easily by changing the impedance of the cable, facilitating the inflow of noise.

I believe that there really is a problem with the cable impedance.
In my humble opinion, these cables are very thin, and changes the signal transfer between GK and GR.
The input impedance of GR is already high, which demands that the cable has a minimum impedance to the drive signal for the integrity of the GK GR, maintaining the signal to noise ratio in good condition.

Added to this a bad shielding, so you guys can imagine how the problem is.

Green Lantern

#47
The title basically says it.

I have two GK guitars. One is a Fender Roland Ready Stratocaster, the other is a Gibson SG Special Faded that I put a GK-3 pickup on. The Strat always works fine, but sometimes the high e string will drop out on the SG. The weird thing is that I've learned to fix this problem every time by plugging into and out of the headphone jack of my GR-55.

Does anyone have any idea what could be causing this problem, how I can permanently fix it, and what the headphone jack has to do with any of this?

Thanks a lot in advance.

Elantric

#48
I suspect you have intermittent contacts on your 13 pin cable, and unplugging  / plugging in the Headphones on the GR-55 is simply creating vibration that solves the intermittent connection.

Clean your 13 pin cable - details here:
https://www.vguitarforums.com/smf/index.php?topic=3132.0   

Quote from: fly135 on January 19, 2012, 09:15:58 AM
I'm familiar with the TS problem because I helped him test it.  I even replaced the 13 pin connector on his guitar (hex pup built in) for him.  We were seeing the problem even after that and could get noise while shaking the cable lightly while the connector ends were stationary.  Ultimately we think the issue is the cables he had.  I just picked up a new GR-55 with GK3 and cable from Hello Music and it's working fine.

The free GK cable included with GR-55GK is among the worst examples ever produced

Green Lantern

#49
That would seem to be the most likely thing, but I've tried it with two different cables, and two different guitars. The cables seem to be fine (and I've cleaned them pretty thoroughly), as the same thing will happen with both of them, but won't happen with my Roland Ready Strat. If I had to narrow it down to anything, it would be the GK-3 on my SG. Next time it happens, I'll try plugging into some of the other jacks on my GR-55 and see if that fixes the problem. It is certainly mysterious.