Ribbon cables in Patchbays?

[porkyc]

I worked for Harrison for 20 years. This is how the Series10, series 12 and MPC were all connected, using the 3M screened ribbon. (See Brian Roth pictures).
With everything balanced in/out this cabling was never a problem and we had analog consols with over 200 channels (film boards). They were screen/ cold/hot across the ribbon to Harrison pinout (reverse of Tascam), because the mesh shield was pin1 of the ribbon. Have no fear.

 

[Murdock]

Thanks for sharing your experience.
But my ribbon cables are not shielded and shielded ribbon cables are damn exspensive ...

 

[abbey road d enfer]

Thanks for sharing your experience.
But my ribbon cables are not shielded and shielded ribbon cables are damn exspensive ...

I have used adhesive copper foil for that.
https://www.banzaimusic.com/copper-foil-100mm-adhesive-1m.html

 

[porkyc]

Forgive me, I was under the impression you were concerned about using unshielded ribbon in the manner you had illustrated; not as part of a full installation into the outside world as per Brian's pictures.

 

[Matt Syson]

As Paul commented a few posts back, don't 'stack' your ribbons unless you have taken care to have shielding between each ribbon (like the copper mesh inside the very expensive commercially available ribbons that Brian pictured (as used by AMEK on several desks/patchfields) with no issues.
Having 'encountered' ribbons in a desk built by another manufacturer that had 'cooking foil' screening I can vouch for it being a bit too 'cheap and cheerful' if you ever have to work with the cables.
Matt S

 

[FIX]

All my outputs are balanced LO-Z and all inputs are balanced HI-Z. so the cable has very little crosstalk if any. I've run as long as 35 feet, and under keyboards with zero detection. Of course, mic lines are shielded cables. You can use that aluminum foil tape on each ribbon if they need to be stacked tight.

 

[Greg Norman]

I figured I'd toss this into the discussion. I was involved with the installation of two GIANT Amek 9098 series desks ("By Rupert Neve, the Designer"), originally made in the 1990's.

The first was in 2003 and was a 72+ input inline, a 9098i. The second was in 2009 and an earlier version which was a "split" monitor desk with 48 full function modules and 48 monitor modules. I also re-installed that second desk when it was sold to a new studio in Mexico City.

Both desks had a large external patchbay system which tied to the desk via a "bazillion" ribbon cables. I am guessing each ribbon was 30' in length. My memory about those cables is a bit fuzzy, but I believe each ribbon had an overall shield beneath an outer sheath.

I've attached a couple of snapshots. The first one shows the control room in Mexico City with the patchbays in the rear wall. Gives an idea how long the ribbons had to be to route through the walls/floor. The second pic shows the ribbons sitting on the floor of the tracking room as I pulled them all out of the control room here in Kansas before packing them up for shipment to Mexico City.

All I can say is this was the Amek factory design for both desks which originally sold for well into the six figures (US$) and both desks seemed to work quite well. I also attached a sales brochure for the 9098i but it doesn't mention how long the ribbons were....perhaps an option ordered at purchase.

Bri

I recall a friend/tech in Chicago discovering a problem with the ribbon loom design in the new-from-the-factory 9098i. He made an lengthy, elaborate before and after report, replacing an example section with standard twisted pair shielded cable. After some arguing, the Amek factory techs sheepishly acknowledged the issue as a design weakness, and maybe even offered something for the discovery. I imagine it wouldn't be an issue for most music studios. I forget what the original complaint was. It was installed in a building with multiple business, so maybe it was an interference issue...
Ever since then, I've been on the 'never ribbon' side of the fence. I recognize it's as cheap as dirt to do, and imagine the trade off being significant when wiring a 72 chan console, but for a 1/2 million dollar console? Nah. I don't understand not making things bullet proof at that level.

 

[Matt Syson]

From the previous photos that 9098I desk was using an exceptionally long run of ribbon, certainly longer than other installations I have seen. The Mozart and Hendrix 'remote patch' variants had no problems. Mind you the USA use of 120 Volts mains creates a stronger radiated hum field generally.

 

[Brian Roth]

From the previous photos that 9098I desk was using an exceptionally long run of ribbon, certainly longer than other installations I have seen. The Mozart and Hendrix 'remote patch' variants had no problems. Mind you the USA use of 120 Volts mains creates a stronger radiated hum field generally.

FWIW, the photos I posted were of the ribbon harness from an earlier "split" 9098. But the later 9098i I worked with had a similar ribbon harness that was also quite long IIRC.

Bri

 

[Matt Syson]

I took the prototype/demo 9098 unit to Tokyo with Mr Rupert Neve but then became involved in the DMS digital desks (and all the other analogue stuff) so missed out on the 'joys' of the production 9098 desks.
Matt S

 

[FIX]

An overall shield 30' long may create more issues with capacitance than shielding... With true balanced lines (keep in mind that phone lines on poles had 50 pair within one shield, and if terminated correctly and the CMMR was good, their was no interference, and in the early years of data, they had a lot of pure tones warbling on them. I have never in my life ever heard a cross talk modem on an old phone). If you want extra protection, you could put the copper foil on one side and then around them and stack them.

I read a lot of naysayers, but I would like to actually hear if any of them actually had problems, or that it's just theoretical. I use the DA-88 pinout, on crimped Dsubs, keep in mind that a Dsub was designed for HF data and had a reasonable amount of current, and that a knife blade crimp, when matched to the correct wire diameter, has a gas tight connection that is the same as solder.

Of course I would use shielded cable for mic lines.

 

[JohnRoberts]

I've used truckloads of ribbon cable inside consoles and mixers. I will avoid making broad sweeping generalizations but how you use the ribbon cable matters (like how you treat signals in adjacent conductors, etc).

Over the decades I've seen more ribbon cable complaints about faulty header swaged connections (mostly with other console makers). We had our own machine in our factory but as I recall the tooling needs to be periodically inspected and adjusted as needed.

I am happy to report I never had to get personally involved in fixing problems related to this factory operation (a good thing).

JR

 

[boji]

At this point I think CAT6 would be better for a variety of reasons.

Chose Cat6 for outboarding mute/solo cv (retrospectively a costly, clunky idea).
I can report noise performance is excellent running at right angles to shielded fader wires....but was a major pain to route and takes up space.

 

[jazzcrisis]

Chose Cat6 for outboarding mute/solo cv (retrospectively a costly, clunky idea).
I can report noise performance is excellent running at right angles to shielded fader wires....but was a major pain to route and takes up space.

Wow--even used the Soundtools cable. That's some good stuff!