Page 1 of 2

GCX Switcher Troubleshooting

Posted: Sun Oct 22, 2017 9:00 pm
by SharkysMachine
Hi guys,

I've been running a rack rig with CAE RS10 and GCX Audio Switcher for probably 16 years.
A few weeks ago I fired up my rig and the GCX Audio Loops would not switch on - I literally have not changed the programming in a decade. Midi cable is fine - sends power to the RS10 on pins 1 and 3. MIDI signal hits the GCX - the active light blinks - BUT it's a a dead end - nothing after it in the midi chain gets program or controller change messages, and the loop switches/lights do not engage. It's painful to test because the GCX is the only component that provides phantom power over midi.

Two questions -- has anyone out there seen seen this type of failure on old GCX Switcher - this thing has ten thousand hours on it - so no big surprise if a $400 unit needs replacing - but if you've had this problem -- is there a quick fix? - I'm handy with a soldering iron to replace a jack or something - but it would be stretch to troubleshoot failing ICs.

So again phantom power works - signal sends - active light blinks -- midi dead ends and no loops are engaged...
The main suspect is the GCX Switcher, but I can't rule out a bad 3 pin or a failing RS10 either I guess without further testing - which ultimately involves more gear - so I can test...

Thinking I may just get a new one and if it works fine - send the old one to voodoo to get fixed - but wanted to get some weigh in from the house.

Rock on.

Re: GCX Switcher Troubleshooting

Posted: Mon Oct 23, 2017 1:25 am
by bettsaj
Just as a process of elimination..... Can you borrow another midi board to test it with to ensure that it isn't the board? The RS10's are bomb proof, but i guess even they could need some TLC sometimes.

If the signal light is flashing on the GCX then we know you're getting a midi signal into the unit, so it does look like it might be the GCX that's at fault.

Re: GCX Switcher Troubleshooting

Posted: Tue Oct 24, 2017 11:03 am
by JohnClark
I would first make sure that the MIDI programming is still correct. That the GCX Active LED is flashing says MIDI signal is getting to its MIDI In, but it does not tell you what the messages are. An unmodified GCX responds to MIDI Control Changes 80 - 87 on MIDI Channel 16.

I know you say they are not responding to the controller as they once did, but do any of the other MIDI devices in the MIDI path have MIDI activity LEDs or Display elements that indicate MIDI signal? What are the other MIDI devices you are controlling?

Re: GCX Switcher Troubleshooting

Posted: Tue Oct 24, 2017 7:05 pm
by SharkysMachine
There is nothing down the chain after the GCX - it's like the midi signal terminates at the GCX before engaging the loops. I'm going to see if I can find another powered controller - I dug up an old ADA midi controller from the garage but of-course no ada power supply to be found - with luck it'll accept phantom power or a standard barrel connector...

will let you guys know what I find. thanks for responding!

Re: GCX Switcher Troubleshooting

Posted: Wed Oct 25, 2017 12:44 am
by bettsaj
Stupid question...... is the RS10 still transmitting on the correct midi channel?

Re: GCX Switcher Troubleshooting

Posted: Wed Oct 25, 2017 1:09 pm
by SharkysMachine
I think so - like I said I haven't touched the programming in a decade...

Last night test was easy -- the GCX Switcher went from not working to totally dead last night. Wouldn't power up at all.

And it's well protected too - plugged into a Pedal Power which is plugged into a Furman.... The other rack gear had power. Writing this ... I realize I should have checked the pedal drawer to make sure lights were on to rule out the power brick. But that would not address the midi issue - so many cables of audio, power, and midi...

Anyway I ordered a new GCX so hopefully this will end the midi problem.

Thanks for the input!

Re: GCX Switcher Troubleshooting

Posted: Wed Oct 25, 2017 3:10 pm
by JohnClark
Wait... are you not using the original power adapter for the GCX?

Re: GCX Switcher Troubleshooting

Posted: Thu Oct 26, 2017 12:18 am
by bettsaj
What power brick are you using... Is it a Voodoo Lab pedal Power AC?

From what you've said, I'm assuming you're using an AC and one of these

Image ... bban7vpcu5

Re: GCX Switcher Troubleshooting

Posted: Thu Oct 26, 2017 11:25 pm
by SharkysMachine
I am using the original wall wart -- it is plugged into an AC outlet on the back of the Pedal Power. It's looks closes the newer Pedal Power 2 plus - that is plugged into a 1U Furman at the top of the rack -- (no room for a wall wart up there). The Furman is plugged into a power strip dedicated for power amps. So three layers of simple AC protection, glorified power strips all, but better than nothing -- all power amps in the studio get turned off first and turned on last, and my entire guitar rig is in on that power amp strip. In fact everything except the bass amp is on that circuit to avoid loops. AC is ground loops are well managed - although I'd like to upgrade to a better power conditioner to protect the studio gear...(another conversation)

That connector is sweet, but I don't think I need it since the Pedal Power has AC outlets on the back. Good suggestion though.

The Pedal Power is whatever the standard power brick DMC was shipping in the early 2000's when I built this rig. I'll report back when I hook the new GCX up. It arrived today so I'll hook it up this weekend and test everything. Spoke to Ben at Voodoo - he said to send in the old one and they'll fix it. Now I need to get my hands on an RS10 expander and another 4space rack - so I can run 16 loops and hook up more tools and toys...

The gear config described below has 1000s of hours on it in it's current configuration. It's way fun and has been consistent/bulletproof until this year. None of the rack is fresh gear and it's all high mileage and most of it is out of production for a decade or 3. The GCX Switcher still says Digital Music Corporation. Guitar into Marshall JMP-1, Marshall send into buffered GCX input - feed thru to tuner. Loops are Original TC G Major (2 loops), Line 6 Echo Pro (2 loops) - the rack version of the Green Stomp Box, Original Boss DM2, TS9 or EQ7, BF2 or Electric Mistress and PH2 in loops - GCS sends stereo back to Marshall -> main outs to Mesa 20/20 power -> 8 ohms out to 2 Custom A Broun Sound Hemp Cone Alnico Tone Tubby 1x12 Cabinets -- it's a sweet stereo ride ... all of it programmed and controlled with the RS10 and two old - military grade metal Roland expression pedals. I can send different rack effects to left and right with direct access switches - contro/constrain parameters on delays, chorus, flange and phase on the TC and Echo Pro -- the stomp boxes are obviously fixed in their config for specific use. Occasionally in the studio for a specific track I'll drop a Q Tron or Bad Horsie in front. But mostly - nothing changes - Guitar into Marshall -- every Marshall setting is 100% wet - only the old DM-2 shows volume suckage, but the sound is so good I just pair it the EQ7. If I'm running no loops it's marshall, mesa, tone tubby...all tones decay sweetly with program changes, never had a click or a pop once. It been like a trip on the Rocinante for nearly two decades.

BUT this year I've had gear failures for the first time. Marshall master volume, TC LCD display, GCX switcher grizzly death --
When the TC fully goes -> Eventide Eclipse will go in and months of programming begins.

I have other pedal brigade rigs set up too - and tonally they compete - but not in terms of flexibility, ease of use and consistency. Love me some midi managed racks.

The two custom jobs are the RS-10 which Bob did some extra stuff for me on - and the speaker cabinets -- both of those were built to spec. The rest is just old stock gear. With miles of cable....

Re: GCX Switcher Troubleshooting

Posted: Mon Oct 30, 2017 7:38 pm
by SharkysMachine
I'm totally wrong! I hooked up the new GCX. And it was the RS-10 -- basically sitting in factory reset. Glad it's not the gear but dreading the reprogramming job.

Lesson learned. I was so confident in the RS10 and so bummed by the though of having to reprogram it that I glossed it over.
But when the new one showed the same behavior I checked the channel - it had switched back to the default 15 and the CC# on the switches went back to default.

And my dead assessment was because I had not plugged the midi cable back in -- comedy of errors.

So hats off to bettsaj - you nailed it -- i feel like a dope - spent a month trying to figure it out. LOL
I put the first few hours in - just to get control of the the loops and 4 pre amp channels on bank 1.
Long road to hoe.