ClearCom Beltpack Compatibility

[Les]

I know we have discussed this many times before, but I just want to make sure before I encourage my venue to spend any money.

We have a ClearCom system, circa 1995. We use RS-501 beltpacks, and I'm in a position where I could use a few more (at minimum). Unfortunately, there is no budget for this (is there ever?) and even the old, crusty 501's are between $100-150 on eBay.

But I found some old-stock RS-100's that really intrigue me (and the price is a little better). I could use those for our followspot loft and free up some 501's for other uses. I've read here that the RS-100 is compatible with Series 500 systems, but I guess I just kinda want to hear it again.

While we are at it, any other recommendations for compatible beltpacks?

PPS: I have one RS-501 that is totally dead, but no obvious signs of internal failure. Is there anything common I should be looking for?

 

[themuzicman]

Yep, super compatible. I've said it before, RS-100A's are my go-to for my orchestra pits because of the physical latch on/off switch. They won't sound as nice as the newer series stuff, but they are rock-solid.

 

[Amiers]

PPS Reply: pictures.

 

[derekleffew]

Google image takes me to this thread: https://www.controlbooth.com/threads/clearcom-problem.27608/#post-245443 , which indicates that RS-100, RS-501, as well as RS-601, are ALL compatible with each other.

 

[Les]

Thanks all for the advice.

I know that we have two Clearcom threads going on here, so mods feel free to merge them if you wish.

With that being said, I think I've decided to go in a new direction:

To start off, this is a two-channel system, but we seem to treat A and B alike. It doesn't seem to matter which one you plug in to.
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

There are two locations in my venue that currently use beltpacks that would really be better off with a wall or desktop station. One is stage right on the proscenium wall, and the other is in the tech booth - where we often have an SM between the lighting and sound consoles. In both these locations, beltpacks are often drug around, knocked to the floor, taped to things, etc. We already have three permanent stations — KB111A's at the Stage Manager's console (SL), Lighting Console, and Sound Console.

So I found a few people selling KB111A's online, one of which is an older-looking unit (brown instead of beige) mounted in a desktop console. That would be great for the SM's spot in the booth, and an additional wall panel could be mounted SR. Two-gang boxes with one 3-pin XLR connector per channel already exist in both these locations.

Compatibility doesn't seem to be an issue, but I want to make sure our PSU can handle it. We already use beltpacks there, so I wouldn't imagine this would be much different (and we don't use the speakers).

I also noticed that the console version has an I/O with 4-pin XLR (male and female). I'm assuming that since I have six wires in these wall boxes, I would end up with shield, A+, A-; B+, B-. I know that the KB111A has a 5-way terminal strip on the rear. My plan would be to replace the XLR's with a single 4-pin female and either have a patch cord leading to the tabletop station and a wire in the wall feeding the built-in station.

Now I haven't looking in to any of the pinouts, installation manuals, or circuit diagrams and will certainly seek clarification before starting. I'm just wanting to make sure this scheme is even possible before going any further.

Here are some pics I took around the venue tonight:

Typical beltpack location:

KB111A. The black bezel has speaker controls, etc. Would this be necessary when adding additional panels?

PSU (Front)

PSU (Rear-Left)

PSU (Rear-Right)

@RonHebbard , @themuzicman - you guys seem to know a lot about this stuff. Am I on the right track or at least getting close?

 

[derekleffew]

To start off, this is a two-channel system, but we seem to treat A and B alike. It doesn't seem to matter which one you plug in to.

That's because both channels are linked on the power supply. Bottom right of photo#3 above. Set Link to OFF and A and B will be as if two separate systems.

I also noticed that the console version has an I/O with 4-pin XLR (male and female). I'm assuming that since I have six wires in these wall boxes, I would end up with shield, A+, A-; B+, B-. I know that the KB111A has a 5-way terminal strip on the rear. My plan would be to replace the XLR's with a single 4-pin female and either have a patch cord leading to the tabletop station and a wire in the wall feeding the built-in station.

To my knowledge, CC has never used 4pin XLR for anything other than headset. Two channel are either 5pin or 6pin.

 

[Les]

That's because both channels are linked on the power supply. Bottom right of photo#3 above. Set Link to OFF and A and B will be as if two separate systems.

Thank you for that! Might do some testing/asking around to see if SM's would prefer backstage to be separated from FOH. Though I suspect they might prefer the simplicity of the Linked system.

To my knowledge, CC has never used 4pin XLR for anything other than headset. Two channel are either 5pin or 6pin.

That's the belief I've always held, at least relating to 4-pin = headsets. Here's the pictures that are throwing me for a loop:







I wonder what gives?

...And going further down the rabbit hole, here's a newer KB111A with 3-pin:

 

[RonHebbard]

Thanks all for the advice.

I know that we have two Clearcom threads going on here, so mods feel free to merge them if you wish.

With that being said, I think I've decided to go in a new direction:

To start off, this is a two-channel system, but we seem to treat A and B alike. It doesn't seem to matter which one you plug in to.
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––

There are two locations in my venue that currently use beltpacks that would really be better off with a wall or desktop station. One is stage right on the proscenium wall, and the other is in the tech booth - where we often have an SM between the lighting and sound consoles. In both these locations, beltpacks are often drug around, knocked to the floor, taped to things, etc. We already have three permanent stations — KB111A's at the Stage Manager's console (SL), Lighting Console, and Sound Console.

So I found a few people selling KB111A's online, one of which is an older-looking unit (brown instead of beige) mounted in a desktop console. That would be great for the SM's spot in the booth, and an additional wall panel could be mounted SR. Two-gang boxes with one 3-pin XLR connector per channel already exist in both these locations.

Compatibility doesn't seem to be an issue, but I want to make sure our PSU can handle it. We already use beltpacks there, so I wouldn't imagine this would be much different (and we don't use the speakers).

I also noticed that the console version has an I/O with 4-pin XLR (male and female). I'm assuming that since I have six wires in these wall boxes, I would end up with shield, A+, A-; B+, B-. I know that the KB111A has a 5-way terminal strip on the rear. My plan would be to replace the XLR's with a single 4-pin female and either have a patch cord leading to the tabletop station and a wire in the wall feeding the built-in station.

Now I haven't looking in to any of the pinouts, installation manuals, or circuit diagrams and will certainly seek clarification before starting. I'm just wanting to make sure this scheme is even possible before going any further.

Here are some pics I took around the venue tonight:

Typical beltpack location:
View attachment 15563

KB111A. The black bezel has speaker controls, etc. Would this be necessary when adding additional panels?
View attachment 15559

PSU (Front)
View attachment 15562

PSU (Rear-Left)
View attachment 15561

PSU (Rear-Right)
View attachment 15560

@RonHebbard , @themuzicman - you guys seem to know a lot about this stuff. Am I on the right track or at least getting close?

@Les Several comments / queries:
When your system is complete with all belt packs and speaker stations connected, how many of each will you have / how many in total across all channels?
The manual supplied with your base station / power supply should give you the maximum number of units it's designed to power.
If you find yourself exceeding the power supply's capability, you don't need to replace, merely add an additional bare-bones, supply in parallel. Of course you can connect this additional supply anywhere on the system. There's no requirement for it to be adjacent to the first supply. The two supplies don't need to be identical in the sense if your original supply is part of a base station, as yours is, your second supply could be a second identical unit or could merely be a stand-alone ClearCom rack mount power supply. Of course you could also build an additional raw power supply.
Good rules to live by:
Only have one ground on your system and have that at your power supply. If you have both supplies adjacent to each other, you MAY get away with grounding both without experiencing ground loop hum. If your two supplies are on opposite sides of an arena, you may need to float the ground on one of the supplies to avoid ground loop hum. Remember ClearCom's old style party lines are single-sided / unbalanced systems.
NEVER connect any #1 contacts and / or shields to ground. Use heat-shrink and / or Teflon sleeving to keep all shields insulated from ground.
Enable only one termination per channel and each channel requires its own termination.
Be careful when using multiple base station / power supplies to NOT double terminate any one channel.
Watch the sequence of the hard-wiring connection points on all two channel, hard-wired stations. I can't recall a specific model number but one of the small, 2 gang, wall stations has some of it's terminals in an order that my catch you napping. They're clearly and correctly labelled but perhaps not quite in what you'd think a logical sequence.
My eyesight is extremely poor but I thought I noticed you running your base station with the A & B channels coupled together creating, effectively, a single channel system. No problem, none whatsoever so long as you're aware of it.
I was unable to see / read the additional connections and controls on the black bezel of the station you asked about and thus am not commenting.
Questions about old style ClearCom party line gear, bring em' on. New digital stations, ask another poster.
Toodleoo!
Ron Hebbard.

 

[MNicolai]

Rather than replace the dual XLR3 connectors, I would create a dual XLR3 cable that straps onto the terminal strip of the KB unit. The wiring diagram is accurate. Each of the 3-pin cables busses together on the +30V and Ground, and then Ch A and Ch B land on discrete terminals.

The addition of the speaker station shouldn't load down your PSU too much. Really depends on how many beltpacks you're pushing on top of it though.

The portable box is actually supposed to be an XLR3 and only supports one channel down the cable. My suspicion is someone modded that unit to an XLR4 to make it a 2ch unit down the cable so the A/B switch functions as expected.

 

[RonHebbard]

Thank you for that! Might do some testing/asking around to see if SM's would prefer backstage to be separated from FOH. Though I suspect they might prefer the simplicity of the Linked system.



That's the belief I've always held, at least relating to 4-pin = headsets. Here's the pictures that are throwing me for a loop:

View attachment 15567

View attachment 15566

View attachment 15565

I wonder what gives?

...And going further down the rabbit hole, here's a newer KB111A with 3-pin:
View attachment 15568

View attachment 15569

@Les @derekleffew Here's my recollection. When ClearCom offered the stylish little wooden back-box, they only offered it with XLR-3 males and females intended for use with single channel installations. When mounting dual channel stations, I've done it a couple of ways. If the system only has two channels in total, I've swapped ClearCom's original pair of XLR-3s for anything up to XLR-7's and CLEARLY LABELLED them depending upon the needs of the system. I believe, they also offered wall stations with four channel selector switches and I've retro-fitted the wooden desk-top housings to accommodate all manners of multi-pins and / or dual rows of male and female XLR-3s, basically whatever it took to suite the needs of the installation. Being a reputable installer, my partners and I provided multiple copies of ALL documentation. Queries? Keep 'em coming.
Toodleoo!
Ron Hebbard.

 

[Les]

@RonHebbard
We currently have three speaker stations (KB111A):
• Sound
• Lighting
• Stage Manager Console (Located SL)

And the following headset stations (* marks in-use; ** marks seldom-use)
• Followspot 1*
• Followspot 2*
• ASM SR* (to become speaker station)
• Booth Center* (to become desktop speaker station)
• SL Rear Wall**
• SR Rear Wall**
• Gallery 1**
• Gallery 2**
• House Left Catwalk**
• House Right Catwalk**
• Dimmer Room**

We usually run the three base stations and about 4 beltpacks (sometimes 5). After the upgrade, I would intend to run 5 base stations and a reasonable max of 2-3 beltpacks. I will see if I can find the manual for our PSU. I do think we can possibly scrape by since we rarely use most of our beltpack stations, and never all for one show. Heck, last time I checked, we only had 4 or 5 working beltpacks on the premises and it's likely to stay that way.

The buttons on the bezel are labeled as follows. For the record, we never use these:

Top two (amber)
• Page Stage
• Page Backstage
*These light up when the Audience Recall Chime is sounded. I assume they also sound the chime but to be honest I don't think I've tried.

Middle (Clear)
• Headset
• Mic/Spkr

Bottom (XLR)
• Microphone

 

[RonHebbard]

@RonHebbard
We currently have three speaker stations (KB111A):
• Sound
• Lighting
• Stage Manager Console (Located SL)

And the following headset stations (* marks in-use; ** marks seldom-use)
• ASM SR* (to become speaker station)
• Booth Center* (to become desktop speaker station)
• SL Rear Wall**
• SR Rear Wall**
• Gallery 1**
• Gallery 2**
• House Left Catwalk**
• House Right Catwalk**
• Dimmer Room**

We usually run the three base stations and about 4 beltpacks (sometimes 5). After the upgrade, I would intend to run 5 base stations and a reasonable max of 2-3 beltpacks. I will see if I can find the manual for our PSU. I do think we can possibly scrape by since we rarely use most of our beltpack stations, and never all at one time.

The buttons on the bezel are labeled as follows. For the record, we never use these:

Top two (amber)
• Page Stage
• Page Backstage
*These light up when the Audience Recall Chime is sounded. I assume they also sound the chime but to be honest I don't think I've tried.

Middle (Clear)
• Headset
• Mic/Spkr

Bottom (XLR)
• Microphone

@Les Beware the unbalanced ClearCom in your dimmer room will likely pick up dimmer / SCR noise big time: In general due to it being unbalanced and even more so whenever its mic is enabled. In my early days in the Stratford Festival's main stage dimmer room, they had a telco operator style weighted single conductor cable style hard patch for their then 100 dimmers. Occasionally it was necessary for an electrician to be on comms to execute hard re-patches between specific lighting cues. This resulted in horrible hum pick-up which was even worse when he enabled his mic to acknowledge. The solution was an ugly, but extremely effective, modification to a Beyer DT-109 headset. A replacement dynamic mic element was wired in series aiding, but mounted externally on the rear side of the originally supplied mic and its boom. Note the two elements were connected in series aiding rather than opposing but since they were physically mounted back to back, any hum picked up by one was picked up by the other 180 degrees out of polarity thus cancelling the majority of the hum picked up. It looked hideous, but the headset never left the dimmer room and served its purpose well.
Not a hum reducing method you employ very often but I've always remembered how well it worked in case I'm ever in need of it again.
Toodleoo
Ron Hebbard.

 

[Les]

Interesting note about the dimmer room Com. That location has never been used to my knowledge, and is just a pair of 3-pin XLR labeled "Intercom", much like the beltpack station pictured above. I have never had the need to put a beltpack in there. That being said, while it has been a hot minute since I was last on headset during a show, I remember hearing the slight buzz of the com change as lighting cues faded in and out. I wonder if that could be the culprit. It has never been pronounced enough to bother anyone, but I might look in to it anyway.

 

[RonHebbard]

I know we have discussed this many times before, but I just want to make sure before I encourage my venue to spend any money.

We have a ClearCom system, circa 1995. We use RS-501 beltpacks, and I'm in a position where I could use a few more (at minimum). Unfortunately, there is no budget for this (is there ever?) and even the old, crusty 501's are between $100-150 on eBay.

But I found some old-stock RS-100's that really intrigue me (and the price is a little better). I could use those for our followspot loft and free up some 501's for other uses. I've read here that the RS-100 is compatible with Series 500 systems, but I guess I just kinda want to hear it again.

While we are at it, any other recommendations for compatible beltpacks?

PPS: I have one RS-501 that is totally dead, but no obvious signs of internal failure. Is there anything common I should be looking for?

Interesting note about the dimmer room Com. That location has never been used to my knowledge, and is just a pair of 3-pin XLR labeled "Intercom", much like the beltpack station pictured above. I have never had the need to put a beltpack in there. That being said, while it has been a hot minute since I was last on headset during a show, I remember hearing the slight buzz of the com change as lighting cues faded in and out. I wonder if that could be the culprit. It has never been pronounced enough to bother anyone, but I might look in to it anyway.

@Les Two more comments for you.
1; Your ClearCom wiring in your dimmer room is possibly your culprit but you won't be able to do much about it short of removing it from the system / getting it away from the dimmer environment. You CAN'T simply short it to ground to minimize hum pick-up as this would take down your entire channel and / or the entire system depending upon whether you were shorting the audio line, the power line, or both. This is likely more trouble than it's worth if the amount of noise pick-up is inoffensive to users.
2; One of our local amateur groups has your exact two channel base station. When we got rid of the rats nest of shoddy damaged mic cables and I installed 1/2" EMT, back-boxes and cover plates with parallel pairs of XLR-3 males in all foreseeable locations and then some, I opted to install a 2 gang back box and 2 channel wall station in the FOH coat-check area for the convenience of house managers. In the past, headset cables had been strung out to FOH and a belt pack and headset provided whenever necessary to coordinate late comers entrances but this ALWAYS caused a couple of problems:
1; Amateurs being what they are, there was always never ending headset banter with various folks chattering away often being EXTREMELY critical of the performances of their peers leading to too many hurt feelings and damaged relationships not to mention the number of times folks unfamiliar with the belt-packs felt they needed to turn their mic on in order to hear then they'd chew gum and cough and gag then casually toss their headset on the coat-check counter and leave it switched on upon their departure.
When I installed the conduit and cleaned up all of the wiring, the group purchased a black HS-6 PTT (Push To Talk) handset and a wall mount for the convenience of whichever member was playing FOH manager on any given evening. As the group already owned the identical dual channel base station as yours, I wired the FOH wall station as channel 'B' and ALL other locations as channel 'A'. The stage manager, who was seated in front of the base station, was the only person who ever needed to communicate with the FOH manager and all was working well. I rolled in one evening to be greeted by a lower level minion who FRANTICALLY rushed up to me to inform me the headset system was broken. Why or how she'd ever know was a mystery as this person was a props and costume pixie with zero need to use the headsets EVER but she was jabbering away about how fortunate of her to discover this "before the SM arrived" only to find his headset system not working. I played the game and checked everything only to find EVERYTHING working to perfection.
The bottom line: The eager beaver / early arrival had tried to speak to her associate back stage from the FOH location WITHOUT realizing they were on two separate channels and thus never intended to speak to each other. Thereafter the system was employed either as two channels by knowledgeable SM's when desired or was left in 'A + B' combined / single channel mode when desired.
Toodleoo!
Ron Hebbard.

 

[Les]

@RonHebbard Hah! Thanks for the anecdote. I could almost see that happening at my venue. Luckily we only use our coat check closet for storage, and it doesn't have com! I have also heard stories - usually originating in high schools - pertaining to com stations located in dressing rooms. In particular, it was a dance performance presented by the cheerleaders and drill team which was teched by the theatre students. A certain technician learned the hard way that those stations have a speaker that can be listened in on, and maybe commenting over headset about how well-endowed a dancer is may not be such a good idea. This was the year before I attended the school and I remember running these performances - only now, the sponsor acted as SM and was on headset the entire time. I'm sure that was no accident. I do remember overhearing the girls talking about how they enjoyed the headset chatter; and that it was like some kind of strange radio show.

Well, it sounds like I can confidently recommend that the management buy a few of these stations. Then I can put two beltpacks at the followspot locations and hide the rest for when we put the occasional technician in random places throughout the venue (or when the director/orch conductor wants a headset during tech, God forbid).

I'm sure I will have more questions as I move forward, as I only partially understand the termination and grounding requirements (don't worry - I won't guess).
---
While I'm here, I had asked about a DOA beltpack in my first post. I brought it home with me and have looked it over in the light and still see nothing obviously wrong with it. Any ideas? @Amiers - did you want pictures?

 

[Amiers]

Yes please.

 

[Les]

Here ya go, @Amiers

















I don't see anything funky going on with the PCB. I guess it could be something really simple like one of the XLR connectors. The solder joints and the pins look fine so I'm not sure if there's any way they can fail other than that.