Finding a hum

BillESC

Well-Known Member
Back story.

Early in 2004 I installed a sound system in a 100 year old church. This included 8 EV recessed ceiling speakers and six wireless mics.

As time passed, we installed a sound system in the fellowship hall, teen center in the basement, etc.

Two years ago we replaced their 600 MHz wireless mics with Audio Technica ATW-1300 series systems.

Recently we received a service call to find a hum. Neal and I spent a total of 4 hours chasing down the problem.

Replacing cables, unplugging components, lifting grounds, removing power supplies, etc.

A Bogen tuner amplifier turned out to have a hum. It is shipping out for warranty repair since the Gold Series has a 3 year window.

Anyone else think Hums are hard?
 
I’ve chased my fair share of hums. It really depends how easy it is to physically bypass equipment or cabling to test for the problem segment.

Systems with complex DSPs where you can’t just plug in an XLR bypass and you have to start swapping Euro blocks and reprogramming at the same time to not run the wrong signal somewhere gets fun.

Sounds like you (kind of) had an advantage knowing the system too. As builts change. Settings change. This usually proves to be the hard part- figuring out where to look, especially in a system where you’re unfamiliar entirely.
 
Yes, hums can be very difficult to find, especially in systems where there are any un-balanced interconnections. In broadcast engineering, I have the luxury of banning all equipment with un-balanced or psuedo balanced inputs or outputs.

The sound re-enforcement world is getting better, because analog consoles with un-balanced insert patch points and outboard processors are less common. Patch panels in installed systems is mostly a thing of the past, too. Getting the grounding right with patch panels is not easy.

There was a time when finding anything but mic inputs balanced was rare. We have the late Neil Muncy to thank for preaching to the industry back in the late 1980s to not only adopt more balanced I/Os, but to fix "the pin 1 problem," as he named it. There was a lot of really awful crap being made back then, and it all hummed. It took careful engineering to build large systems free of hum. I don't miss those days.
 
Back story.

Early in 2004 I installed a sound system in a 100 year old church. This included 8 EV recessed ceiling speakers and six wireless mics.

As time passed, we installed a sound system in the fellowship hall, teen center in the basement, etc.

Two years ago we replaced their 600 MHz wireless mics with Audio Technica ATW-1300 series systems.

Recently we received a service call to find a hum. Neal and I spent a total of 4 hours chasing down the problem.

Replacing cables, unplugging components, lifting grounds, removing power supplies, etc.

A Bogen tuner amplifier turned out to have a hum. It is shipping out for warranty repair since the Gold Series has a 3 year window.

Anyone else think Hums are hard?
@BillESC Nah. . . Finding hums is/are EASY, it's eradicating and exorcizing them that's the tuffy.
Toodleoo!
Ron Hebbard
 
Yes, hums can be very difficult to find, especially in systems where there are any un-balanced interconnections. In broadcast engineering, I have the luxury of banning all equipment with un-balanced or psuedo balanced inputs or outputs.

The sound re-enforcement world is getting better, because analog consoles with un-balanced insert patch points and outboard processors are less common. Patch panels in installed systems is mostly a thing of the past, too. Getting the grounding right with patch panels is not easy.

There was a time when finding anything but mic inputs balanced was rare. We have the late Neil Muncy to thank for preaching to the industry back in the late 1980s to not only adopt more balanced I/Os, but to fix "the pin 1 problem," as he named it. There was a lot of really awful crap being made back then, and it all hummed. It took careful engineering to build large systems free of hum. I don't miss those days.
@FMEng I too don't miss those days but I sure do miss Mister Muncy.
In another lifetime, I donated an Imperial butt load of 1960's commercial broadcast studio gear to Mr. Muncy for a proposed broadcast museum and delivered it directly to his home north of Toronto. It was a hot summer afternoon and in return Mr. Muncy ( Neil, just call me Neil) invited me into his basement for freshly squeezed orange juice with the Australian fellow behind Surgex, they were sitting in Mr. Muncy's air conditioned basement rehearsing a presentation on surge suppression they later gave at an AES conference in New York then repeated for the Toronto chapter.
Thanks for the memories and
Toodleoo!
Ron Hebbard
 
Anyone else think Hums are hard?

They certainly can be. I haven't been doing this as long as some folks but I've seen my share. The one I remember as surprising me the most was a bad rack power distribution piece (similar to Furman PL-8). I was only surprised because it was a permanent install in a studio and theoretically nothing was moved around at all. Also once had a bad input XLR jack on a mains EQ (input cable must have got yanked) and I pulled the unit apart to resolder the PCB jack onto the board then everything was fine. The ones I like most, to be honest are when you can solve an issue by supplying different AC power - easy, fun, problem fixed and everyone happy (some may even be mildly impressed).
 
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Spelunking for hums is my favorite pastime. My favorite series of hums was at a university's roadhouse theater. They had gremlins in their PA system, intercom, and 70V systems. The PA was overhauled completely so whatever that problem was we addressed when all of the patchbays were replaced and the grounding and lifts were corrected. The intercom was on the fritz because the old cabling deteriorated in some of the wall stations and the foil shield came in contact with the conduit. The 70V was the best. Someone in the scene shop drilled into a CMU wall and tore a hole in a conduit with all the backstage 70V cabling in it. They turned it into a rat's nest and shorted everything out, walked away like nothing happened, and left it that way for several years until we traced out their entire 70v system to find the short.
 
They turned it into a rat's nest and shorted everything out, walked away like nothing happened, and left it that way for several years

I'm in the middle of a move and don't have all my photos readily available, but I have photos of stuff like this. It's comical, so I know the pain.
 
Spelunking for hums is my favorite pastime. My favorite series of hums was at a university's roadhouse theater. They had gremlins in their PA system, intercom, and 70V systems. The PA was overhauled completely so whatever that problem was we addressed when all of the patchbays were replaced and the grounding and lifts were corrected. The intercom was on the fritz because the old cabling deteriorated in some of the wall stations and the foil shield came in contact with the conduit. The 70V was the best. Someone in the scene shop drilled into a CMU wall and tore a hole in a conduit with all the backstage 70V cabling in it. They turned it into a rat's nest and shorted everything out, walked away like nothing happened, and left it that way for several years until we traced out their entire 70v system to find the short.
"Wasn't me, bossman, honest, I didn't see any sparks ..."
 
Indeed Humm Hunting and Destroying is quite the precarious occupation sometimes. As mentioned before, FINDING the hum can often be the easy part.
Good grasp of signal flow of course helps immensely, and when dealing with an unfamiliar system often you hope to god that you can find some good paperwork (if its a complicated system at least).
What's worse is when you find exactly what is causing the hum and there really isn't much of anything you can do to fix it (on budget). That is the worst.
 
Indeed Hum Hunting and Destroying is quite the precarious occupation sometimes. As mentioned before, FINDING the hum can often be the easy part.
Good grasp of signal flow of course helps immensely, and when dealing with an unfamiliar system often you hope to god that you can find some good paperwork (if its a complicated system at least).
What's worse is when you find exactly what is causing the hum and there really isn't much of anything you can do to fix it (on budget). That is the worst.
@Dionysus
How Freudian your last statement in light of where you're employed.
You've taken me back to New Years Eve December 31st 1982 / New Years Day January 1st 1983; the night / morning I first walked through your Grand's sound booth with Peter Roberts (within days of his vacating Stratford to follow Robin Phillips to the Grand as their new Production Manager), Dave (David P.) Long from your London, Ontario IA local was the gentleman who'd recorded and operated SFX while simultaneously mixing live reinforcement of the cast, chorus and pit orchestra of the Grand's Christmas / New Years musical.

Peter had borrowed me from Stratford for an overnight visit in search of a hum, a hum varying in intensity, frequency and harmonics with the optimistic goal of my finding, snaring, capturing and EXORCISING your Grand's hum; the hum they'd acquired less than a year before when they reopened after a full building upgrade: Heating, cooling, HVAC, make up air, electrical, water supply, drainage and venting, new lighting console, dimmers, hard-patch and load circuit distribution throughout.
Imagine your Board Of Directors' disappointment post their years of fundraising, corporate and private donations, total building remodeling only to be embarrassingly plagued by an OBVIOUS and ANNOYING mysterious combination of NEW hums they'd never had prior to their total upheaval and installation of all their wondrously marvelous, NEW and EXPENSIVE equipment and systems.

To move this along, here're my recollections of my 1st walk through New Years Eve, listed in point form in the order I noticed them:
- Walk in sound booth.
- 44 RU rack.
- Loaded 'helter skelter with an "interesting" variety of equipment.
- Four or five rows of decent quality, telco / broadcast style, long frame jacks.
- Patched with an eclectic assortment of standard 1/4" mono, stereo, shielded and non, instrument and SPEAKER cables.
- A 1/4" 1/4 track STEREO Revox A77 rack mounted immediately below the aforementioned four or five rows of telco jacks,
- Portions of the lower three rows of jacks BLOCKED by the two 10.5" reels when attempting to record or play tapes on the STEREO A77,
- A second portable, suitcase style, A77 sitting on a spent case of 24 of someone's preferred alcoholic beverage. This second Revox was borrowed from your studio venue in order to have a recorder / player capable of spinning 10.5" reels while still accessing the lower rows of the jack field.
- Layers and strips of every adhesive tape imaginable to route cables clear of the 5" reels fitted on the rack mounted Revox in order to have two machines available simultaneously.
- Both Revox's were 1/4", both were stereo BUT one was factory equipped with 2 track 1/2 track heads
while the other was fitted with 2 track 1/4 track heads.
Hmmm?? Why wouldn't you have two machines with identical head stacks to permit copying / dubbing from machine to machine?
- Read poorly labelled jack fields:
- Find jacks for channels 1 & 2 of the stereo 1/2 track Revox.
- Find jacks labelled for channels 1, 2, 3 and 4 of the STEREO 2 TRACK 1/4" 1/4 track rack mounted Revox.
Two problems:
1; Someone, (Read the consultant / system designer) thought one Revox was a four track simultaneous QUAD recorder player, it would rack mount in 6 RU and its 4 unbalanced inputs and 4 unbalanced outputs would interconnect wondrously via his rows of long frame , Telco style RTS jacks.
2; By reading the consultant's paper work, he was suggesting the installers should install the the "QUAD' recorder player in the main stage rack and he was including the portable STEREO recorder / player as a token loss leader for the future upgrade to your McManus Studio venue, the upgrade he was certain would be coming his way when everyone heard and saw his WONDROUS new installation in your Grands's main stage .
Apparently when someone realized neither Revox would mount in 6 RU, let alone BOTH of them, one of the Revox's was subbed from a rack mount to a portable.
- Notice mic level, line level, low impedance AND 70 volt speaker levels all being terminated and patched via the same telco style "tree blocks" within the rear of the rack enclosed by its hinged rear door, the door you can barely see, let alone OPEN, since it's backed solidly against the rear wall of the booth.
- The "tree blocks" were of course wired to their respective Telco style jacks via unshielded twisted pairs within an overall vinyl / PVC outer jacket.
- Four RADICALLY different signal levels tightly bound together in one overall outer jacket!
- Add intercom, a couple of 60 watt incandescent clip-on lights (also secured by the variety of ever popular adhesive back tapes) intertwine the clip ons unshielded 120 VAC power cables, add a home style 600 watt dual SCR dimmer to tame the two 60 watt clip ons down to performance level, season and adjust dimmer to "taste", and you wonder why it hums?

And then it got worse: How do all of the field terminations (mic level, line level, balanced, unbalanced, low impedance effects speakers, 70 volt paging, green room, crew and dressing room speakers intercom and 120 volt power circuits) route from their various distant locations to our "interesting" 44 RU rack?
Out the top of the rack, an assortment of 90 degree bends in conduit along with 90 degree turns in pull and junction boxes, across the booth ceiling to the windowed wall separating the booths from the attic ceiling, through the wall, another 90 degree turn via another assortment of bent conduit and pull boxes, onto Uni-Strut across the attic on the attic side of the booth wall to the SR / HL side wall of the attic.

Along the way, said Uni-Strut picked up a number of booth circuits carrying the outputs from Strand's Telco style lighting hard patch.

As the conduits on their Uni-Strut continued their journey towards the stage via the HL / SR wall of the attic, they were joined by ALL of the stage lighting circuits of the rear FOH lighting cove.
The ~36" length of Uni-Strut suspended from the attic ceiling via all-thread rods was now jammed end to end (side to side if you think of it that way) thus a second ~36" length of Uni-Strut was added below the first to accommodate ALL of the stage lighting circuits from the front FOH lighting cove.

Through the prosc' wall at attic level where additional stage lighting circuits were added for wall mounted stage lighting circuits in wall boxes away down there ~ 18" above stage level.
Continuing on their way to the USR corner of your building, our dutiful pair of Uni-Struts supported one immediately above one another were joined by ALL stage lighting circuits for the 1st LX, then the 2nd LX, then the 3rd LX then all of the wall mounted boxes across the US wall away down at ~18" above stage level.

And then it got even worse.

In the USR corner of your building ALL of the stage lighting circuits, 20 amp AND 50 amp stage lighting circuits, turned 90 degrees straight down into the top of Strand's telco style hard patch where every stage lighting circuit in your building's main stage patched into the outputs of 80 or a 100 SIX KW Strand dual SCR stage lighting dimmers in the dimmer room in the basement at trap level below your main stage's stage.
Sure, the previous consultant had specified all audio circuits would be installed in separate conduits segregated by signal level, and he was even willing to accept many of his different levels making 90 degree turns in one 2' x 2' pull box

BUT
He'd NEVER intended them to be ALL racked up together cheek by jowl on the same 36" length of Uni-Strut with a second length of similar Uni-Strut packed every bit as snuggly by every FOH stage lighting circuit in your main stage's FOH ceiling then through the prosc' and joined by every stage lighting circuit behind the prosc' wall before turning 90 degrees straight down, through Strands telco -style hard patch and then ALL the way down to below stage level.

And they wondered why it hummed.
And they wondered why the sound, pitch, intensity, level and harmonic content of the hum changed as a function of their lighting cues???

The better query'd be: How could they expect it NOT to HUMMM?
When I summarized my thoughts and your theatre's management called their consultant, his position was he'd specified separate conduit systems, pipes, pull and junction boxes; it was the electrical PEng and electrical contractor's faults for not maintaining their conduits and conduit systems well away from his audio conduits and systems.
I don't need to tell you where they felt the failure to communicate occurred.
I suspect @TimMc and others will NEVER have witnessed this sort of failure to communicate.
@Dionysus If you've ever noticed; this would explain the installation of ALL new conduit systems, conduits, pull and junction boxes along with bonus systems added to your studio space largely comprised of equipment removed from your main stage's system.

To pour a little more salt on their wounds:
Your entire London Ontario Grand complex closed and relocated to rented facilities for a full year in 1981 or 82 only to have more and worse HUMs than they'd ever had then have some nut case from Stratford walk through on New Year's Eve and tell them. Two things:
1; You've a collection of less than desirable gear. Nothing wrong with a TEAC Tascam model 3 but they were not known for their fabulous RF and electromagnetic noise rejection, or their Model 5. I beleive the Model 5 ended up in your space and the Model 3 became part of Sheila McCarthy's choreography and warm up little rolling rack housing the Model 3 facing up on top of a rolling rack containing two consumer grade cassette decks and either a butch stereo amp, or two butch mono amps in the bottom of the rack for ballast and stability while rolling and to power two JBL 4310's removed from some where in the upgrade from only one or two years earlier.
2; Interfaced in a totally incorrect / not feasibly corrected manner.
Net result: All new equipment interconnected by TOTALLY new conduits, boxes and cables.
Pretty much everything removed was handed down to your McManus Studio space and a portable / rolling system for the choreographer / warm up people.
Toodleoo!
Ron Hebbard
 
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wait!? you mean all those pallets of patch cords made of speaker cable leftovers I've been selling on the interweb are ... wrong? :)

What an incredible pile of cock-ups. I wish I had such a great memory as you, Ron, for disasters I've seen and either conquered or backed away slowly with my hands in the air ...
 
wait!? you mean all those pallets of patch cords made of speaker cable leftovers I've been selling on the interweb are ... wrong? :)

What an incredible pile of cock-ups. I wish I had such a great memory as you, Ron, for disasters I've seen and either conquered or backed away slowly with my hands in the air ...
@Ben Stiegler ALL experiences are, or can / ought to be, learning experiences: Some teach how to do, others how NOT to do.
Toodleoo!
Ron Hebbard
 
@Dionysus
How Freudian your last statement in light of where you're employed.
You've taken me back to New Years Eve December 31st 1982 / New Years Day January 1st 1983; the night / morning I first walked through your Grand's sound booth with Peter Roberts (within days of his vacating Stratford to follow Robin Phillips to the Grand as their new Production Manager), Dave (David P.) Long from your London, Ontario IA local was the gentleman who'd recorded and operated SFX while simultaneously mixing live reinforcement of the cast, chorus and pit orchestra of the Grand's Christmas / New Years musical.

Peter had borrowed me from Stratford for an overnight visit in search of a hum, a hum varying in intensity, frequency and harmonics with the optimistic goal of my finding, snaring, capturing and EXORCISING your Grand's hum; the hum they'd acquired less than a year before when they reopened after a full building upgrade: Heating, cooling, HVAC, make up air, electrical, water supply, drainage and venting, new lighting console, dimmers, hard-patch and load circuit distribution throughout.
Imagine your Board Of Directors' disappointment post their years of fundraising, corporate and private donations, total building remodeling only to be embarrassingly plagued by an OBVIOUS and ANNOYING mysterious combination of NEW hums they'd never had prior to their total upheaval and installation of all their wondrously marvelous, NEW and EXPENSIVE equipment and systems.

To move this along, here're my recollections of my 1st walk through New Years Eve, listed in point form in the order I noticed them:
- Walk in sound booth.
- 44 RU rack.
- Loaded 'helter skelter with an "interesting" variety of equipment.
- Four or five rows of decent quality, telco / broadcast style, long frame jacks.
- Patched with an eclectic assortment of standard 1/4" mono, stereo, shielded and non, instrument and SPEAKER cables.
- A 1/4" 1/4 track STEREO Revox A77 rack mounted immediately below the aforementioned four or five rows of telco jacks,
- Portions of the lower three rows of jacks BLOCKED by the two 10.5" reels when attempting to record or play tapes on the STEREO A77,
- A second portable, suitcase style, A77 sitting on a spent case of 24 of someone's preferred alcoholic beverage. This second Revox was borrowed from your studio venue in order to have a recorder / player capable of spinning 10.5" reels while still accessing the lower rows of the jack field.
- Layers and strips of every adhesive tape imaginable to route cables clear of the 5" reels fitted on the rack mounted Revox in order to have two machines available simultaneously.
- Both Revox's were 1/4", both were stereo BUT one was factory equipped with 2 track 1/2 track heads
while the other was fitted with 2 track 1/4 track heads.
Hmmm?? Why wouldn't you have two machines with identical head stacks to permit copying / dubbing from machine to machine?
- Read poorly labelled jack fields:
- Find jacks for channels 1 & 2 of the stereo 1/2 track Revox.
- Find jacks labelled for channels 1, 2, 3 and 4 of the STEREO 2 TRACK 1/4" 1/4 track rack mounted Revox.
Two problems:
1; Someone, (Read the consultant / system designer) thought one Revox was a four track simultaneous QUAD recorder player, it would rack mount in 6 RU and its 4 unbalanced inputs and 4 unbalanced outputs would interconnect wondrously via his rows of long frame , Telco style RTS jacks.
2; By reading the consultant's paper work, he was suggesting the installers should install the the "QUAD' recorder player in the main stage rack and he was including the portable STEREO recorder / player as a token loss leader for the future upgrade to your McManus Studio venue, the upgrade he was certain would be coming his way when everyone heard and saw his WONDROUS new installation in your Grands's main stage .
Apparently when someone realized neither Revox would mount in 6 RU, let alone BOTH of them, one of the Revox's was subbed from a rack mount to a portable.
- Notice mic level, line level, low impedance AND 70 volt speaker levels all being terminated and patched via the same telco style "tree blocks" within the rear of the rack enclosed by its hinged rear door, the door you can barely see, let alone OPEN, since it's backed solidly against the rear wall of the booth.
- The "tree blocks" were of course wired to their respective Telco style jacks via unshielded twisted pairs within an overall vinyl / PVC outer jacket.
- Four RADICALLY different signal levels tightly bound together in one overall outer jacket!
- Add intercom, a couple of 60 watt incandescent clip-on lights (also secured by the variety of ever popular adhesive back tapes) intertwine the clip ons unshielded 120 VAC power cables, add a home style 600 watt dual SCR dimmer to tame the two 60 watt clip ons down to performance level, season and adjust dimmer to "taste", and you wonder why it hums?

And then it got worse: How do all of the field terminations (mic level, line level, balanced, unbalanced, low impedance effects speakers, 70 volt paging, green room, crew and dressing room speakers intercom and 120 volt power circuits) route from their various distant locations to our "interesting" 44 RU rack?
Out the top of the rack, an assortment of 90 degree bends in conduit along with 90 degree turns in pull and junction boxes, across the booth ceiling to the windowed wall separating the booths from the attic ceiling, through the wall, another 90 degree turn via another assortment of bent conduit and pull boxes, onto Uni-Strut across the attic on the attic side of the booth wall to the SR / HL side wall of the attic.

Along the way, said Uni-Strut picked up a number of booth circuits carrying the outputs from Strand's Telco style lighting hard patch.

As the conduits on their Uni-Strut continued their journey towards the stage via the HL / SR wall of the attic, they were joined by ALL of the stage lighting circuits of the rear FOH lighting cove.
The ~36" length of Uni-Strut suspended from the attic ceiling via all-thread rods was now jammed end to end (side to side if you think of it that way) thus a second ~36" length of Uni-Strut was added below the first to accommodate ALL of the stage lighting circuits from the front FOH lighting cove.

Through the prosc' wall at attic level where additional stage lighting circuits were added for wall mounted stage lighting circuits in wall boxes away down there ~ 18" above stage level.
Continuing on their way to the USR corner of your building, our dutiful pair of Uni-Struts supported one immediately above one another were joined by ALL stage lighting circuits for the 1st LX, then the 2nd LX, then the 3rd LX then all of the wall mounted boxes across the US wall away down at ~18" above stage level.

And then it got even worse.

In the USR corner of your building ALL of the stage lighting circuits, 20 amp AND 50 amp stage lighting circuits, turned 90 degrees straight down into the top of Strand's telco style hard patch where every stage lighting circuit in your building's main stage patched into the outputs of 80 or a 100 SIX KW Strand dual SCR stage lighting dimmers in the dimmer room in the basement at trap level below your main stage's stage.
Sure, the previous consultant had specified all audio circuits would be installed in separate conduits segregated by signal level, and he was even willing to accept many of his different levels making 90 degree turns in one 2' x 2' pull box

BUT
He'd NEVER intended them to be ALL racked up together cheek by jowl on the same 36" length of Uni-Strut with a second length of similar Uni-Strut packed every bit as snuggly by every FOH stage lighting circuit in your main stage's FOH ceiling then through the prosc' and joined by every stage lighting circuit behind the prosc' wall before turning 90 degrees straight down, through Strands telco -style hard patch and then ALL the way down to below stage level.

And they wondered why it hummed.
And they wondered why the sound, pitch, intensity, level and harmonic content of the hum changed as a function of their lighting cues???

The better query'd be: How could they expect it NOT to HUMMM?
When I summarized my thoughts and your theatre's management called their consultant, his position was he'd specified separate conduit systems, pipes, pull and junction boxes; it was the electrical PEng and electrical contractor's faults for not maintaining their conduits and conduit systems well away from his audio conduits and systems.
I don't need to tell you where they felt the failure to communicate occurred.
I suspect @TimMc and others will NEVER have witnessed this sort of failure to communicate.
@Dionysus If you've ever noticed; this would explain the installation of ALL new conduit systems, conduits, pull and junction boxes along with bonus systems added to your studio space largely comprised of equipment removed from your main stage's system.

To pour a little more salt on their wounds:
Your entire London Ontario Grand complex closed and relocated to rented facilities for a full year in 1981 or 82 only to have more and worse HUMs than they'd ever had then have some nut case from Stratford walk through on New Year's Eve and tell them. Two things:
1; You've a collection of less than desirable gear. Nothing wrong with a TEAC Tascam model 3 but they were not known for their fabulous RF and electromagnetic noise rejection, or their Model 5. I beleive the Model 5 ended up in your space and the Model 3 became part of Sheila McCarthy's choreography and warm up little rolling rack housing the Model 3 facing up on top of a rolling rack containing two consumer grade cassette decks and either a butch stereo amp, or two butch mono amps in the bottom of the rack for ballast and stability while rolling and to power two JBL 4310's removed from some where in the upgrade from only one or two years earlier.
2; Interfaced in a totally incorrect / not feasibly corrected manner.
Net result: All new equipment interconnected by TOTALLY new conduits, boxes and cables.
Pretty much everything removed was handed down to your McManus Studio space and a portable / rolling system for the choreographer / warm up people.
Toodleoo!
Ron Hebbard
OH MY, this explains SO MUCH... I'd love to sit down with you and our former-TD (now "project manager" in charge of our close upcoming NEW GIANT RENOVATION that happens this summer) with a bowl of popcorn, audio recorder and a notepad.
I ripped most of the stuff that was installed in the McManus Studio (Now McManus Stage, and after this summer Auburn Stage) during my time here. The Patch pannel is gone, dimmers replaced, I cut apart the rack to more easily get it out of the booth (geez the door is narrow) and replaced it. I'd be happy to send you photos of the booth as it is... It will of course be different again once the summer reno. I bought the soundcraft console when they got rid of it (sold it myself two years later). I still have the Warfdale Pro speakers at home.

Speaking of hums, there was a nasty hum in the clearcom that got worse. When gutting the rack and deciding what might be worth keeping I had a wooden plank with a Stand transformer on it smack me in the head. A collection of caps, resistors and such zip-tied on to the wires to keep things "tidy". Turns out that was the clearcom power suppy I could not find in order to diagnose the hum. PROBLEM SOLVED, got the then TD to replace the clearcom power. When I initially asked I got quite some resistance. I then showed him a photo of it... Was told to throw it out :).
 
OH MY, this explains SO MUCH... I'd love to sit down with you and our former-TD (now "project manager" in charge of our close upcoming NEW GIANT RENOVATION that happens this summer) with a bowl of popcorn, audio recorder and a notepad.
I ripped most of the stuff that was installed in the McManus Studio (Now McManus Stage, and after this summer Auburn Stage) during my time here. The Patch pannel is gone, dimmers replaced, I cut apart the rack to more easily get it out of the booth (geez the door is narrow) and replaced it. I'd be happy to send you photos of the booth as it is... It will of course be different again once the summer reno. I bought the soundcraft console when they got rid of it (sold it myself two years later). I still have the Warfdale Pro speakers at home.

Speaking of hums, there was a nasty hum in the clearcom that got worse. When gutting the rack and deciding what might be worth keeping I had a wooden plank with a Stand transformer on it smack me in the head. A collection of caps, resistors and such zip-tied on to the wires to keep things "tidy". Turns out that was the clearcom power suppy I could not find in order to diagnose the hum. PROBLEM SOLVED, got the then TD to replace the clearcom power. When I initially asked I got quite some resistance. I then showed him a photo of it... Was told to throw it out :).
In the renovation I took on under Peter Roberts reign, we had included a percentage of Clear-Com RS105 belt packs and Beyer DT108 headsets as spares for the new main stage 'Hum busting' upgrades.
Your Executive Board of Directors, folks like the Iveys and Canada Trust, were simultaneously urinated (pissed) they'd been bamboozled, realized they spend more in legal fees than it was worth and figured since they were now bankrolling their second audio upgrades in two years, once they heard every thing Dave Long and I were doing to save their bacon was 125% value for dollars spent; once Dave and I had them eating out of palms, we just kept right on rolling: With only two weeks time and XX more dollars we could improve this and this. Asked, answered. and moving right along.
With only one more week and X more dollars we could also do this while we're here.
When the bottom fell out of your Board of Directors' pipe dream (the dream in which they were SURE all it would take to turn their Grand Theatre into their even grander vision of a repertory operation to put Stratford's to shame) one of the few things Dave Long and I had left on our 'bucket list' was to build a new Clear-Com power supply clone like the pair I built while working as Stratford's Head of Sound in their main stage; the same pair of supplies running the Players' Guild of Hamilton's and Burlington's Little Theatre Clear-Com systems to this very day.
When I built them in 1978 their parts cost less than 30% of the wholesale cost of ONE genuine, single channel, Clear-Com supply.
The abortion that hit you on your head was pasted together from an old DC supply abandoned by @Ron Foley while he was installing your main stage's snazzy new LX board: A British MMS (Modular Memory System) possibly although I may have the exact model incorrect.
Control Booth's Bat Call may summon @Ron Foley and he'll likely still recall your little relic.
Gotta go.
Toodleoo!
Ron Hebbard
 
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I just recorded a show in a 700 seat space, following a $60 Million renovation. The venue crew told me a bunch of things were still wrong, and every week the well known, local integrator would come back and make changes without telling them what was done. Every show is a new adventure.

I observed that their pre-show music iPad was bleeding slightly into my console. The crosstalk was possibly due to it running unbalanced through a patch panel that also carried some tie lines I was using. Audio fed into a ground buss is not a good idea. I suggested putting a transformer on it. It apparently stymies the integrator.

I mentioned to the house audio gal that it seemed odd that her stage digital I/O box was placed in a logical, discrete position, right next to a power receptacle and a fancy, engraved audio tie line panel, yet she had to run the network cable for it some 25 feet away to a very visible wall panel. She rolled her eyes and said it made no sense, like a number of things the designers did. Apparently, the designers hadn't actually worked on a stage in too long, and nobody asked the crew to review the plans.
 
Probably my most memorable hum occurred on tour some years ago. I was a lighting system tech at the time. We were in a shed when we were hit with a pretty significant thunderstorm as doors were opening. It got so bad that we powered everything down during the storm, and we powered back up once the storm passed. As we were getting things going again, we discovered that a nasty buzz had mysteriously developed in our Clear-Com system. We also were experiencing some strange DMX issues as well.

We were not able to find the issue before the show after troubleshooting, and made it through with the annoying him in the com and some occasional glitches in early generation LED tubes we were carrying. The thought was that perhaps the snake had been damaged, and the next day we inspected it but found no obvious trauma. We survived show 2 with this gremlin not without the cursing of the LD over the issues. We did now know that the issues began once FOH was set up with com and DMX running through the snake.

Since I was the one taking the heat from the LD, I needed to get to the bottom of it. I first methodically began to unplug things from the stage end of the snake trying to isolate the source of the problem only to discover that the problem was pretty much global in the snake. I again inspected every inch of the 300’ snake and again found no issues. As I made my way to FOH, I once again methodically unplugged things to find that the biz went away when I unplugged the DMX lines from the snake, which was interesting. After replugging the DMX back in the buzz returned, but finally went away after unplugging the external monitors of the lighting console. The culprit- a damaged power supply for one of the external monitors that was sending voltage through the video connection to the console which made it through the chassis of the desk through the DMX connectors and then through the common ground of the snake.

I again saw these symptoms again on another tour the following year. I skipped everything and went right for the external console monitors, which to the LD and the Audio guys made it appear that I was out of my mind, but they were amazed to find that it was indeed the monitor PSU that was causing the hum....
 
Probably my most memorable hum occurred on tour some years ago. I was a lighting system tech at the time. We were in a shed when we were hit with a pretty significant thunderstorm as doors were opening. It got so bad that we powered everything down during the storm, and we powered back up once the storm passed. As we were getting things going again, we discovered that a nasty buzz had mysteriously developed in our Clear-Com system. We also were experiencing some strange DMX issues as well.

We were not able to find the issue before the show after troubleshooting, and made it through with the annoying him in the com and some occasional glitches in early generation LED tubes we were carrying. The thought was that perhaps the snake had been damaged, and the next day we inspected it but found no obvious trauma. We survived show 2 with this gremlin not without the cursing of the LD over the issues. We did now know that the issues began once FOH was set up with com and DMX running through the snake.

Since I was the one taking the heat from the LD, I needed to get to the bottom of it. I first methodically began to unplug things from the stage end of the snake trying to isolate the source of the problem only to discover that the problem was pretty much global in the snake. I again inspected every inch of the 300’ snake and again found no issues. As I made my way to FOH, I once again methodically unplugged things to find that the biz went away when I unplugged the DMX lines from the snake, which was interesting. After replugging the DMX back in the buzz returned, but finally went away after unplugging the external monitors of the lighting console. The culprit- a damaged power supply for one of the external monitors that was sending voltage through the video connection to the console which made it through the chassis of the desk through the DMX connectors and then through the common ground of the snake.

I again saw these symptoms again on another tour the following year. I skipped everything and went right for the external console monitors, which to the LD and the Audio guys made it appear that I was out of my mind, but they were amazed to find that it was indeed the monitor PSU that was causing the hum....
DMX on an audio snake ... not recommended as DMX pulses need much lower capacitance cable to keep the pulse edges sharp than is used for audio grade mic cable ...
 

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