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Hey Gang! Sorry about the bump.

If you need my details on my build etc. please see my thread here on ROG titled Small Studio Build Journey or ask here and I'll give more.

For those of you both pro and not pro, in your experiences, some quick questions (I think anyway) on the items below please:

A.What are the Above Finished Floor wall heights of your boxes in the tracking spaces for:
1. AC Dirty Power?
2. AC clean power?
3. Wall plates for connectors (XLR, 1/4", CAT V etc.)?

B. Roughly, how many of each?

C. What is the linear spacing between them?

D. Would you do any of this differently now?

All of a sudden after over a year, the electrician calls and is ready fri AM . and for the first time. I'm not! Damn!
Thanks ever so much!

Comments

paulears Thu, 03/05/2015 - 14:29

I always install the final inside lining horizontally not vertical, so have a joint line at 4'. I cover this with a 4x1" pine strip, and then duplicate this strip lower down just enough to get a UK sized single or double ac outlet in the gap. Looks smart, and finishes well. In the UK we tend to use ring mains, rather than spurs, so in , my edit suit, which is 8 x 10' - I have double power outlets every 18", and it's still not enough. Lower down, at 12" above the floor, I have more doubles, but just a few so I can then drop 4 way mains outlets from them to power the power supplies. My audio and video cables don't go to wall sockets they terminate in 19" panels in freestanding racks, with plenty of slack so the racks can be rearranged.

vibrations1951 Thu, 03/05/2015 - 15:09

Thanks Paul. I will have a wide, what I call a chair strip at about 4' above the finished floor that should work well for mounting my AC boxes. Then the finish below consists of verticle slats that are 4", 6" and 8" wide with 1 1/2" slots between them. This should provide a decent mounting surface for Connector panels at about 2' AFF.

This is the way I'm thinking of going right now. I'm bringing in the AC from above. I'm just a bit hesitant about keeping my clean AC wiring coming in from the Equitech too close to the dirty AC for lights, vacuum or potential fans. My understanding is that they need to be at least 1' apart and preferably 2'. My LV comes up through chases in the slabs into the wall stud spaces so shouldn't be a problem.

I can see where your needs require lots of flexibility and options. Thanks again for the input.

vibrations1951 Thu, 03/05/2015 - 15:14

@Dave dog,@DVD,@Donny,kmetal
All of a sudden after over a year, the electrician calls and is ready fri AM ......and for the first time....I'm not!!! Damn!!!
I could use some quick info if possible. Anything at all would be appreciated. I have nothing to compare to.

A.What are the Above Finished Floor wall heights of your boxes in the tracking spaces for:
1. AC Dirty Power?
2. AC clean power?
3. Wall plates for connectors (XLR, 1/4", CAT V etc.)?

B. Roughly, how many of each?

C. What is the linear spacing between them?

D. Would you do any of this differently now?

Thanks ever so much!

dvdhawk Thu, 03/05/2015 - 16:09

Your electrician will install the receptacles at the normal height. If there's a standard that must be met to pass inspection, he'll know what that is. Going from memory I don't think electrical code dictates a specific height, so if you want something higher or lower for any reason (countertops, workbenches, etc.) you'll have to specify.

Master electrician Davedog will probably know what varies state to state. Here (and maybe everywhere in the US, I don't know), for your high-voltage, in inhabited areas of the building, spacing is a maximum of 12ft apart, with exclusions around doorways and walls under a certain width - such as you would have between a door and a corner. I'll see if I can find the pdf I have when I get home.

Low-voltage should be entirely at your discretion. I plan on keeping mine at the same standard receptacle height, except in places I anticipate mounting a flatscreen. Wherever I can, I will have the high-voltage and low-voltage boxes equally spaced, to keep the audio as far apart as possible from the electric.

Rod highly recommends routing your high-voltage high, and your low-voltage low wherever possible.

Have you compiled any kind of list that includes how much amperage / wattage all of your known devices draw? That should have figured into your HVAC calculations too.

Honestly, you should be able to track just about anything with one clean 20-amp circuit, so double / triple / quadruple that number of 20-amp circuits - to whatever margin of error / headroom you would like to have, or can afford. Homeruns back to the panel for each circuit will tally up when you get the bill. Personally, I don't plan on going overboard with "dirty" power. Those too will have to run to all the way back to a separate box.

All I can say right now. I'll check back in when I get home.

vibrations1951 Thu, 03/05/2015 - 16:57

All great feedback Dave! This really snuck up on me somehow. The electrician will only be here for planning at first but I want to be able to give him as much info as possible to make his plans. Rod did the HVAC plan for me so yes I did all the load figures etc. then.
I guess another big question for me right now is, can I run my clean and dirty AC at the same level??2' apart??? I really can't find info on this or remember what I once thought I knew.
A while back I had begun by purchasing Greenfield for shielding clean power ( 10 circuits from Equitech) with individual #12 stranded wire and #10 ground stranded (ground wire is coated and to be included in the same greenfield as coated #12 hots). I planned to run the dirty with #12-2 Romex.
Rod said there's nothing wrong with Romex for all....if so do I need to shield it I wonder?? I guess I'll have to see what Davedog thinks is best as well. Any info you have on this is very welcome too.

dvdhawk Thu, 03/05/2015 - 21:20

Are you attaching these electrical boxes to / into the ICF, or framed walls? (Just curious where you are in the process.)

Electrical codes can vary by local jurisdiction, so I'd rely on your local guy for that. That's his job. Your job is to point and say how many. I'd defer to him on integrating the stranded THHN wire into the system, and the flexible conduit. You can buy armor-clad romex too. Honestly, I think the metal conduit, or metal jacket is more about protecting the wire from nicks and cuts over time than shielding. Davedog may say otherwise. Ironically, cutting either leaves you a nice razor sharp end which can chew the daylights out of the wire - which is why you absolutely have to use the little red insulating bushing they usually provide with sort of thing.

You've got 10 circuits of isolated power, how many do you need in your control room? If you ever envision yourself putting in a monster vintage console, they can take a big bunch of power. I'll probably provide more power to my control room than I will the tracking room. The sheer number of devices in the control can get out-of-hand. Tracking shouldn't need all that much power. I'm basing that on years of putting on a thumpin' good live production anyplace, indoors or out, that I can get two to four good 20-amp circuits of 120v. I can't image (nor would I tolerate) anybody that needed more power than that in a 30'x24' room to cut tracks. Because really, what would you have in the tracking that hogs up a bunch of power? [Beefy playback system, Bass rig, Hammond / Leslie / keyboards / keyboard amp]. Guitar rigs don't generally take much juice, drums don't take any. Your headphone distro won't take much.

Think about anything special you might require / desire, but let the electrician give you his input.

paulears Thu, 03/05/2015 - 23:22

Obviously my knowledge of US code requirements is almost zero, but I've a few questions. Here, our standard voltage has been "Europeanised" - for convenience everyone in Europe now describe, and calculate their loads by referring to 230V, 50Hz - even though typically, us Brits still have 240V, and the Germans 220V coming out of the sockets! Pretty well all homes and smaller industrial units are fed from a single phase. When two or more phases are available, it's 400V between them. Reading the last few posts it looks like in studios and smaller industrial spaces, you have multiple phases, which mean you have some outlets at the higher level, similar to our standard 230V? Our safety standards were viewed as tougher than the US, for many years and we even had a six foot between phases rule, but nowadays, we can have them next to each other if we wish. Our domestic style connector is the 3 square pin 13A plug - with integral fuse, but we use round pins for single and multiple phases.

I have more questions than answers now. In a studio, why would you need access to higher voltages, and different connector types? The only higher consumption devices I can think of are air con and heating?

The mention of clean and dirty supplies also confuses me. A few studios have outlets with a dedicated technical ground connection, but when multiple grounds are available on different sockets, one wrong connection usually wrecks any benefit these systems have. Most, but not all UK distribution systems bond the neutral and ground together at the point the power enters the building, which I thought was the same in many states in the US - and if this is the case, what is the difference between clean and dirty? I'm quite interested in the differences between US and UK. As I do much of my work in theatres, where temporary lighting systems are everywhere, a common contract requirement was clean power for sound. In practice, very few venues have this any longer as modern lights need power distributed to each one - so the notion of a centralised dimmer 'farm' with it's own supply is not that practical - the lighting guys see a power source, and just use it! Oddly, this doesn't seem to have increased the sound people's noise issues. Ground loops are still day to day hums to be fixed, but the old dimmer buzz that the sound people complained about is getting less, as dimming is distributed around the building, and, I guess, dimmer noise suppression is getting better.

On the sockets note - between my timber strips the sockets are surface mounted, with just the cable puncturing the wall panels and sealed. Most of my early studio 'leakage' was from puncturing the skin with the recessed types of socket mount - the damn things spoiled the sound transmission pretty badly.

On the US/UK differences, electricians here always laughed a little at the US system of twisting supply conductors together, with those screw on compression caps. We used them in the 50s to early 70s, but our national regs effectively banned them for being rubbish. Hence why we smiled seeing the US people continue - we were rather smug. Guess what? They're back, and now new younger electricians can't understand why why stopped using them. Fair enough, the new clever plastic ones are better than the old porcelain types, but it's been a 40 year gap in our way of doing things. Seems the US were right after all!

kmetal Fri, 03/06/2015 - 03:10

Electrical is my weakest area. In studio A from the 80s all the dirty stuff is standard height. The low voltage stuff runs across the ceiling above the drop ceiling tiles, and down thru the walls, or on the surface boxed in w pine. There's about 1' min of space between the Lv and dirty wire at any given time, and it hasn't been a problem with quad star cable. Generally each room has one main audio panel and a few outlets. It doesn't look like anything out of the ordinary for its building and zoning type.

If I were to do it again or the budegt wa bigger we would have put a couple of wall plates in each room. I hate cables all across the room.

vibrations1951 Fri, 03/06/2015 - 03:11

Dave, I'm planning on putting the 6" deep LV panel boxes on the framed walls so the face plates will end up on the surface of the final room treatment. They will penetrate through approx. 2 1/4" of wall treatment is my plan. The AC electrics will face on the outside of the wall tx as well but not need to penetrate the gypsum etc. attached to the outside of the studs. I'll stub through that and mount my boxes within the 2 1/4" of wall tx consisting of sound insulation encased by 1 1/2" furring strips and finished over with 1" (3/4") boards.

I like your advice about use of the electrician's expertise and what my role is. Perfect! Tanks. I'm a bit wound up right now and need to put this all together so I can make the most of his planning today. I'll check back later with my results. Thanks so much Dave! You really do come through in a pinch!!
Paulers, I'll respond later on.
Namaste

vibrations1951 Fri, 03/06/2015 - 03:14

kmetal, post: 425822, member: 37533 wrote: Electrical is my weakest area. In studio A from the 80s all the dirty stuff is standard height. The low voltage stuff runs across the ceiling above the drop ceiling tiles, and down thru the walls, or on the surface boxed in w pine. There's about 1' min of space between the Lv and dirty wire at any given time, and it hasn't been a problem with quad star cable. Generally each room has one main audio panel and a few outlets. It doesn't look like anything out of the ordinary for its building and zoning type.

If I were to do it again or the budegt wa bigger we would have put a couple of wall plates in each room. I hate cables all across the room.

Thanks for chiming in K!. Appreciate the thoughts. I also hate cables all over and am hoping to bite the bullet and put in more rather than less panels. Gottta go but I'll check back this eve.
Namaste

kmetal Fri, 03/06/2015 - 03:22

Oh just remember, we out the low voltage up higher just for pure visibility and back saving. Kinda just fake plugged a cable in to the imaginary box on the wall and picked the height, it was like 2-2 1/2' high. I've never heard of any rule of thumb for plate heights, or spacing either. Good luck today! Nice to hear there is progress!

vibrations1951 Fri, 03/06/2015 - 04:54

kmetal, post: 425826, member: 37533 wrote: Oh just remember, we out the low voltage up higher just for pure visibility and back saving. Kinda just fake plugged a cable in to the imaginary box on the wall and picked the height, it was like 2-2 1/2' high. I've never heard of any rule of thumb for plate heights, or spacing either. Good luck today! Nice to hear there is progress!

Yup perfect! That was my intent. Max said that's just what he did as well!
Thanks!
jp

dvdhawk Fri, 03/06/2015 - 11:33

Any place you envision high-voltage and low-voltage lines [audio / video / network] physically running in parallel, keep them at least 2ft apart - if you can. If they have to cross, cross at 90˚ where you can. So if you plan to keep your low-voltage runs low - (like baseboard height, or coming up through the floor), [[url=http://[/URL]="http://recording.or…"]putting your AC a couple feet above that makes good sense[/]="http://recording.or…"]putting your AC a couple feet above that makes good sense[/].

You will have to decide whether you want the nice clean look of flush mount plates & panels, (which makes a sizable hole you'll have to seal up), or whether you'd like to keep the wall penetrations small and go with surface mounting. Either will require some amount of attention with a fire-stop putty or caulk (Max's favorite hand-cream). I think it's 3M that makes fire putty packs to seal around the back of electrical boxes and make them air-tight. It's not going to have the same integrity as the rest of your wall, in terms of sound abatement, but it's a start by stopping air.

vibrations1951 Sat, 03/07/2015 - 05:38

So here's what we came up with. The LV panels will be at about 2.5' AFF fed from below. The "clean power" will come across the wall @ 4' AFF and the "dirt power" will be 6' AFF.
So now:Davedog and others here:
I have a used Equi=tech 10WQ. My electrician doesn’t have studio wiring expertise but does have experience with“hospital” wiring.

I have a control room, 2 iso booths and the main tracking space.

No “diry” power or LV wires will be run parallel with the “clean” power less than 2’ apart (with the exception of unforeseen crossovers, but if necessary, only at a 90 degree angle.)

Circuit wire questions:
Should I use Romex, stranded THHN or something else for my circuits from the equitech?

I have on hand #10 stranded (for ground) and #12 stranded, all of which I was going to pull the Greenfield I have on hand as well, for each clean power circuit.
Through my reading I now think that instead I should use #12/2 Romex for my “clean” circuits (from the Equitech) instead of the stranded THHN. And if I use the Stranded, I should likely twist the #12’s and run the #10 with it in the Greenfield untwisted.

Cost is always a factor but I don’t want to scrimp on such an important foundation piece of my setup!
Thoughts?

vibrations1951 Sat, 03/07/2015 - 05:59

vibrations1951, post: 425915, member: 34341 wrote: So here's what we came up with. The LV panels will be at about 2.5' AFF fed from below. The "clean power" will come across the wall @ 4' AFF and the "dirt power" will be 6' AFF.
So now Davedog and others here:
I have a used Equi=tech 10WQ. My electrician doesn’t have studio wiring expertise but does have experience with“hospital” wiring.

I have a control room, 2 iso booths and the main tracking space.

No “diry” power or LV wires will be run parallel with the “clean” power less than 2’ apart (with the exception of unforeseen crossovers, but if necessary, only at a 90 degree angle.)

Circuit wire questions:
Should I use Romex, stranded THHN or something else for my circuits from the equitech?

I have on hand #10 stranded (for ground) and #12 stranded, all of which I was going to pull the Greenfield I have on hand as well, for each clean power circuit.
Through my reading I now think that instead I should use #12/2 Romex for my “clean” circuits (from the Equitech) instead of the stranded THHN. And if I use the Stranded, I should likely twist the #12’s and run the #10 with it in the Greenfield untwisted.

Cost is always a factor but I don’t want to scrimp on such an important foundation piece of my setup!
Thoughts?

vibrations1951 Sun, 03/08/2015 - 03:42

Update:
I've settled on #12-2 Romex for all AC, both clean and dirty power. The stranded and Greenfield would have been a good choice but according to the Bill Whitlock paper and others, I would have needed to twist the hot and neutrals while leaving the ground relatively straight and then of course the pulling through the Greenfield. And the overall gains would be relatively little over the Romex. I settled on #12 even though #10 would provide a heavier ground, mostly because of the eventual challenges with hookups to receptacles etc. I feel that this should be fine.....I think....I hope!! Davedog are you out there?

The electrician will swap out all the THHN stranded and Greenfield I've got so I'm a happy camper.
Now it's time to move all construction materials and equipment to the center of the rooms and start the layout!!
I'm so pumped I can hardly stand it. We start pulling wire in 1 week! 2 hour Road trip Tuesday to pick up wire. I'm strongly considering colored LED floods type in the main tracking room and iso's. Tracks in the CR and a lighting controller of sorts instead of gangs of wall switches in the CR to control it all. Money bleed here we go!
Wish me luck. Any additional comments are welcome!
Namaste

Davedog Sun, 03/08/2015 - 19:48

Man I haven't heard "metallic flex" called "Greenfield" for a number of years. Of course, "Greenfield" is a manufacturers name as is "Romex" but due to them both having the largest market share back in the day, most electricians called these products by these names rather than what they actually are...ie: Metallic Flexible Conduit and NM-B. I don't know why anyone would spend the time and effort to "TWIST" wires together before putting them in a wireway unless you are living next to a sub-station. Grounding the metallic raceway at one end and having a continuous unbroken length of it will effectively shield as well as anything else....PLUS the cost of MC cable which is already twisted is a cheaper thing than the process described earlier.Also, these days, its illegal for metallic flexible conduit to be used in a wall. And here's the kicker on that one. You CAN use it in a wall in a concealed manner. It CAN NOT be over 6' in length. See what they do. Its about the impedance of the surface when used as a ground. They have found that over the years the interleaved wrapping of the metal fatigues and fails to maintain its "continuous length" as a connected ground source.....so now its more about motor whips and flexing to machinery.

Let me pontificate a bit on the differences between stranded and solid wire other than the obvious.

Electricity doesn't travel THROUGH the middle of a piece of wire. It travels on the surface area. Someone is going to get their back up and try and argure this but, while there may be currents of some sort found in the center section of a piece of mire, the main transmission of the current is on the surface of the wire. So here's the test.....which has more SURFACE AREA? A piece of solid #12 copper or a piece of stranded #12 copper?

Which has the greater ability to transmit a more complete set of frequencies? But we're only talking ONE frequency here for power....Right? 60 hz...50 for you Euro's. Uh huh....sorta....

Lesson Two. Proper height for devices.......Since this is to be a working area, commercial in nature and NOT a residential install, the rules are somewhat different. All outlets installed in a commercial space shall be adequate for the load served. There is no minimum height although for years 16" to center on general purpose recepts in a room has been standard. An outlet has to be at least 18" from a doorway. All outlets in a recording studio are governed by article 640 of the NFPA. Basically it calls out the sections in the book earlier that can be adapted to a studio. It talks about the proper grounding of a rack. It talks about grounding a dedicated circuit is about.

I also want to talk about 'clean' and 'dirty' power briefly.

A lot of guys are under the assumption that their UPS and conditioner are going to make all the power filtered to the point of a computer based system not freak with surges and spikes from equipment existing in a home. Refrigerators, disposals,AC equipment etc

It will help but the VERY best method is to create a NEW SERVICE through the use of an isolation transformer feeding a new panel completely dedicated to everything in the studio. Even a transformer of the standard non-isolting type is better than all these so called filtered devices you pay out huge dollars for. A new set of windings supplying your distribution will isolate effectively from anything upstream and of course an isolate transformer will block almost any sort of signal that could cause a hum of a spike in the service upstream.

More if needed.

vibrations1951 Mon, 03/09/2015 - 03:19

Davedog, post: 426010, member: 4495 wrote: Man I haven't heard "metallic flex" called "Greenfield" for a number of years. Of course, "Greenfield" is a manufacturers name as is "Romex" but due to them both having the largest market share back in the day, most electricians called these products by these names rather than what they actually are...ie: Metallic Flexible Conduit and NM-B. I don't know why anyone would spend the time and effort to "TWIST" wires together before putting them in a wireway unless you are living next to a sub-station. Grounding the metallic raceway at one end and having a continuous unbroken length of it will effectively shield as well as anything else....PLUS the cost of MC cable which is already twisted is a cheaper thing than the process described earlier.Also, these days, its illegal for metallic flexible conduit to be used in a wall. And here's the kicker on that one. You CAN use it in a wall in a concealed manner. It CAN NOT be over 6' in length. See what they do. Its about the impedance of the surface when used as a ground. They have found that over the years the interleaved wrapping of the metal fatigues and fails to maintain its "continuous length" as a connected ground source.....so now its more about motor whips and flexing to machinery.

Let me pontificate a bit on the differences between stranded and solid wire other than the obvious.

Electricity doesn't travel THROUGH the middle of a piece of wire. It travels on the surface area. Someone is going to get their back up and try and argure this but, while there may be currents of some sort found in the center section of a piece of mire, the main transmission of the current is on the surface of the wire. So here's the test.....which has more SURFACE AREA? A piece of solid #12 copper or a piece of stranded #12 copper?

Which has the greater ability to transmit a more complete set of frequencies? But we're only talking ONE frequency here for power....Right? 60 hz...50 for you Euro's. Uh huh....sorta....

Lesson Two. Proper height for devices.......Since this is to be a working area, commercial in nature and NOT a residential install, the rules are somewhat different. All outlets installed in a commercial space shall be adequate for the load served. There is no minimum height although for years 16" to center on general purpose recepts in a room has been standard. An outlet has to be at least 18" from a doorway. All outlets in a recording studio are governed by article 640 of the NFPA. Basically it calls out the sections in the book earlier that can be adapted to a studio. It talks about the proper grounding of a rack. It talks about grounding a dedicated circuit is about.

I also want to talk about 'clean' and 'dirty' power briefly.

A lot of guys are under the assumption that their UPS and conditioner are going to make all the power filtered to the point of a computer based system not freak with surges and spikes from equipment existing in a home. Refrigerators, disposals,AC equipment etc

It will help but the VERY best method is to create a NEW SERVICE through the use of an isolation transformer feeding a new panel completely dedicated to everything in the studio. Even a transformer of the standard non-isolting type is better than all these so called filtered devices you pay out huge dollars for. A new set of windings supplying your distribution will isolate effectively from anything upstream and of course an isolate transformer will block almost any sort of signal that could cause a hum of a spike in the service upstream.

More if needed.

Great Dave! Thanks so much.
Well I think when I moved here nearly 40 years ago I stepped into a 50 year time warp back in time so that and my lack of experience may account for my terminology D! LOL!

I do want to stick with code as much as possible because a lot of it makes sense (but not all in all cases) even though we have no inspectors up here.
So about surface area, I think of the outside of each strand so therefore the stranded has more surface area, unless the outside of the total wrap becomes the surface area, in which case it still seems to me that the convolutions created by the twisting, even though it is still #12 verses #12, and can cause more surface area like the convolutions of the brain???? But as the difference is only concerning 60hz, no biggie to my thinking, but please correct me if I'm wrong.

The Equitech isolation transformer provides my "clean" power and has been installed for a while and comes off a new entrance on its own circuit and should serve me well.

Please correct any of my assumptions. To me it looks like my originally stated plan should work real well. But I'm not wedded to the plan yet so if you think differently please advise. I won't come back and haunt you later, I promise! I realize the final decision is mine based on my reasoning of the most information I can gather and understand. I highly value your expertise and experience so your input counts very much to me.
Thanks again!

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