The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!

Featured:
   

2017 NEC and Related
2017 NEC
Now Available!

   
Recent Posts
Correct rotation, wrong sequence
by Potseal
Today at 03:14 PM
Industrail Control Panel bonding per 409.108
by sparkyinak
Yesterday at 06:29 PM
Calling all Non-US members!! (Non-US only)
by aussie240
12/07/16 02:39 AM
Photo Upload Tutorial
by DanK
12/06/16 11:35 PM
Sprinklered equipment 26-008
by bigpapa
12/02/16 04:24 PM
New in the Gallery:
12.5A through 0.75mm˛ flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 11
HotLine1 10
Potseal 9
sparkyinak 8
Texas_Ranger 7
Who's Online
0 registered (), 202 Guests and 4 Spiders online.
Key: Admin, Global Mod, Mod
Page 1 of 3 1 2 3 >
Topic Options
Rate This Topic
#24180 - 04/07/03 11:54 AM Wiring a Basement Recording Studio
mchimes Offline
Member

Registered: 04/07/03
Posts: 15
Loc: Alexandria, VA, USA
Hi Folks,

I'm a musician about to build a studio in my basement. I got tired of the half-wrong electrical "folk wisdom" on all the recording forums about how to wire a studio . . . so I thought I would seek out advice from real electricians. And judging from the responses to several searches, I know I'm in the right company.

Here is the situation:

I want to spend as little as I have to for my power to be safe, relatively quiet*, and reliable (i.e. enough of it!)

I don't know if I need just dedicated branch circuits, IG circuits, branch circuits from a subpanel, balanced power, separation transformers, etc. or a combination of the above . . . I have some ideas about what I would need, but I am curious to know what you would do if you were in my situation.

I will need power to:

1 computer & display (CRT)
6 audio components (including mic pre-amps, interfaces, small mixer)
2 guitar amplifiers
1 power amplifier
Various small peripherals (USB hubs, etc.)

I have a small ADC UPS and Furman power conditioner (electrically speaking I think it is a glorified strip plug w/ some filtering and surge protection)

I already have some "dirty" power down there for lights and receptacles . . . but what do you think I would really need to do to meet my goals for the sensative audio gear?

Thanks,
Mike

*I don't know what the measurement parameter would be for line noise. . . but, in practice, this would mean the noise floor of the system could never interfere with the recorded sound.

Top
Work Gear for Electricians and the Trades

Work Gear for Electricians and the Trades
Work Gear for Electricians and the Trades
Arc Flash Clothing, Gloves, KneePads, Tool Belts, Pouches, Tool Carriers, etc. etc....

#24181 - 04/07/03 12:23 PM Re: Wiring a Basement Recording Studio
Bill Addiss Offline
Member

Registered: 10/07/00
Posts: 4196
Loc: NY, USA
Mike,

You pose an interesting question from a design standpoint. I am assuming at this point that you are not asking for instructions on how to do this yourself, which would be outside the scope of this Forum.

Bill

Top
#24182 - 04/07/03 01:56 PM Re: Wiring a Basement Recording Studio
mchimes Offline
Member

Registered: 04/07/03
Posts: 15
Loc: Alexandria, VA, USA
Bill,

I'm mainly aksing what approach an electrician would take to achieve the goals I mentioned.

I'm not looking for you guys to walk me through how to wire an outlet, but to steer me in the right direction. I may hire an electrician- but I want to know enough be able to thoroughly explain what it is that I need . . . and I think I might know better after getting some of your opinions.

In short . . . if you guys were putting in a recording studio in your basements on a budget . . . How would run the power?

Thanks,
Mike

Top
#24183 - 04/07/03 02:27 PM Re: Wiring a Basement Recording Studio
RR Offline
Member

Registered: 11/15/02
Posts: 15
Loc: Yorba Linda, CA
Mike,

Sounds like an interesting project.

Typically, an Electrican will only install what has already been engineered. I would contact a local design/build Electrical Contractor and explain to them what you are looking for. A design/build contractor is the best of both worlds. The in-house design team will engineer and consult with you on your preferences while the Electrican team will perform the installation.

Top
#24184 - 04/07/03 02:46 PM Re: Wiring a Basement Recording Studio
Bill Addiss Offline
Member

Registered: 10/07/00
Posts: 4196
Loc: NY, USA
Mike,

Figuring out how many circuits are needed and laid out will depend on your loads and which ones will be used at the same time and where this equipment will be. Look at your nameplates and add the values together. An Electrician should have no problem installing wiring for equipment that you have if you can tell him where and how it will be used.

IMHO the interesting, and more difficult part of this project has to do with power quality and ways to control different types of noise. Is that what you're asking about?

Bill

Top
#24185 - 04/07/03 03:15 PM Re: Wiring a Basement Recording Studio
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
Mike,

In terms of the number of branch circuits needed, a single 20A branch would provide up to 2400 watts, which should be ample for your list of equipment. (Unless that power amp is big enough to blow out the basement walls ).

I've seen some studio designs recommend balanced power, but frankly I think that in a basic set-up such as this it's overkill.

Unless your power grid is particularly noisy, I think you'll find that having a dedicated branch circuit back to the main panel would be sufficient. It might be worth opting for larger cables than code would require, as this would help keep the supply impedance down thereby reducing noise fed back into other equipment from items such as class B power amps.

If you're particularly concerned about keeping induced hum to a minimum, then maybe go with a metallic conduit installation so that the conduit will act as an electrostatic shield.

Top
#24186 - 04/07/03 03:47 PM Re: Wiring a Basement Recording Studio
arseegee Offline
Member

Registered: 01/28/02
Posts: 321
Loc: Statesboro, GA USA
mchimes, I use to do pro audio and recording systems before i got into the electrical field. I have some 10 years experience in that area. I would run a seperate sub panel for all you recording equipment and install a Transient Voltage Surge Suppressor on that sub panel. Now Gronding and Bonding is the key for clean audio. All Racks and Rack mount gear HAS to be effectively bonded. Seperation of you audio and power cabling is a MUST!

Email me if i can be of any help....and yes dont you love paying $125 for a Furman power conditioner that is little more than an outlet strip...lol

Top
#24187 - 04/07/03 04:17 PM Re: Wiring a Basement Recording Studio
NJwirenut Offline
Member

Registered: 09/15/01
Posts: 816
Loc: Bergen County, NJ
I have been involved in wiring audio and video editing suites in the past, both power and signal wiring.

For minimum hum and noise, a "balanced" power configuration was used. Critical equipment branch circuits (those feeding equipment racks, mainly) were fed from a special isolation transformer with a center tapped secondary, with the center tap grounded. Voltage from "hot" to "neutral" blades of receptacles is 120 V, but hot or neutral to earth ground is 60 V. All circuits were isolated ground, as well. RF noise filter installed on the power entrance to each rack.

All racks and cabinets bonded together with 2" wide copper strap, running back to the distribution panel, and on to the main service ground.

All power wiring in EMT for RFI shielding, with care taken to avoid parallel runs of power and signal wiring.

Top
#24188 - 04/07/03 04:42 PM Re: Wiring a Basement Recording Studio
Electric Eagle Offline
Member

Registered: 04/20/02
Posts: 928
Loc: Alpharetta, GA
One basic way to reduce noise is to use at least 1 size larger wire than required for the load and put your circuits "in phase" - Most panels this means using every other breaker position.

Top
#24189 - 04/07/03 06:08 PM Re: Wiring a Basement Recording Studio
Bjarney Offline
Moderator

Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
Be certain that your electrician thoroughly understands and applies {1999} NEC Articles 640, 530 and 250 and the components served from transformer-isolated sources in 640-7(b.), 530-70, -71, -72, -73, 250-146(d) and 410-56(c).

The NEC derfines this 60/120V source as technical power. There is the potential for some serious abuse with all the currently advertised so-called “balanced-power” isolation transformers furnished with NEMA 5-15 or 5-20 receptacles, that seem to contradict 530-73(a)(4) All 125-volt receptacles used for 60/120-volt technical power shall be uniquely configured and identified for use with this class of system. Don’t overlook acceptable grounding methods for the center tap of the isolation transformer.

Also, anticipate that triac-based light dimmers can very effectively interfere with audio signals.




[This message has been edited by Bjarney (edited 04-07-2003).]

Top
Page 1 of 3 1 2 3 >



ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals