[putz]

I've read through the threads on dedicated lines but have not seen any that explain what the benefit is for putting in a line. My friend who is an electrical engineer thinks I'm nuts and wants to see scientific documentation that justifies the expense. I had an electrician look at my panel and it's full and too old (about 50 years) to add to so I would have to put in a sub panel to do the dedicated line.

I don't have any hum issues with my system and there's no easy way to know what effect a dedicated line would have on my sound quality without actually having the work done.

From what I've read here and in other forums, everyone swears by the improvement in sound from adding a dedicated line and I would like to experience that as well. But what's the science behind this effect? I'm willing to settle for a rational explanation.

[Folsom]

"Scientific documentation" ? You are nuts. First there's no science involved here. It's engineering. There's nothing "new" to need a study done.

The reason it's so much better is because the noise from all the other devices in your home are not going to be on the line, and you can run high quality lines that are able to provide more current. JPS Labs has the best stuff I've ever seen but it's spendy. Next would be Cardas then VH Audio's cryo'd. The JPS appears to be in a league of it's own since it is twisted I believe.

Twisting attenuates a lot of noise because it lowers the induction significantly. You could be spend $1200 on the wire, but the performance gain may seem like you spent a lot more.

Think about it this way, regular parallel romex attenuates much less, it's closer to an antenna than twisted cable.

[undertow]

Its about isolating components in the audio chain for other varying ground loops, frequency variations etc... born in the rest of your house. Essentially all audio components are far more sensitive with their own dedicated power supplies than other devices like your refrigerator, toaster, even computer because you more or less expect them to just be turned on and off, but to perform at its best sound quality on a consistent basis audio components require a little more "Imagination" than your normal electrician will warrant. To get this AC line to perform on a consistent basis it is in fact a good idea to isolate your audio gear you likely spent good money on in order to perform at its optimal level.

By the way just like an Aircraft has several power systems it's done to make redundant, and isolated circuits in order to have no disruption in performance, or service which is the same idea here. But when it comes to "Noise" most components don't need so much noise isolation from that accept your audio gear because it will amplify it into sound unlike your toaster just making varying degrees of heat which you don't care if it cooks accurately every single time in the same amount of seconds per piece of toast! In other words a split second of bad power will show up as a problem thru an audio chain, not so much other household appliances, or gadgets.

Another thing is there are no guarantees dedicated lines will solve all or any problems, nor go from a 6 to a 9 on the sound quality scale, however it can help specifically people with unknown bad AC or much older systems as you explain is installed in your house. So there could be a significant benefit, or one that may do just a little.

[Speedskater]

It simply adds distance from other power line noise generators. In 2016 almost any produce that you buy that uses AC power has the potential to generate power line noise. An expert suggest that there may be 20 to 30 of these noise sources in the average home.

Everything you need to know about AC power and A/V systems (and a whole lot more) is in these three papers.

Integrating Electronic Equipment and Power into Rack Enclosures
Optimized Power Distribution and Grounding for Audio, Video and Electronic Systems
Middle Atlantic Products
http://www.middleatlantic.com/resources/white-papers.aspx

An Overview of Audio System Grounding and Interfacing
by
Bill Whitlock, President
Jensen Transformers, Inc
http://centralindianaaes.files.wordpress.com/2012/09/indy-aes-2012-seminar-w-notes-v1-0.pdf

Power and Grounding For Audio and Audio/Video Systems
-- A White Paper for the Real World
by
Jim Brown
http://www.audiosystemsgroup.com/SurgeXPowerGround.pdf

[Folsom]

It simply adds distance from other power line noise generators. In 2016 almost any produce that you buy that uses AC power has the potential to generate power line noise.

Good god man! And you have the nerve to talk about safety and regulation with us!

I can't imagine what your house smells like with produce using AC.

[Speedskater]

That statement came from the go-to noise & interference expert Jim Brown.

You're being serenaded by hundreds of switching power supplies and microprocessors. If they drift, they're SMPS. If they don't, they're from a microprocessor. I'd take a WAG that the average residence has at least 30 such noise sources. Virtually every wall wart, battery charger, PS for low voltage lighting, computer, computer accessory, variable speed motor controller, etc. is an SMPS.

[undertow]

That statement came from the go-to noise & interference expert Jim Brown.

You're being serenaded by hundreds of switching power supplies and microprocessors. If they drift, they're SMPS. If they don't, they're from a microprocessor. I'd take a WAG that the average residence has at least 30 such noise sources. Virtually every wall wart, battery charger, PS for low voltage lighting, computer, computer accessory, variable speed motor controller, etc. is an SMPS.

I believe he is pointing out the Typo in your "Quote" .... PRODUCE as in Fruits and Vegetables... I assume it should say Product instead.

[Speedskater]

If that's the biggest mistake I make today, I'll be happy.

When I go back and look at my posts from long ago, I find all kinds of mistakes.

[Wig]

Guys,

How many outlets do you recommend for a dedicated line? Also, does a 20A breaker signifies that I have dedicated lines?

Thanks,
Wig

[werd]

Dedicated lines "rock" quite literally.  Aside from noise you do not want multiple transformers on one line. It's bad enough you have put a pre amp and dac or what ever you got in your system in parallel with an amp. But still better than adding unneccessary wall outlets with junction boxes or lights!  . Sucks the dynamics. Guess you can turn everything off on the line but there are still junction boxes breaking up the single 10 or 12 gauge wire. Wire is cut at outlets and resent. Dedicated as in an uncut wire from fuse box to outlet supplying a conditioner or amp.  One two receptacle outlet per 15 or 20 amp circuit gets you to the local community transformer untethered. Front ends including preamps you can run multiple outlets but try and get them off your amps. Dedicated lines are all about the amps. 

[G Georgopoulos]

Good god man! And you have the nerve to talk about safety and regulation with us!

I can't imagine what your house smells like with produce using AC.

Hi jeremy

speedskater quotes reference to back his points,be nice to him,cheers guys...

[Speedskater]

Guys,
How many outlets do you recommend for a dedicated line? Also, does a 20A breaker signifies that I have dedicated lines?
Thanks,
Wig

To find out if it's a dedicated line, turn off the circuit breaker. Does everything else in the house still work.
If all your equipment is in one rack, then you only need one wall outlet box, with as many receptacles as needed.
If your equipment is scattered about the room, then as many outlet boxes as are needed.
All the outlet boxes should be feed from one centrally located junction box.

Note: to a electrician, an outlet is the box in the wall. A receptacle is what you plug a cord into.
One manufacture seems to have forgotten that.

[maty]

In Europe is a very good idea to install a super immunized differential, class A to the dedicated line. Schneider is a good mark.

SI ilD 2x40A 30mA SCHNEIDER

Sensitivity of RCDs to disturbances

-> http://www.electrical-installation.org/enwiki/Sensitivity_of_RCDs_to_disturbances

[Spanish] -> http://www.emb.cl/electroindustria/articulo.mvc?xid=178

To English -> http://www.microsofttranslator.com/bv.aspx?from=&to=en&a=http://www.emb.cl/electroindustria/articulo.mvc?xid=178

[FullRangeMan]

From what I've read here and in other forums, everyone swears by the improvement in sound from adding a dedicated line and I would like to experience that as well. But what's the science behind this effect? I'm willing to settle for a rational explanation.

Too much equips at same line will reduce tension(unless its a hi Current/Amp) and poor equip performance will result.

[ACHiPo]

"Scientific documentation" ? You are nuts. First there's no science involved here. It's engineering. There's nothing "new" to need a study done.

The reason it's so much better is because the noise from all the other devices in your home are not going to be on the line, and you can run high quality lines that are able to provide more current. JPS Labs has the best stuff I've ever seen but it's spendy. Next would be Cardas then VH Audio's cryo'd. The JPS appears to be in a league of it's own since it is twisted I believe.

Twisting attenuates a lot of noise because it lowers the induction significantly. You could be spend $1200 on the wire, but the performance gain may seem like you spent a lot more.

Think about it this way, regular parallel romex attenuates much less, it's closer to an antenna than twisted cable.

I used 12/3 and 10/3 Romex in a dedicated 20 amp circuit (10/3 to the amps, then 12/3 to the rack--snipping off the unused conductor), both of which are twisted rather than parallel, so you get good noise rejection.  The 10/3 is a bear to work with, which is why I switched to 12/3 to feed my lower current devices (which is still way oversized for the load).  Oh, and it's cheap.

[Brad]

Having a dedicated line run for audio was a bigger change for the better than any single component upgrade I've done.   

I think the total cost was about $200, including a cryo'ed P&S outlet.   One nice thing for me is the electrical panel is within 20 feet of where I had the outlet installed - that kept the cost down.

[Speedskater]

Although the twisting is good, after read in Bill Whitlock paper, 12/2 and 10/2 Romex® might be better than three conductor Romex®. True you loss the twisting but you gain symmetry.

[Nordkapp]

What about using an isolation power transformer from the likes of PS Audio, Torus, Bryston, Furman etc ? I ask only because I had similar concerns about line noise and the varying degrees of line voltage through the the course of the day. According to all I have read, this is typically a fairly easy way around aforementioned problem.

[Early B.]

What about using an isolation power transformer from the likes of PS Audio, Torus, Bryston, Furman etc ? I ask only because I had similar concerns about line noise and the varying degrees of line voltage through the the course of the day. According to all I have read, this is typically a fairly easy way around aforementioned problem.

Do both. A dedicated line doesn't negate the need for power conditioners, high end outlets, power cables and ICs to reduce noise, etc.

[Folsom]

Do both. A dedicated line doesn't negate the need for power conditioners, high end outlets, power cables and ICs to reduce noise, etc.