Dedicated Line Advise

Not trying to start any argument here, but there is absolutely no reason for the equipment to be on the same phase at all.  The AC is converted to DC within the device, so AC voltage phasing is irrelevant.

As long as the dedicated line have hot, neutral and ground going back to the panel and do not share neutral or ground before the panel. you are fine.

Also, any electrician worth their salt will want to have your AC panel loads balanced on both phases. 

I read that many posts about dedicated lines and some advocate placing them on the same phase.  But, if your equipment carries a large load =, that load must be balanced on the AC panel to avoid overloads.

I ran dedicated lines for my audio equipment.  My house fortunately is on a raised foundation, so crawling underneath the house was the way to go.  Hot, neutral and ground all back to the panel and not shared.

I have to Audio Research REF 250 mono amps connected to the individual dedicated lines back to the panel (on the same phase at the panel) and one Mark Levinson 23.5 connected to the other phase via a dedicated line. 

My low level equipment are all connected to a Transparent Audio Power Isolator 8 line conditioner, then via a dedicated line back to the panel.

I tried to balance the loads as best I could.

Noise floor is just gone.  No ground loops, no buzz, no noise whatsoever. no equipment's ground lifted via cheaters.

Noticeable difference from when I didn't have dedicated lines.

Being an Electrical Engineer, I know that AC is AC and DC is DC and every piece of equipment I use converts the AC to DC internally.  Therefore, phase absolutely does not matter and my system's sound is wonderful.

If you are going to put all your equipment on the same phase at the panel, try to make sure your house loads are balanced at the panel.

enjoy

It seems that my circuit box is balanced...
   Left                        Right
- furnace,              - refrigerator 15amp   
  30amp linked.     - light duty 15a
- A/C 20amp         - dryer, 30amp, linked
- light duty 15a      
                              
But, the original electrician did a poor layout of the breakers for my purposes. The only open area for expansion is in the middle of the box. High current breakers are at the top and the bottom.

Minorl - my only preference for keeping the gear on the same phase is for safety only.

In the event of some very rare condition(s) occurring in audio components, having the components split between two phases could result in (and I stress very rare and could) - a voltage difference between present on the chassis of two components of 240 volts and not 120 volts if the components were on the same phase.

e.g. I’ve read of members "removing the ground pin" in order to get rid of hum - this is one action that I believe can have dire consequences, since it defeats the purpose of the ground wide in that components - the chassis could become live if something inside fails.

e.g. I’ve also experience third party power cables that were wired incorrectly, i.e. the live wire went to the neutral side of the IEC connector, which, from the perspective of AC makes no difference in operation - however from a safety perspective it could mean that the neutral side of the input to the power supply is live.

Most of these issues may not impact general component operation, but there are design standards for a reason - safety!

I also believe there are other factors pertaining to the age of the external supply lines and transformers that might result in noise being transferred to the components, but that may only occur when the electrical infrastructure is old - which does not apply in this case.

Won't happen? - maybe not, but I've lost count of the number of musicians that have been electrocuted from what was supposed to be - safe amplification

I also do not wish to start a debate - but I thought I would provide the above info for everyone’s consideration.

BTW - I’m also in the EE camp :-)

Cheers

Minorl,

Having worked on this issue extensively with many different systems, the chance of getting ground loop hum when powering equipment from the two opposing phases in your panel is greatly increased.  While I agree that in theory it should not matter, in practice in most cases it does.  

You mention that your two amps are powered from the same leg in your panel while your front end is powered from the other leg, however you also mention that

"My low level equipment are all connected to a Transparent Audio Power Isolator 8 line conditioner, then via a dedicated line back to the panel."

This could be the one reason that you don't experience this phenomena, as an experiment why not try to eliminate this one and see (hear) what the result is. 

Coming from the EE camp also

 Good Listening

Peter

Having worked on this issue extensively with many different systems, the chance of getting ground loop hum when powering equipment from the two opposing phases in your panel is greatly increased. While I agree that in theory it should not matter, in practice in most cases it does.

According to a reference authored by world renowned authorities on relevant aspects of electrical and electronic design, which was cited in this thread, it even matters in theory. See the first of my two posts in that thread dated 5-16-2013, which provides brief relevant excerpts of their paper, as well as my comments on it. The paper was initially cited and commented on in the thread by electrician extraordinaire Jea48 (Jim).

The thread also contains further discussion of both this issue and the criticality (or lack thereof) of load balancing, by me, Minorl, Peter (pbnaudio), and Jim (Jea48) among others.

It would seem that those on opposing sides of these issues will just have to agree to respectfully disagree. As for me, FWIW, I’m with Peter and Jim on these issues.

Best regards,
-- Al