Hardwired or Haywire?

[richidoo]

Captive cords are rare nowadays, but I know Van Alstsine still does it on some products. He is about as "anti cable" as you can get, joking about using old rope in his RMAF demo last year. A post on his forum and typical AC knee jerk reactions got me thinking about this.

I think you could see any noise reduction due to distance attenuation on a scope or with one of those power line listening devices. Then comparing sub to main or demark would be straightforward. I can certainly imagine distance has an effect as most variables do with physics. Knowing Mother Nature as I do, I can assume there are many more variables we are not even aware of.

Transformers reduce the voltage of everything on the line and naturally "attenuate" noise in a way, but S/N is still the same before and after the tranny. I forget what the line voltage is for residential distribution, is it 14kV or 11.5kV or something like that where we live. so about a 100:1 reduction in noise after the step down. So we really only share the noise of our immediate 2-3 neighbors depending on the size of the transformer. Smaller transformers can supply fewer homes, so this is at odds with my suggestion above that aerial lines and smaller pole transformers are inferior to ground systems for noise. They are for RF noise picked up on aerial lines, since they are 10kV, it is a moot point. Don't believe anything you read on the internet...  haha
Each has its merits. My underground system sounds very good, but it is only 1 year old and sized for 60% more houses than are even built yet. Bobcats are the most significant source of noise in this neighborhood!

Rich

[shrinkmore]

Ya, and leaf blowers in mine, nearly every day in the fall - arghh!  I agree, that there are a lot of things that are unknown, but this has been an interesting thread and deepened my understanding of the issues involved.  Thanks for your knowledgable responses Rich.  

By the way, I'm posting a thread on the JJ's versus the NOS RCA's.  See ya there.

[bobrex]

Not to beat the horse, but speaking as an EE and as an employee of a power utility, where I'm involved in sending meter readings over the power lines, let's take a look at how a sub panel works.

A sub panel takes its feed from the main panel.  It is wired through a breaker to the same bus as the rest of the house.  Therefore, in simplest terms it is nothing but an extension cord and power strip.  Let's say you put in a 60 amp sub panel.  Your electrician will install a 60 amp breaker in the main panel, run a 00 wire (I think that's what code requires for a 60 amp circuit) to the sub panel, and then wire everything from there.  Oh, and code doesn't allow for a dedicated ground, the sub panel MUST be grounded to the main circuit.  

By default any noise found in the main box will be present at the sub panel.  There may be an slight advantage to running the heavy guage feed wire vs 10 or 12 (or even 14) Ga from the main panel, but my gut tells me that over the relatively short distances this will be negligible.  As Richie said, a neighbor on the same distrbution transformer can contribute to your noise problem.  Said neighbor's contribution will travel over a much longer path than any sub panel feed.  Think about it.

I only see 2 advantages to wiring a sub panel: 1) it helps make your electrician's boat payments and 2) it may allow you to dedicate circuits to your system if your main panel is full.  But honestly, that should be about it.

[Carlman]

I only see 2 advantages to wiring a sub panel: 1) it helps make your electrician's boat payments and 2) it may allow you to dedicate circuits to your system if your main panel is full.  But honestly, that should be about it.

Right, and you see this stuff every day.  I agree that it would seem unrealistic that there is any improvement.

There is a long list of crap I've done that 'shouldn't' make any difference and I have 2 EE friends that have nay-sayed almost every tweak I've made... And then I play them the difference, without telling them what I'm doing... and prove that a difference exists, generally for the better, and they leave shaking their heads trying to figure it out.

Cryo'd tubes, different DAC's, different cables, power cords, IC's, etc.  We've done it all.  It's not always black and white, the way engineers like it... but sometimes it blows their minds.  

So, try comparing a dedicated outlet to a non-dedicated one... or a subpanel'ed system to one running on the main panel sometime.  While you're at it, cryo the breakers and subpanel and use Walker SST on all the connection points. Line the back of the panel with ERS... Go nuts.  That's my plan...  This forum is for the insane, not the logical. ha.

[bpape]

Exactly.

I agree with those that say you SHOULD be able to measure anything that makes an audible difference.  Just goes to show that there are things that we may not necessarily understand WHAT to measure.  

I was half joking about the captive cords and half not.  I've been very tempted to hardwire power cables at the equipment end after I find the cord that I want.  To me, any time I can eliminate a connection, it can't hurt and can only help.

Bryan

[shrinkmore]

Bo,
Like Carl said, you see this stuff everywhere: electrical oriented critics chime in with cynicism when audiophiles talk about specialized electrical set-ups.    Electricians have been trained to believe a certain set of principles etc... and these serve them well in the areas of electrical management within which they work.   However, those principles seem have little to do with audio.  I offer one axiom that may expand the horizons of those electrically inclined:  Subtle changes in the input of electrical current can have big differences in the subtle sounds produced by audio equipment and loud speakers.  
I will say this yet again: I have installed two subpanels with dedicated lines and each time it has made a huge positive difference in the sound.  Whether a subpanel is better than a dedicated line, I am not sure, but I didn't have 5 slots on my panel and it is a relatively cheap tweak to run dedicated lines.  
By the way, it is not against code to put a second ground rod from the subpanel, as long as it is bonded from 6-10 feet from the main ground rod - at least in Georgia.  Of course, the bonding may at least partially defeat the purpose, but then again, it may not.

[richidoo]

I'm not positive but I would assume that a second earth rod on a subpanel even when bonded to the main earth rod does not remove the requirement of the subpanel to be grounded back to the main panel. The object is to prevent any current from being generated on internal wires when lightning strikes one ground system, but not the other. The different potentials create a huge current surge which will burn everything on the way. Profuse grounding conducts the lightning voltage everywhere so no current can flow. In theory... Of course houses still burn down which are properly grounded because lightning is not predictable.

Speaking of lightning, a good friend of mine, some of you know him as Lensman from AC, has a great theory about temporary electrical connections that I'd like to share since he hasn't found his way over here yet.

Microsurface peaks and valleys in the metal conductors prevent a perfect mating surface through which current can flow. Between the adjacent peaks that actually conduct by contact, there are millions of peaks that nearly touch but have a small air gap. When voltage potential builds between the two "mating" contacts current flows through the touching peaks with increased resistance which affects current flow, which is one way sound is affected compared to soldered joint. The resistance at these contact peaks also alows potential to exist at the non-contacting peaks with small gaps. Lensman's theory is that the tiny air gaps between adjacent non touching peaks are small enough to permit arcing even at small micro-voltages created by the high resistance contact point at the touching peaks. The arcing generates RF and all kinds of nasty effects that ruin the signal as it is passed through the temporary connection.

This is why the contact enhancement products work, even those which are not conductive per se, like Torumat and Cardas, they fill the gaps with a stronger dielectric than air and reduce the arcing. Maybe this is why Walker SST, which has silver particles in it to increase the number of contact points, is made with canola oil instead of petroleum grease, canola is a better dialectric. This aspect must be significant a advantage because polyunsaturated oils will harden over time like good oil paint. Petroleum as dielectric must be less effective than plant based oils. Vaseline is 2.6, same as castor oil at 80F, castor oil is used in audiophile oil caps. Linseed oil 3.1 (>60%unsaturated), cotton seed oil 3.1, Mineral oil used in industrial transformers is 2.1, Olive oil 3.1, crude petroleum oil is 2.1. Hydrogenated oils are much better dielectrics and would not oxidize (Crisco!), but they are too solid and would prevent contact. Partially hydrogenated castor oil might just be the ultimate contact enhancer with dielectric around 5-6! But it is disgustingly messy, sticky and stinky.

Olive oil is a monounsaturated fat which has identical dielectric strength as canola without the tendency to dry or oxidize.  Should make a fine contact treatment! And door hinge lube!

[bobrex]

I hate it when work intrudes on my posting schedule

[quote="CarlmanSo, try comparing a dedicated outlet to a non-dedicated one... or a subpanel'ed system to one running on the main panel sometime.  While you're at it, cryo the breakers and subpanel and use Walker SST on all the connection points. Line the back of the panel with ERS... Go nuts.  That's my plan...  This forum is for the insane, not the logical. ha.[/quote]

Actually, I have compared a dedicated outlet to a non-dedicated one.  I do have a dedicated line in my listening room.  My complaint was that someone claimed that the subpanel would provide isolation.  It doesn't.  All I did was state why.  A dedicated line ( or subpanel) doesn't provide isolation, it just means that there are no other noise inducing devices on that specific line.  That's not isolation, the line is still subject to any noise appearing on the main bus.  

Oh, and I do use other tweaks too - I did order Black Sand cables and I want to but some Grovers.  Hell, my system is virtually all tube, SET at that!  You can't get any tweakier.

Rich has elaborated on the "separate" ground issue and he is correct on the grounding requirements.  Two separate ground rods are the ideal recipe for a ground loop - There is no guarantee that both ground rods are at the same potential.  So the subpanel must be tied to the original ground.  That the electrician installed a second, redundant, and possibly worthless ground rod is more a profit point than anything else.

Shrink, I have a feeling that  you saw an advantage because the subpanel acted as a dedicated line.  If you could have compared your subpanel install to a dedicated line, you probably would not have heard a difference.  

I don't accept everything at face value.  Google FeSi and then take a look at the Shunyata Hydra.  See if you come away thinking that there's some bullshite going on here.  There's nothing wrong with taking a jaundiced eye to tweaks, some work, some don't.

[bpape]

A subpanel by itself does diddly - other than give you breaker slots.  There are a ton of other things that need to be done to get the bennies - subpanel or not.

Bryan

[richidoo]

Do tell!