Fundamental importance of power management


I have two systems, one is a fairly simple low power computer-based system in an office building environment.  The other is a bit more elaborate home theater system used for mostly 2 channel listening.  I have recrntly focused on upgrading the power management and delivery to both with great rewards.

I have been struck repeatedly by the effect of different power cables in my system, but I was astonished recently by the effect of putting my laptop source, all computer peripherals including external hard drive and sub on a low cost power conditioner strip I had laying around the office for multi media presentations.  Sound was always a little edgy with this system, even though the Audio Engine desktop amp was on a modest Belken power conditioner.  The effect of putting the computer set up and the sub on a separate conditioner in this noisy environment sounded like a major, major equipment upgrade.  

This increased my interest in cleaning things up powerwise ahead of my home system, even though I have a dedicated 30 amp breaker and 10 gauge supply line, and I would not think home power would be as dirty as an office building.  Each step including an upgraded power strip, conditioner and supply cable, replacing switching power supplies with linear supplies, and trying different power cables for gear has increased my enjoyment greatly, and seems to be allowing the character of each component to shine out, reinforcing the positive attributes of each and the whole.  Because this is a home theater, I have more equipment in a relatvely small area compared to an analog only set up, so some of the benefit may be mitigating self inflicted wounds.

So in my experience, power management seems critical, and the foundation all other “solutions” to getting the best sound must be built.  Down with plug and play.


Ag insider logo xs@2xknownothing
A lot of my posts are about basic guidelines to power management.


Keep your wall warts out of your analog zone. Use inexpensive shielded cable. Use a coaxial ground isolator for incoming cable TV/antennas.


But I do want to say that at a certain point we end up serving gear which is just too damn delicate. We shouldn't put amps which can discriminate between power cords up on an altar, we should ridicule them as having woefully under designed power supplies.
Erik, I think you are getting at this with the shielded cable recommendation and other solutions offered, but to some degree, I think much of the important work of cables is done outside the compent boxes, keeping signals in their appropriate lanes so to speak.  

At home, my HT receiver and sub are plugged directly into the wall and sounds best that way.  All other equipment is run through power strip and conditioned.  But yes, good power supplies reign supreme.
After years of trying power cables of different cable geometries - here is the basics of my observations...

Source Components with poorly designed power supplies (generally, most source components under $1000) can benefit the most

More pricey source components ($1000-$2000) that have better desinged power supplies, still benefit from better power cables, but the degree of improvement is less

Well designed solid state amps with large power supplies show the least "amount" of improvement if looking at dynamic performance, bass slam etc - but generally do improve in the areas of clarity and micro details (like venue acoustics). But you need the best power cables around to achieve this.

Tube amps appear to be less sensitive to changes of power cables, because their "heavy lifting" is achieved without drawing large amount of current.

I have tried power conditioners, but found they are of little benefit when compared to a well designed distrbution box, like those from Furutech

Having a dedicated line is the first thing that should be acquired and a quality outlet also.

Quality plugs on all power leads also provide significant improvements.

If your power is really bad then perhaps a re-generator.

I have heard there are other devices that perofrm well, but I like to keep it simple.

I also have pretty good mains power, which helps enormously

Regards - Steve
@knownothing you have an electrical fire waiting to happen with a 30 amp circuit feeding your equipment. Your home owner’s insurance will not cover a fire due to illegal electrical work such as that. The highest rating for CSA / ULc / UL approved 120 volt AC receptacles is 20 amps. You need to replace that 30 amp breaker with the correct breaker for your receptacle. 
On the subject of power cords, always use the lightest wire gauge required for your components. For example, if your amplifier draws a maximum of 5 amps at 120 volts, you should use an 18AWG power cord. The reason why is that your amplifier’s power supply has noise filtering that presents a low impedance to high frequencies, essentially stopping them at the door. If the power cord presents a lower impedance than the power supply’s filter, it defeats that filter by dropping the majority of the noise across the power supply input instead of across the power cord. Most people are under the mistaken impression that a heavier gauge power cord is better. This is why it is not. 

@Eric>
We shouldn't put amps which can discriminate between power cords up on an altar, we should ridicule them as having woefully under designed power supplies.

Blindjim>
I agree with your insights on addressing various aspects of the system's power delivery. Unquestionably.

however....
regardless the amp, preamp, or source component, EVERY thing that gets plugged into the buildings electrical service is or can be afffected by several things...

impeadance, resistance, conductance, and capacitance, as well as those issues which detract from a pure electrical potential's delivery of a steady state voltage and the frequency at which it is maintained.

EVERY power cord adds an element of all those electrical atrributes. to the down stream device. REGARDLESS that device.

some will argue too that even the fashion the PC is constructed, its dialectric, its connectors/plugs, and even how the conductors are laced, adds yet more audible characteristics to which ever component it is attached.

perhaps…. dunno.

i really don't want to be seen as derogatory or starting another cable bonfire though I do feel the need to, as the OP alluded, underline the notion that from the power pole/service box, to the device (s), what ever can be done to mitigate anomolies on those lines is critical.

also as the OP said, one simply will never know the outcome of addressing this area unless they do it first hand to the extent they reasonably can!

the 'size' of the feed is not nearly as important as is the way its fed from the service panel to the outlet, meaning the breakers, and conductors carrying the electricity.

a dedicated power line, bundled up with two dozen or so more latex and paper shielded romex runs are not the last word in maintaining separation from inductance.

this is another item that adds unwanted issues.
 
isolation is the ticket when it comes to most things audio, or such is my EXP so far. the better I've isolated devices from electrical problems, the better the results! Period.

just dressing cables so their runs aren’t a bowl of spagetti helps.

I won't make a point of how systems are setup at shows, but will take issue with individual setups in friends homes and my own.

Pass Labs has been for damn near ever deemed an outstanding line up of amplifiers. VAC is as well. so are any number of other makers, Merril, Yipsalon, Gryphon, DCS, EMM Labs, Bel Canto, etc.

every one of these makers amps or sources responds to different power management schemes, or power cords, differently.

so exactly where is that line wherein we should begin blaming the makers for providing us with pooer power supplies within their products

my thor line stage has an outboard PS and it is affected by various power cables, acordingly.

, VAC statement products... their top best they can do products have external power sups for their devices. we're talking upwards of components running six figures here, and even these over the top PS are affected by conditioners and power cords. not to mention what is flowing on the incoming power lines.

as I interjected 'isolation' here, these items are as well affected by harmonics in genera. and why racks, platforms and stands are yet another area to consider when attempting to formulate a system that is shielded as much as one can from environmental forces so the purest audio signal possible can be produced.

naturally, we get in where we fit in. not many can afford $8K amp stands for each component, or PCs that are as costly. it is prudent then to take steps to address as much of the electrical issues and harmonics as one is able.

we don’t know what we don’t know, BUT we sure as Hell can find out!

and we should.
@sleepwalker65 that’s fundamentally good advice on breaker.  Sounds good but will replace immediately.

On the 18 guage cable.  Maybe.  I have heard very few modern amplifiers with 18 guage cables.  I think my old Kenwood amp from the 70s had a lamp cord.

I have only heard one stock power cable that performed on par with an aftermarket cable, and that was versus one I built myself with hardware store parts, and it was not necessarily worse, just different.  In every other case and with every other after market cable either purchased or assembled by me out of parts, the aftermarket cord sounded better.  Wondering what others have experienced?
18 gauge power cables were just one example for a modest amplifier. If you have an amplifier that draws 10 amps, 18 AWG won’t do, and you’ll need to step up to 16 AWG, above that, to 15 amps use 14 AWG, then up to 20 amps use 12 AWG. Minimum ampacity with a tiny bit of headroom is what you should be aiming for. All cables need to be routed away from fields of alternating magnetic flux to mitigate inductively coupled noise. Remember though, all noise is generated externally to your analog equipment, and that’s where you want it to stay.
18 gauge power cables were just one example for a modest amplifier. If you have an amplifier that draws 10 amps, 18 AWG won’t do, and you’ll need to step up to 16 AWG, above that, to 15 amps use 14 AWG, then up to 20 amps use 12 AWG.

While I agree that the gauge of cables should be tailored to the component... 

From my own personal experience and observations....
  • I consider my amp to be "modest" 
  • It is solid state -  - NAIM 5i MKII integrated - 50 watts per channel
  • I have tried 14, 12 and 10 gauge power cables on it
  • The best it sounded is with the 10 gauge cable
  • The cables used were "home grown" - so
  • they all had identical plugs, geometry and wire quality
  • the biggest improvements was satisfying the high current demands  of very dynamic transient spikes.
I'm sure that 18, 16 and 14 gauge would be adequate for tube amps/components because they use voltage to do the "heavy lifting", but from my observations it would appear that Solid State gear requires a heavier gauge power cable to handle the high current draw.

Just another opinion  :-)
 
@blindjim 

Nice post. I agree with pretty much all of it.  Theory is a fine place to start, but I think folks just need to try different solutions for themselves.  Results might surprise you, and then you can try to figure out why it works while enjoying great music!

Side note to power discussion but mentioned by you: I have put equal effort recently on vibration control for my analog front end which has been a real eye opener.  I like results.

@erik_squires

Thanks for the link to your blog, great advice there.  

Side note: I am all in on your focus on room acoustics first.  I abandoned trying to get good sound in my living room with lots of glass, plaster and tile, and retreated to put my energy into a purpose built space in my basement described in some detail on my system page.  I put all my money and effort initially on the AC service and the room design, and have been building around carefully selected main components ever since with focus on synergy.  Benefits of recent power management easily realized with decent listening space as a backdrop making it possible to hear even subtle effects of each change.

@williewonka

Interesting conjecture on tube versus solid state power cable requirements.  Off the top, what gauge wire would you recommend for linear power supply for tube phono preamp?  Also, shielded versus non shielded as a place to start?
Pardon my being argumentative; but, all talk of room acoustics first seems to me is putting the cart before the horse...  Room acoustics “cannot” improve the quality of the sound emanating from the sources. That not an opinion. Making the best of the room you start with, “room acoustics” is natural; but cannot improve the quality of the sound from your reproduction system. In fact, if you don’t get adaquately good sound from your system as a starting point - you won’t have the ability to “fine tune” room acoustics. Imo, fwiw.  
However, I do believe it is entirely sensible to make the best of the room you have, regardless of the quality of the sound your components allow. 
Hi @ptss 
You make a bit of a straw man argument here:

but, all talk of room acoustics first seems to me is putting the cart before the horse...  Room acoustics “cannot” improve the quality of the sound emanating from the sources.


Absolutely no one has made that claim, nor has anyone claim the room itself creates music.


However, the room is the largest, and measurably biggest filter and alteration of the perceived sound, especially when compared to power, interconnect, and speaker cables. As you put it: That is not an opinion.


Room acoustics can create peaks and nulls of 20 dB or more. No other component besides the speakers themselves will alter the sound you hear this much. The interaction between speaker and room has many other documented, and undeniable effects on the perceived experience such that it overwhelms everything else.


Speaker and cable contributions are so slight as to be lost in the realm of hearsay, argument and placebo effects. That is not an opinion.


Good room acoustics make a room more speaker and equipment friendly, and will very likely outlast your other equipment. They can, arguably, be rather cost effective when compared to expensive power, speaker and interconnect cables.


Best,

E
I agree with your last paragraph :)
@knownothing - apologies for the delay in responding - been out of the country for a few days.

RE:
Interesting conjecture on tube versus solid state power cable requirements. Off the top, what gauge wire would you recommend for linear power supply for tube phono preamp? Also, shielded versus non shielded as a place to start?
I am assuming you are refering to the cable from the mains supply to the power supply and not the cables from the power supply to the phono stage?

I think you would probably be OK with a 16 gauge power cable.

As to whether shielding is required or not is very dependent on your environment and how noisy it is.

Most home audio is in a releativeliy noise free environment provided the cables are well spaced and are not parallel to other cables.

Granted there are lots of radio devices all around us these days, but in the case of a power cables the impact of RFI/EFI from radio devices is negligable - at least in my house

I think that in most cases the impact of a sheild (i.e. the additional capacitance and internal noise propogation, etc...) outways the beneficial effect of a sheild handling external RFI/EFI.

In a studio environment or on stage, where all cables are run all over the place and often run in parallel in some kind of conduit, then sheilded cables provide many benefits.

I have conducted test on my own cables in my system and found that having a space of approx 3cm between all cables will generally negate the effect of RFI/EMi between cables

I’m a long time DIYer and make my own cables from scratch using an advanced Helix spiral geometry that provides many benefits not attainable by using commercial bulk cable products or even some the best commercially available products.

If you are interested take a look at...
  • http://image99.net/blog/files/category-002ahelix-power-cable.html
  • They look complex to build but after winding the first helix it becomes quite easy :-)
  • They are very effective at rejecting noise and and additional benefit is that HELIX cables can be placed in parallel very close to each other without any RFI/EMI impact
  • e.g. - I recently held the Helix interconnect connecting the turntable to the phono stage, in parallel to a power cable (i.e. they were clenched in my fist) with the amp at full power and there was no additional noise introduced.
  • You could start by making a cable out of household Romex, just to gauge their effectvieness and then progress to the more expensive wires like Duelund or the Silver PLated Mil-spec, detailed on my site.
  • PLEASE NOTE: I warn against the continued used of solid conductors for power cables - since they are prone to breaking and can become a fire risk.
If you have any further questions - ask away :-)

Regards - Steve

@williwonka

Thanks for the comments and insights on shielded versus non-shielded wire.  Great wire building instructions.  Nice system too.