Get Free, Friendly, Expert Advice
Call 1-866-244-8796 or email

Designed and Manufactured in Canada Since 1980


AxiomAudio Blog

Outdoor Speaker Placement

Speaker Placement: Unusual Room Layouts and Elevating Speakers

Positioning Floorstanding Speakers

Wall'O'Fame
Greetings fellow Axiom owners...
HG Rosewoods Part 3
Who's Online
3 registered (Kevin1, exlabdriver, J. B.), 116 Guests and 4 Spiders online.
Key: Admin, Global Mod, Mod
Financing
Forum Stats
13295 Members
11 Forums
22826 Topics
403266 Posts

Max Online: 378 @ 02/24/13 04:33 PM
Top Posters
Ken.C 17741
pmbuko 16259
SirQuack 13318
CV 11146
MarkSJohnson 10832
Meanwhile On Facebook

A very fond farewell party last night . . . we miss you Noreen!

Hope everyone's got their summer favourite playlists cued up for the weekend! W...

(y) Love this customer review of the M2s! "the first time listening to my new a...

These LFR1100 speakers in custom Eggshell White are on their way to Taiwan (yes,...

Page 7 of 8 < 1 2 3 4 5 6 7 8 >
Topic Options
Rate This Topic
#77223 - 01/19/05 09:27 PM Re: You might think I'm crazy, but I'm not...
JohnK Offline
shareholder in the making

Registered: 05/11/02
Posts: 10363
No, Pat, speaker cables serve as a guide(i.e. more like a monorail than a hose)for the electromagnetic field transmitting the power. It's a relatively high current into a relatively low speaker impedance and it's essentially immune to interference in the home. Shielding, twisting, etc. may be helpful in preventing the very weak signals carried by interconnects from being affected by interference, but are unnecessary for speaker wires and are yet another marketing ploy.
_________________________
-----------------------------------

Enjoy the music, not the equipment.



Top
#77224 - 01/20/05 08:07 AM Re: You might think I'm crazy, but I'm not...
Ajax Offline
axiomite

Registered: 12/30/03
Posts: 6246
Loc: Cleveland, Ohio
If you're going to go for aftermarket power cords, at least consider this

And, this

Can We Hear Differences Between AC Power Cords? - An ABX Blind Test. December, 2004


The Results

The complete Excel spreadsheet with all test results and participant comments can be accessed herein. After the test, Manny spent quite some time analyzing the results and responses to a post-session questionnaire he composed. I owe much of the following analysis to him.

The total number of correct answers was 73 out of 149, which amounts to 49% accuracy. That is no more accurate than flipping a coin, and therefore, no statistically significant detection of power cable differences.


In the spirit of fairness, this was also stated.

Conclusions

To many in the engineering community, blind ABX is an accepted experimental design. Using the blind ABX protocol, we failed to hear any differences between an assortment of generic power cords and Nordost Valhalla. Therefore, we cannot conclude that different power cords produce a difference using the blind ABX protocol. However, we also cannot conclude that there are no differences. We simply failed to prove that differences can be detected to a statistically significant degree using a blind ABX protocol.


John Johnson, who comes from a scientific background, suggests that if there are differences between cords, they appear to be so subtle that a blind ABX test cannot discern them with small numbers of participants. Failure to discern them could be due in part to the time it took for cable changes, and the possibility that accurate auditory memory is shorter than that. It may be necessary to switch between cords in a much shorter time.

Unfortunately, as John notes, we don't know of a way of accomplishing fast power cable changes, since, unlike interconnects which can be simply switched between A and B with the equipment all still powered on and playing music, changing AC power cords requires turning the equipment off, switching the cords, and then powering them back on.


_________________________
Jack

"People generally quarrel because they cannot argue." - G. K. Chesterton

Top
#77225 - 01/20/05 11:14 AM Re: You might think I'm crazy, but I'm not...
LT61 Offline
aficionado

Registered: 02/23/04
Posts: 836
Loc: Illinois.
MIKE,

For the record, I never said...."engineers shoot themselves in the foot"
My main point was this: It's too bad for every step forward in improving technology, products , etc., MOST companies take a couple steps, back when they see how cheaply they can produce their products, cutting too many corners, often times negating the leaps forward.

LT
_________________________
LIFE: "Choices, balance, and timing"

(Larryism)

Top
#77226 - 01/20/05 12:24 PM Re: You might think I'm crazy, but I'm not...
Misfit_Toy Offline
devotee

Registered: 02/22/04
Posts: 346
Loc: Wisconsin, USA
Yes, this goes along with the unfortunate truth of whenever I've "dug" for information from a company be it Harman Kardon, Yamaha or whoever they always tell me that they'll need to get that information to a technician. And guess what...you never hear back from them. Apparently it's all a big secret...the less we know the happier they seem to be.

I'm still waiting to hear from H/K...that was about a year ago
_________________________
"We're on the island of Misfit Toys"

Top
#77227 - 01/20/05 12:36 PM Re: You might think I'm crazy, but I'm not...
Ned Offline
veteran

Registered: 12/06/04
Posts: 117
Loc: Indianapolis, IN
Thanks for pointing out the Article Ajax...there is all kinds of that stuff over at Audioholics Forum.

John K ...I have heard the same about electricity flowing around the conductor like a monorail not through it like water flowing through a garden hose

_________________________
Axiom Denon Paradigm SVS

Top
#77228 - 01/20/05 02:30 PM Re: You might think I'm crazy, but I'm not...
biggsly5000 Offline
local

Registered: 11/30/04
Posts: 205
Loc: Atascocita, TX
I have asked Harman Kardon several questions and they did reply, in about a week. After a couple of days I had given up on them.

I worry more about having so many amplifiers connected to the same circuit than I do about the quality of my power chord. I have the receiver with its built in amps (although it is not connected to the speakers, so its current draw should be minimum), the seperate 5 channel 150 watts per channel power amplifier, and the SVS sub with 900 Watts. I realize they are not always putting out those peak numbers and that they do store some power internally for louder passages in movies/music, but still seems like a lot to me. There is also the 32" TV, the DVD player and th Cable box connected as well. I think dedicated circuits/outlets for the amplifiers would be a better upgrade than power chords.

In some passages of movies ie, LOTR the first one, when they are showing the battle scene in the beginning, and they cut the ring from whats his name's (Mordor?) finger the lights do dim in the living room. I still have not watched that movie all the way through yet and I have tried 3 times. I have not even tried to watch the other 2 yet. Seems like the sub is asking for a little too much power. I sometimes wonder if this could damage the amplifier. Or maybe the low bass is just vibrating the light bulb and making it a little dimmer? Who knows.

All of this equipment is on the same outlet, except for the sub, but I believe they are still on the same circuit anyway.

Some day I am just going to have to build a new house with a real dedicated HT room. I am thinking dedicated circuits/outlets, beefy wiring, surge protection at the fuse box, soundproofing etc. Only 29 more years to pay off the house I am in now....
_________________________
M80ti's, VP150, QS8's

Top
#77229 - 01/21/05 12:07 AM Re: You might think I'm crazy, but I'm not...
Michael_A Offline
devotee

Registered: 02/07/04
Posts: 418
In reply to:

Is induced currents a bad thing concerning speaker cables?



Yes. It is unwanted current flow that will go through your speakers, and come out as noise, and NO speaker wires (and the signals inside of them) are rarely, if ever the CAUSE of induced voltage.

I think you asked something other than you meant, though.

The audio signals flowing through the speaker wires are very small. They also do not repeat the same cycles over and over again, so any magnetic fields and the voltage created by them created by them will be very random, very small, and will not result in a steady flow.

A 120 volt AC signal is really 169 volts when you measure the sine wave from peak to peak. The 120 volts is RMS, or Root Mean Square. This is the measurement used for any time varying signal's effective value: It is not an "Average" voltage and its mathematical relationship to peak voltage varies depending on the type of waveform. By definition, RMS Value, also called the effective or "heating" value of AC, is equivalent to a DC voltage that would provide the same amount of heat generation in a resistor as the AC voltage would if applied to that same resistor.

This 169 volt AC signal goes from 0 volts to just about 85 volts and back to 0 volts in the first 1/2 cycle, and then it goes down to -85 volts and back up to 0 volts in the next 1/2 cycle. It does this 60 times per second. Each time the voltage goes up, a small magnetic field builds up around the power cord. As the voltage goes down, the magnetic field collapses again. Then the signal goes to the negative side, and a magnetic field builds up with the lines of force going around the power cord in the opposite direction. As the voltage goes back up to 0 volts again, that field collapses, and the cycle repeats. Inside of that power cord, there is NO induced voltage. The up and down swing of the voltage matches the polarity swing of the magnetic fields building up and collapsing ( "fluxing" for you "Back To The Future" fans ). They tend to cancel each other out.

So how does this affect audio? It doesn't. UNLESS you lay your speaker wire inside of the magnetic field that is always building up and collapsing around the power cord. Why? That speaker wire is supposed to contain 100% pure audio signal. If you lay the speaker wire ALONG SIDE OF your power cord, those magnetic fields also surround the speaker wire. As those fields build up and collapse, they move the electrons in the speaker wire causing the unwanted current to show up as a 60HZ buzz coming out of your speakers when no music is playing. When music IS playing, these voltages can just plain out mess with the audio signals in the speaker wires by adding and subtracting voltage from the audio signal.

There are 3 ways to avoid this.

#1 - always run you speaker wires across, but not next to your power cords. This way, the magnetic lines only "cut" into the speaker wire at a very small section, and they also do it perpedicular to the wire instead of parallel to it so no current is induced. (Any car buffs out there know that this also applies to spark plug wires as well for the exact same reason.)

#2 - Twist up the wire inside of the power cord, which "randomizes" the directions at which the fields are created (think helix). Doing so creates many small fields in many directions, and prevents them from causing any induced voltages large enough to matter.

#3 - Keep the speaker wires and power cords at least 6" apart - far enough to keep the magnetic fields away from the speaker wires altogether.

Oddly enough, it is the exact opposite use of magnetic fields that make the speakers work in the fist place, so go figure... Too much of a good thing, no?

_________________________
M- M60s/VP150/QS8s/SVS PC-Ultra/HK630 Sit down. Shut up. Listen.

Top
#77230 - 01/21/05 12:10 AM Re: You might think I'm crazy, but I'm not...
Michael_A Offline
devotee

Registered: 02/07/04
Posts: 418
I apologize Larry. I must have quoted someone else and gave you credit by mistake.
_________________________
M- M60s/VP150/QS8s/SVS PC-Ultra/HK630 Sit down. Shut up. Listen.

Top
#77231 - 01/21/05 07:28 AM Re: You might think I'm crazy, but I'm not...
MarkSJohnson Offline
shareholder in the making

Registered: 09/27/04
Posts: 10832
Loc: Central NH
Wow. This guy is smart.

I'm standing next to him.
_________________________
::::::: No disrespect to Axiom, but my favorite woofer is my yellow lab :::::::

Top
#77232 - 01/21/05 09:40 AM Re: You might think I'm crazy, but I'm not...
Misfit_Toy Offline
devotee

Registered: 02/22/04
Posts: 346
Loc: Wisconsin, USA
Hilarious.

Yes...a credit to you Michael_A. I've learning more now then I ever did in school
_________________________
"We're on the island of Misfit Toys"

Top
Page 7 of 8 < 1 2 3 4 5 6 7 8 >



Moderator:  alan, Amie, Andrew, axiomadmin, Brent, Debbie, Ian, Jc 

Home  |  Corporate Info  |  Products  |  Message Board  |  FAQs  |  Warranty  |  Site Map  |  Privacy Statement   |  Contact Us

©2014 Colquhoun Audio Laboratories Limited
All Rights Reserved.