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11-15-2010, 12:53 AM
#21
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Quote:
Originally Posted by BradSk88
I suppose my mistake was trying to 'sell' cable improvements, rather than just pointing out that there are factors that make cable A better than cable B.
Sorry.
I'm also gonna retract the thing I said about pre-worn. I had a chat with some of the professors in my EE dept at university and they all agreed that while burn-in is a real thing, it only applies to dc current, because audio is AC it is random and burn-in wouldn't have any benefit.
__________________________________________________ _
Hi Brad
Like a dumb ***, I didn't fully read your comments - I read burn in and when to work...
With regards to speaker wire, you are still correct.
As mentioned, from time-to-time unwanted DC enters the AC network etc...
But within the AC domain, there is in fact much more going on because there are hundreds of thousands of tone transmitting through the cable. Each tome or frequency is affect differently by the cable, in that they each see a different resistance. In AC networks we don't use the work resistance or resistances we use impedance, which describes a single or average of resistances within a bandwidth of frequencies etc...
On we bring frequency (AC) in to the mix, we must also consider phase and with phase, cable capacitance and inductance. Better cables keep these potential swings or variances under tighter control, which is to say they are closer to being transparent. Please note that no cable is transparent and that’s where the wonderful world of Hi Fi, trial and error or audition comes into place.
Speaker cables have a profound effect on phase - which in my opinion is much more important than linear frequency response scores which are typically measured at low 1/3 per octave resolution...
The speaker cables also affect amplifier damping and passive cross-over performance...
Is speaker wire important - yes - but only in truly high-end home systems and not as much in noise automotive environments fed with iPods!
As for cable break-in - it is real as electrons flow from negative to positive and in this way the electrons become polarize or aligned with the direction of current flow, reducing resistances seen by each transmitted frequency...
Try this out - reverse your speaker wires in your system - it will sound different on wire lengths above 8' - try it and let us know what you find... Listen a few sounds before you the swap and then listen to the same songs afterwards...
If you would like a deeper understanding we could open another tread for the topic and talk a lot more about phase and speaker design as a whole...
Originally Posted by BradSk88
I suppose my mistake was trying to 'sell' cable improvements, rather than just pointing out that there are factors that make cable A better than cable B.
Sorry.
I'm also gonna retract the thing I said about pre-worn. I had a chat with some of the professors in my EE dept at university and they all agreed that while burn-in is a real thing, it only applies to dc current, because audio is AC it is random and burn-in wouldn't have any benefit.
__________________________________________________ _
Hi Brad
Like a dumb ***, I didn't fully read your comments - I read burn in and when to work...
With regards to speaker wire, you are still correct.
As mentioned, from time-to-time unwanted DC enters the AC network etc...
But within the AC domain, there is in fact much more going on because there are hundreds of thousands of tone transmitting through the cable. Each tome or frequency is affect differently by the cable, in that they each see a different resistance. In AC networks we don't use the work resistance or resistances we use impedance, which describes a single or average of resistances within a bandwidth of frequencies etc...
On we bring frequency (AC) in to the mix, we must also consider phase and with phase, cable capacitance and inductance. Better cables keep these potential swings or variances under tighter control, which is to say they are closer to being transparent. Please note that no cable is transparent and that’s where the wonderful world of Hi Fi, trial and error or audition comes into place.
Speaker cables have a profound effect on phase - which in my opinion is much more important than linear frequency response scores which are typically measured at low 1/3 per octave resolution...
The speaker cables also affect amplifier damping and passive cross-over performance...
Is speaker wire important - yes - but only in truly high-end home systems and not as much in noise automotive environments fed with iPods!
As for cable break-in - it is real as electrons flow from negative to positive and in this way the electrons become polarize or aligned with the direction of current flow, reducing resistances seen by each transmitted frequency...
Try this out - reverse your speaker wires in your system - it will sound different on wire lengths above 8' - try it and let us know what you find... Listen a few sounds before you the swap and then listen to the same songs afterwards...
If you would like a deeper understanding we could open another tread for the topic and talk a lot more about phase and speaker design as a whole...
Last edited by dogbaker; 11-15-2010 at 07:56 PM.
11-15-2010, 01:00 AM
#22
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Quote:
Originally Posted by AAAAAAA
wires affect phase? I need to see data backing this. But if the wire affects phase , then it should affect it equally from both sides thus making it a non-issue.
I don't know that I agree that phase is more important then FR. .. I mean if there is something wrong with the phase where will we see it?.... FR...no?
The whole speaker wire affecting damping factor is true, it is part of the "system damping factor" which is a non factor outside of concerts with very long runs of wire.
__________________________________________________ _______
Hello data is easy - do.
Frequency response and phase are bedfellows in that the useable frequency response is determined the the time arrival of sound that is why I cited basic 1/3 octave RTA analysis scores as weak evidence of objected goodness. I should have also mentioned TDS as being more useful as it determines frequency response by looking at the time arrival of each center frequency being measured. In this way, it allows us to know what is dire t sound or reflected sound - direct sound can be improved with EQs but reflections can not. Therefore TDS (time delay spectrometry) along side of FFT analysis is allowing us to see sound more accurately the in the past.
So on other words, amps have signal delay, preamplifiers have signal delays, speakers have signal delays, cd players have signal delays, rooms have signal delays - anything that opposes the pure transfer us energy creates a time smear and the goal of a quality system is to bring all of these signals together in time, both electrically and acoustically. The closer one gets the more transparent and accurate the musical reproduction will be. The next goal is to keep noise out both the electrical paths and acoustic space.
Forgive the typo - hammered this out on my iPhone
Originally Posted by AAAAAAA
wires affect phase? I need to see data backing this. But if the wire affects phase , then it should affect it equally from both sides thus making it a non-issue.
I don't know that I agree that phase is more important then FR. .. I mean if there is something wrong with the phase where will we see it?.... FR...no?
The whole speaker wire affecting damping factor is true, it is part of the "system damping factor" which is a non factor outside of concerts with very long runs of wire.
__________________________________________________ _______
Hello data is easy - do.
Frequency response and phase are bedfellows in that the useable frequency response is determined the the time arrival of sound that is why I cited basic 1/3 octave RTA analysis scores as weak evidence of objected goodness. I should have also mentioned TDS as being more useful as it determines frequency response by looking at the time arrival of each center frequency being measured. In this way, it allows us to know what is dire t sound or reflected sound - direct sound can be improved with EQs but reflections can not. Therefore TDS (time delay spectrometry) along side of FFT analysis is allowing us to see sound more accurately the in the past.
So on other words, amps have signal delay, preamplifiers have signal delays, speakers have signal delays, cd players have signal delays, rooms have signal delays - anything that opposes the pure transfer us energy creates a time smear and the goal of a quality system is to bring all of these signals together in time, both electrically and acoustically. The closer one gets the more transparent and accurate the musical reproduction will be. The next goal is to keep noise out both the electrical paths and acoustic space.
Forgive the typo - hammered this out on my iPhone
11-15-2010, 01:06 AM
#23
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Quote:
Originally Posted by dogbaker
Hello data is easy - do.
Frequency response and...<snip>
...hammered this out on my iPhone
__________________________________________________ _______
OK but how do speaker cables affect phase? Sorry to make you text it out again but I don't see how speaker cables were addressed.
Originally Posted by dogbaker
Hello data is easy - do.
Frequency response and...<snip>
...hammered this out on my iPhone
__________________________________________________ _______
OK but how do speaker cables affect phase? Sorry to make you text it out again but I don't see how speaker cables were addressed.
11-15-2010, 01:17 AM
#24
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Quote:
Originally Posted by kevmurray
OK but how do speaker cables affect phase? Sorry to make you text it out again but I don't see how speaker cables were addressed.
__________________________________________________ _______________
Hello
LOL - I was hoping that was enough, but here's a little more of the picture - electrons don't travel at a constant rate (speed = time = phase) in fact, the only type of energy transmission which has a constant (in a vacuum) is light - outside of a vacuum even light can be decayed etc... (if you want to understand this better just ask and I will shed some light on this as well).
All frequencies travel at different rates through cables and the cable itself is in fact a band-pass filter, decaying low and high frequencies and adding delays to some within the band-pass... the reason for this is that every cable has one order of capacitance, inductance and resistance... therefore phase variances are inherently present, basic fact in all such circuits!
There are other factors, the metals: copper vs. Aluminum, for example - energy travels faster through aluminum then it does copper - and aluminum has a completely different magnitude of inductance and capacitance qualities outside of the resistive differences, to that of copper (in fact copper cable vs. copper cable quality vary) etc... These factors affect frequency response and transparency and system Qtc plus-plus-plus...
There’s even more - cable loss and back-EMF, at high frequencies the cables jacket becomes very important (more so in highly resistive cables) as some of the high frequencies can actually leak out of the cable and at lengths over 8' back - EMF starts to become significant and audible and standing waves start (frequencies start to propagate from one-end of the cable to the other) adding or subtracting energy (at certain frequencies) that we as humans are very sensitive to...
There’s is still more, cable impurities - high frequencies are very sensitive to these and as a result the bass loses detail and the highs becoming bright and the sound stage often becomes underwhelming and inaccurate etc... Keep your cables the same length and cut from the same spool...
Do you need more - please understand that while resistance controls the quantity of electrons within a circuit, it also contributes to the rate at which the resulting electrons are passing: High resistance = lower electron count, but a faster velocity - couple this with capacitance, which is a current delaying component and we now have a slowing, but only at certain frequencies, so there is no constant... and the whole thing becomes very complex, but measurable...
When the electrical qualities of the cable are interconnected with a speaker and an amp, they all sum and output a specific frequency response, with their own unique group delay scores, impulse scores and global phase response scores – if we we’re then to change a single element and retake our objective measurements, all of the scores would changes as would the sound!
Each Sound system has a specific Qtc score at a specific input (Wattage) Qtc is a basic product of a weighted blend of group QMS and QES scores – the amp and cabling contribute to the QES scores and the speaker contributes to both – change anyone and the math changes and if the math changes the sound changes!
Order of greatest change – objective or subjective
1. Speaker
2. Pre-amp
3. Source
4. Amp
5. Cable
In a car, cables are long and have higher losses and the cables degrade faster... but the benefits are often lost or masked to road noise and other unwanted ingression acoustic signals... So in a car, keep the cables as short as possible, of high strand count, and of 99.999% pure oxygen free copper and 16 Gauge AWG! For subs use 12 Gauge... if you’re passing more than 30amps over 6’ use 10 or 8Gauge...
And by the way, there is still more!
If you have a degree in engineering - I will email you the math in a private email...
Originally Posted by kevmurray
OK but how do speaker cables affect phase? Sorry to make you text it out again but I don't see how speaker cables were addressed.
__________________________________________________ _______________
Hello
LOL - I was hoping that was enough, but here's a little more of the picture - electrons don't travel at a constant rate (speed = time = phase) in fact, the only type of energy transmission which has a constant (in a vacuum) is light - outside of a vacuum even light can be decayed etc... (if you want to understand this better just ask and I will shed some light on this as well).
All frequencies travel at different rates through cables and the cable itself is in fact a band-pass filter, decaying low and high frequencies and adding delays to some within the band-pass... the reason for this is that every cable has one order of capacitance, inductance and resistance... therefore phase variances are inherently present, basic fact in all such circuits!
There are other factors, the metals: copper vs. Aluminum, for example - energy travels faster through aluminum then it does copper - and aluminum has a completely different magnitude of inductance and capacitance qualities outside of the resistive differences, to that of copper (in fact copper cable vs. copper cable quality vary) etc... These factors affect frequency response and transparency and system Qtc plus-plus-plus...
There’s even more - cable loss and back-EMF, at high frequencies the cables jacket becomes very important (more so in highly resistive cables) as some of the high frequencies can actually leak out of the cable and at lengths over 8' back - EMF starts to become significant and audible and standing waves start (frequencies start to propagate from one-end of the cable to the other) adding or subtracting energy (at certain frequencies) that we as humans are very sensitive to...
There’s is still more, cable impurities - high frequencies are very sensitive to these and as a result the bass loses detail and the highs becoming bright and the sound stage often becomes underwhelming and inaccurate etc... Keep your cables the same length and cut from the same spool...
Do you need more - please understand that while resistance controls the quantity of electrons within a circuit, it also contributes to the rate at which the resulting electrons are passing: High resistance = lower electron count, but a faster velocity - couple this with capacitance, which is a current delaying component and we now have a slowing, but only at certain frequencies, so there is no constant... and the whole thing becomes very complex, but measurable...
When the electrical qualities of the cable are interconnected with a speaker and an amp, they all sum and output a specific frequency response, with their own unique group delay scores, impulse scores and global phase response scores – if we we’re then to change a single element and retake our objective measurements, all of the scores would changes as would the sound!
Each Sound system has a specific Qtc score at a specific input (Wattage) Qtc is a basic product of a weighted blend of group QMS and QES scores – the amp and cabling contribute to the QES scores and the speaker contributes to both – change anyone and the math changes and if the math changes the sound changes!
Order of greatest change – objective or subjective
1. Speaker
2. Pre-amp
3. Source
4. Amp
5. Cable
In a car, cables are long and have higher losses and the cables degrade faster... but the benefits are often lost or masked to road noise and other unwanted ingression acoustic signals... So in a car, keep the cables as short as possible, of high strand count, and of 99.999% pure oxygen free copper and 16 Gauge AWG! For subs use 12 Gauge... if you’re passing more than 30amps over 6’ use 10 or 8Gauge...
And by the way, there is still more!
If you have a degree in engineering - I will email you the math in a private email...
11-15-2010, 01:29 AM
#25
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Thread Starter
Join Date: Nov 2010
Posts: 230
Quote:
Originally Posted by Donnie
Oh boy.
I don't know where to start.
Where's that expert guy, maybe he can explain.
__________________________________________________ _____________
Electrons don't travel at or even near the speed of light - only photons do and only in a vacuum - outside of a vacuum photon are subject to massive decay.
The rate of electron flow is dictated by the material of the medium(s) of which it is passing through... mathematical fact!
Semi-conductors
Super-conductors
Pure Copper
Alloy
Steel
Aluminum
etc...
They all have different resistance - inductances and capacitances’... which affect the arrival time of the energies they are conducting...
Originally Posted by Donnie
Oh boy.
I don't know where to start.
Where's that expert guy, maybe he can explain.
__________________________________________________ _____________
Electrons don't travel at or even near the speed of light - only photons do and only in a vacuum - outside of a vacuum photon are subject to massive decay.
The rate of electron flow is dictated by the material of the medium(s) of which it is passing through... mathematical fact!
Semi-conductors
Super-conductors
Pure Copper
Alloy
Steel
Aluminum
etc...
They all have different resistance - inductances and capacitances’... which affect the arrival time of the energies they are conducting...
11-15-2010, 01:34 AM
#26
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Thread Starter
Join Date: Nov 2010
Posts: 230
Quote:
Originally Posted by Donnie
Oh boy.
I don't know where to start.
Where's that expert guy, maybe he can explain.
__________________________________________________ ___________
As well - as a point of fact human hearing is sensitive to the Pico scale...
Which explains why many of the tonal difference we hear between DA convertors.
Using a basic RTA they have looked flat but when we measure the phase response (using more sophisticated gear) we see that the rate at which many DA's process their bandwidths varies greatly...
Noting that CD players with DA's that have delays in the mid band (2-5K) in the Micro or range always sound bright while others with delays in the Nano range sounded smooth...etc...
It's in the phase... that we perceive most differences...
No electronic device produces its entire spectrum of sound within the same interval in time... one day they will but not for at least another 25-years or so... a good amp is a little slow from 20Hz - 200Hz and a above 18 KHz (2-10ms)... Speaker between 20Hz-100Hz regardless of enclosure type will have massive delays ranging from 100-500milliseconds, with the balance of the bandwidth roaming between 2-10ms, accept at the cross-over points, which were things get real messy in most designs... which why most people like active filters over pass, as they mitigate many of the phase issues (but not all).
Phase is the key and it is rooted in resistance and further complicated by inductance and capacitance...
The very best DA's have delay scores in the Pico range - but at 6k plus they should!
Weakest link speakers - all the way!
Originally Posted by Donnie
Oh boy.
I don't know where to start.
Where's that expert guy, maybe he can explain.
__________________________________________________ ___________
As well - as a point of fact human hearing is sensitive to the Pico scale...
Which explains why many of the tonal difference we hear between DA convertors.
Using a basic RTA they have looked flat but when we measure the phase response (using more sophisticated gear) we see that the rate at which many DA's process their bandwidths varies greatly...
Noting that CD players with DA's that have delays in the mid band (2-5K) in the Micro or range always sound bright while others with delays in the Nano range sounded smooth...etc...
It's in the phase... that we perceive most differences...
No electronic device produces its entire spectrum of sound within the same interval in time... one day they will but not for at least another 25-years or so... a good amp is a little slow from 20Hz - 200Hz and a above 18 KHz (2-10ms)... Speaker between 20Hz-100Hz regardless of enclosure type will have massive delays ranging from 100-500milliseconds, with the balance of the bandwidth roaming between 2-10ms, accept at the cross-over points, which were things get real messy in most designs... which why most people like active filters over pass, as they mitigate many of the phase issues (but not all).
Phase is the key and it is rooted in resistance and further complicated by inductance and capacitance...
The very best DA's have delay scores in the Pico range - but at 6k plus they should!
Weakest link speakers - all the way!
11-15-2010, 01:41 AM
#27
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Thread Starter
Join Date: Nov 2010
Posts: 230
Quote:
Originally Posted by Donnie
Why wouldn't I be serious?
You have a 30 foot garden hose and a 10 foot garden hose. You turn on the water supply to each at the same time. Do you think water will arrive at the end of each hose at the same time? Of course not! There's going to be a delay with the longer one.
Same principle applies with your speakers and their cables. Difference is we're talking extremely shorter delays than my garden hose example.
Moral of the story, use the same lengths of cable if you're running long, which in a car is a non-issue.
edit: looking through my books, I noted it there would need to be a difference of at least 100 feet of 12awg to notice anything
Originally Posted by Donnie
Why wouldn't I be serious?
You have a 30 foot garden hose and a 10 foot garden hose. You turn on the water supply to each at the same time. Do you think water will arrive at the end of each hose at the same time? Of course not! There's going to be a delay with the longer one.
Same principle applies with your speakers and their cables. Difference is we're talking extremely shorter delays than my garden hose example.
Moral of the story, use the same lengths of cable if you're running long, which in a car is a non-issue.
edit: looking through my books, I noted it there would need to be a difference of at least 100 feet of 12awg to notice anything
11-15-2010, 01:44 AM
#28
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Quote:
Originally Posted by kevmurray
It would have to be longer than that my friend.
__________________________________________________ ________
Well you are on the right path but there is more here to understand.
What about after the water makes it out the other side of each hose - is the rate the same then, once both of the capacitances have been satiated?
The answer is it depends on Pressure (Voltage), Resistance each hose.
The longer hose obviously has more capacitance (but once it’s full - it's full) and it's just as obvious that as there is also more surface area or drag, creating more resistance...
Assuming that same amount of water pressure remains constant for each hose and the hoses are identical other then in length - the water coming out of the longer hose will be exiting faster!
Think of your tap as a power supply or an amplifier – they are suppose to output a constant Voltage into a fixed load – if your water supply is able to supply them both with the same amount pressure into each of their fixed loads, the electrons/water will be traveling faster due to the higher resistance in the longer cable... basic algebra...
You want more proof - go turn on your garden hose and once a steady flow comes out the end - press your thumb against the flow - less water will pass (as evidenced by a swelling in the hose) but the water passing your thumb will be traveling faster...
That force can be viewed as Voltage - Voltage is a product of Resistance x the flow of Current (water) - the more resistance the more electrical pressure, pressure is perceivable as a force of mass (water/electrons) x velocity...
Originally Posted by kevmurray
It would have to be longer than that my friend.
__________________________________________________ ________
Well you are on the right path but there is more here to understand.
What about after the water makes it out the other side of each hose - is the rate the same then, once both of the capacitances have been satiated?
The answer is it depends on Pressure (Voltage), Resistance each hose.
The longer hose obviously has more capacitance (but once it’s full - it's full) and it's just as obvious that as there is also more surface area or drag, creating more resistance...
Assuming that same amount of water pressure remains constant for each hose and the hoses are identical other then in length - the water coming out of the longer hose will be exiting faster!
Think of your tap as a power supply or an amplifier – they are suppose to output a constant Voltage into a fixed load – if your water supply is able to supply them both with the same amount pressure into each of their fixed loads, the electrons/water will be traveling faster due to the higher resistance in the longer cable... basic algebra...
You want more proof - go turn on your garden hose and once a steady flow comes out the end - press your thumb against the flow - less water will pass (as evidenced by a swelling in the hose) but the water passing your thumb will be traveling faster...
That force can be viewed as Voltage - Voltage is a product of Resistance x the flow of Current (water) - the more resistance the more electrical pressure, pressure is perceivable as a force of mass (water/electrons) x velocity...
11-15-2010, 02:24 AM
#29
Apparently i have a poor grasp of english lol, but i do have a question for you.
Refering to a competition (spl) application, a "wall" style vented enclosure with woofers to the passenger side and vent to the driver side, I am trying to create a path for the rear sound wave to the vent with as little obstruction possible in efforts to closely maintain the spl from one side to the other of the enclosure....Hope your following me!!
I undestand ofcourse that as a wave travels further that it loses power and that as its reflected from surfaces that the same will occur so, how would "you design the interior of this cabinet "basic shape" for the purpose of sound pressure testing using only a single frequency??
Refering to a competition (spl) application, a "wall" style vented enclosure with woofers to the passenger side and vent to the driver side, I am trying to create a path for the rear sound wave to the vent with as little obstruction possible in efforts to closely maintain the spl from one side to the other of the enclosure....Hope your following me!!
I undestand ofcourse that as a wave travels further that it loses power and that as its reflected from surfaces that the same will occur so, how would "you design the interior of this cabinet "basic shape" for the purpose of sound pressure testing using only a single frequency??
11-15-2010, 02:26 AM
#30
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Join Date: Nov 2010
Posts: 230
wires affect phase? I need to see data backing this. But if the wire affects phase , then it should affect it equally from both sides thus making it a non-issue.
I don't know that I agree that phase is more important then FR. .. I mean if there is something wrong with the phase where will we see it?.... FR...no?
The whole speaker wire affecting damping factor is true, it is part of the "system damping factor" which is a non factor outside of concerts with very long runs of wire.
__________________________________________________ _____
I ran out of time to get back to this one tonight -
Not sure what is ment by both sides but if your driving at a loop and 180 degree phase shift which would cancel - that thinking has no place here as the speaker will have already received the signal...
Damping factor like phase is affected, but damping isn't as critical and is much easier to measure than the individual arrival times of frequencies etc...
I don't know that I agree that phase is more important then FR. .. I mean if there is something wrong with the phase where will we see it?.... FR...no?
The whole speaker wire affecting damping factor is true, it is part of the "system damping factor" which is a non factor outside of concerts with very long runs of wire.
__________________________________________________ _____
I ran out of time to get back to this one tonight -
Not sure what is ment by both sides but if your driving at a loop and 180 degree phase shift which would cancel - that thinking has no place here as the speaker will have already received the signal...
Damping factor like phase is affected, but damping isn't as critical and is much easier to measure than the individual arrival times of frequencies etc...
