in laymans terms , how ? meaning what ? what does such a statement , when correct , mean to ones ears ?? what difference does this control make ?
ta..
ta..
a more powerful amp has better control of the speakers ...
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The sound is created by the movement of the drive unit(s). If this movement isn't controlled then the resultant sound isn't accurate. If the drive unit(s) are under complete control then you will be getting the best resolution and reproduction from the amp and speakers in hand.
Where you lack control you add distortion and colourations to the sound, i.e. deviation from the original recording. More commonly (or easy to notice) is bass colouration. When the music demands a lot of bass, perhaps a bass peak, the speaker drive units will draw more current (especially so if there's a low impedance drop at certain frequencies). When this happens and the amp doesn't have the optimal amount of power available, you lack control and the bass sounds woolier, warmer and sometimes greater in magnitude. Sometimes it booms.
It's important to note that Watts isn't enough data about power availability. There's the balance between the amount of voltage and current available. Greater voltages will support greater volume, useful for insensitive speakers. Greater current delivery supports the control of a drive unit, moreso if the impedance curve is demanding and draws more current at certain frequencies. Think how some speakers state their nominal impedance at 8Ohms but they can dip to 3Ohms. That's enough to make the budget amp overheat and keel over! My speakers only dip to c.6Ohms and have an benign impedance curve so I don't need a lot of current to keep them in control. They're insensitive at c.83dB W so they need voltage to get going, lots of Watts!
It's actually even more complicated than that. There's the damping factor to consider too, the relationship between amplifier output impedance and the speaker's drive unit impedance. I don't understand this one very well but from what I understand, it's a non-issue unless you're dealing with flea-powered valve amps. For this concept, imagine if a speaker demands a 'wodge' of power but the amp's power supply simply can't find it quickly enough, the result is not ideal.
Where you lack control you add distortion and colourations to the sound, i.e. deviation from the original recording. More commonly (or easy to notice) is bass colouration. When the music demands a lot of bass, perhaps a bass peak, the speaker drive units will draw more current (especially so if there's a low impedance drop at certain frequencies). When this happens and the amp doesn't have the optimal amount of power available, you lack control and the bass sounds woolier, warmer and sometimes greater in magnitude. Sometimes it booms.
It's important to note that Watts isn't enough data about power availability. There's the balance between the amount of voltage and current available. Greater voltages will support greater volume, useful for insensitive speakers. Greater current delivery supports the control of a drive unit, moreso if the impedance curve is demanding and draws more current at certain frequencies. Think how some speakers state their nominal impedance at 8Ohms but they can dip to 3Ohms. That's enough to make the budget amp overheat and keel over! My speakers only dip to c.6Ohms and have an benign impedance curve so I don't need a lot of current to keep them in control. They're insensitive at c.83dB W so they need voltage to get going, lots of Watts!
It's actually even more complicated than that. There's the damping factor to consider too, the relationship between amplifier output impedance and the speaker's drive unit impedance. I don't understand this one very well but from what I understand, it's a non-issue unless you're dealing with flea-powered valve amps. For this concept, imagine if a speaker demands a 'wodge' of power but the amp's power supply simply can't find it quickly enough, the result is not ideal.
thanks igglebert , very thorough answer , so , in my case with my 45 watt marantz , and rx6s which i believe are easy to drive , using a more powerful amp like a kandy k2 , may not bring the control aspect into play as much as if i was using more demanding , harder to drive speakers ? like atc scm11 for example ??
maxflinn:thanks igglebert , very thorough answer , so , in my case with my 45 watt marantz , and rx6s which i believe are easy to drive , using a more powerful amp like a kandy k2 , may not bring the control aspect into play as much as if i was using more demanding , harder to drive speakers ? like atc scm11 for example ??
I don't know anything about the impedance characteristics of the RX6s nor SCM11s, and I don't know anything about the Marantz so I'm not sure!
My understanding was that the ATCs are very insensitive but not necessarily a difficult load. Thus, you don't need an amp that can start a car. If the RX6s are anything like the RS6s, they'll benefit from some current grunt to keep the bass under control. My opinion of MA speakers has always been that they boom a bit so more control is better in my books!
There's a lot to be gained from a better amp than the Marantz. It's not just about Watts to give volume and control (power amp duties) but's the detail and transparency is important too (pre amp duties). With a better amp like the K2 you should get more of everything. I'm rather fond of the K2 as I think it has a lovely tonal balance but you might not like it. Why not hunt out a Moon of some sort? Apparently very good!
EDIT I happen to think that the Quad offerings are very good for the cash and give a good balance of power and delicacy. They have their shortcomings too though!
I don't know anything about the impedance characteristics of the RX6s nor SCM11s, and I don't know anything about the Marantz so I'm not sure!
My understanding was that the ATCs are very insensitive but not necessarily a difficult load. Thus, you don't need an amp that can start a car. If the RX6s are anything like the RS6s, they'll benefit from some current grunt to keep the bass under control. My opinion of MA speakers has always been that they boom a bit so more control is better in my books!
There's a lot to be gained from a better amp than the Marantz. It's not just about Watts to give volume and control (power amp duties) but's the detail and transparency is important too (pre amp duties). With a better amp like the K2 you should get more of everything. I'm rather fond of the K2 as I think it has a lovely tonal balance but you might not like it. Why not hunt out a Moon of some sort? Apparently very good!
EDIT I happen to think that the Quad offerings are very good for the cash and give a good balance of power and delicacy. They have their shortcomings too though!
Bloody hell Rob, I didn't realise you were a rocket surgeon.
Maybe you can come round to work out why one of my lightbulbs has blown?
Maybe you can come round to work out why one of my lightbulbs has blown?
well im buying from munstersounds , ive bought all my kit there so far , and hes been very fair with prices and has allowed me to swap/trade in various items when i asked , hes giving me 90% of my 6003s sale price as a trade , plus i feel sure he will look after me should anything malfunction ..
the amps in the frame are the kandy k2 , marantz 8003 , exposure 2010 , and a few cyrus amps , which ill demo with my own speakers , the kandy just stands out on paper , 125 watts , and very good reviews , also its said to pair well with most speakers , to be honest i want to like it ..
hence this thread , im trying to understand what the extra power , apparent control may give me , aswell as the apparent extra quality all round that the roksan seemingly has
the amps in the frame are the kandy k2 , marantz 8003 , exposure 2010 , and a few cyrus amps , which ill demo with my own speakers , the kandy just stands out on paper , 125 watts , and very good reviews , also its said to pair well with most speakers , to be honest i want to like it ..
hence this thread , im trying to understand what the extra power , apparent control may give me , aswell as the apparent extra quality all round that the roksan seemingly has
what igg said.
and if it's ok to quote wiki: "Speaker diaphragms have mass, and their surrounds have stiffness. Together, these form a resonant system, and the mechanical cone resonance may be excited by electrical signals (e.g., pulses) at audio frequencies. But a driver with a voice coil
is also a current generator, since it has a coil attached to the cone
and suspension, and that coil is immersed in a magnetic field. For every
motion the coil makes, it will generate a current that will be seen by
any electrically attached equipment, such as an amplifier. In fact, the
amp's output circuitry will be the main electrical load on the "voice
coil current generator". If that load has low resistance, the current
will be larger and the voice coil will be more strongly forced to
decelerate. A high damping factor (which requires low output impedance
at the amplifier output) very rapidly damps unwanted cone movements
induced by the mechanical resonance of the speaker, acting as the
equivalent of a "brake" on the voice coil motion (just as a short
circuit across the terminals of a rotary electrical generator will make
it very hard to turn). It is generally (though not universally) thought
that tighter control of voice coil motion is desirable, as it is
believed to contribute to better-quality sound."
and if it's ok to quote wiki: "Speaker diaphragms have mass, and their surrounds have stiffness. Together, these form a resonant system, and the mechanical cone resonance may be excited by electrical signals (e.g., pulses) at audio frequencies. But a driver with a voice coil
is also a current generator, since it has a coil attached to the cone
and suspension, and that coil is immersed in a magnetic field. For every
motion the coil makes, it will generate a current that will be seen by
any electrically attached equipment, such as an amplifier. In fact, the
amp's output circuitry will be the main electrical load on the "voice
coil current generator". If that load has low resistance, the current
will be larger and the voice coil will be more strongly forced to
decelerate. A high damping factor (which requires low output impedance
at the amplifier output) very rapidly damps unwanted cone movements
induced by the mechanical resonance of the speaker, acting as the
equivalent of a "brake" on the voice coil motion (just as a short
circuit across the terminals of a rotary electrical generator will make
it very hard to turn). It is generally (though not universally) thought
that tighter control of voice coil motion is desirable, as it is
believed to contribute to better-quality sound."
JoelSim:
Bloody hell Rob, I didn't realise you were a rocket surgeon.
Maybe you can come round to work out why one of my lightbulbs has blown?
...the Leema drawing masses of current from the grid?
Bloody hell Rob, I didn't realise you were a rocket surgeon.
Maybe you can come round to work out why one of my lightbulbs has blown?
...the Leema drawing masses of current from the grid?
as i understand it, damping factor relates to the amps ability to stop the speaker cone, as it moves in and out, in the correct place and return it to it's starting point, ready for the next bass note. should give a tighter, more accurate sound. it's alright having a shed load of power to get the cone moving, but it needs to stop when it's told as well.
I think you're right Craig. Somehow this relates to amp output impedance (as per the power supply) and the speaker impedance. Beyond that I'm still trying to understand it. Not sure why though lol
yes, i spent a couple of hours reading up on it and trying to work it out, that's time i won't get back... still, if max has learnt something, even if only that i need to get out more, then it was all worth it.
Craig M.:yes, i spent a couple of hours reading up on it and trying to work it out, that's time i won't get back... still, if max has learnt something, even if only that i need to get out more, then it was all worth it.
ah your a goodun craig
.. i have learned something , i want the more powerful kandy even more now
...
i reckon daveh knows my next move
................
ah your a goodun craig
i reckon daveh knows my next move
igglebert:JoelSim:
Bloody hell Rob, I didn't realise you were a rocket surgeon.
Maybe you can come round to work out why one of my lightbulbs has blown?
...the Leema drawing masses of current from the grid?
I doubt that given the volume that is allowed by swmbo.
Bloody hell Rob, I didn't realise you were a rocket surgeon.
Maybe you can come round to work out why one of my lightbulbs has blown?
...the Leema drawing masses of current from the grid?
I doubt that given the volume that is allowed by swmbo.
JamesOK
Well-known member
igglebert:The sound is created by the movement of the drive unit(s). If this movement isn't controlled then the resultant sound isn't accurate. If the drive unit(s) are under complete control then you will be getting the best resolution and reproduction from the amp and speakers in hand.
Where you lack control you add distortion and colourations to the sound, i.e. deviation from the original recording. More commonly (or easy to notice) is bass colouration. When the music demands a lot of bass, perhaps a bass peak, the speaker drive units will draw more current (especially so if there's a low impedance drop at certain frequencies). When this happens and the amp doesn't have the optimal amount of power available, you lack control and the bass sounds woolier, warmer and sometimes greater in magnitude. Sometimes it booms.
It's important to note that Watts isn't enough data about power availability. There's the balance between the amount of voltage and current available. Greater voltages will support greater volume, useful for insensitive speakers. Greater current delivery supports the control of a drive unit, moreso if the impedance curve is demanding and draws more current at certain frequencies. Think how some speakers state their nominal impedance at 8Ohms but they can dip to 3Ohms. That's enough to make the budget amp overheat and keel over! My speakers only dip to c.6Ohms and have an benign impedance curve so I don't need a lot of current to keep them in control. They're insensitive at c.83dB W so they need voltage to get going, lots of Watts!
It's actually even more complicated than that. There's the damping factor to consider too, the relationship between amplifier output impedance and the speaker's drive unit impedance. I don't understand this one very well but from what I understand, it's a non-issue unless you're dealing with flea-powered valve amps. For this concept, imagine if a speaker demands a 'wodge' of power but the amp's power supply simply can't find it quickly enough, the result is not ideal.
Thanks IB - one of the best few paragraphs I have read on the forums for ages. I actually did A Level electronics about 15 ish years ago, I wish I could remember some of it. May come in useful in the hifi field...
Where you lack control you add distortion and colourations to the sound, i.e. deviation from the original recording. More commonly (or easy to notice) is bass colouration. When the music demands a lot of bass, perhaps a bass peak, the speaker drive units will draw more current (especially so if there's a low impedance drop at certain frequencies). When this happens and the amp doesn't have the optimal amount of power available, you lack control and the bass sounds woolier, warmer and sometimes greater in magnitude. Sometimes it booms.
It's important to note that Watts isn't enough data about power availability. There's the balance between the amount of voltage and current available. Greater voltages will support greater volume, useful for insensitive speakers. Greater current delivery supports the control of a drive unit, moreso if the impedance curve is demanding and draws more current at certain frequencies. Think how some speakers state their nominal impedance at 8Ohms but they can dip to 3Ohms. That's enough to make the budget amp overheat and keel over! My speakers only dip to c.6Ohms and have an benign impedance curve so I don't need a lot of current to keep them in control. They're insensitive at c.83dB W so they need voltage to get going, lots of Watts!
It's actually even more complicated than that. There's the damping factor to consider too, the relationship between amplifier output impedance and the speaker's drive unit impedance. I don't understand this one very well but from what I understand, it's a non-issue unless you're dealing with flea-powered valve amps. For this concept, imagine if a speaker demands a 'wodge' of power but the amp's power supply simply can't find it quickly enough, the result is not ideal.
Thanks IB - one of the best few paragraphs I have read on the forums for ages. I actually did A Level electronics about 15 ish years ago, I wish I could remember some of it. May come in useful in the hifi field...
On the topic of damping factors...
From Wikipedia
"Damping factor describes the ability of the amplifier to control unintended movement of the speaker cone near the resonant frequency of the driver. Other things being equal, a high damping factor indicates that an amplifier will have greater control over the movement of the driver cone, particularly in the bass region near the resonant frequency of the driver."
This is simply the ratio of the speaker impedance to the driving impedance, so an amplifier having an output impedance of 0.5 ohms driving an 8 ohm drive unit will have a damping factor of 16. Higher values are usually considered better (although Wikipedia has something to say about this...)
One thing to bear in mind is that in typical speaker systems (not active), there is a crossover between the amplifier and the drive unit.
Taking my system as an example, Roksan quote a damping factor of 400 into 8Ohms for my Caspian mono, however the impedance of my Monitor Audo PL100s ranges from under 4Ohms at 50Hz and 200Hz to around 28 Ohms at 2KHz, with various peaks and troughs in between. As you'll be able to work out from this, the damping factor is going to vary considerably with frequency.
For those interested, there's a good article on Wikipedia if you search for "Audio Crossover".
From Wikipedia
"Damping factor describes the ability of the amplifier to control unintended movement of the speaker cone near the resonant frequency of the driver. Other things being equal, a high damping factor indicates that an amplifier will have greater control over the movement of the driver cone, particularly in the bass region near the resonant frequency of the driver."
This is simply the ratio of the speaker impedance to the driving impedance, so an amplifier having an output impedance of 0.5 ohms driving an 8 ohm drive unit will have a damping factor of 16. Higher values are usually considered better (although Wikipedia has something to say about this...)
One thing to bear in mind is that in typical speaker systems (not active), there is a crossover between the amplifier and the drive unit.
Taking my system as an example, Roksan quote a damping factor of 400 into 8Ohms for my Caspian mono, however the impedance of my Monitor Audo PL100s ranges from under 4Ohms at 50Hz and 200Hz to around 28 Ohms at 2KHz, with various peaks and troughs in between. As you'll be able to work out from this, the damping factor is going to vary considerably with frequency.
For those interested, there's a good article on Wikipedia if you search for "Audio Crossover".
So back to the original question, i.e., whether a more powerful amp has better control of the speakers.
Damping factor is a product of output impedance of the amplifier and the load presented by the speakers, not amplifier power output.
However, a more powerful amplifier is less likely to clip. When an amplifier is pushed to create a signal with more power than its power supply can produce, it will amplify the signal only up to its maximum capacity, at which point the signal can be amplified no further. As the signal simply "cuts" or "clips" at the maximum capacity of the amplifier, the signal is said to be "clipping". The extra signal which is beyond the capability of the amplifier is simply cut off, resulting in a sine wave becoming a distorted square-wave-type waveform.
The amount of power required for reasonable listening levels is a hotly debated topic, resulting in amplifiers as varied as Musical Fidelity's 1000 watt Titan and valve amplifiers with just a few watts.
Damping factor is a product of output impedance of the amplifier and the load presented by the speakers, not amplifier power output.
However, a more powerful amplifier is less likely to clip. When an amplifier is pushed to create a signal with more power than its power supply can produce, it will amplify the signal only up to its maximum capacity, at which point the signal can be amplified no further. As the signal simply "cuts" or "clips" at the maximum capacity of the amplifier, the signal is said to be "clipping". The extra signal which is beyond the capability of the amplifier is simply cut off, resulting in a sine wave becoming a distorted square-wave-type waveform.
The amount of power required for reasonable listening levels is a hotly debated topic, resulting in amplifiers as varied as Musical Fidelity's 1000 watt Titan and valve amplifiers with just a few watts.
SteveR750
Well-known member
Craig M.:as i understand it, damping factor relates to the amps ability to stop the speaker cone, as it moves in and out, in the correct place and return it to it's starting point, ready for the next bass note. should give a tighter, more accurate sound. it's alright having a shed load of power to get the cone moving, but it needs to stop when it's told as well.
It's a way of measuring the back EMF that the coil "sees". It's relevance is not that clear someone posted a link a while ago to some tech research done back in the 60s (BBC?) that showed the effects of varying damping factor. However, this was just using single frequency square wave signals, which unless you like German electronica is far removed from typical music.
The key thing about a more powerful amp is the ability to provide more current at frequencies where the speaker impedance dips. As you turn the volume up, the output voltage increases, which when viewed on a 'scope can be seen as higher peaks and troughs of the sond wave. The speaker cone should follow these peaks and troughs in a linear fashion to the applied voltage. At a given loudness (voltage), in order to push or pull the cone to the correct position in space requires current (simple EMF effect), and the amount of current required is dependant on the impedance of the circuit. If the impedance dips (and its usually around the crossover frequencies), then the amp needs to provide more current to maintain the correct cone movement. In theory, the current should double if the impedance halves (and since we are at a fixed volume, i.e. voltage, then it is aso true that half the impedance = twice the power). Not many amps, even good ones achieve this even as a dynamic transient. NAD amps are some of the few that are capable of delivering double power into a halving of the impedance load. Interestingly, from the specs, the K2 isn't. However, it is plenty loud enough to my ears o as ever specs are only a small part of the consideration. Ultimately, since hi fi is a device for listening to, then its what your ears preceive that matters, not what the lab tests show.
It's a way of measuring the back EMF that the coil "sees". It's relevance is not that clear someone posted a link a while ago to some tech research done back in the 60s (BBC?) that showed the effects of varying damping factor. However, this was just using single frequency square wave signals, which unless you like German electronica is far removed from typical music.
The key thing about a more powerful amp is the ability to provide more current at frequencies where the speaker impedance dips. As you turn the volume up, the output voltage increases, which when viewed on a 'scope can be seen as higher peaks and troughs of the sond wave. The speaker cone should follow these peaks and troughs in a linear fashion to the applied voltage. At a given loudness (voltage), in order to push or pull the cone to the correct position in space requires current (simple EMF effect), and the amount of current required is dependant on the impedance of the circuit. If the impedance dips (and its usually around the crossover frequencies), then the amp needs to provide more current to maintain the correct cone movement. In theory, the current should double if the impedance halves (and since we are at a fixed volume, i.e. voltage, then it is aso true that half the impedance = twice the power). Not many amps, even good ones achieve this even as a dynamic transient. NAD amps are some of the few that are capable of delivering double power into a halving of the impedance load. Interestingly, from the specs, the K2 isn't. However, it is plenty loud enough to my ears o as ever specs are only a small part of the consideration. Ultimately, since hi fi is a device for listening to, then its what your ears preceive that matters, not what the lab tests show.
Steve, WinterRacer, some good explanations there. I guess that this basic knowledge is useful to get an idea of amp and speaker matching, but your ears are still going to make the decision.
You're welcome James. I've no doubt you know far more about the field than me! I was never any good at the maths else I'd have been an eng!
maxflinn:thanks igglebert , very thorough answer , so , in my case with my 45 watt marantz , and rx6s which i believe are easy to drive , using a more powerful amp like a kandy k2 , may not bring the control aspect into play as much as if i was using more demanding , harder to drive speakers ? like atc scm11 for example ??
I had some RS6 and K2 player/amp and other players at home. Sorry to say but it was softcentred with ill controlled bass. Something confirmed with subsequent listening in a different location. An Arcam A38 sorted things out, kind of.
As always, my opinion only.
I had some RS6 and K2 player/amp and other players at home. Sorry to say but it was softcentred with ill controlled bass. Something confirmed with subsequent listening in a different location. An Arcam A38 sorted things out, kind of.
As always, my opinion only.
SteveR750
Well-known member
WinterRacer:
So back to the original question, i.e., whether a more powerful amp has better control of the speakers.
Damping factor is a product of output impedance of the amplifier and the load presented by the speakers, not amplifier power output.
However, a more powerful amplifier is less likely to clip. When an amplifier is pushed to create a signal with more power than its power supply can produce, it will amplify the signal only up to its maximum capacity, at which point the signal can be amplified no further. As the signal simply "cuts" or "clips" at the maximum capacity of the amplifier, the signal is said to be "clipping". The extra signal which is beyond the capability of the amplifier is simply cut off, resulting in a sine wave becoming a distorted square-wave-type waveform.
The amount of power required for reasonable listening levels is a hotly debated topic, resulting in amplifiers as varied as Musical Fidelity's 1000 watt Titan and valve amplifiers with just a few watts.
Absolutely, and its worth adding that when an amp clips, the resulting waveform is very high voltage HF, which invariably melts the voice coil in your tweeter - the dreaded party speaker fry-up effect.
So back to the original question, i.e., whether a more powerful amp has better control of the speakers.
Damping factor is a product of output impedance of the amplifier and the load presented by the speakers, not amplifier power output.
However, a more powerful amplifier is less likely to clip. When an amplifier is pushed to create a signal with more power than its power supply can produce, it will amplify the signal only up to its maximum capacity, at which point the signal can be amplified no further. As the signal simply "cuts" or "clips" at the maximum capacity of the amplifier, the signal is said to be "clipping". The extra signal which is beyond the capability of the amplifier is simply cut off, resulting in a sine wave becoming a distorted square-wave-type waveform.
The amount of power required for reasonable listening levels is a hotly debated topic, resulting in amplifiers as varied as Musical Fidelity's 1000 watt Titan and valve amplifiers with just a few watts.
Absolutely, and its worth adding that when an amp clips, the resulting waveform is very high voltage HF, which invariably melts the voice coil in your tweeter - the dreaded party speaker fry-up effect.
drummerman:
maxflinn:thanks igglebert , very thorough answer , so , in my case with my 45 watt marantz , and rx6s which i believe are easy to drive , using a more powerful amp like a kandy k2 , may not bring the control aspect into play as much as if i was using more demanding , harder to drive speakers ? like atc scm11 for example ??
I had some RS6 and K2 player/amp and other players at home. Sorry to say but it was softcentred with ill controlled bass. Something confirmed with subsequent listening in a different location. An Arcam A38 sorted things out, kind of.
As always, my opinion only.
interesting , i think the bass im currently getting is very good , i wouldnt call it ill controlled , although ive only ever heard my own system , so its hard to know , anyway a shop demo while not ideal , should hopefully help ...
maxflinn:thanks igglebert , very thorough answer , so , in my case with my 45 watt marantz , and rx6s which i believe are easy to drive , using a more powerful amp like a kandy k2 , may not bring the control aspect into play as much as if i was using more demanding , harder to drive speakers ? like atc scm11 for example ??
I had some RS6 and K2 player/amp and other players at home. Sorry to say but it was softcentred with ill controlled bass. Something confirmed with subsequent listening in a different location. An Arcam A38 sorted things out, kind of.
As always, my opinion only.
interesting , i think the bass im currently getting is very good , i wouldnt call it ill controlled , although ive only ever heard my own system , so its hard to know , anyway a shop demo while not ideal , should hopefully help ...
Musical Fidelity will have you believe that you need a 500 watts amp to control your speakers, in my experience this wasn't the case! I had 25 watts class A, Vitus amp, driven ADAM speakers to very loud level and them drivers were totally under control of Vitus's current drive. My current 55 watts Mastersound will drive most speakers with ease and my friend's Tom Evan A power amp also got a total grip on his, hard to drive, B&W 802.
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