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Power handling!

Audiolab 6000A Amplifier

delhite2

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I have a question which popped in my head.
All things remaining same between 2 speakers.
Say
100 RMS,
30-25000 hz +/-3db,
90db sensitivity 2.83 volt,
All other specs same too.
The only difference is nominal impedance of 4ohm and 8ohms
One pair of speaker is rated at 4ohms. Other at 8 ohms.

Would the power handling differ between 2?
Lets say we are able to provide ideal power to both, will one a) sound better
B) play better
Or will it be same?
 

reachkalyan.kr

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I have a question which popped in my head.
All things remaining same between 2 speakers.
Say
100 RMS,
30-25000 hz +/-3db,
90db sensitivity 2.83 volt,
All other specs same too.
The only difference is nominal impedance of 4ohm and 8ohms
One pair of speaker is rated at 4ohms. Other at 8 ohms.

Would the power handling differ between 2?
Lets say we are able to provide ideal power to both, will one a) sound better
B) play better
Or will it be same?


similar kind of thread

https://www.hifivision.com/threads/...r-sound-than-8-ohm-speakers.34472/post-452882
 

reachkalyan.kr

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If you are planning for 4 -Ohm speaker.Make sure your system is capable to driving it
 

tuff

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My Magnepans are 4ohms super power hungry.4 ohms speakers require more current than a typical 6/8 ohms speaker. If the amp cannot deliver, the performance gets anemic.
 

delhite2

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True that! But will 2 pairs of otherwise identical speakers sound different just because of their nominal impedance differences when fed with ideal quality and quantity of power.
 

tuff

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True that! But will 2 pairs of otherwise identical speakers sound different just because of their nominal impedance differences when fed with ideal quality and quantity of power.
The difference for me for going from 150 watts at 4 ohms to 500 watts is huge especially in the lower bass region with the same amount of loudness in comparison. Hope that helps.
 

tuff

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Well also the Crown seems much more transparent than the Arcam power amp, with more detail and letting the Peachtree's pre-amp DAC do the magic.
 

delhite2

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The difference for me for going from 150 watts at 4 ohms to 500 watts is huge especially in the lower bass region with the same amount of loudness in comparison. Hope that helps.
I am glad you shared your insights, but the basic question is stil unanswered.
 

tuff

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I am glad you shared your insights, but the basic question is stil unanswered.
I frankly do not know if impedence of the same speaker will give you a different sound, as am not sure you can have a same speaker with different (4 or 8 ohm) impedance. But i am ignorant about that part.
 

Nikhil

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Nominal impedance usually represents the lowest impedance value a speaker goes down to.
Actual speaker impedance varies with frequency and is usually shown with an impedance curve.
When playing music impedance value depends on the frequency range being played.

See the Stereophile impedance plot for Dynaudio Excite X12 which is specified as a 4 ohm speaker

310Dynfig1.jpg



One pair of speaker is rated at 4ohms. Other at 8 ohms.

Would the power handling differ between 2?

The amp will need double the current (power) for the 4 ohm speaker.

Lets say we are able to provide ideal power to both, will one a) sound better
B) play better
Or will it be same?

A) Sound quality has nothing to do with impedance.

B) The 4 ohm speaker will be a more difficult load so all else being equal (as in your example) the 8 ohm will "play better"

Hope this helps ...


Regards.

.
 
Last edited:

delhite2

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Nominal impedance usually represents the lowest impedance value a speaker goes down to.
Actual speaker impedance varies with frequency and is usually shown with an impedance curve.
When playing music impedance value depends on the frequency range being played.

See the Stereophile impedance plot for Dynaudio Excite X12 which is specified as a 4 ohm speaker

310Dynfig1.jpg





The amp will need double the current (power) for the 4 ohm speaker.



A) Sound quality has nothing to do with impedance.

B) The 4 ohm speaker will be a more difficult load to the amp so all else being equal (as in your example) the 8 ohm will "play better"

Hope this helps ...


Regards.

.
And if ideal power is provided then they shall sound similar?
 

Nikhil

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And if ideal power is provided then they shall sound similar?

If you have an amp that drives a 4 ohm speaker it will drive a 8 ohm speaker with ease.

You will have more headroom so there will be some difference in sound.
But whether that is better depends on many different factors.

.
 
Last edited:

asliarun

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And if ideal power is provided then they shall sound similar?

You keep saying this again and again. But the reality is that this is almost never the case.
The reality is that amplifiers are almost always underpowered compared to the speaker.

Besides what Nikhil posted, the reality is also that speakers often provide an inductive load and not a resistive load. What does that mean? It means that the current often lags the voltage which in turn means that there will be times when the speaker is suddenly demanding huge amounts of current and power from the amp. And the amp has to respond in milliseconds.

So practical answer is that for most amps that people buy, a 4ohm speaker will end up sounding worse than an 8ohm speaker.
BUT if you have a real beefy amp, it will make your 4ohm speaker sing, and also the 4ohm speaker will likely be half the size of the 8ohm speaker and will still play much louder with cleaner and more authoritative bass.

Also, why are you asking this question in the first place? I'm only asking because it will help give you the correct answer.
Do you have two speakers in mind - one a 4 ohm and the other, a 8ohm? And which amp do you have in mind as well?
 

delhite2

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You keep saying this again and again. But the reality is that this is almost never the case.
The reality is that amplifiers are almost always underpowered compared to the speaker.

Besides what Nikhil posted, the reality is also that speakers often provide an inductive load and not a resistive load. What does that mean? It means that the current often lags the voltage which in turn means that there will be times when the speaker is suddenly demanding huge amounts of current and power from the amp. And the amp has to respond in milliseconds.

So practical answer is that for most amps that people buy, a 4ohm speaker will end up sounding worse than an 8ohm speaker.
BUT if you have a real beefy amp, it will make your 4ohm speaker sing, and also the 4ohm speaker will likely be half the size of the 8ohm speaker and will still play much louder with cleaner and more authoritative bass.

Also, why are you asking this question in the first place? I'm only asking because it will help give you the correct answer.
Do you have two speakers in mind - one a 4 ohm and the other, a 8ohm? And which amp do you have in mind as well?

I have nothing in mind, I asked because it just popped in my head while seeing the listing of some drivers of dayton which come in both 4ohm and 8ohm variations.
That's the only reason I asked, out of curiosity.
 

Kannan

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As has been mentioned by other members, the lower impedance speaker will draw more power and the amp should be capable of delivering it. All branded amps will always mention the minimum recommended impedance.

The other factor is THD (total harmonic distortion). With lower impedance speakers the comparative THD will be higher. Essentially, lower the THD better will be the output quality. So the amp design will matter here, how good THD values are as the impedance drops.

With power getting cheaper and the amplifier efficiency improving leap and bounds with Class D amps, high impedance and high sensitivity speakers of yore are getting out of vogue.
 
Last edited:

sashijoseph

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I have nothing in mind, I asked because it just popped in my head while seeing the listing of some drivers of dayton which come in both 4ohm and 8ohm variations.
That's the only reason I asked, out of curiosity.

If the amplifier is capable,both in terms of providing power and keeping distortion(at higher power outputs) in check,then the only apparent difference would be a louder 4 Ohm speaker at the same volume setting.
At the design level there would be some changes,especially in the crossover,when building a speaker box using these 4-Ohm/8-Ohm drivers. The TS parameters would be slightly different between the two(Voice coil inductance and Qes come to mind).
 
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