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HD800 vs HE500 - Page 66

post #976 of 989
Quote:
Originally Posted by James-uk View Post


Hd800 need less than 300mW ? Why do you think 1000?

 

I think what he means is that without proper amplificaiton the HD800 will turn out bright and anoying.

 

300mW or 1000mW are just numbers and doesn't tell the whole story. The thing is however that if you find the right amp for the HD800 it can give you bass so deep and hard it makes your head shake! Not many know this... but a HD800 with the right amp and maybe a bit of EQ is really a bass lovers dream, and it won't be bright at all.

post #977 of 989
Quote:
Originally Posted by TwoEars View Post

I think what he means is that without proper amplificaiton the HD800 will turn out bright and anoying.

300mW or 1000mW are just numbers and doesn't tell the whole story. The thing is however that if you find the right amp for the HD800 it can give you bass so deep and hard it makes your head shake! Not many know this... but a HD800 with the right amp and maybe a bit of EQ is really a bass lovers dream, and it won't be bright at all.

Well they are not just numbers they are power ratings. If an amp can output 20,000mW the hd800 won't use them. It will still only use it's required amount because otherwise it will burst your eardrums. I'm sure the hd800 needs about 250mW to reach 120 db. No need for anymore than that. Am I missing something?
post #978 of 989

Yeah...hd800 isn't an ortho so i'd assume it doesn't benefit from current in the same way either?

post #979 of 989
Quote:
Originally Posted by James-uk View Post


Well they are not just numbers they are power ratings. If an amp can output 20,000mW the hd800 won't use them. It will still only use it's required amount because otherwise it will burst your eardrums. I'm sure the hd800 needs about 250mW to reach 120 db. No need for anymore than that. Am I missing something?

 

Maybe, look at this graph:

 

Many amps will drive those headphones but without the required *omph* to mitigate that impedance spike around 100 Hz they overall effect is that the headphone will turn out bright and the bass will be weak, flabby and uncontrolled.

 

With an amp that has plenty of muscles to spare that impedance spike won't matter. That's why we want a good sized amp so that it's powerful enough not to care about stupid things like a variable headphone impedance.

 

The other thing is that it's not only about how many watts you deliver, it's about how you deliver them and where.

post #980 of 989

the point is another IMO

 

I have a yaoin 300b with a resistor through the speaker output, and a dac1

 

from both the bass is more than enough with no brightness nor sibilance.

 

the problem is that i've been using this setup since i got my first hd800.

post #981 of 989
Quote:
Originally Posted by TwoEars View Post
 

 

Maybe, look at this graph:

 

Many amps will drive those headphones but without the required *omph* to mitigate that impedance spike around 100 Hz they overall effect is that the headphone will turn out bright and the bass will be weak, flabby and uncontrolled.

 

With an amp that has plenty of muscles to spare that impedance spike won't matter. That's why we want a good sized amp so that it's powerful enough not to care about stupid things like a variable headphone impedance.

 

The other thing is that it's not only about how many watts you deliver, it's about how you deliver them and where.

The impedance spike does not require more power, it requires less power. Amplifiers deliver voltage gain, so at the same volume, less power or current is required.

P = E2 / R 

Since the voltage (E) will not change but R (impedance) increases the required power or current actually decreases.

Problems only occur if the amp's output impedance is high, or if you have a series resistor, it will form a voltage divider with the impedance of the headphones. So as the impedance of the headphone increases the bass will increase but there will be a loss of damping so the qulaity of this increased bass will decrease.

For an HD800 driven by a low impedance amp, there will be no such issues. Add a 100 Ohms (perhaps larger) series resistor to the same amp and things will get ugly.

The HE-500 is a different type of headphone, it is considered resistive, and not having any reactance worth consideration in this scenario.

I'm curious, regarding watts, what did you mean by "it's about how you deliver them and where?"


Edited by StanD - 3/19/14 at 8:42pm
post #982 of 989
Quote:
Originally Posted by StanD View Post
 

The impedance spike does not require more power, it requires less power. Amplifiers deliver voltage gain, so at the same volume, less power or current is required.

P = E2 / R 

Since the voltage (E) will not change but R (impedance) increases the required power or current actually decreases.

Problems only occur if the amp's output impedance is high, or if you have a series resistor, it will form a voltage divider with the impedance of the headphones. So as the impedance of the headphone increases the bass will increase but there will be a loss of damping so the qulaity of this increased bass will decrease.

For an HD800 driven by a low impedance amp, there will be no such issues. Add a 100 Ohms (perhaps larger) series resistor to the same amp and things will get ugly.

The HE-500 is a different type of headphone, it is considered resistive, and not having any reactance worth consideration in this scenario.

I'm curious, regarding watts, what did you mean by "it's about how you deliver them and where?"

 

Ohm's law is of course correct but it's actually more complex than that in reality. The biggest factor is how well an amplifier deals with a varying load, cheaper amplifiers tend to have poor dampening characteristics and varying output impedance into different voltages.

 

What we want in order to drive something like the HD650's well is an amp that swing a lot of voltage and do it fast, cleanly and without clipping or distortion and without varying output impedance or dampening. That hump around 100 Hz is actually to some extent driver resonance, and what can happen if you have a smallish amp is that the headphone, to some extent, ends up driving the amp and not the other way around! The driver and the amp becomes one big resonating circuit. You definitely don't want that.

 

The sum of it all is that you want a "beefy" amp that does it's own thing and doesn't care about the headphone. You want the amp that has that "perfect cube" response and no variations in damping or output impedance.

 

The take away from it all is that headphones with a flat impedance curve (D7000) is relatively easy for most amps to drive well, but a headphone with a big variation in the impedance curve, like the HD650, requires a well thought out and manufactured amp to sound good.


Edited by TwoEars - 3/20/14 at 2:08am
post #983 of 989
Quote:
Originally Posted by TwoEars View Post
 

 

Ohm's law is of course correct but it's actually more complex than that in reality. The biggest factor is how well an amplifier deals with a varying load, cheaper amplifiers tend to have poor dampening characteristics and varying output impedance into different voltages.

 

What we want in order to drive something like the HD650's well is an amp that swing a lot of voltage and do it fast, cleanly and without clipping or distortion and without varying output impedance or dampening. That hump around 100 Hz is actually to some extent driver resonance, and what can happen if you have a smallish amp is that the headphone, to some extent, ends up driving the amp and not the other way around! The driver and the amp becomes one big resonating circuit. You definitely don't want that.

 

The sum of it all is that you want a "beefy" amp that does it's own thing and doesn't care about the headphone. You want the amp that has that "perfect cube" response and no variations in damping or output impedance.

 

The take away from it all is that headphones with a flat impedance curve (D7000) is relatively easy for most amps to drive well, but a headphone with a big variation in the impedance curve, like the HD650, requires a well thought out and manufactured amp to sound good.

You must be thinking of really bad amps. Most modern SS amps, even cheap ones have a low impedance that does not vary by much, especially Opamp types with feedback. Again impedance variation is not an issue with low impedance SS amps, especially when you hook up a 300 Ohm headphone to it. For a high impedance headphone you need an amp that can swing to higher voltages to satisfy their sensitivity, easy enough to find. Again the impedance curve is a problem when the amp's output impedance is high or a series resistor is in place. A high impedance headphone will not do anything to the low impedance amp, as the impedance increases the affect on the amp actually diminishes. There is no Hi Q resonant circuit here, period. A fast enough slew rate for audio frequencies is very easy to achieve these days,

By the way, Ohms law does not calculate power. Wattage is named after James Watt.

post #984 of 989
Quote:
Originally Posted by StanD View Post
 

You must be thinking of really bad amps. Most modern SS amps, even cheap ones have a low impedance that does not vary by much, especially Opamp types with feedback. Again impedance variation is not an issue with low impedance SS amps, especially when you hook up a 300 Ohm headphone to it. For a high impedance headphone you need an amp that can swing to higher voltages to satisfy their sensitivity, easy enough to find. Again the impedance curve is a problem when the amp's output impedance is high or a series resistor is in place. A high impedance headphone will not do anything to the low impedance amp, as the impedance increases the affect on the amp actually diminishes. There is no Hi Q resonant circuit here, period. A fast enough slew rate for audio frequencies is very easy to achieve these days,

By the way, Ohms law does not calculate power. Wattage is named after James Watt.

 

Sorry about Mr Watts there, my bad.

 

Also, please understand that I'm not arguing against you. I do agree with many of the things you are saying.... all we really want is an amp that can swing the desired voltage (and also supply the needed current) and do so cleanly and well, I'm all aboard on that one.

 

However... the point I'm trying make here goes back a little bit to as to why some amps have "slam and authority" while other seem "meek and mellow". The only reason I can personally think of as to why one amp has "slam and authority", while another hasn't, is that it has faster transient responses, less internal resistance and more current reserves.

 

As you know the audiophile press likes to call this having "headroom" or "muscles to spare". The mellower amp may be able to output +/-2 volts, which is more than enough to drive most headphones, but in doing so it may be close to its max operating limit and there may be slow transient responses, clipping or distortion. I mean - isn't the point of a high-end amp to move as far away from this as possible so that we're operating as linearly as possible no matter the varying impedance/resistance of the headphone?

 

If you have any other hidden insight into it is why some amps have "slam and authority" while others sound mellow feel free to speak up! I'm interested! :smile: 


Edited by TwoEars - 3/20/14 at 8:21am
post #985 of 989
Quote:
Originally Posted by TwoEars View Post
 

 

Sorry about Mr Watts there, my bad.

 

Also, please understand that I'm not arguing against you. I do agree with many of the things you are saying.... all we really want is an amp that can swing the desired voltage (and also supply the needed current) and do so cleanly and well, I'm all aboard on that one.

 

However... the point I'm trying make here goes back a little bit to as to why some amps have "slam and authority" while other seem "meek and mellow". The only reason I can personally think of as to why one amp has "slam and authority", while another hasn't, is that it has faster transient responses, less internal resistance and more current reserves.

 

As you know the audiophile press likes to call this having "headroom" or "muscles to spare". The mellower amp may be able to output +/-2 volts, which is more than enough to drive most headphones, but in doing so it may be close to its max operating limit and there may be slow transient responses, clipping or distortion. I mean - isn't the point of a high-end amp to move as far away from this as possible so that we're operating as linearly as possible no matter the varying impedance/resistance of the headphone?

 

If you have any other hidden insight into it is why some amps have "slam and authority" while others sound mellow feel free to speak up! I'm interested! :smile: 

Any power above the headroom + maximum listening level  that exceeds the dynamic range of your source does nothing for you.

Specs are a funny thing. One can measure noise against a 2V reference level instead of a 1V reference level and get a 6 dB inflation to their spec.  Or can measure distortion at a frequency and power level that yeilds good numbers whilst other frequencies or power levels are plain awful. Sometimes I think some guys just plain lie. Nobody seems to like specifying TIMD (Transient Intermodulation Distortion) which is nasty business. That's why the ears know. Unfortunately us humans are easily swayed and even fill in the blanks. Years ago my wife had a college GF who's hubby was a P.h.D. in Psych. His big thing was experimental psych and perception. He used to put wires into rats' brains and experiment on people (no-invasively). I was amazed at the things he told me about how human perception is easily fooled.

He had this funny experiment where he played a recording of sounds made at a public area. He would play back the exact same recording a second time and ask if the subject could hear something different. They always assumed that it was a different recording and would always hear something additional, even though it was trhe same recording. He had all sorts of interesting ABX tests as well. We are suckers for suggestion and mob hysteria, something that the marketing pukes just love to exploit.

post #986 of 989
Quote:
Originally Posted by TwoEars View Post
 

 

I think what he means is that without proper amplificaiton the HD800 will turn out bright and anoying.

 

300mW or 1000mW are just numbers and doesn't tell the whole story. The thing is however that if you find the right amp for the HD800 it can give you bass so deep and hard it makes your head shake! Not many know this... but a HD800 with the right amp and maybe a bit of EQ is really a bass lovers dream, and it won't be bright at all.

 

 

Quote:
Originally Posted by James-uk View Post


Well they are not just numbers they are power ratings. If an amp can output 20,000mW the hd800 won't use them. It will still only use it's required amount because otherwise it will burst your eardrums. I'm sure the hd800 needs about 250mW to reach 120 db. No need for anymore than that. Am I missing something?

 

Headroom is good alongside proper implementation and a clean circuit. The less an amp has to try, the less noise you get as a result of such. It's why using a Mjolnir with an 800 sounds good regardless of it having a near retarded amount of juice, because it's not only a very good amp for big power loads, but it's barely even doing anything to get you from A to B for lower work, so it makes my CIEM's with an impedance adapter sound super chill!

post #987 of 989
Quote:
Originally Posted by Chris_Himself View Post
 

 

 

 

Headroom is good alongside proper implementation and a clean circuit. The less an amp has to try, the less noise you get as a result of such. It's why using a Mjolnir with an 800 sounds good regardless of it having a near retarded amount of juice, because it's not only a very good amp for big power loads, but it's barely even doing anything to get you from A to B for lower work, so it makes my CIEM's with an impedance adapter sound super chill!

Noise? That's an entirely different topic and is not in context. Your statement "The less an amp has to try, the less noise you get as a result of such," does not make sense to me. An amp's noise (SNR) has nothing to do with it's power specs.

If one's amp as more power than is needed to deliver clean sound at the peaks according to the max volume one is listening at, the power is never used and has no value whatsoever. Too much power can damage one's ears and headphones. The HD800's product sheet lists the maximum long-term input power at 1/2 Watt which delievers just under 124 dB SPL according to their sensitivity specs.  Of course peaks can go higher. Nobody is going to listen at those levels. If you turn the volume down to 95 dB, which is still probably more than most people will listen at, the power requirement will be 0.67 mW or 0.00067 Watts. How much headroom does one require that would exceed 1/2 Watt? Probably none, maybe not even 1/2 W at the peaks. Most recorded music is compressed. We certainly don't need peak power levels that exceed the dynamic range limitations of source material or the audio chain.

By the way at 300 Ohms the Mjolnir only delievers 3.5 dB more power than the Asgard 2. I've listened to the HD800's on an Asgard 2 at ear splitting levels (briefly for the sake of my hearing) and heard no distortion on peaks,


Edited by StanD - 3/21/14 at 5:46am
post #988 of 989

^ what he said.  Welcome back StanD. :L3000:

post #989 of 989
Quote:
Originally Posted by koiloco View Post
 

^ what he said.  Welcome back StanD. :L3000:

Thanks, March was a rough month and April is bounce back.

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