[BassicScience]

Right, so an amplifier that can put out 0.5W at reasonable levels of distortion and an acceptable damping ratio will get the job done. More power than that will never be utilized by the headphone, unless you listen continuously at ear damaging volumes.

It really depends on how you define "will get the job done". Just about any amp will allow you to identify the song. After that, it's about degrees of refinement. No one, to my knowledge, is arguing that more power unconditionally equals better sound, but in my experience having an excess of power on tap often enhances the perception of sonic precision, especially at the frequency extremes. That isn't necessarily a positive thing to all listeners.

 

[simorag]

Being an automotive engineer I like to think it like this (amp designers / experts, sorry for over-simplification ).

Even a very low-powered engine will allow any car to reach and maintain, say, 150km/h on a flat road, allowing sufficient time to get to that speed.
That's the analogy to having 0.5W into a Susvara and playing it 110dB on a stationary 1kHz signal.

But, if you want to drive your car through a curvy uphill road with a lot of accelerations, overtaking other cars etc. with ease, then you need not only power but an engine with a lot of torque.

Musical signals are abruptly variable ones, much more difficulto to cope with than a stationary sinewave, and in order to keep up with them we don't only need power, but also the closest analogy to torque that comes to my mind, i.e. current delivery, which is in turn related to amplifier topology (e.g. class A is usually good at that), power supply design, damping factor etc..

Of course, if we get a speaker amp with 100W/8ohm or a class A 25W like the XA25 we can safely assume that the dimensioning of the amp itself is plenty sufficient by default to provide more than enough current to satisfy the Susvara hungerness.

On the flipside, I believe it is not true that you strictly NEED 5W or more on the Susvara load if the amplifier is designed to deliver even a much modest power (say 1-1.5W minimum) with a beefy peak current output reserve.

In actuality, I have listened to the Susvara through the Formula S / Powerman, an Air Tight ATM 300B (8W/8ohm), my Riviera AIC-10 and very strong speaker amplifiers (Pass XA25, Viva Solista, Krell KSA100) and I have been always satisfied with 'quantity' (grunt, dynamics, slam, ...).

Rather, the quality of the amp - and its synergy with Susvara signature - is what stands out the most, though, in terms of tonal accuracy, nuanced presentation, transparency, refinement, soundstage layering etc., which was not - in my experience - correlated to raw power (would rather say the opposite).

 

[Bonesy Jonesy]

A 83dB/mW 60ohm headphone will hit 110dB peaks with 0.5W, no headphone needs 7W, let alone 15W.

Well try a pair of Susvara's with an amp giving a measly 0.5 Watts output and tell all us Susvara owners what you hear ? And while you are at it, measure and tell us the voltage swing and current the amp is sending to the Susvara's !

 

[Bonesy Jonesy]

Well try a pair of Susvara's with an amp giving a measly 0.5 Watts output and tell all us Susvara owners what you hear ? And while you are at it, measure and tell us the voltage swing and current the amp is sending to the Susvara's !

And why not ask Hifiman direct why they uprated their EF-1000 from 8 Watts (which was for the HE-6) to 20 Watts at 35 Ohms (pure Class A output) for the headphone output specifically for the Susvara (with the current EF-1000 being the official amp pairing for the Susvara).

 

[L0rdGwyn]

Assuming an amplifier has a low output impedance across the audio band, the performance at the frequency extremes is independent of power output. That is, if the output impedance is low, the amplifier will supply any current demanded of the headphone when asked at any frequency. The amplifier circuit itself and the components in the signal path are going to have a greater impact on the sound quality than having "more watts".

I think the perception that "more power is better" is fueled by commercial headphone amplifier manufacturer marketing. Often more power IS better because higher quality amplifiers are being sold with higher power output specs. They don't want customers thinking "surely this amplifier is garbage, how could it possibly power my $3,000 headphones with a wimpy 0.5W output?".

I am particularly interested in tube amplifiers because that is what I design. One can build a 0.5W amplifier that uses high-quality parts and minimizes the number of reactive components in the signal path that sounds much, much better than a poorly designed 300B or other over-spec'd amp where the headphone will, in reality, use less than 1% of the available power.

 

[Bonesy Jonesy]

It really depends on how you define "will get the job done". Just about any amp will allow you to identify the song. After that, it's about degrees of refinement. No one, to my knowledge, is arguing that more power unconditionally equals better sound, but in my experience having an excess of power on tap often enhances the perception of sonic precision, especially at the frequency extremes. That isn't necessarily a positive thing to all listeners.

100% agree with you BassicScience. If people took the time to really understand how headphones work in particular Planar Magnetics then people wouldn't keep on about power requirements to such headphones as the Susvara. The official specification for the Susvara's to operate at is at least 8 Watts with a maximum tolerance of up to 25 Watts.

 

[Bonesy Jonesy]

Assuming an amplifier has a low output impedance across the audio band, the performance at the frequency extremes is independent of power output. That is, if the output impedance is low, the amplifier will supply any current demanded of the headphone when asked at any frequency. The amplifier circuit itself and the components in the signal path are going to have a greater impact on the sound quality than having "more watts".

I think the perception that "more power is better" is fueled by commercial headphone amplifier manufacturer marketing. Often more power IS better because higher quality amplifiers are being sold with higher power output specs. They don't want customers thinking "surely this amplifier is garbage, how could it possibly power my $3,000 headphones with a wimpy 0.5W output?".

I am particularly interested in tube amplifiers because that is what I design. One can build a 0.5W amplifier that uses high-quality parts and minimizes the number of reactive components in the signal path that sounds much, much better than a poorly designed 300B or other over-spec'd amp where the headphone will, in reality, use less than 1% of the available power.

Why don't you go and build a 0.5 Watts and let us know your findings or if you have already (to back up your information and claims) send us some nice photos of it and test measurements.

In the meantime, I am very much enjoying listening beautiful music with my wonderful Susvara's connected direct to my Chord Mezzo 140 Speaker Amp and giving them circa 15 Watts, and looking forward to demoing a Hifiman E-1000 with my Susvara's (and giving them circa 11 Watts) hopefully in February (UK COVID lockdown restrictions allowed).

 

[L0rdGwyn]

Well try a pair of Susvara's with an amp giving a measly 0.5 Watts output and tell all us Susvara owners what you hear ? And while you are at it, measure and tell us the voltage swing and current the amp is sending to the Susvara's !

Send me your Susvara and would be more than happy to, I'll take those measurements too. Better yet, you can do it! Open whatever amplifier you are using, get yourself a pair of alligator clips and a 60ohm resistor. Place the clips and resistor as a dummy load across the headphone output. Get a digital multimeter, set it to AC voltage, play a 1kHz test tone and increase the volume on your amplifier until it reads 5.4Vrms, that's 0.5W into a 60ohm load. Now remove the alligator clips and resistor, start playing some music, then plug in your Susvara, and see how long you can stand listening at 110dB.

And why not ask Hifiman direct why they uprated their EF-1000 from 8 Watts (which was for the HE-6) to 20 Watts at 35 Ohms (pure Class A output) for the headphone output specifically for the Susvara (with the current EF-1000 being the official amp pairing for the Susvara).

The answer to that question is so that you will want to buy them more.

Why don't you go and build a 0.5 Watts and let us know your findings or if you have already (to back up your information and claims) send us some nice photos of it and test measurements.

In the meantime, I am very much enjoying listening beautiful music with my wonderful Susvara's connected direct to my Chord Mezzo 140 Speaker Amp and giving them circa 15 Watts, and looking forward to demoing a Hifiman E-1000 with my Susvara's (and giving them circa 11 Watts) hopefully in February (UK COVID lockdown restrictions allowed).

You are not giving them 15W, even if the amplifier is capable of it. Do you own a digital multimeter or an oscilloscope? It is a simple measurement to make. Also, I am building a 0.5W amplifier, it will be done within a week. I will make it a point to track down a Susvara owner at a future Head-Fi meet to demonstrate.

 

[m17xr2b]

Assuming an amplifier has a low output impedance across the audio band, the performance at the frequency extremes is independent of power output. That is, if the output impedance is low, the amplifier will supply any current demanded of the headphone when asked at any frequency. The amplifier circuit itself and the components in the signal path are going to have a greater impact on the sound quality than having "more watts".

I think the perception that "more power is better" is fueled by commercial headphone amplifier manufacturer marketing. Often more power IS better because higher quality amplifiers are being sold with higher power output specs. They don't want customers thinking "surely this amplifier is garbage, how could it possibly power my $3,000 headphones with a wimpy 0.5W output?".

I am particularly interested in tube amplifiers because that is what I design. One can build a 0.5W amplifier that uses high-quality parts and minimizes the number of reactive components in the signal path that sounds much, much better than a poorly designed 300B or other over-spec'd amp where the headphone will, in reality, use less than 1% of the available power.

I tried, some don't understand the technical side of it, hearing 0.5W they think underpowered yet fail to realise the impedance this is into, 60 Ω, and without the experience of the innards of tube amps it's hard to grasp why this will work. Wishing 10 + 10 needs to be 100 isn't how this goes.

Why don't you go and build a 0.5 Watts and let us know your findings or if you have already (to back up your information and claims) send us some nice photos of it and test measurements.

I have, 0.3W and 2W, told about it a few posts back, it works because of maths.

 

[Bonesy Jonesy]

Send me your Susvara and would be more than happy to, I'll take those measurements too. Better yet, you can do it! Open whatever amplifier you are using, get yourself a pair of alligator clips and a 60ohm resistor. Place the clips and resistor as a dummy load across the headphone output. Get a digital multimeter, set it to AC voltage, play a 1kHz test tone and increase the volume on your amplifier until it reads 5.4Vrms, that's 0.5W into a 60ohm load. Now remove the alligator clips and resistor, start playing some music, then plug in your Susvara, and see how long you can stand listening at 110dB.



The answer to that question is so that you will want to buy them more.



You are not giving them 15W, even if the amplifier is capable of it. Do you own a digital multimeter or an oscilloscope? It is a simple measurement to make. Also, I am building a 0.5W amplifier, it will be done within a week. I will make it a point to track down a Susvara owner at a future Head-Fi meet to demonstrate.

Yes I do and I have tested my Susvara's both with my Mezzo 140 Speaker Amp and directly connected to my Chord DAVE thank you very much.

 

[Bonesy Jonesy]

Yes I do and I have tested my Susvara's both with my Mezzo 140 Speaker Amp and directly connected to my Chord DAVE thank you very much.

I have done my research homework and testing. I am happy with what I found and now know !

 

[Fegefeuer]

If you can afford a Susvara and all that Chord stuff you surely can afford "a pair of alligator clips and a 60ohm resistor" and do the testing instead of being so dismissive?

 

[L0rdGwyn]

@Bonesy Jonesy if you wanted to measure how much power is being used by the Susvara at your listening volume, I would be more than happy to tell you how to do it. I'm not trying to be rude, but there is a misconception on Head-Fi about how much power a headphone needs, fueled I think by what is being marketed to Head-Fiers. In reality, even the most demanding headphones don't need anywhere near the amount of power some of these amps are capable of providing. Quality is much more important than quantity! It just so happens the two go hand-in-hand because that is what is being sold - quality amplifiers with high power output, but it doesn't necessarily need to be that way.

 

[ThanatosVI]

Basically everyone of us knows that headphones won't use the full 8W, 10W or whatever an amp is capable of.

However for Sound it often is the best if the amp is bored and doesn't use more than ~10-20% of it's Max power because it's most linear in that range depending on design

 

[BassicScience]

@Bonesy Jonesy if you wanted to measure how much power is being used by the Susvara at your listening volume, I would be more than happy to tell you how to do it. I'm not trying to be rude, but there is a misconception on Head-Fi about how much power a headphone needs, fueled I think by what is being marketed to Head-Fiers. In reality, even the most demanding headphones don't need anywhere near the amount of power some of these amps are capable of providing. Quality is much more important than quantity! It just so happens the two go hand-in-hand because that is what is being sold - quality amplifiers with high power output, but it doesn't necessarily need to be that way.

You're not really wrong. When I first bought my Susvara, I was driving it with a Rogue Audio RH-5 integrated headphone amp (3.5W into 32 ohm) and the sound was entirely satisfactory, even excellent. Did I "need" more power? Not really, any more than a commuter "needs" a 600 horsepower Ferrari. But if you want the Ferrari experience (or the Hypex Class D sound, in my case), and 600 horses (300 watts) is the minimum they offer, then that's what you buy. You don't really need that much power, but it's not a detriment either.