[kennyb123]

I've heard in various places that the Aeons 2 have more dynamics and bass response with really high wattage amps, way more than Dan Clark recommends. Did you try the Aeons with a beefier amp? It's not just about volume, it's about punch and dynamics.

In the automotive world, we are fortunate to have two meaningful stats about an engine’s performance: horsepower and torque. Horsepower gives us insight into a car’s top speed while torque gives us insight into how quickly the car accelerates.

The power rating of an amplifier is akin to horsepower. It tells us if the amp will drive the headphones to a sufficient volume without running out of steam. Since music is dynamic, what we really need though is a metric that’s akin to torque. That would give us insight into how well the amp can deliver current dynamically to meet the demands of the music. This is the quality that the Aeons seem to need to come alive.

 

[KaiSc]

I normally set the listening level to 120dB for a bit of headroom which ends up at a little over 600mW required power.
Strangely enough that's about what Dan Clark recommends...

I'm not convinced that more power makes any difference, once the headphones are sufficiently powered.

The iFi device you posted would have plenty of power while balanced but falls short single ended.

The calculator: https://www.headphonesty.com/headphone-power-calculator/ is a useful tool.
But only if you put in realistic values for listening level.
E.g. 10 dB too high estimated level means 10 times more requested power, a big difference!

This unnecessarily limits the choices of amps and portables devices, leads to missing an occasion.


120 dB SPL is like shooting a small bore rifle without earprotection, not advisable even for the very short event of a shot, if one wants to preserve ones hearing.


The calculator defaults to 110 dB SPL, a level that you may expose yourself for less than 2 min a day (!) to prevent hearing damage, according to NIOSH standards:
https://blogs.cdc.gov/niosh-science-blog/2016/02/08/noise/

If you don‘t ask for more, DCA Aeon 2 Noire is sufficiently driven by a lot of amps.
This correlates with my own experience, that even says, having an amp with 10 or 100 times the power capability doesn’t change the sound the slightest.


BTW: The car’s horsepower analogy doesn’t fit.
Audio signals are alternating (AC-voltage) between plus and minus, permanently accelerating back and forth, up to 20,000 times a second.
A car is going one direction only, äquivalent to DC.


For the 13 Ohm low impedance DCA Aeon 2 Noire it’s an amps current capability that mainly counts.

 

[kennyb123]

BTW: The car’s horsepower analogy doesn’t fit.
Audio signals are alternating (AC-voltage) between plus and minus, permanently accelerating back and forth, up to 20,000 times a second.
A car is going one direction only, äquivalent to DC.

You totally missed the point.

How electrons actually flow is not the point. I'm talking about the flow of energy. Energy propagates in a single direction - from our amps to our headphones. This should be common sense.

My point was that amps have varying degrees of being able to meet instantaneous demands. This is a fact.

You should probably read up on internal combustion engines. Pistons alternate back and forth.

 

[KaiSc]

You totally missed the point.

How electrons actually flow is not the point. I'm talking about the flow of energy. Energy propagates in a single direction - from our amps to our headphones. This should be common sense.

My point was that amps have varying degrees of being able to meet instantaneous demands. This is a fact.

You should probably read up on internal combustion engines. Pistons alternate back and forth.

A funny concept:

An amp should need a run-up to deliver energy - while in fact it accelerates, stops and then reverse accelerates the drivers diaphragm at least 20,000 times a second.

An amp not capable to instantaneously react would not deliver any high frequencies at all.
In fact amps can do this back and forth at much higher frequencies, 768,000 Hz in case of a DSD-compatible one.

To stay with the car analogy:
Like going from 0 to 100 km/h in 1/40,000 of a second, then stop and going back the same speed is an amp’s normal job.


The Aeon 2 Noire isn’t even a reactive load, the amp doesn’t see a back-EMF (a current that feeds back, generated from the driver‘s motion), like it does with a dynamic driver.
Aeon 2 Noire, like all planars, presents a almost purely resistive load, the least challenge for an amp.

 

[purplehazed]

The calculator: https://www.headphonesty.com/headphone-power-calculator/ is a useful tool.
But only if you put in realistic values for listening level.
E.g. 10 dB too high estimated level means 10 times more requested power, a big difference!

This unnecessarily limits the choices of amps and portables devices, leads to missing an occasion.


The tool defaults to 110 dB SPL, a level that you may expose yourself for less than 2 min a day (!) to prevent hearing damage, according to NIOSH standards:
https://blogs.cdc.gov/niosh-science-blog/2016/02/08/noise/


If you don‘t ask for more, DCA Aeon 2 Noire is sufficiently driven by a lot of amps.
This correlates with my own experience, that even says, having an amp with 10 or 100 times the power capability doesn’t change the sound the slightest.

I'm reading everywhere that the Aeon 2s bring the bass and dynamics with high wattage amps. I'm not sure if it is maintaining

A funny concept:

An amp should need a run-up to deliver energy - while in fact it accelerates, stops and then reverse accelerates the drivers diaphragm at least 20,000 times a second.

An amp not capable to instantaneously react would not deliver any high frequencies at all.
In fact amps can do this back and forth at much higher frequencies, 768,000 Hz in case of a DSD-compatible one.

To stay with the car analogy:
Like going from 0 to 100 km/h in 1/40,000 of a second, then stop and going back the same speed is an amp’s normal job.


The Aeon 2 Noire isn’t even a reactive load, the amp doesn’t see a back-EMF (a current that feeds back, generated from the driver‘s motion), like it does with a dynamic driver.
Aeon 2 Noire, like all planars, presents a almost purely resistive load, the least challenge for an amp.

I think that there's a distinction to be made, and that is that the bass could make the driver move a bigger distance and suck more watts than your typical treble or mids. That could be the cause for all of this.
Too many people, including reviewers with a lot of experience are mentioning this behavior with low efficiency planars.

 

[KaiSc]

I'm reading everywhere that the Aeon 2s bring the bass and dynamics with high wattage amps.

I think that there's a distinction to be made, and that is that the bass could make the driver move a bigger distance and suck more watts than your typical treble or mids. That could be the cause for all of this.

Exactly!

A look on a Real Time Analyzer (like the one in RME ADI-2, or any other) clearly shows that bass level peaks above midrange and treble with most music.
So if an amp overdrives, “runs out of steam”, the bass is affected first.

Usually this is clearly audible as scratchy distortions, but todays pop music masters are pushed over the top so far that this scratchy sound is the new “normal”.


Finally it boils down to how loud one likes to listen.

For me, with the DCA Aeon 2 Noire, 20 mW is already beyond of what I need - for dynamic recordings like Jazz, Classic or such!
E.g. this very dynamic 4th part of TELARC‘s 1978 Stravinsky - Firebird:
https://tidal.com/track/166905481

With current Pop I do use up to 2 mW only!
My ADI-2 Pro gives me visual control for this - it’s meters show the dBu value of it’s headphones output.

I don’t listen very quiet - vocals in the music come out some above the level of a normal conversation.

 

[kennyb123]

An amp should need a run-up to deliver energy - while in fact it accelerates, stops and then reverse accelerates the drivers diaphragm at least 20,000 times a second.

In the real world there can be a lag. It’s why the slew rate is an important consideration for the designer. The slew rate is a measurement of how quickly an amplifier is able to respond to a change in input level. If the amplifier can’t react quickly enough we are left with what’s pictured.

 

[KaiSc]

Regarding amplifier slew rate:

Instead of looking on some hand drawn phantasy zig-zag, why not look at real data from a real amplifier?

This is from the data sheets of the TI OPA1622, the chip that is used in RME ADI-2’s headphones amp:
Look at figure 26.

You can see that for a large scale signal the amp takes about 1/2 millionth of a second (0.5 µs) to go 0 – 5 V.
This has no influence on audio signals, where the fastest signal, 1/4 of a 20 kHz wave, is 25 times slower.

Not to mention the very much slower signals in mid range and bass.

The run up or time lag in the way you imagine does not exist.

 

[kennyb123]

Not to mention the very much slower signals in mid range and bass.

The run up or time lag in the way you imagine does not exist.

I'm not going to engage with you further as it doesn't appear you can even grasp what I've been arguing. You can't allow for differences in amplifiers so you can continue to proclaim that all amps sound the same.

The op amp that you selected to show stats on has a slew rate of 10 v/us. Yes, that means that it can output 10 volts in a microsecond. But there is more to a headphone amplifier than an op amp and some avoid op amps altogether. But as I said, slew rate doesn't tell us about an amp's dynamic capabilities. It's only one aspect of an amplifier's performance.

The reason I brought up slew rate was to refute your argument that there can be no lag since we are dealing with AC. If that were true, we wouldn't have varying slew rate measurements because every amp would do this perfectly.

I grabbed that illustration from this article. It's a really good article on what slew rate actually tells us.

I’ve been speaking in terms of the time domain. Good frequency domain performance doesn’t necessarily mean good time domain performance. This is why listeners observe that some amps are better than others at delivering punch. Noise has a lot to with this as it effects our perception of the starting and stopping of notes.

 

[KaiSc]

You’re right, now I don’t know what you’re heading for.
Probably I got lost in your car analogy.


Just to correct your assumption about my opinion:
I never say all amps are the same, and listening very carefully tiny differences are audible.

Even more so on speaker amps driving heavy loads, specially some older PA-amps suffer from audible treble problems due to slew rate limiting.

With a great variety of headphone amps I tested I never found such obvious differences.
Small power amps in general are much faster, as transistors speed largely depends on chip size and therefore power capability.

 

[purplehazed]

Could someone measure the leather headband strap width (the short distance) ? I would really appreciate it, I'm trying to find a compatible headphone stand. Thank you.

 

[Patu]

Tried the Noire briefly and here are some impressions. The pads on the Noire felt disfigured. They didn't even match perfectly between the right and left side. Sound notes: I found them underwhelming to be honest. These are what I could call 'flat' in my head. Flat not as in matching a specific Harmann target, but flat as in, everything sounded like someone machined off all the enjoyable parts of the song. It's perfectly smoothened out. I didn't get the kick of the drum, neither I got the excitement of a bass guitar or the emotions of the singer. They were flat as in dead. I had a particularly strong impression about these because these are not my thing at all.

It sounds like your headphone amp wasn’t up to the task with Noire’s. Your description is so far from what I hear with them paired with RME ADI-2 FS.

 

[KaiSc]

Could someone measure the leather headband strap width (the short distance) ? I would really appreciate it, I'm trying to find a compatible headphone stand. Thank you.

The width is 48 mm.
But I suggest to hang it on the headarc’s metal wires, they are 18 mm apart

Real leather headbands tend to stretch and defom when used for hanging.

Important:
Have it hanging free on the earcups.
Nothing should squish the earpads, even better put the supplied hardfoam piece inside the cups to keep them little apart.

 

[ubs28]

I use this headphone with a nuclear fusion reactor and the slam is amazing.

 

[kennyb123]

But I suggest to hang it on the headarc’s metal wires, they are 18 mm apart

+1 That’s how I do it.