Dan Clark Audio AEON RT Review (closed headphone)

[Bernd]

Hello , just for your info. I just bought a secondhand Little Dot MKII for fun to see how that compares to the headphone output stage of the RMI ADI DAC FS 2 and ..... well..... they do not like each other at all : at the loudness level I like, the MK II sounds awfull and distorted: However , with my Focal Clear there is absolutley no issue. So the AEON RT is really not very efficient.

 

[RHO]

Hello , just for your info. I just bought a secondhand Little Dot MKII for fun to see how that compares to the headphone output stage of the RMI ADI DAC FS 2 and ..... well..... they do not like each other at all : at the loudness level I like, the MK II sounds awfull and distorted: However , with my Focal Clear there is absolutley no issue. So the AEON RT is really not very efficient.

Could it be an impedance issue? The Aeon RT is very low-ohmic.

 

[solderdude]

Could it be an impedance issue? The Aeon RT is very low-ohmic.

it is a load impedance issue.
The LD cannot possibly deliver the needed current for it to reach even normal listening levels and thus the LD is (current limited) clipping the output signal.
It can only supply 50mA = 40mW (distorted) in 13 ohm = 0.7V (95dB SPL peak) ... which is even less than your typical phone.

 

[3kweave]

The Aeon RT is a very thirsty headphone! Its right there in Amir's graphs. Assuming no EQ, the RME could push it to about 108db at 97DB/V 78mw/dB. Since I already had the RME I figured I would go with the A2CN which has a slightly better sensitivity of 86.5 db/mw or 104.9db/v so the RME should be able to push it to 114db. Although I am quite the bass head so I add in a 5db low shelf from 105hz and for non-bass heavy music the RME gets louder than I can handle. Tracks with a HEAVY bass, I feel like I might benefit from a little more power. I am not quite sure how to do the math on calculating power demands when a 5db low shelf is used.

 

[dpippel]

@amirm - Any plans to review the AEON 2 Noire?

 

[Lttlwing16]

Hey quick question, loving the Aeon RT so far, but had a quick question. I didn't really pay close attention and plugged in the supplied dummer balanced headphone cable with the red band on the left headphone and didn't realize it until tonight when I was looking at some reviews and the red band was on the right. Everything seems fine, just didn't know what impact (apart from mixing L/R channels) would be.

 

[frogmeat69]

Hey quick question, loving the Aeon RT so far, but had a quick question. I didn't really pay close attention and plugged in the supplied dummer balanced headphone cable with the red band on the left headphone and didn't realize it until tonight when I was looking at some reviews and the red band was on the right. Everything seems fine, just didn't know what impact (apart from mixing L/R channels) would be.

None, except for the channels swapped.

 

[Wegi76]

Hi there,

can someone help me with the correct formula to calculate the SPL based on the specs of the headphone and the maximum power of my mobile DAC/Amp? I hope these parameters are sufficient to calculate it...

Headphone should be12,5 Ohms and 85,9db/mW. Amp should be able to generate roughly 180mW* on the balanced output.

Thank you!

*Im guessing here... It`s a Qudelix 5K...Amir measured it with 210mw @ 50 Ohms but the vendor states it runs into a power saturation limit on low impedance headphone. Here`s a an example for a 9Ohms headset...therefore my estimation.

 

[Robbo99999]

Hi there,

can someone help me with the correct formula to calculate the SPL based on the specs of the headphone and the maximum power of my mobile DAC/Amp? I hope these parameters are sufficient to calculate it...

Headphone should be12,5 Ohms and 85,9db/mW. Amp should be able to generate roughly 180mW* on the balanced output.

Thank you!

*Im guessing here... It`s a Qudelix 5K...Amir measured it with 210mw @ 50 Ohms but the vendor states it runs into a power saturation limit on low impedance headphone. Here`s a an example for a 9Ohms headset...therefore my estimation.

112dB is the answer based on the information you've given:
https://www.h-ear.audio/2019/06/01/headphone-power-calculator/

 

[Wegi76]

Thank you! That should be loud enough then.

 

[Robbo99999]

Thank you! That should be loud enough then.

I think it will be loud enough, as long as you're not tipping your DAC/amp into distortion territory:

With a 33ohm load that's already happening above 85mW, so as long as you've done your calculations properly based on 12.5ohms in terms of your DAC/amp being able to deliver 180mW without distortion then you're fine.

EDIT: ah, found this other graph, so with the balanced connection your mentioned you should be fine as here's 50ohm balanced at 210mW max:

 

[Wegi76]

Yep that`s the chart I ment. I found out that the Qudelix Power Budget Tables can be modified (they include the formulas) Here`s what the "hacked" Qudelix tables spits out for the 12.5 ohms / 85.9dB/mW values of the Aeon RT... See here... For 180mW this results in just 108.5dB and not 112dB @Robbo99999 The numbers align to the calculator you linked. above. For 112dB you`d need >400mW as it seems.

 

[Jimbob54]

Hi there,

can someone help me with the correct formula to calculate the SPL based on the specs of the headphone and the maximum power of my mobile DAC/Amp? I hope these parameters are sufficient to calculate it...

Headphone should be12,5 Ohms and 85,9db/mW. Amp should be able to generate roughly 180mW* on the balanced output.

Thank you!

*Im guessing here... It`s a Qudelix 5K...Amir measured it with 210mw @ 50 Ohms but the vendor states it runs into a power saturation limit on low impedance headphone. Here`s a an example for a 9Ohms headset...therefore my estimation.

Things get complicated because the DCA is both low impedance and (perhaps more important) low sensitivity. Im not sure the hacked power tables factor in the amp running out of juice like the official qudelix tables do. I'd also look at the Hifiman 5XX as an example- planar , low impedance and low(er) sensitivity- high sensitivity IEMs arent a good comparator.

Will you be planning to use EQ either in the 5k or before ? If so, this will compound the problem.

I have the Aeon RT open and the Qudelix and I EQ roughly to Oratory 1990 harman EQ so I will run them together tomorrow and see what happens! I'm not a massively loud listener so if it tops out, really wont do for higher volumes.

 

[Wegi76]

That`s very kind of you, Jimbob54, thanks! And although I did not hear it yet, I`d probably EQ it,yes . Regarding the hacked table: No, I did not factor in the limit. I don`t know where it is exactly and simply pulled down the formulas.

BTW: I took the sensitivity information from this site. I hope this is correct data. User ririt on page 19 had the same idea but came to completely different results. He used 78dB/mV instead of "my" 85.9dB/mW. It`s really getting confusing.

 

[musicarcade]

I am hoping someone can answer question for me - I recently acquired A set of DCA VIVO cables with my aeon rt , Well I love the cables, but I think I really need a balanced instead of unbalanced cable . Do I really need to buy a whole different set of cables or is it possible to change the connector from unbalanced to balanced?

 

[Jimbob54]

That`s very kind of you, Jimbob54, thanks! And although I did not hear it yet, I`d probably EQ it,yes . Regarding the hacked table: No, I did not factor in the limit. I don`t know where it is exactly and simply pulled down the formulas.

BTW: I took the sensitivity information from this site. I hope this is correct data. User ririt on page 19 had the same idea but came to completely different results. He used 78dB/mV instead of "my" 85.9dB/mW. It`s really getting confusing.

Good news - my EQ runs about -2.5 to -4 dB preamp reduction. The 5k set at 0dB is plenty loud enough for me and thats with the phone output down a couple of dB too. Given the 5k can go up to +6dB oh high output setting I reckon you should be fine. This was the Aeon RT Open but suspect the closed isnt much different a load.

Thats not to say it wasnt increasing the THD- but it sounded good to me. This was connected by USB- I'm not as convinced by the Bluetooth if I am honest.

 

[Lttlwing16]

What filter pads are folks using? Is there a place where someone has measured the FR of each different set? I've tried none, single notch white, and double notch white, and prefer the double notch white so far.

 

[RHO]

What filter pads are folks using? Is there a place where someone has measured the FR of each different set? I've tried none, single notch white, and double notch white, and prefer the double notch white so far.

I'm using the thin black foam ones for now.
Yeah, I'm also interested in seeing what the effect is on the FR curve.

 

[Jumbotron]

What filter pads are folks using? Is there a place where someone has measured the FR of each different set? I've tried none, single notch white, and double notch white, and prefer the double notch white so far.

I removed the preinstalled one-notch white filter pads and have my Aeon RT (closed) equalized with Equalizer APO following Oratory1990's suggestions. Although I might tweak that EQ a little bit, they still sound a bit too sharp in the high frequencies to my taste.

 

[bboris77]

What filter pads are folks using? Is there a place where someone has measured the FR of each different set? I've tried none, single notch white, and double notch white, and prefer the double notch white so far.

I am using the preinstalled one-notch white filter pads. Have not even tried the other ones as I am very happy with the default set. I it ain't broke, don't fix it.