Headphone Amp: Harsh vs Smooth

[Blur]

I've been listening and comparing headphone gear for over 20 years now and want to see if any of you have the same experience as I.

The Gear:
Schiit Magni 3
SMSL SP200 THX ( Using the single ended inputs and output )
Headphone: Aeon Flow Open ( 2 notch filters )

With the Magni 3 I notice immediate relief from harshness that I find in the SP200. This includes all of my standard hi-fi test tracks that I have spent months making into a playlist for review. If I swap back to the SP200 ( low gain ) I immediately feel the sensation of harshness and my ears start to need a break. It's a subtle pain in my ear and most indicative of ear fatigue when the bones in your ear have had enough and there is muscle strain. I swap immediately back to the Magni 3 and it's like my ears just took a Tylenol. The harshness is gone.

Things to note:
I still need to dig out my SPL meter so I can match the listening levels as it may be simply a loudness issue. I did try to match the loudness by ear, but due to the massive gain ( even in low gain on the SP200 ) it is easy to get very loud quickly.

Have any of you had a similar experience? Any ideas as to what is causing it? Usually it is caused by treble peaks and I eliminate it by changing the angle of the headphone driver. With amps I'm really not sure what the cause is, but it can be painful so I'm trying to understand the source.

 

[Blur]

Can different amps create different pressure levels on the same headphone, but still have the same output voltage to the headphone?

 

[Soniclife]

You want to use a multimeter, not a mic to match levels.

 

[Blur]

Yeah good idea. Also, one other piece of the puzzle is I listen at low levels on the volume pot. For the SP200 I’m talking less than 15% of the range. I wonder what the measurements look like in the 50mV range.

 

[majingotan]

It's sighted listening BTW which can easily influence what we perceive. You might wanna do a quick DBT volume matched test just to ensure you're not hearing "harsh" from one of them.

 

[solderdude]

Can different amps create different pressure levels on the same headphone, but still have the same output voltage to the headphone?

yes, but not with the AEON flow. SPL meter is not suited for level matching. Making a proper level matched comparison between headphone amps really is not that easy.

What you could try is the following:
A: Use a music source with volume control
B: connect the output to both HA's
C: Level match as closely as possible (by ear) between the 2 headphone amps using the volume control of the amps.
D: Have someone else swap the headphone plug from 1 amp to the other or they pull the plug and put it back. The essence here is that YOU must not know which amp it is plugged into and you do not see the second person.

Listen to music of your choice. When it is time to swap you dial down the volume of the music. Tell the helper to swap.
The key here is that he pulls out the plug and either switches it to the other amp or sticks it back in.
He makes notes what he/she did and you evaluate.
You can have full control over the music source and volume (but not on the amps).
Make sure you have enough attempts.
It could be ABBBAABAAABAAAAAAAABBA for instance (you not knowing the sequence)
If you can reliably pick out the 'harsh' one there is something wrong with that amp or it is overdriven or not really compatible with the very low impedance of the AEON.

 

[Blur]

I think I found the issue. Definitely loudness related and after swapping gear around headphone placement also played a roll. The primary cause was the loudness and NOT the amp. Now the SP200 sounds smooth. A few dB sure makes a difference.

 

[Blur]

Thank goodness. I was starting to second guess my common sense.

 

[majingotan]

I think I found the issue. Definitely loudness related and after swapping gear around headphone placement also played a roll. The primary cause was the loudness and NOT the amp. Now the SP200 sounds smooth. A few dB sure makes a difference.

That's the thing with headphones for me. They quickly sound fatiguing at loud volumes unlike near field speakers where I can blast it at club party loudness levels (90+ dB SPL) 45cm from my ears and never feel strained whatsoever. Don't know why but maybe headphones bypass the pinna structure of my ear leading to elevated peaks in the treble part. If I EQ it to minimize the peaks, it does not sound correct to my subjective preference

 

[Blur]

Driver angle plays a huge roll for me. If the pads are already angled I usually play around a bit with the angle if I’m fighting treble fatigue. At least it wasn’t the amp!

The HE-400i is a perfect example. The standard angle of the pads provides too much treble energy for my ears. If I reverse the angle, problem solved.

 

[Wombat]

That's the thing with headphones for me. They quickly sound fatiguing at loud volumes unlike near field speakers where I can blast it at club party loudness levels (90+ dB SPL) 45cm from my ears and never feel strained whatsoever. Don't know why but maybe headphones bypass the pinna structure of my ear leading to elevated peaks in the treble part. If I EQ it to minimize the peaks, it does not sound correct to my subjective preference

Maybe you just don't realise the SPL the 'phones are delivering without the cues and effects/affects one gets in-room.

 

[majingotan]

Maybe you just don't realise the SPL the 'phones are delivering without the cues and effects/affects one gets in-room.

Maybe I'm seeking the same "music energy/sensation level" on the headphones that I get on my speakers and actually turning it up much louder than what I play with my speakers which probably is why I get tired of listening to headphones far quicker compared to listening near field at OSHA max 8 hour exposure level (aka 90 dBa SPL)

 

[Soniclife]

Maybe I'm seeking the same "music energy/sensation level" on the headphones that I get on my speakers and actually turning it up much louder than what I play with my speakers which probably is why I get tired of listening to headphones far quicker compared to listening near field at OSHA max 8 hour exposure level (aka 90 dBa SPL)

Sounds likely, the physical impact of bass is missing with headphones, messes up our brains processing of volume.

 

[Blur]

Hard to achieve much bone conduction with a headphone.

 

[Veri]

I think I found the issue. Definitely loudness related and after swapping gear around headphone placement also played a roll. The primary cause was the loudness and NOT the amp. Now the SP200 sounds smooth. A few dB sure makes a difference.

Good testing and good call

 

[LTig]

Hard to achieve much bone conduction with a headphone.

It is possible though to create something similar. 25 years ago a colleague visted me and brought his brand new Sennheiser HD580 for listening. We connected it to the CD player (the only way I had to connect a headphone) and when I listened to organ music I felt the bass vibrating in my breast. I told my colleague to switch off the speakers but they were already switched off. Next day I bought a HD580.

Same happens when I listen to my HD800. Sometimes I have to take it off to make sure the speakers are not playing.

But there is another quieter possibility to get bone conduction.