[jlbrach]

I also love my 846 with my AK 120 Titan using WAV files....simply wonderful

 

[Audiowood]

  Purely objectively the 3ohm output causes a 2.5dB variance in frequency response compared to 0ohm.  Essentially making the resulting curve sound like you were using the filter one below what you are.  White becomes blue, blue becomes black, black becomes mud
 
Which I actually find really useful since on the road the extra bottom end helps drown out low frequency background noise like road noise or engines while at home I don't need the boost.

 
Yeap, I have similar findings subjectively. 0 or 1 ohm sound great with SE 846, anything higher I always end up adding 1 or 2db up on the treble to compensate. So for example, in my ZX1, I need to add +2/3 on 16K and +1 on 6K on ZX1 in order to have the same treble energy on my M8 (1ohm) and Dacport 1(ohm) with no EQ at all. But then the plus point is the bass gets slightly heavier on zx1 (which sound good although not as tight). When I play with the imp switch on M8, the higher setting of 11 ohm sounded veil, bassy (muddy), slightly U shape vocal and dark than the 1 ohm level where the vocal is louder, cleaner and treble more airier and bass tighter Some people prefer 11ohm and some 1 ohm. so this is a very subjective experience but the point here is the impedance plays a very crucial role in the final SQ, so diff impedance for diff phones produce a totally diff sound quality. my 2 cents!

 

[vlach]

Yeap, I have similar findings subjectively. 0 or 1 ohm sound great with SE 846, anything higher I always end up adding 1 or 2db up on the treble to compensate. So for example, in my ZX1, I need to add +2/3 on 16K and +1 on 6K on ZX1 in order to have the same treble energy on my M8 (1ohm) and Dacport 1(ohm) with no EQ at all. But then the plus point is the bass gets slightly heavier on zx1 (which sound good although not as tight). When I play with the imp switch on M8, the higher setting of 11 ohm sounded veil, bassy (muddy), slightly U shape vocal and dark than the 1 ohm level where the vocal is louder, cleaner and treble more airier and bass tighter Some people prefer 11ohm and some 1 ohm. so this is a very subjective experience but the point here is the impedance plays a very crucial role in the final SQ, so diff impedance for diff phones produce a totally diff sound quality. my 2 cents!

If I'm not mistaken the rule of thumb is a ratio of 8/1, headphone/amp impedance, therefore I can see why the 1 ohm setting would work best with 8 ohm headphones.

 

[JAG87]

   
Yeap, I have similar findings subjectively. 0 or 1 ohm sound great with SE 846, anything higher I always end up adding 1 or 2db up on the treble to compensate. So for example, in my ZX1, I need to add +2/3 on 16K and +1 on 6K on ZX1 in order to have the same treble energy on my M8 (1ohm) and Dacport 1(ohm) with no EQ at all. But then the plus point is the bass gets slightly heavier on zx1 (which sound good although not as tight). When I play with the imp switch on M8, the higher setting of 11 ohm sounded veil, bassy (muddy), slightly U shape vocal and dark than the 1 ohm level where the vocal is louder, cleaner and treble more airier and bass tighter Some people prefer 11ohm and some 1 ohm. so this is a very subjective experience but the point here is the impedance plays a very crucial role in the final SQ, so diff impedance for diff phones produce a totally diff sound quality. my 2 cents!

 
Yes sir, output impedance is about the only thing that significantly affects sound quality besides source material and transducers.

 

[Solude]

If I'm not mistaken the rule of thumb is a ratio of 8/1, headphone/amp impedance

 
These are not dynamic drivers.  The rules of full sized speakers don't apply.  The 8:1 rule goes out the window when dealing with devices that get their response modified by using inline resistance.  Using Etymotic as an example, their 100ohm ER-4S is 9ohm earphone and 91ohm inline impedance, ie effectively as if the amp had a 91ohm output impedance given it a 1:10 ratio and yet no control loss.

 

[vwinter]

Yes sir, output impedance is about the only thing that significantly affects sound quality besides source material and transducers.

These are not dynamic drivers.  The rules of full sized speakers don't apply.  The 8:1 rule goes out the window when dealing with devices that get their response modified by using inline resistance.  Using Etymotic as an example, their 100ohm ER-4S is 9ohm earphone and 91ohm inline impedance, ie effectively as if the amp had a 91ohm output impedance given it a 1:10 ratio and yet no control loss.

Output impedance is just a number. It depends on the design of the "speaker."
Etymotic obviously designed the ER-4 with this in mind.

 

[Solude]

Etymotic was an example.  Balanced armatures as a technology are tuned with a combination of inline resistors and acoustic dampeners in the nozzle.  Output impedance is important in speakers due to their reactive load and mass.  That said, output impedance in the amplifier will shift the entire band where resistors dedicated to a single BA don't interfere with the others.
 
All that to say, with balanced armature in ears we aren't concerned with output impedance as it related to dampening but it's effect on frequency response or rather the change at certain ranges based on what the iems impedance curve looks like.  But it also swings both ways.  High impedance will change the curve but the change might actually result in better sound.  Easy example is high impedance corrects for the Westone mid bass bloat, win, but sucks the midrange out of some Shure models, fail.

 

[truckdriver]

I don't know about the impedance thing, but if I had to choose between the varying descriptions of its effects, I'd go with the "neutral" filter sounding like the white fliter. I'd disagree that the black will thus sound like "mud". The black should actually sound "neutral" (following the logic). In fact, it would be more neutral due to it not having the same bass enhancement as the other two filters.
 
I find myself turning up the mids (and not the highs) with the neutral (blue) filter on my (supposedly) high output impedance T'Mo Galaxy S2. I also turn up the bass but that's because I love bass. I especially enjoy the deep growling bass. I love the growl.

 

[Tobias89]

I love the combination of AK120 plus my SE846's

Its expensive though.for now.and hard to find where i am.

 

[Tobias89]

Yes sir.  Very nice combination.

Wow.how does it sound like? Might be tempted to give it a shot

 

[Solude]

   I'd disagree that the black will thus sound like "mud". The black should actually sound "neutral" (following the logic). In fact, it would be more neutral due to it not having the same bass enhancement as the other two filters.

 
HeadRoom reran the measurement on a more recent batch and the graphs now show the black filter as expected and not borked like the first one they measured.  Which is to say acoustic dampeners doing what they do.
 

 

[truckdriver]

   
HeadRoom reran the measurement on a more recent batch and the graphs now show the black filter as expected and not borked like the first one they measured.  Which is to say acoustic dampeners doing what they do.
 
 

 
Reran? Did the measuring equipment “fall asleep” on the black filter measurement on the “first run”? That black filter "tricked" Headroom and Inner-fidelity. I was going by Innerfidelity's measurements. The last time I used the black filter was with my first (batch) 846.

 

[Solude]

InnerFidelity, ie Tyll, is the one who provides HeadRoom their measurements.  The two have slightly different criteria but use the same equipment and tech.  The nice thing about IF is we also get to see measurements for cans that HeadRoom doesn't sell.  If I had to guess I would say the first graph for the black either wasn't seated properly or had a poor seal.

 

[ljhhh]

Demo-ed the Shure SE846 and my first impressions was pretty dissapointing. Perhaps my expectations are a little too high, but I find that it wasn't worth the upgrade from my SE535 instead at this price.

 

[Solude]

Perhaps my expectations are a little too high, but I find that it wasn't worth the upgrade from my SE535 instead at this price.

 
Highlighted the important part here.  And I agree.  The 846 is very good but like most things audio deep into diminishing returns.  But like most things deep in diminishing returns... no real alternative at a lower cost /shrug
 
A lot like the LCD-2 Rev2 and the LCD-3.  LCD-3 is better for sure, but worth double the price... no.  But no alternative either.