[BobMonkhouse]

I wouldn't return a car only because the engine needs a few thousand km before it starts performing its best as long as I'm informed it's normal.

 

[loregnum]

That's the main problem with demo units.
Second, i'll return them.
Just my opinion.

If i'm going to pay that amount of hard earned money, i don't want to adjust myself/ the headphone to my likings.
If it's a known "issue" of some headphones, i'll give the advice to be "burned in" by the manufacturer.

Such "burn in" did not happen with my Era-1. ( let me fool myself this way ^^ )
No difference between the demo unit and my purchased one.

Alais, that's my opinion and i didn't want to bother one of you.
Everyone acts differently.

Have a great day and keep listening.

For what it's worth, I don't notice any difference with my A2Cs now 100+ hours in than when I got them. If there was actually any burn-in effect, it must have happened within a couple hours after using them. If by chance there has been a burn in effect and it's been longer than that, it's obviously been so minor that I have not noticed it happening over the 100+ hours. Not been a case where I got them and thought

"wow, these have issues!"

and then now think

"these are great!"

They've sounded great to me the entire time.

 

[Chris Kaoss]

I wouldn't return a car only because the engine needs a few thousand km before it starts performing its best as long as I'm informed it's normal.

Sure, this example is well choosen.
But that means the car works as intended.

Anyway, i don't judge by the first seconds.
We all know well that our brain is misleading us in many ways.

It's not on me to reject them before i got a listen.

 

[PointyFox]

I constantly experience brain burn in. I think everyone does especially when switching to very different sonic signatures. Kind of similar to this, but with sound :

The shapes in the middle are the same color. Your senses adapt based on external information such as memory of the sound you heard prior.

 

[DangerToast]

I bought a pair of AF2C at Can Jam NYC after hearing a pair that the nice dude from Dan Clark Audio said wasn't burned in yet. Still sounded great to me. After 11 days of heavy use as well as leaving it plugged in with some music playing overnight a few times, I can't tell any difference. It still sounds great! Over two years of extremely heavy listening on the original AC, I would say there were only very minor changes with burn-in. Maybe a veeeery slight widening of the sound stage and improvement with naturalness. This is all incredibly subjective, of course.

Also I'm loving this headphone. It sounds effortless coming from my Bifrost MB into a Lyr 3. It sounds incredibly exciting (maybe even a slightest bit fatiguing) coming from my ifi iDSD black label. Don't read too much into the fatiguing thing because I'm not using any dampening and blowing out the treble with the 3D+ switch on the black label. It hurts so good!

 

[menuki]

I bought a pair of AF2C at Can Jam NYC after hearing a pair that the nice dude from Dan Clark Audio said wasn't burned in yet. Still sounded great to me. After 11 days of heavy use as well as leaving it plugged in with some music playing overnight a few times, I can't tell any difference. It still sounds great! Over two years of extremely heavy listening on the original AC, I would say there were only very minor changes with burn-in. Maybe a veeeery slight widening of the sound stage and improvement with naturalness. This is all incredibly subjective, of course.

Also I'm loving this headphone. It sounds effortless coming from my Bifrost MB into a Lyr 3. It sounds incredibly exciting (maybe even a slightest bit fatiguing) coming from my ifi iDSD black label. Don't read too much into the fatiguing thing because I'm not using any dampening and blowing out the treble with the 3D+ switch on the black label. It hurts so good!

Please take care of your ears though! Tinnitus can be non-reversible. I realized that I listen to the AF2C's on too high volume more than I'd like to admit as well.. just because they sound so darn good and there is not even a hint of distortion. Also, if the treble hurts a bit, why not simply insert one of the black or even white filters? By the way since I'm curious, can you put into words what the 3D+ Switch does to the sound? Widen the stage probably? More space arround instruments? Does it work with every track?

 

[menuki]

My experience was exactly opposite. The treble is extremely, extremely harsh. And the treble imbalance is not the only problem, the whole sound crazily distorted and congested.
I must be missing something. The Mojo is the problem ?

Seriously, I almost begin to believe that something is wrong with the AC2's you're listening to. Listening to almost any track the treble never gets into harsh territory. It might seem like that coming from a headphone with recessed or overly smooth treble, but I don't have any problems and as mentioned I consider myself treble sensitive. You mentioned you couldn't hear vocals very clearly? That makes me think even more that there's something wrong with them since the vocals are clear as a bell usually. I'm not sure - the Mojo may also be a colder source, don't quote me on that though. Overall they just shouldn't sound distorted, at all - distortion levels looking at measurements are very low as well, so maybe connect them to a different source to see what happens?

 

[BobMonkhouse]

I totally acknowledge and take in consideration my brain burn-in. When I switch listening to two or more headphones I need to adapt to the the different signatures. If I adjust to the new music representation quickly and don't wish switching back to the previous headphones pair, I know I like what it's offering.

 

[DangerToast]

can you put into words what the 3D+ Switch does to the sound? Widen the stage probably? More space arround instruments? Does it work with every track?

I'm not sure I'm going to do such a good job but I'll do my best. I'll start by saying the 3D+ feature on the ifi iDSD BL is a fun and enjoyable bonus to an already exceptional product. In other words, it's cool! Others have described it as injecting a little bit of a "balanced" feel into a single-ended source. I think it goes a little beyond that, in a fun and completely not neutral way. It blows out the sound-stage to a degree which, depending on the source, can either be extremely engaging or horribly distracting. Imagine the HD 800 sound-stage on steroids. For high quality stuff that's well-mastered, this can be an awesome, different experience. For crummier stuff it just turns your music into sound-soup. Also, the 3D+ feature works better on higher-end headphones. The AF2C is the most expensive pair of cans I own, and they know what to do with the 3D+. My old, trusty DT770 pro, which I love, has absolutely no idea what to do when I flip the 3D+ switch IMHO. In addition to the sound-stage increase, I think treble becomes a little more sparkly and, at times, and depending on the track, intense and fatiguing. But it's also incredibly engaging. If you use the 3D+ and the Xbass+ switches at the same time, your AF2C goes from a pretty darn neutral and revealing headphone IMO to a v-shaped semi-automatic rifle that shoots delicious treble and bass bullets into your skull. So while I prefer to listen to the AF2C with my schiit stack, I do think the ifi iDSD BL is a good match as well. If you don't want that extra excitement added, you can just turn the Xbass+ and the 3D+ off, and you've still got an excellent portable dac/amp with tons of functionality

 

[PointyFox]

My experience was exactly opposite. The treble is extremely, extremely harsh. And the treble imbalance is not the only problem, the whole sound crazily distorted and congested.
I must be missing something. The Mojo is the problem ?

What are you comparing it to?

 

[SierraMadre]

I'm not sure I'm going to do such a good job but I'll do my best. I'll start by saying the 3D+ feature on the ifi iDSD BL is a fun and enjoyable bonus to an already exceptional product. In other words, it's cool! Others have described it as injecting a little bit of a "balanced" feel into a single-ended source. I think it goes a little beyond that, in a fun and completely not neutral way. It blows out the sound-stage to a degree which, depending on the source, can either be extremely engaging or horribly distracting. Imagine the HD 800 sound-stage on steroids. For high quality stuff that's well-mastered, this can be an awesome, different experience. For crummier stuff it just turns your music into sound-soup. Also, the 3D+ feature works better on higher-end headphones. The AF2C is the most expensive pair of cans I own, and they know what to do with the 3D+. My old, trusty DT770 pro, which I love, has absolutely no idea what to do when I flip the 3D+ switch IMHO. In addition to the sound-stage increase, I think treble becomes a little more sparkly and, at times, and depending on the track, intense and fatiguing. But it's also incredibly engaging. If you use the 3D+ and the Xbass+ switches at the same time, your AF2C goes from a pretty darn neutral and revealing headphone IMO to a v-shaped semi-automatic rifle that shoots delicious treble and bass bullets into your skull. So while I prefer to listen to the AF2C with my schiit stack, I do think the ifi iDSD BL is a good match as well. If you don't want that extra excitement added, you can just turn the Xbass+ and the 3D+ off, and you've still got an excellent portable dac/amp with tons of functionality

Hi. Do you have the HD800? If so, does it pair well with the ifi? I have the HD800S’s and will shortly be getting the Aeon Open 2’s and am looking for a warmish amp or dac/amp that can serve both well but in particular tame the HD800S treble and bring out more of the low end for a smoother, more laid back sound and with a bit more bass presence rather than having to rely on EQ as I do with my current equipment (Massdrop THX AAA).

Many thanks in advance

 

[mrspeakers]

Mojo is known as a warm source. But the treble was still extremely harsh and enouh to completely ruin the sound. Even more harsh than the Beyerdynamic headphones known for their massive treble peaks.
We almost certainly listen to different music pieces so this may be causing the different experiences.
I will definetly try it with different amplifiers though. Let's see what happens

If I recall you said you heard this at a dealer. Since you have a dealer there's little point having head-fiers guess a solution when we can be precise with little effort. Let me know the dealer so we can contact them to make sure everything is OK with their system, please PM me their name, your contact info and name so we can have the dealer follow up with you after we've verified things.

 

[ubs28]

So if the AFC 2 has a nasty treble peak, it is defective?

Mine definety also has it.

 

[menuki]

a v-shaped semi-automatic rifle that shoots delicious treble and bass bullets into your skull.

Awesome. Thanks for sharing your experience, really interesting. The quote above got me curious I have to admit. Might try one of the Micro or Mini devices from iFi as well and compare them with my Hip-Dac. Definitely also curious how that mode would sound with classical music.

 

[menuki]

So if the AFC 2 has a nasty treble peak, it is defective?

Mine definety also has it.

Are you using any inserts? Is the white felt for example enough to reduce the peak to a bearable level? Mostly just interested since I had many headphones with nasty treble spikes before, but I thankfully don't consider the A2C's one of them.