[krismusic]

With all the talk about issues with clicks on the 6S ( which mine doesn't seem to suffer from) I have kind of lost track. What is the consensus on the performance of the 6S as an audio player? Does it still measure up well against high end DAP's?

 

[watchnerd]

I don't have any issues, and, on the other end of the spectrum, the 6S with a mic through the Thunderbolt port is an awesome field recording device.

 

[briskly]

Some measurements here. Link.
 
Competent enough, besides the slightly too high output impedance for some crossover fitted IEMs, at 3 ohms. Measurements are pretty typical for the line.

 

[krismusic]

Thank you for the replies. My real question is, according to specs could I expect any significant change to the sound by using an external DAC/amp?

 

[castleofargh]

Thank you for the replies. My real question is, according to specs could I expect any significant change to the sound by using an external DAC/amp?

you must realize that this is a false question. of course there will be some DACs and some amps that will outperform the Iphone. and of course there will be some IEM/headphones that will challenge the Iphone and would work better with a better suited amp. 
if you don't set the conditions clearly enough, and the margin of progress you're expecting, we can say yes, or we can say no, and be wrong each time.

 

[krismusic]

you must realize that this is a false question. of course there will be some DACs and some amps that will outperform the Iphone. and of course there will be some IEM/headphones that will challenge the Iphone and would work better with a better suited amp. 
if you don't set the conditions clearly enough, and the margin of progress you're expecting, we can say yes, or we can say no, and be wrong each time. :wink_face:

I take your point but I was deliberately being non specific. There is a school of thought that properly designed DACs and amps should sound the same. I would be interested to know if there is anything inferior about the output of the iPhone. I'm using CIEMs so driving them is presumably not an issue.

 

[castleofargh]

nonono. when we say that properly designed amps should sound the same, we mean well powered, with a load(IEM/headphone) that isn't too hard on them, and at least a good damping ratio. which are basic nominal usage for the amps. and under those conditions, it's indeed rather easy to make a transparent amp if they decide to.
 
but when talking about portable stuff, just the power can become a problem. then the amp section is usually crap because else it would require too much power and that's not good for battery life. as they're small stuff, the circuit can't spare much space, so when plugged into a small load, the current increase will tend to make some more noise/crosstalk/disto. when will one of those become audible? it depends.  and of course the usual impedance variation from amp to amp with most multidriver IEMs.
your IE80 can make you notice hiss that almost no other IEM will make audible.
the jh13 if it's like the non phase stuff I have, will show a rather noticeable attenuation from low mid to sub as soon as the amp has a few ohm of output.
 
those stuff are not always sounding bad, but they can definitely sound different. now with a few other IEMs, almost everything sounds the same to me. that's why I don't like general statements about the superiority of one source over another one. like when people were telling how great a sony ZX1 is for example, but then you realize that it's super weak and has almost 2ohm of impedance. so I can easily find a headphone where the fiio X1 is in fact superior to a ZX1 simply because it can go almost twice as loud.
that's what I meant, we can always find a few situations where the answer to your question will be yes, and other where it will be no. the X>Y without precise conditions has little chances of being the truth.
 
now I talk like I know something, but I don't, I've never even owned an Iphone ^_^. I'm just playing the devil's advocate.

 

[krismusic]

[quote name="castleofargh" url="/t/796494/iphone-6s-measurements#post_12295076

now I talk like I know something, but I don't, I've never even owned an Iphone ^_^. I'm just playing the devil's advocate.
[/quote]
What you say makes sense and you probably know more than me.
I asked my original question because previous iPhones have "measured very well " and I wondered if that is the case with the 6S.
This is motivated by reading the Mojo thread and finding a lot of anecdote that it improves the 6S hugely. I'm sceptical and wondered if there was any technical basis for the claim. I'm probably not posting this well.

 

[watchnerd]

[quote name="castleofargh" url="/t/796494/iphone-6s-measurements#post_12295076

now I talk like I know something, but I don't, I've never even owned an Iphone ^_^. I'm just playing the devil's advocate.

What you say makes sense and you probably know more than me.
I asked my original question because previous iPhones have "measured very well " and I wondered if that is the case with the 6S.
This is motivated by reading the Mojo thread and finding a lot of anecdote that it improves the 6S hugely. I'm sceptical and wondered if there was any technical basis for the claim. I'm probably not posting this well.[/quote]

 
The amp in the iPhone is, obviously, a portable one with constraints on max voltage and current.
 
Some headphones will require more voltage or current than the iPhone can deliver.  These are poor matches and would require an external amp.
 
Other headphones, even some large ones, have voltage and current needs that are within the design specs of the iPhone and will sound good.  An external amp is just extra complication and expense in this situation.
 
That's it.

 

[krismusic]

The amp in the iPhone is, obviously, a portable one with constraints on max voltage and current.

Some headphones will require more voltage or current than the iPhone can deliver.  These are poor matches and would require an external amp.

Other headphones, even some large ones, have voltage and current needs that are within the design specs of the iPhone and will sound good.  An external amp is just extra complication and expense in this situation.

That's it.

Nice and definitive. DAC also?

 

[watchnerd]

Nice and definitive.

DAC also?

 
Not sure what you mean by "DAC also", but I'll take a guess:
 
With regard to the iPhone 6s:
 
If your headphones don't need an external amp, then you don't need an external DAC.  The digital side is good and the amp is good within design specs.
 
If your headphones do need an external amp, there may be convenience reasons to buy a combo amp/DAC if it's in one package.  But you don't need to improve the "digital side" of the iPhone 6s.

 

[watchnerd]

The simplest answer to all this, by the way, is to buy headphones that work great with the iPhone 6 "as is".  
 
I've used my 6s with big-ass AKG K271 MKII Studio headphones and it works fine; the 271 has a middle-of-the-road 55 ohm impedance and mid-high sensitivity.  My buddy's AKG K553's are even easier to drive from the iPhone and will get *loud*.

 

[krismusic]

The simplest answer to all this, by the way, is to buy headphones that work great with the iPhone 6 "as is".  

I've used my 6s with big-ass AKG K271 MKII Studio headphones and it works fine; the 271 has a middle-of-the-road 55 ohm impedance and mid-high sensitivity.  My buddy's AKG K553's are even easier to drive from the iPhone and will get *loud*.

Thanks Watchnerd. I've never felt my K10's to be struggling at all with the amp in the iPhone.
I've just been reading too much overheated talk on the Mojo thread. Needed a bucket of cold reason!

 

[watchnerd]

Thanks Watchnerd. I've never felt my K10's to be struggling at all with the amp in the iPhone.
I've just been reading too much overheated talk on the Mojo thread. Needed a bucket of cold reason!

 
It's gear porn. 

 
 
That being said, I think you can get better sound than you would from the K10 straight from the iPhone 6s, but the answer is better headphones (like the AKG K533) designed to work with mobile devices.  
 
You only need an external amp if you're using headphones that shouldn't be used with mobile devices.

 

[cjl]

Thank you for the replies. My real question is, according to specs could I expect any significant change to the sound by using an external DAC/amp?

I would feel pretty confident saying that any >30ohm headphone that is driven to an adequate level by the iPhone should be indistinguishable from the same headphone driven from a high quality external DAC/amp. If the headphone is insufficiently loud, you obviously need an external amp, and if the headphone is <30 ohms (based on the iPhone's 3 ohm output impedance), it may or may not have audible flaws, depending on how much the drivers depend on the electrical damping and depending on the impedance curve of the headphones. Even with most 16 ohm headphones, I'd expect the differences between a theoretically perfect amp and the iPhone to be subtle most of the time, but there might be some weird outlier cases.