[elfary]

Actually the 4G Touch measured output impedance is about 7 Ohm which is the same for the 3G Touch. Since that impedance has been measured by two different guys i think it's pretty safe to assume that the number is ok and in my view is consistent with Markus FR graphs.
 
The current Classic has a Z out of 5 Ohms (http://sonove.angry.jp/ipodclassic6th.html). The unit measured is the model MC297 (Current model even if the reviewer calls it 6G). Too bad Markus measured the thick Classic instead of the current model.
 
The provided link is fantastic. Thanks a lot. Out of the blue what i'm noticing is that when you go with the Apple Line Out + Amp path you get better FR and distortion figures but you lose in exchange quite a few decibels of stereo crosstalk performance.

 

[Inks]

I wonder if the thin 120gb model will graph like the former or latter Classic. Thanks for the graphs, pretty informative stuff. I tried to go on the main site and it didn't work though. Overall seems like the Iphone 4 graphs better than all the DAPs on an ampless setup. It also seems to graph better than the Ipad 2. 

 

[elfary]

I had the 120 gb Classic and its hp out was audibly worse than the current 160 model.
What has struck me the most has been to find out that the iPod Touch is the worst sounding model of the Apple catalogue having 7 ohms of output impedance vs the 1 ohm of the iPhone 4, 2 ohm of the current nano and 5 ohms of the current Classic.Thus with balanced armature iems the Touch is the worst choice. It's worlds apart from the iPhone 4 which i would have never suspected.

 

[JeffInCO]

Anyone noticed weak bass with Sennheiser HD280 Pro's and the iPhone4?  I've had the headphones much longer than the phone (6 or 7 years now), and have always been quite happy with the 280's when driven by other sources.
 
I started googling to see if I could find anything out there about the iPhone 4's headphone output.  I.e., impedance, frequency response, etc.  I stumbled on this forum as it seems to be one of the few places where this sort of thing is discussed.  Looks like its output impedance is impressively low, based on the last few posts in this thread.  Anyone know if the iPhone 4's headphone output is capacitively-coupled?
 
The HD280 Pro's are nominally 64-ohm.  Haven't seen an impedance curve for them, though.
 
I've never seriously considered a headphone amp, but maybe the iPhone 4 needs a little help with the HD280's?
 
Anyone else have any experience with this combination?  Any recommendations on an amp?
 
Thanks,
 
Jeff
 

 

[b0ck3n]

Low output impedance = higher damping, which leads to tighter bass control. More "true to design", but not necessarily to your liking. That's my best guess anyway.
 
EQu is a fairly decent parametric EQ app that you could try out.

 
Quote:

Anyone noticed weak bass with Sennheiser HD280 Pro's and the iPhone4?  I've had the headphones much longer than the phone (6 or 7 years now), and have always been quite happy with the 280's when driven by other sources.
 
I started googling to see if I could find anything out there about the iPhone 4's headphone output.  I.e., impedance, frequency response, etc.  I stumbled on this forum as it seems to be one of the few places where this sort of thing is discussed.  Looks like its output impedance is impressively low, based on the last few posts in this thread.  Anyone know if the iPhone 4's headphone output is capacitively-coupled?
 
The HD280 Pro's are nominally 64-ohm.  Haven't seen an impedance curve for them, though.
 
I've never seriously considered a headphone amp, but maybe the iPhone 4 needs a little help with the HD280's?
 
Anyone else have any experience with this combination?  Any recommendations on an amp?
 
Thanks,
 
Jeff
 

 

 

[JeffInCO]

I suppose the higher damping is a possibility... but I've listened to my 280's on everything from tiny Sandisk MP3 players to 100 W/channel mid-range home stereo equipment -- I've always liked what I heard. 
 
I'm not a "bass head"; I've never felt the need to EQ the 280's before.  I like the 280's controlled (not boomy) bass.  It just sounds like the audio is being high-pass filtered on the phone.  The really low frequencies are attenuated.  (I have the iPhone's iPod app EQ turned off, by the way.)
 
Anyway, I guess it's time to do a few experiments with the iPhone and various amplifiers that I already own.
 
Thanks,
 
Jeff
 
 
 

 

[b0ck3n]

I linked a database of measurements where some are of the iP4 in various set-ups, no sign of rolled off bass - it should be dead flat with all but the wildest impedance headphones.

Good luck with your experiments.

 

[my2crazy]

Saw this thread, not really interested myself but I thought I would report on this. My wife has an iphone 4, I have an ipod touch 2nd gen I compared it to. I listened to several songs from tool from 320 kbs Mp3s (yeah not the best *shrugs*) and I used my Grado SR80s to keep going back and forth over the same parts of songs at the same volume levels. I am not an experienced audiophile but...it seemed to me that the iphone 4 had slightly more bass but that it just didn't have the clarity that made it feel that the band was in the room with me. In one song there is a baby crying before the song starts and on the 2nd gen you can hear the space in the room and on the iphone 4 it felt very one dimensional. I plan on getting a cowon j3 later and when I do I will post something about another comparison using flacs between the iphone 4, ipod 2nd gen and j3. (all directly out of headphone jack)
 
I bought one of the EQ apps for the touch...and I was upset that my 2nd gen wouldn't run it. Just a warning. (it was incredible on the iphone 4, but I barely played with it and did not do any comparisons using the EQ) Private message me if you would like to ask me anything, I probably wont be able to check back in to this particular thread for awhile.
 
Edit: I would like to add that this difference was hard for me to notice, and I had to go back and forth quite a bit.

 

[Inks]

To me the IP4 sounded much better than the Ipod Touch 2G. I used many IEMs of different impedances, Touch 4g fared better but still slightly inferior. 

 

[jasonb]

Quote:

Something they didn't fix is the large volume steps.

this can also be fixed by jailbreaking and installing MyVolume from the Cydia app store. it can (up to) triple the amount of steps in the volume control. going from 15 steps to 45 steps is quite nice. 
 
i am quite happy with the headphone out into my Sleek Audio SA6 IEM's. i might eventually grab a Fiio L9 to try with the E5 that i have but never use. i am usually never any higher than the 2/3 mark on the headphone out though so im not sure its worth it to even bother. 

 

[my2crazy]

Over the last month or so I keep seeing a recurring theme with the Iphone 4. Here in Tokyo Softbank is giving them out for free if you start a data plan so tons of people have them. Come to find out, they break very very easily. It is normally that the screen cracks or shatters due to dropping, sitting on, placing in pocket with something else ect. Sometimes it is the back plate that breaks, but not as often. These screens are expensive to get fixed depending on your insurance, technical knowledge, ect. I have dropped my ipod touch 2g and other ipods more than I should admit to(I am really tough on devices)...and none of them have broken yet. I now have to either pay like 250 dollars to get my wife's iphone 4's screen fixed or buy one for about 100-150 dollars and replace it myself...at some risk to the phone/player. 
 
My boss has broken 2 of them, at least 4 of my other coworkers have broken theirs as well. I have talked to 2 neighbors who have also broken theirs.
 
If you plan on getting the iphone 4, get a very protective case for it and treat it carefully.

 

[SoupRKnowva]

 
Quote:

Over the last month or so I keep seeing a recurring theme with the Iphone 4. Here in Tokyo Softbank is giving them out for free if you start a data plan so tons of people have them. Come to find out, they break very very easily. It is normally that the screen cracks or shatters due to dropping, sitting on, placing in pocket with something else ect. Sometimes it is the back plate that breaks, but not as often. These screens are expensive to get fixed depending on your insurance, technical knowledge, ect. I have dropped my ipod touch 2g and other ipods more than I should admit to(I am really tough on devices)...and none of them have broken yet. I now have to either pay like 250 dollars to get my wife's iphone 4's screen fixed or buy one for about 100-150 dollars and replace it myself...at some risk to the phone/player. 
 
My boss has broken 2 of them, at least 4 of my other coworkers have broken theirs as well. I have talked to 2 neighbors who have also broken theirs.
 
If you plan on getting the iphone 4, get a very protective case for it and treat it carefully.

thats strange, cuase i dont have a case at all, i hate cases, they add unecessary bulk and ruin the design. and ive dropped mine several times, and all ive got to show for it is some dents in the outer ring of the glass, and these drops were on asphalt...
 

 

[my2crazy]

Quote:

 

thats strange, cuase i dont have a case at all, i hate cases, they add unecessary bulk and ruin the design. and ive dropped mine several times, and all ive got to show for it is some dents in the outer ring of the glass, and these drops were on asphalt...
 

I wonder if the Iphone 4 we are getting here is from a different manufacturing plant, or maybe it's just a semi unlikely break that is common just because there are so many people running around with the phone.
 
 

 

[MoSXS]

iPhone 4 owner since day one here. I've either had my iPhone "naked" or using the free bumper case. Device is as close to mint condition as it can be. Even had it knocked out of my hand and it fell face down and flat on concrete while using the bumper case. Not a mark on it. You'd have to be extremely rough with it to mark it, let alone break it. Extremely rough.

 

[phntmsmshr]

iPhone4's inbuilt iPod suffers from the same issues as every other iPod in terms of rubbish EQ. Since the introduction of third-party EQ players though, I've completely eliminated the need for any external amplification through playing with settings on EQu/Equalizer/EQ10. If only iPod Classic could get one...