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RMAA results for iPod Classic, Galaxy Nexus, FiiO E7
skamp
post Apr 26 2012, 20:58
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Here are the RMAA results for the iPod Classic (2009), the Samsung Galaxy Nexus, and the FiiO E7. The iPod was tested via it's Line Out Dock, as well as its headphone out, unloaded, and loaded with Sony MDR-XB700 headphones (24 ohms). The Galaxy Nexus and E7 were tested via their headphone out, loaded and unloaded. Here's a comparison between the 3, loaded with the headphones.

Audiophiles always say that the iPod's LOD outputs a "cleaner" signal than its headphone out; if I'm reading the values and graphs right, that seems correct. I couldn't say whether the difference is audible; one would have to also test the external headphone amplifier that would be connected to the LOD.

Overall the E7 seems superior, while the iPod is a pretty close second in some aspects, especially if you consider the LOD results. Of note is the significantly worse stereo crosstalk result from the Galaxy Nexus.

Edit: I used an old laptop for the recordings. I'm considering investing in a decent USB device. If I do get one, I'll run RMAA again.

This post has been edited by skamp: Apr 26 2012, 21:09


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skamp
post Apr 26 2012, 21:37
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Group: Developer
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The volume cap can't be removed. How does the volume of the recording affect the results? I didn't match the volumes. Are my results useless?

Here's some better results. Obviously my SNR and noise measurements are completely off. I'll run a corrected test later.

This post has been edited by skamp: Apr 26 2012, 21:54


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saratoga
post Apr 26 2012, 21:52
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QUOTE (skamp @ Apr 26 2012, 16:37) *
The volume cap can't be removed.


Sure it can. I know for a fact that we don't implement it in rockbox, since i reviewed some of the patches for the ipod 6G's sound driver smile.gif

QUOTE (skamp @ Apr 26 2012, 16:37) *
How does the volume of the recording affect the results? I didn't match the volumes. Are my results useless?


The frequency response will be unaffected, but it will probably make everything else look worse by about however many dB its capped. Both because they will be worse, and because your sound card will probably struggle to record such weak signals without introducing more noise.

That said,

QUOTE (skamp @ Apr 26 2012, 16:37) *


.. those are a lot better. I tend to think that the system you recorded with actually has a higher noise floor then the devices you were testing so maybe the SNR results aren't going to be right regardless. Still, good to know all of the devices you tested have very high SNR smile.gif
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Posts in this topic
- skamp   RMAA results for iPod Classic, Galaxy Nexus, FiiO E7   Apr 26 2012, 20:58
- - saratoga   You said in the other thread that you've got t...   Apr 26 2012, 21:29
- - skamp   The volume cap can't be removed. How does the ...   Apr 26 2012, 21:37
|- - saratoga   QUOTE (skamp @ Apr 26 2012, 16:37) The vo...   Apr 26 2012, 21:52
- - skamp   Thanks. I guess I'll just suck it up and buy a...   Apr 26 2012, 22:16
- - skamp   Well, I dusted off my old PC and tried three diffe...   Apr 27 2012, 09:41
|- - Arnold B. Krueger   QUOTE (skamp @ Apr 27 2012, 04:41) Well, ...   Apr 27 2012, 12:16
- - skamp   And, lo and behold, my wonderful Asus N75SF laptop...   Apr 27 2012, 12:30
|- - stephan_g   QUOTE (skamp @ Apr 27 2012, 12:30) And, l...   Apr 29 2012, 21:28
- - saratoga   Could you put those galaxy nexus results back up? ...   Apr 30 2012, 17:06
- - skamp   I deleted the old results, there were obviously of...   Apr 30 2012, 19:00
- - saratoga   What happened with the frequency response on the G...   Apr 30 2012, 19:02
- - skamp   The GN always had a slight treble roll-off. I test...   Apr 30 2012, 19:09
- - saratoga   You must be right. I'm probably confusing thi...   Apr 30 2012, 19:40
- - skamp   Results with Denon AH-D1100 headphones (32 ohms) a...   Apr 30 2012, 20:59
- - skamp   I installed Rockbox on my iPod last night. I updat...   May 2 2012, 11:21
- - nevermind   Those measurements look a bit strange for the ipod...   May 4 2012, 03:44
|- - Arnold B. Krueger   QUOTE (nevermind @ May 3 2012, 22:44) Tho...   May 8 2012, 13:39
- - skamp   All tests were run on battery. Note that the lobes...   May 4 2012, 10:12
- - stephan_g   These lobes seem to be an artifact introduced by R...   May 5 2012, 12:51
- - skamp   I got an EMU 0204 USB and made new measurements. I...   Dec 7 2012, 09:46
|- - Arnold B. Krueger   QUOTE (skamp @ Dec 7 2012, 03:46) I got a...   Dec 7 2012, 15:05
- - skamp   On second thought, I'm not sure my stereo spli...   Dec 8 2012, 23:10
- - saratoga   Crosstalk depends on current, so if you drive a hi...   Dec 8 2012, 23:33
- - IgorC   Skamp, Interesting measurements. I'm very sur...   Dec 9 2012, 04:30
- - skamp   Well, the EMU shows a 0.5 dB bump at 30 Hz, but th...   Dec 9 2012, 11:51
- - skamp   I followed these instructions and I measured the o...   Dec 10 2012, 14:58
|- - elfary   This thread is really interesting for me. As a us...   Dec 14 2012, 11:05
|- - skamp   QUOTE (elfary @ Dec 14 2012, 11:05) Hence...   Dec 14 2012, 18:03
|- - elfary   QUOTE (skamp @ Dec 14 2012, 18:03) QUOTE ...   Dec 14 2012, 20:05
|- - skamp   QUOTE (elfary @ Dec 14 2012, 20:05) Thank...   Dec 15 2012, 11:05
- - skamp   I just got a Fuze+, it's pretty nice. I didn...   Feb 25 2013, 22:19
- - mzil   Thanks for posting that. RegardingQUOTE There...   Feb 25 2013, 23:45
- - skamp   I realize that statement was ambiguous. Actually t...   Feb 26 2013, 00:01
|- - Arnold B. Krueger   QUOTE (skamp @ Feb 25 2013, 18:01) I real...   Feb 27 2013, 11:28
|- - skamp   QUOTE (Arnold B. Krueger @ Feb 27 2013, 11...   Feb 27 2013, 11:49
- - skamp   It's strange that the noise and dynamic range ...   Feb 26 2013, 00:08
- - saratoga   Depending on what you are doing the voltage and cl...   Feb 27 2013, 16:57


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