Okay, okay. I’ve seen a lot of audio player enabeld phones review. But, most of them only evaluate the phone functionality, audio player interface, and etc… etc. I know that sound quality tends to be subjective (tested with ears), but it’s not a bad thing if we test the objective quality (tested with equipment), right?Few weeks ago, I borrowed two phones. One was the Nokia N91 and the other is Sony Ericsson W810i. Two are audio player enabled phone. So, let’s evaluate them.

For introduction, I don’t use sophisticated equipment like Audio Precision. It’s just a software named RMAA and a sound card as D/A. I have few cards like EMU 1820M and ESI Juli@. Both are professional cards. But for this test, I just use prosumer card the M-Audio Revolution 7.1. This card has flat enough response (+0.13, -0.07 dB, and >90 dB of noise, dynamic range, and stereo crosstalk @ 16bit/44.1 kHz). If possible, I will re-test with my EMU or Juli@, but I believe the result will not be different. The RMAA is well know an excellent software for this purpose. One time, the creator had done comparison with Audio Precision and the result was quite similiar. So, we simply can trust this software 😉

So, let’s start with overall frequency graph.

The graph above is the frequency response of N91 (white) and W810i (green).
* The N91 has little ripple than W810i, but the overall response is not so extend. The low only reach 20 Hz and sharply down below it. The frequency is raising after 20 Hz and back to 0 dB at 300 Hz. This will give extra sensation in low and mid-low frequency. Some bass instruments should have more body in N91. From 7 kHz to 19 kHz, N91 has few ripples less than 0.5 dB. Most people will not realize this problem.

* The W810i has more ripple especially in high extension. Its low extension is excellent. She reaches 8 Hz before roll-off sharply. A lot of ripples around 0.1-0.2 dB are found in most mid to high band on W810i. Started from 10 kHz, the ripples are started to get stronger to 0.4-0.5 dB. Again, this may not heard by most people. The high extension of W810i is wider than N91.


The graph below is zoomed version of low frequency segment.

In zoomed graph above, we can see that the W810i has low extension down to 9 Hz, while N91 only to 22-24 Hz. Not many headphones are able to produce such low frequency, but simply W810 has advantage here. On low band, we can see that W810i has flatter response (though with more ripples). The N91 boosts the low from 20-300 Hz to gain extra “thump” bass sensation. After 300-330 Hz, the frequency back to normal (0 dB reference level). N91 also has less ripples.

The graph below is zoomed version of mid frequency segment.

Both devices perform quite similiar. But again, W810i shows more ripples though in small value. N91 has one significant dip at 9-10 kHz (around 0.4 dB).

The graph below is zoomed version of high frequency segment.


At high frequency, the result is still similiar. W810i is still showing a lot of ripple while the N91 is quite calm. W810i has advantage on wider bandwidth (on 20 kHz @ -1.5 dB), while N91 has less bandwidth (already reach -2.5 dB at 19 kHz). I don’t think many standard headphones are capable to >19 kHz, but there’s no harm of having wider bandwidth 😉

Conclusion:
They both perform very good in terms of audio quality. Nokia N91 has advantage on smoother response, but smaller bandwidth. On the other side, Sony Ericsson W810i has wider bandwidth, but with more ripple. I don’t discuss their subjective audio quality since I believe most sites have done that for you. But for most people, I believe they both will perform as good as you can get from an audio player. Provide it with good headphones and you are ready to rock.

In terms of an audiophile grade system, this is far from good. Take a look at graph below or check my other post about sound card comparison test.

The picture above is Lynx L22 sound card frequency response. This is a profesional sound card that will cost you around $500-600. See how flat she will sound (only +0.01 and -0.01 dB deviations, very-very smooth). Okay, flat isn’t everything, but I don’t mind to have flat audio player 😉