Phelonious Ponk
100+ Head-Fier
- Joined
- Apr 22, 2009
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...ok, an admittedly over-dramatic thread title, but really, this is pretty revealing stuff. Here on Head-Fi, it is pretty much common belief that the best performance comes from high-end sources, that expensive, even relatively inexpensive outboard DACs are better than the ones that are built into common consumer audio devices and that the big high-impedance phones require outboard, AC-powered amplification to reach beyond the giddy heights of mediocrity. My ears always told me most of that was wrong, though I suspect that most high-impedance phones are also low efficiency and do, at least, require sufficient headroom. The rest of it? You may not be able to listen to numbers, but it's nice when they confirm what you're hearing.
That kid bobbing his head next to you on the bus? If he has some good ear canal phones he may be doing better than your high-end system...
Quote:
...and now we anxiously await the denial...
P
That kid bobbing his head next to you on the bus? If he has some good ear canal phones he may be doing better than your high-end system...
Quote:
| "Apple claims a 20–20,000 Hz response for the iPod Touch. No distortion or level-dependent information is shown in the literature supplied with the iPod. To perform the following tests, I imported the CBS Records CD-1 into iTunes in Apple Lossless format. After connecting the iPod, the Syncing process placed the CD onto the iPod. The iPod's headphone jack was then connected to my computer-based audio analysis software, SpectraPlus (a PHS product that retails for $295–$1295, depending on selected options). SpectraPlus provided a complete spectral analysis of the iPod's audio signal." To my surprise, the iPod Touch did very well in the tests. All tests were run on a fully-charged battery, and the iPod's volume control was set to maximum. The audio signal from the iPod fed my desktop computer's E-mu 1616M PCI outboard converter. A 30 kHz low-pass filter was used in the tests. Maximum Output and Distortion: The maximum output and distortion with no load at 1 kHz was 1.04 dBV rms and 0.009% THD. The numbers did not change for loads between 300 to 600 ohms. The unit is easily able to cope with most headphone impedances because the output impedance approaches the ideal, 0.9 ohms. The S/N ratio was –79.5 dB. At a more likely 0.5 dBV rms output level, the distortion was 0.014% and the S/N was –76 dB. The 2nd through 5th harmonic distortion components never exceeded –75 dB. The IMD was 0.008% using the IM standard 60 and 7,000 Hz tones. Frequency Response at 0.75 dVB rms output, both channels into 300 ohms: 17–16,000 Hz was flat. Between 18–20 kHz the unit was down 0.1 dB, excellent. The highest THD occurred at 12.5 kHz, –55.5 dB, good. Channel separation was typically –50 dB, OK. The output imbalance between channels never exceeded 0.7 dB at 18 kHz, good. Square Wave Performance: A small ripple was visible, typical for A/D converters. The ringing occurred at the leading edge of the 1 kHz square wave, very good. .. The Touch presents a nearly distortion-free signal to almost any headphone." http://www.bostonaudiosociety.org/foster/index.htm"][/URL] |
...and now we anxiously await the denial...
P
