![]() ![]() Peak jitter from 50 Hz to 100 kHz is about 1.25 nanoseconds on the digital optical output. The average jitter from 700 Hz to 100 kHz is about 280 picoseconds on the digital optical output. These numbers are but one indication of sound quality. Warning: The following jitter numbers should not be used as the only indicator of the AirPort Express' performance. 24 bit Walking Zero was truncated to 16 bit. Both 16 bit DC and Walking Zero tests were bit true as well. The phase remains correct even with bit truncation from 24 bits to 16 bits. All 24 bit content is truncated to 16 bits. All other sample rates including 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz, and 192 kHz are converted to 44.1 kHz. Second Generation AirPort Express - WAV, AIFF, Apple Lossless, MP3, and AAC files at 16 bit / 44.1 kHz are bit perfect (without data loss) from iTunes to the AirPort and through the AirPort's optical output. Peak jitter from 50 Hz to 100 kHz is about 1.52 nanoseconds on the digital optical output. The average jitter from 700 Hz to 100 kHz is about 474 picoseconds on the digital optical output. The AirPort Express always sent out the same status bit and Copyright bit. Playback of the same test tone at 176.4 kHz and 192 kHz displays severe distortion as the sample rate converter is overdriven. Playback of a 997 Hz test tone measured at the digital output of the AirPort Express displayed a bit higher noise at 48 kHz. As such I have used wording directly from the testing lab in many instances.įirst Generation AirPort Express - WAV, AIFF, Apple Lossless, MP3, and AAC files at 16 bit / 44.1 kHz are bit perfect (without data loss) from iTunes to the AirPort and through the AirPort's optical output. ![]() I've attempted to explain some of the results in general terms but many of the results are far too complex for simple explanations. Readers should know that I am not capable of performing the tests or analyzing the results without an extraordinary amount of help from the testing lab. This was the last production version of the first generation model. The first generation AirPort Express used in these tests was purchased after the release of the second generation unit. Testing was conducted by an independent lab using Mac OS X 10.6.8, iTunes 10.6.3, optical digital output, and analog output from the AirPort Express into an Audio Precision analyzer. Second Generation AirPort Express model number A1392, serial number C86HT2TVDV2R running firmware version 7.6.2 The time has come to put both new and old Express units on the analyzer and publish updated measurements.įirst Generation AirPort Express model number A1264, serial number 6F149A8Y2UF running firmware version 7.6.1 Since then Apple changed critical internal parts increasing jitter levels and more recently completed a redesign of the entire AirPort Express. On June 11 at the 2012 Worldwide Developers Conference, the 2nd generation AirPort Express was introduced with a new design and dual-band support of 802.11n over 2.4 and 5 GHz networks.Seven years ago Stereophile's John Atkinson published objective measurements of Apple's AirPort Express ( Link ). Support was later added for the draft specification of the 802.11n protocol.Ģnd-generation Airport Express 2nd generation Airport Express can also be used to easily expand wireless coverage via WDS-bridging. Audio-out supports digital optical and analog output. Now called AirPlay, the functionality requires iTunes 4.6, or newer. Airport Express supports AirTunes, which allows audio to be streamed over wireless network to the Airport Express, which then outputs the audio through its audio-out to stereos, for example. Much smaller than the full-sized AirPort Base Station, it held the title for the smallest AirPort router in existence, and included audio-out, USB for wireless printing, and an ethernet port. The original Airport Express used the 802.11g specification.
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