My initial look and analysis of the iStreamer DAC for i-devices. http://youtu.be/W6UIL7wFaHY
Beyer T51p, v-moda M80, B&O H6, B&W P7, Shure 1540, Audioengine D3/Microstreamer/FiiO E07k DAC/amps, Zen Head amp.
Nice. In terms of the audio, I wonder what's actually in the box? Going purely from the price my guess is it's a modified Streamer II, though interestingly, as you also noted, the sample-frequency tops-out at 48kHz whereas the standard Streamer II can handle 96kHz. That makes me wonder if they've used bespoke electronics just for this DAC (would seem unlikely though).
Let us know what your long-term impression of it is, compared to using the standard headphone output.
Main system: Mac Mini 2011 > HRT II+ DAC • Cyrus 2 & PSX • Cyrus tuner • MS 10i speakers [on loan]
Also cluttering-up the place: Thorens TD160 (no cart) • Marantz CD 63 mkII KI & PM66 KI • Technics SL-P777 • Nakamichi DR-1
Watching the light on the front has been interesting. Mostly so far I've used the iPhone4s, but I plugged in the iPod Nano touchscreen edition and that seemed to work the same way. But what was interesting was seeing the light move from 44k to 32k on one track and 48k on another track. Going to 32k was not surprising given that I do have a few lowrez MP3's, but the switch to 48k was a surprise since most of my 320k CBR MP3's play at 44k, and they are the highest rez tracks I have on the i-devices. So how the iStreamer is able to detect the difference between 44khz and 48khz on 320kbps MP3's is something I'll have to investigate.
What's very peculiar with this iPhone digital output is that the EQ settings are still active in the iPhone4s. The phone is connected to the iStreamer DAC via USB and the iStreamer is reporting a 44 khz signal on the front panel. The iStreamer is connected via its output to the O2 headphone amp which is feeding the Shure 1840 headphone. I don't see how the tone controls/EQ settings could be active from the iPhone through the iStreamer DAC to the headphone amp when the iPhone is supposed to be providing a digital signal only to the iStreamer.
Hi Dale, the EQ is digital, just as it is in such as iTunes or audio-editing software like Audacity etc. If you want a 'flat' signal sent to your iStreamer (which I would highly recommend for reasons I'm happy to bore you with on request), turn off the EQ.
I added the full text review on the Stereophile site. It explains some of what I found, and why EQ is sometimes a necessary evil.
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