2. digital
  3. 132394-12382

Chromecast Audio

I have mentioned the Chromecast Audio a few times as a viable streaming option. Its biggest advantage apart from the very low price is that unlike with dedicated streamer units from more expensive brands, there are apps for just about any streaming service. Moreover, sonically there is little wrong with it. Its internal DAC is pretty good, and I think good enough for 16/44 reproduction. Right now, I am using it with my Quad electrostats and I have no reason to complain. But if you want the best from it, a first rate external DAC might use the digital output for just possibly a better sound. See here for some tests of both the digital and the analogue output: http://archimago.blogspot.nl/2016/02/measurements-google-chromecast-audio_27.html
However, that was only by way of introduction. What I really wanted to discuss is the so called high dynamic range option for the analogue output. Of course we all like high dynamic range, so this seems like the one to choose. However, if you choose this option a higher dynamic range is not really what you get. It has now been shown that the dynamic range does not change, but what changes is the output level. ’High dynamic range’ is about 2V, i.e. the same as the Red Book CD standard. Standard output is some 1,2V. The implication is that for many people the standard output is the better choice, unless your pre amplifier’s input sensitivity is low enough to handle 2V without clipping. Since there are many amplifiers that are not comfortable with such a hot signal, my advice would be to think hard before you opt for the stronger signal.
willemj
soma70
153 posts
 
Willem. Thanks for your link to the chromecast analysis at Archimago on the iPhone 7 discussion. I thought I would reply here so as not to hijack that thread. Archimago is not a website I had come across and clearly the writer knows their stuff whilst also remaining open to new evidence and peer review. Very refreshing. I have since read a lot of the other pieces on the site and enjoyed them as well and this has given me another perspective to consider, so thanks again. I still can’t agree that the DAC inside chromecast is any good though!! 😄

kalali's avatar
kalali
1,977 posts
 

"...unless your pre amplifier’s input sensitivity is low enough to handle 2V without clipping."

Thanks for the link. How do you compare streaming music using iPhone analog output -> to preamp vs. Streaming via Chromcast -> preamp?

I’m however not sure if I follow the statement I pasted above. If I’m not mistaken, the 2V is the industry (I think THX) standard for unbalanced analog output for most if not all digital source equipment and the downstream components, preamplifiers in particular, should all be able to handle this level without clipping. Actually, I don’t even recall seeing input sensitivity specs - assuming you meant input voltage sensitivity, not input impedance, even mentioned in preamplifier data sheets. However, the concern around input voltage sensitivity can come into play for power amplifiers, and is usually published, since a very low input voltage sensitivity, as defined by the voltage to deliver maximum output, could cause overload when presented with the nominal 2V input, e.g., an amplifier with a 0.5V sensitivity, etc. Makes sense?

More to discover