Saturday, 22 December 2018

MUSINGS: On this Blog, Motivations, and Recent Audiophile-Targeted Articles in the "Mainstream" Press. Holiday Edition!

Hey guys & gals, grab a coffee, maybe a hot cocoa! Winter is here, at least in the North, so settle into a comfy chair by the fireplace as we head into the last days of 2018. Let's chat.

Recently, I received this comment from Museatex which I thought was a good comment and deserved a bit more discussion as a post rather than just a response which would typically be lost in the usual chatter:
Museatex 5 December 2018 at 22:59 
"Now we add the 10-year old Energy C100 speaker pair to the receiver amp. The Energy sounds similar in tonality to the rear Paradigm Studio 80's. Perhaps not surprising since both are Canadian companies using research from the National Research Council and are not far apart in age."
I haven't had such a good laugh in a while. :)
BTW I do enjoy glancing at your measurements but I am somewhat puzzled as to why you started this blog. You invest money in new sound cards/adc and not in room treatment? $15 google chromecast audio sounds to you the same as logitech transporter so why not to spend money where you can measure a real difference such as room treatment? You room is dying for acoustic treatment while you are chasing minuscule differences in digital filters you cannot hear. Why waste money on monoblock amplifiers if it is irrelevant? I mean have you compared them to $300 receiver in properly setup double blind test? ;). Please continue on doing what you are doing as I do enjoy looking at graphs at someone's else expense, though I do not understand your motivation.
Hello Museatex, good comment and in fact, it's good to discuss the big picture and motivations once awhile. To be honest, there isn't one motivation. Perhaps back in the day when I started this blog, there was a more specific intent - which at that time was just to start an online blind test to see if audiophiles could reliably hear a difference between high bitrate MP3 versus lossless FLAC compression. But remember, this is a blog. It is by nature an "online journal" of what myself and a few contributors over the years have thought worthwhile to share.

Saturday, 15 December 2018

MEASUREMENTS: Intel i7 PC and Raspberry Pi 3 B+ Audio Streamer - XLR / RCA, Noise and Jitter. Do digital transports / streamers really make a difference? Do USB cables?

This is a picture of the corner of the room where I performed the measurements for the post last week. Notice that Intel i7-3770K computer in the left corner I use for gaming? Within that box are 16GB DDR3 RAM, both a SanDisk Ultra II SSD and a recent 2TB Firecuda drive, plus a rather powerful nVidia GTX 1080 graphics processor which is what is driving the display on the 4K TV. Inside the case, it's all powered by a 6-year-old Antec 650W switching computer power supply these days. The computer is about 6 feet away from the TEAC UD-501 DAC.

Suppose I take a 16' USB cable and connected this computer to the DAC and compared the measurements with the low-power Raspberry Pi 3 B+ streamer... What do you think the result would be from the perspective of distortion and noise?

Saturday, 8 December 2018

MEASUREMENTS: Raspberry Pi 3 B+ as streamer - switching power supply, battery, WiFi, touchscreen noise??? (32GB RAM, MI: Fallout and The Beatles' 2018 "White Album")

Battery-powered Raspberry Pi 3 B+ with JustBoom Digi. Bohemian Rhapsody soundtrack.
Remember that within audiophile circles, there are often all kinds of claims about noise affecting streaming devices; especially computer-based devices. I already touched on this last week when referencing the videos by Innuos. Over the years, I had addressed software playback, different OS's, lossless formats, "need" for ethernet galvanic isolation, and explored the lack of difference between machines used for playback. In a similar way this post will also explore some "received wisdom" which seem so common among mainstream industry-supported audiophile websites.

Since I had my set-up running for last week's evaluation of the JustBoom Digi, I figure I might as well do a few more tests to demonstrate for myself (and you, fellow readers) whether these beliefs hold any truth.

Saturday, 1 December 2018

MEASUREMENTS: JustBoom Digi S/PDIF HAT for Raspberry Pi. (Plus "Why isn’t digital audio 'just ones and zeroes'?" anxiety...)

I mentioned a few months back in September that I updated my Raspberry Pi 3 B+ Touch device with the JustBoom Digi HAT for S/PDIF coaxial and TosLink digital audio output. Over the last few months, I've been using it more regularly for my nightly music listening.

As I noted previously, this device is essentially a 1-chip solution featuring the Cirrus/Wolfson WM8804 transceiver with jitter attenuating PLL (rated intrinsic jitter of ~50ps RMS) released in 2009. It also uses the Murata DA101JC isolation transformer for the coaxial output.

The device is rather plain otherwise as you can see. It does sound good and is capable of up to 24/192 with both coaxial and TosLink outputs. And at <US$40, it's also very affordable. Let's see how well it measures!