Saturday, 30 May 2015

MEASUREMENTS: Computer USB port noise, USB hubs and the 8kHz PHY Microframe Packet Noise

Block diagram of the USB 'PHYsical' chipset. UTMI stands for USB 2.0 Transceiver Macrocell Interface, a standard bus interface for the USB chipsets out there...

One could see the "glass half full" when we run into imperfections in the audio system. For example, it was serendipitous that the Emotiva XSP-1 pre-amp had such a noise-sensitive unbalanced "HT Bypass" input that I was able to detect noise and measure it previously. If it were not for this issue, I probably would never have thought about using the Corning USB 3 optical cable or consider how to isolate the noise originating from the computer USB connection to the DAC simply because in my system using balanced interconnects throughout, I had never had a problem (subjectively audible or objectively verifiable).

Saturday, 23 May 2015

Greetings from Toronto...

I've been busy over the last week in Toronto - work plus a little sightseeing and visiting with family and friends. With my hotel nearby, I managed to scoot over to Bay Bloor Radio at the intersection of Bay and Charles streets downtown to have a listen.

Tuesday, 12 May 2015

Vancouver Audio Show 2015: Pictorial & Comments...

Remember folks! Get me your "Digital Filters Test" results :-). Thanks to everyone who has already responded with the survey submission so far... Great work. Final results could be very interesting; keep the submissions coming.

Over the years I have traveled to other parts of the world and have enjoyed visiting "tech malls" as I just love technology, science, and advancement. There are huge complexes of geek-toys in Beijing (check out Zhongguancun), or of course Tokyo's Akihabara. You will find the occasional audiophile hangout at these places but admittedly rare... Not surprising I guess given how small a market for what really are luxury niche "audiophile" products (at least the "high-end" specialty shops). A few years ago I showed some pictures of Singapore's Adelphi Mall and I must say that this place still stands out as something special for the audiophile (not to mention places like SunTec and Sim Lim Square not far away in Singapore).

Now as you know, I'm primarily an objectivist when it comes to hardware so I guess it might surprise some that I also will check out the audiophile haunts over the years (like here and here) without getting too disgusted by the usual myths and pseudoscience promulgated. For me, it is a hobby that's fun and merges my love of music (the "spirituality" of the experience and where the subjective enjoyment resides), and the desire to understand how the world and technology truly works (where the objective side lives). The two IMO must exist in harmony, each finding balance in fulfilling the emotional side of being, yet not lost in the realities of this world and what just is.

Sunday, 3 May 2015

MEASUREMENTS: Corning USB 3 Optical Cable, Ground Loops, and Noise.

Folks, remember, the "Linear Phase vs. Minimum Phase Digital Filter Test" is still running as I post this! Please give it a try and report back in the survey. I want data and hopefully an opportunity to report back on what the readership perceives (or not perceive).

I. Introduction

Indeed, "noise" can be an issue with audio systems. There's little worse that can happen to an audiophile after spending hundreds or even thousands of dollars on new equipment, plugging everything in as per "best practice", getting ready to play your first piece of music, and finding that for some reason, noise has seeped through to disturb the expectation of pristine, clean background silence from which music can blossom...

Before proceeding further, remember that noise can sometimes be subtle, and very importantly, ambient noise must be low in your sound room. It's quite possible that slight hum and low-level noise may not be significant from a normal listening distance if the ambient noise level is high (something we urban dwellers especially do have to consider!).