Thursday, 25 June 2015

Digital Filters Test CLOSED & What Do We Have Here? [Updated]

June 25th has arrived!

As planned, this is the close-off date of the Linear vs. Minimum Phase Digital Filters Test. I hope everyone who wanted to participate got a change to have a good listen and submit their results! Thank you to everyone who did this. As usual, I'm very appreciative of the time and effort to download, load up the files, and of course the careful listening!

So, I will take the next little while to process the numbers and see what I come up with. I can share with you though that in total, I received 45 responses. This is actually close to what I imagined (about 50) based on past experience. The procedure isn't as simple as something like the 24-bit or MP3 tests done in previous years so I certainly did not expect the same kind of response.


Looks like North Americans "win" in terms of number of entries by geography :-). 62% (28) of the respondents were from North America, followed by 29% Europeans, then Asians and Australians the same (4.4% each).

Okay... I will post up the data / analysis / and conclusions when I get the information processed!

Now, on a side note... What do we have here?

Sunday, 14 June 2015

MEASUREMENTS: Speaker Cables / Wires (Canare, Kimber, and the "Frankenstein" Zip Cord)


Awhile back - in October 2014 to be exact, I spoke a bit about speaker cables, posted some electrical data, and made myself a pair of 4' Canare 4S11 bi-wireable lengths with locking banana plugs to use at home. These are the black cables you see above to the right. I've been happy with them since and as I noted in that previous post, I heard no discernible difference compared to standard 12G copper zip cord nor did I feel bi-wiring made a difference so I reinserted the speaker jumpers to effectively make this a single 11G cable (no risk losing the jumpers!).

However, I presented no measurements at that time. As I mentioned last week, since I've been doing some room measurements lately (which I will talk more about in a future post), I figured it was time to put my impressions to the test and see if I can detect a difference objectively with speaker wires. Today, I present a few measurements in 2 parts - Part I is with a very "poor" zip cord (the above image, left cable), and Part II with a well known and "audiophile approved" commercial cable.

Tuesday, 9 June 2015

MUSINGS: On Music Streaming, now that Apple's in the game...



So, the big news this week is Apple and the streaming audio announcement; Apple Music. Of course music streaming services have been around for years: Spotify, Pandora, Rhapsody, Google Play Music, XBOX Music, Rdio, KKBOX (Asia), etc... Take your pick. Oh, let's not forget the mother of all media streaming - YouTube! Then there's also the FLAC lossless audiophile "darling", Tidal.

As usual with Apple announcements, it seem like the word "revolutionary" gets used rather liberally (along with describing objects as having "magical" properties). According to Apple, this announcement is "revolutionary", just like MQA from Meridian is "revolutionary" I guess. Lots of revolutions going on these days :-).

Supposedly this new Apple Music service will be streaming 256kbps AAC (not verified by Apple yet) and as expected from the fringe, some folks still are up in arms over the use of lossy compression with streaming services. It's as if lossy compression is morally evil and the mere mention automatically taints the product as deserving to be treated with disdain. Well, I guess I just don't see/hear it that way (the times I actually stream music off the Internet).

Sunday, 7 June 2015

MEASUREMENTS: The Effect of Speaker Grills...

"Clothed" or "Naked"... What's the difference?

A quick measurement for this week...

I was curious the other day as I was doing some room measurements what effect speaker grills make. My Paradigm Signature S8 V3's have typical fabric and plastic grills up front. Simple question - How much difference does the grill make to the sound of the speaker?

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!).

Sunday, 26 April 2015

INTERNET BLIND TEST: Linear vs. Minimum Phase Upsampling Filters


I. Introduction

Ladies and gentlemen, audiophiles of all ages; you have probably seen pictures like the ones above many times in the magazines, posted online, etc. You know that many DACs these days feature the ability to adjust the way the antialiasing reconstruction filters are "tuned". I remember reading about and becoming fascinated by the different filters back in 2006 with Keith Howard's article on Stereophile. But it wasn't until around 2009 that I noticed Meridian started using minimum phase settings in their equipment like the 808.2 Signature Reference CD player. (I don't know if many other consumer audio devices used a form of the minimum phase filter before 2009; perhaps not as well advertised as Meridian?)

Monday, 20 April 2015

PERSPECTIVE: Poll - Upgraded USB and Sound?

I enjoy visiting the Steve Hoffman Forums for perspective. I think it's probably one of the most balanced places to hang out at. Of course, as in any audio forum, there will be a number of heated arguments here and there, but overall, it's great to see a place where heterogeneous music lovers of various experience levels and beliefs can congregate, share tips, and get advice... It's certainly one of the more vibrant audio communities out there!

Recently there was an interesting poll on whether USB cable upgrades can improve a system's sound quality. Titled "The Great USB cable debate poll" (full disclosure, I took part and posted a comment as well), it ran from February 22 to March 8th before it was closed. In total, it received 415 votes, gathered 36 pages of responses and the outcome was:

About 1/4 felt that upgraded USB cables make a difference, and 3/4 did not. Surprised?

Saturday, 11 April 2015

ANALYSIS: DSD-to-PCM 2015 - foobar SACD Plug-In, AuI ConverteR, noise & impulse response...

Noise characteristics of PCM vs. DSD - image found here.
In my post last week looking at the various DSD-to-PCM converters, Solderdude Frans made a good suggestion... Let's have a look at the newer SACD plugin which has superseded the DSDIFF plug-in as the converter of choice these days for foobar. Also, it was suggested by Yuri Korzunov, the author of AuI ConverteR 48x44 to have a look at his converter package as well.