Saturday, 15 January 2022

Using Victor's Oscillator as reference (1kHz, ultra-low distortion analogue sine generator). A quick peek at the APx555B Analogue & DAC Signal Generators @1kHz. And on playing music "for fun"!

Note the 2-pin power connector on the lower left.

As you've seen on the blog over the last year, I've been using the E1DA Cosmos ADC from Ivan Khlyupin for a number of measurements recently (early report discussed here). I remain quite impressed by the performance of this little device with some caveats (lower input impedance, individual unit idiosyncrasies including what "grade" device one has).

While the ADC comes pre-calibrated by E1DA and unless you really want to spend some time playing with it, one should probably just leave it alone. Nonetheless, it's pretty clear that this is the kind of device made by and for audio hardware geeks! ;-) One has the opportunity to use the Cosmos_Tweak Windows program to fine-tune the calibration by changing independent ADC 2nd and 3rd harmonic compensation amounts, SDM integrator setting, and digital filter for the ESS Tech ES9822 chip.

So then, for this post, let's spend some time in the area of calibration and see if we can tweak the ADC using the device above - Victor's Oscillator (US$57) - an ultra-low distortion, 1kHz analogue signal generator which comes pre-assembled and tested from Riga, Latvia. As you can see in the image, there are 2 single-ended RCA outputs, with volume control ranging from 300mVrms (-8.25dBu) to 2.7Vrms (+11.0dBu). Note that a 10kHz version (and other custom versions) can be purchased as well but for typical audio purposes, 1kHz is in line with human hearing sensitivity.

Tuesday, 4 January 2022

As We Hear It 2022: Hypex nCore NC252MP DIY, The Joys of Modern Digital Audio, Upsampled Streaming, and Audible Amplifier Differences.

Happy 2022 everyone and greetings from Honolulu. As Bing Crosby once sang, "Here we know that Christmas (and New Years) will be green and bright" in Hawaii. A welcome first escape from Canada since the Pandemic began for myself and the family. Always good to escape winter in Canada for a little bit even if it's from relatively mild Vancouver although this year looks like we also avoided the snowy cold snap!

As a first post for 2022, let's look in the (virtual) mailbag a select a few items from readers for an "As We Hear It" post that have come in over the last number of months.

Saturday, 25 December 2021

Audiophile Psychology: Reconsidering Zelinger's "Hi-Fi Fetishism" (HFN&RR, October 1981), and Lofft's "Sense and Nonsense" (SR, October 1982). On neuroses & fantasies.

Greetings everyone. Grab yourself a nice beverage, settle into a comfy chair, let us delve a bit into audiophile psychology.

I think this is an important topic; one that is implied in many of my posts over the years (in fact, we started 2021 with some related thoughts). Some of these psychological constructs I believe explain to a degree the ceaseless arguments we often see online especially when things go off track and disagreements appear irreconcilable between different "sides", "camps", "tribes"...

I. Hardware Audiophiles and Hi-Fi Fetishism

Let's discuss some ideas by building on writings from the past. To start, here's something interesting by J. Zelinger "Hi-Fi Fetishism: a psychologist's view of the lunatic fringe" from October 1981, published in Hi-Fi News & Record Review (I noticed that the link above can be marginal and might not work, here's a PDF of the text).

First of all, I must send kudos to Mr. Zelinger for a thought-provoking piece from the early '80s. It appears that many in the audiophile hobby diverged off into the direction of pure subjectivity, areas untethered from reality testing during that decade. He touches not just on the importance of psychoacoustics (as playing its role in perceptual adjudication of course), but into the touchy subject of the personalities of certain audiophiles.

Let's dive into this without fear and talk/think about this important topic and how it relates to us as "audiophiles" in the 21st Century.

Saturday, 18 December 2021

Upsampling: Native DAC Playback, and SoX PCM/DSD upsampling of 1kHz signal. (And the "Beatles: Get Back" documentary, "As the artist intended"?)

Notice one of the waveforms NOS.

A few weeks ago on this blog in a comment discussion, Bennet / Dtmer Hk talked about showing what it looks like when upsampling a 1kHz 16/44.1 signal in PCM side-by-side with DSD upsampling.

Sure, no problem! We can have a quick peek at the 1kHz sine tone from a couple of DACs for comparisons between direct playback with built-in filtering, upsampled in high quality with PCM SoX, and then using high quality DSD conversion with SoX-DSD.

Plus, let's also have a look at the recent Beatles: Get Back documentary series and some thoughts which I think relate not just to the "music lover" which I hope is in all of us, but also to the "hardware audiophile" side of this hobby.

Saturday, 11 December 2021

As We Hear It: Another High Dynamic Range Christmas Playlist (2021 Edition) by Allan Folz

Another High Dynamic Range Christmas Playlist (2021)

[Guest Post by Allan Folz]

Last year I shared with readers some of the Christmas albums that were a large part of our family's holiday tradition. Mostly they were CD's I bought in the mid and late 90's, which we listened to every year from Thanksgiving to Christmas. They were an eclectic mix of standards with the one thing in common that they all sounded great. Years later I learned about the importance of dynamic range and realized there was a objective reason I never tired of listening to these every Christmas, year after year. They sounded great because they had excellent dynamic range.

While those albums will always have a special place in our Christmas tradition, with streaming services now broadly available, over the last few years I have added some new favorites to our listening rotation.

Last year's guest post was so well received I took it as an invitation to write another post sharing some of our newer favorites. (Ed: Absolutely, Allan!) Many of these albums I listen to via streaming service so I don't always have dynamic range measurements from the CD's to compare. Rest assured they all sound great.

Saturday, 4 December 2021

RETRO: Technics SL-P110 (1986) & Sony CDP-690 (1990) CD Players. Did early CD players sound bad?

As we enter the last month of 2021, let's go back in time and consider the question: "Did early CD players sound any good?"

Over the years, I have heard this question asked many times. Typically among audiophiles, the answer almost invariably seems to be that early CD players from the 1980's "suck" (or similar negative expression). Generally, these comments appear without further details to explain the sentiment; as usual in audiophilia, we can find many opinions out there, but few bother with facts to build their case. I haven't seen many contemporary articles or writers discuss this question while looking at objective data to examine performance compared with the hi-res DACs we have these days.

The genesis of this article came about while chatting with my friend linnrd a number of months ago about the sound of DACs, modern devices, and what we grew up with back in the day. Lo and behold, he dug out the two machines you see above from his "archive" of older hardware. They appear to be in excellent condition despite being >30 years old!

Let's have a good look at the performance of these machines, and a listen as well, of course. ;-)

Saturday, 27 November 2021

MEASUREMENTS: S.M.S.L. A6 as amplifier [ICEpower 50ASX2(SE) Class D module]. (And DAC output - AKM AK4452 AMPT.)

Over the years, there have been devices I've been meaning to measure but one thing or another got in the way. This SMSL A6 amplifier was something I discussed here on the blog back in 2017 (a subjective review and measurements of DAC output). Over the years, this device has been happily amplifying signals for my dad's Klipsch Forté which is quite a sensitive speaker of 96dB SPL/m/2.83V; certainly by now it is very much "burned in". ;-)

I wanted to measure this device as an amplifier out of interest, knowing that inside this is the Bang & Olufsen ICEpower 50ASX2(SE) Class D module. While the datasheet for this amplifier module is already very detailed, there's nothing like measuring oneself!

This ICEpower module is rated at 2x47W into 4Ω, both channels driven to 1% THD+N. The power rating halves to 25W/channel into 8Ω. Within the ICEpower ASX series, there is also the 250ASX2 that will supply up to 250W/channel into 4Ω, and 125W/channel to 8Ω if you need more power.

The nice thing about this Class D module is that it's inexpensive and easily available for hobbyists such as through PartsExpress (current price US$118), sometimes through Amazon as well. You could buy one of these and get a simple case such as this Ghent Audio one and assemble it for yourself quickly.

Saturday, 20 November 2021

MEASUREMENTS: Yamaha RX-V781 A/V Receiver. Questionable magazine reviews of "high end" amps (D'Agostino). And thoughts on "hardware audiophiles", age and aging.

For this post, I want to have a look at the performance of my Yamaha RX-V781 as an amplifier. It's not new - I purchased this back in late 2016 to replace my Onkyo TX-NR1009 which I published on previously. Awhile back, I also looked at the pre-outs to examine the quality of this device's DAC.

This was an inexpensive receiver when I got it (as I recall, significantly less then US$700), being part of the "V" (Value) series from Yamaha, a step down from their "A" (Aventage) line. From the outside there's not much to look at, it's a black receiver with the usual buttons, knobs, and LCD screen to tell you the status. There's no swivel-open door to hide buttons like in more expensive models. It's a combination of plastic and metal exterior. Weight is not too heavy at 23lbs, mostly from the power transformer (looks like conventional E-I type, less expensive than toroidal but can provide greater capacity for size with potentially higher magnetic interference however).

The V781 is quite a feature-filled 7-channel amplifier capable of running 5.2.2 Atmos / dts-X, even compared to many of today's devices (see Yamaha specs here). What drew me to this model when I bought it was the fact that it had a full array of pre-outs so I could bring my own amps to the party if I wished.

Interestingly, even though over the years Yamaha updated these receivers with models like the RX-V385 and RX-V685, they never updated the "V78X" product line. My guess it that maybe the higher-end Value series might have been too close to the lower-end Aventages in terms of features and quality. For example the current Yamaha RX-A2A (~US$900) doesn't have a full complement of pre-outs, has more HDMI ins, no second HDMI out and quite similar to the Yamaha RX-V6A (US$650) already.

Wednesday, 17 November 2021

As We Hear It 2021 (I): Maurizio C on MQA, some ideas about TIDAL, and a few words about audio journalistic legacy...

Generation 1 earphones! For distant aircraft detection apparently...

As you might recall, over the years I have incorporated contribution posts from readers here on the blog. The article that follows was something I wrote back in the summer (2021) but since I was sick and tired of more MQA talk, I held on to it from publication a few months ago. Well, I think the time has come now that a few of the thoughts I wrote about TIDAL have actually come to pass - TIDAL just announced today that the price is down to $10/month, with the lossless 16/44.1 tier, pushing MQA into the "HiFi+" tier for $20/month. We're not sure if the lossless 16/44.1 tier has dumped the worthless MQA-encoded "MQA-CD" content though.

Here's the article with some modifications in light of the recent news...

A comment about MQA leading into 2021; some thoughts about the future of TIDAL and on journalistic legacy...

Here's an E-mail I received in late 2020 from Italy.
December 27, 2020 
To: Schiit Audio, Linn Audio
CC: Archimago

Dear Alls,
I'm an Italian, 60 years old, music lover and Older Analog Hi-Fi Fan and only recently I have converted to digital music, listening almost exclusively through the streaming services (Spotify, Tidal, QoBuz, Amazon, etc.).

Among hi-res listeners, Tidal is the most famous and expanding but they are "Forcing" the exclusive use of MQA format, with large investments, marketing campaigns, reviews from important audiophile magazines etc ..
Unfortunately this Campaign is gaining the upper hand, so much so that MQA Logo is now coveted by both manufacturers and sellers...

Saturday, 13 November 2021

Epson Photo ET-8550 13" EcoTank Printer: Excellent, economical, wider photo printing! A quick look...

While for the most part this blog concerns itself with audio stuff, every once awhile it's nice to diversify into discussions of other tech products; over the years we've talked about TV tech, CPUs, and networking for example.

Whether in audio or computer tech, I like products that represent value. This probably will become more important in the years ahead due to inflationary pressures with possible slowing of technological innovations in consumer electronics.

A few years ago, I mentioned about the Epson ET-2550 (these days supplanted by the Epson ET-2760) for basic color printing. Of all the years of using printers, that device was the first time I felt ink jet represented good value. Since 2017, that printer is still going strong! Never had any issues with print head clogging, and it has achieved stable connection through the WiFi in my home and accessible to all computers within the network sitting unobtrusively in the basement.

In fact, I was so impressed that I simply had to jump at grabbing one of these new Epson EcoTank Photo ET-8550 units when they became available recently. This is the wider format 13" (ie. A3+ paper) model. If all you need is standard-width 8.5" then you can check out the less expensive EcoTank ET-8500. As the name implies, this is intended for photo printing with its 6 ink tanks as opposed to the 4 on the ET-2550/ET-2760.

Saturday, 6 November 2021

RTL Utility: A look at audio interface latency. Discussion: PLACEBO / NOCEBO in audio (Darko + Lavorgna... again).

Hey guys and gals. For this blog post, I thought it would be of particular interest to some to have a look at latency and audio interfaces. As you can see in the picture above, I pulled out my Focusrite Forte for this alongside the RME ADI-2 Pro FS.

Latency is simply the delay for something to happen after an instruction has been issued for that event. Computers, device drivers, the hardware are not instructed "real-time" down to a bit by bit timeframe, but rather act on "chunks" of data generally issued with some buffer to keep the pipeline flowing. The buffering mechanism is a major, but not the whole, factor in the latency effect.

There is a balance to be struck though. The larger the buffer, potentially the more latency, but the less likely we could run into issues with dropouts. The shorter the buffer, the lower the potential latency, but the more demand on the CPU to deal with making sure the buffer doesn't go empty, and likelihood that we could have audio errors if needs are not met on time. This idea of "strain" on the CPU is particularly relevant on digital audio workstations (DAWs) when all kinds of DSP like VST plugins are used in audio production.

For us audiophiles, we generally don't care too much about latency because normally we're just interested in the sound quality once we "press play" and so long as the audio starts reasonably quickly and is not disrupted during playback, then there's nothing to complain about. Latency by itself has no effect on sound quality (despite the claims of some, which we'll address later).

Saturday, 30 October 2021

Revisiting the TEAC UD-501 DAC (2013): THD(+N), DSD output, Sweeps, Jitter, 1/10 Decade Multitone 32. (And on SSD transition, Corsair MX500 SSD, and Hi-Fi+ closes comments...)

After Bennet/Dtmer Hk's comment on this previous post, I thought it might be interesting to revisit my longtime friend, the TEAC UD-501 DAC that I bought new when it came out in 2013. My preview and measurements (Part 2 PCM, Part 3 DSD) are still online of course.

I still remember doing those measurements in my previous home - it feels so long ago! ;-)

These days with the E1DA Cosmos ADC and RME ADI-2 Pro FS available for measurements, let's take a trip down memory lane at what has been over the years a reference DAC for me. I think the TEAC UD-501 is a special device that ushered in for many audiophiles a cost-effective, high resolution, well-built, reliable, low jitter, asynchronous USB audio interface which I suspect has influenced the design and performance of other DACs over the years.

Spec-wise, it was one of the first to catch my interest with the ability to handle PCM 384kHz and DSD128. The high quality metal case looks serious. It's based on a dual-mono TI/Burr-Brown PCM1795 configuration with dual toroidal linear power supplies. There are a number of PCM and DSD filters including the ability to turn off the 8x oversampling and allow "NOS" (Non-OverSampling) mode. The quad JRC MUSES8920 opamps they used were also another "feature" talking point back then. (Quite a complete specs page here for the TEAC.)

Saturday, 23 October 2021

Miscellany: FlexASIO for 384kHz, Philips 2001 SACD/DSD64 test signals (thanks Black Elk!), and Roon network multicast. [And Coltrane's A Love Supreme Live Hi-Res, Music Industry Crystal Ball, Magic Quantum Fuses!]

A scene from The Simpsons 1996...

Hey everyone, for this week, let's talk about a few "miscellaneous" topics which I've either wanted to mention over the last few months or have just come up as interesting tidbits I think worth documenting but not necessarily large enough as topics in individual posts. The main topics are:

A. Instead of ASIO4All, we can use FlexASIO with the E1DA Cosmos ADC for 384kHz samplerate measurements in Room EQ Wizard.

B. A look at some "standard" SACD test signals from Philips back in 2001. With many thanks and great discussions with Black Elk.

C. Roon needs network multicasting. Check this out if you're running into network issues; I had some problems initially with my ASUS ROG GT-AX11000 and relatively complex home network.

Saturday, 16 October 2021

REVIEW: Topping D90SE DAC - Part III: Subjective Impressions, AMPT, and Summary. A few words about "warmth" and "accuracy" in sound systems.

This is the final part of my trilogy review/evaluation of the Topping D90SE DAC (see Part I, and Part II for the objective testing results).

As we end off, let's close with a discussion of subjective impressions developed over many evenings of listening (about a month or so). I've described the soundroom previously in some detail and for the two channel system, the main amplifier is my home-assembled Hypex nCore NC252MP, main front speakers are the Paradigm Reference Signature S8 v3, and dual subs (main Paradigm SUB1 with the little Polk PSW111). The Topping D90SE feeds my Emotiva XSP-1 preamp. All cabling is balanced XLR from DAC to amplifier (no need to fret, inexpensive Monoprice Stage Right XLR runs are all ya need, feel free to spend more on cables if you see fit of course).

I listened both with and without DSP room correction activated; generally I prefer with DSP. Knowing the frequency response characteristics (flat to 20kHz) and setting to "Fast Roll-off Linear" (Filter 5) allows me to use the same DSP settings for my room interchangeably with the RME ADI-2 Pro FS Black Edition without need to remeasure (equivalent frequency and time-domain performance). As discussed before, one of the benefits of a high quality DAC is that we can have even more headrooom with DSP processing whether it be full room correction or applying volume normalization like ReplayGain.

Saturday, 9 October 2021

MEASUREMENTS / REVIEW: Topping D90SE DAC - Part II: Resolution

In this Part II of the review of the Topping D90SE DAC, let's focus on the performance that this DAC can achieve. As you can see in the picture above, I've got the machine on the test bench ready to capture some data. Given the anticipated performance as described in Part I last time, the E1DA Cosmos ADC is used for the measurements being presented today.

As you can see on the LCD screen, it's playing DSD512 (22.6MHz) material at the time of this picture. For a more complete examination of the device's performance, let's see if we can capture both PCM and DSD performance.

This device does have a broad number of features, so let's try to hit the key (and also some not-so-key) features to better understand how well it works and if there are nuances that the audiophile should be aware of. As readers here I'm sure are aware of over the years, objective testing can often show anomalies that listening tests easily miss due to the limitations of human hearing and cognitive ability. Sure, one could argue that inaudible limitations are not important. I'd like to think that in principle, audiophiles have an interest in achieving both technical perfection as well as immaculate subjective performance.