Audio Issues when Using Apple’s USB-C Digital AV Multiport Adapter

MJ1K2I record podcasts and screencasts, and usually do my audio recording on my iMac, but recently I’ve been using my MacBook Pro (2017, sans touch bar) a bit. Since it only has two ports, and I needed to record something with my iPhone connected to it, I attached the dongle you see on the left: it has three ports, one is USB-C, one USB-A, and one HDMI. I bought this a few years ago to use with the crippled single-port MacBook, and while I don’t use it often, now that I have 100% more ports on my MacBook Pro, there are times I need it. The battery was running low, and I needed to connect a microphone via USB, so I used one port for the iPhone, and the other for the power and microphone.

I recorded about two minutes of audio for a screencast using Audio Hijack, and, as I always do, opened it in Rogue Amoeba’s Fission to check it and edit it. This is what I saw:

Audio artifacts

As you can see, there are some very nasty audio artifacts on the recording. Interesting, they only show on one channel, but they are very loud diginoise. I don’t know why this happens, but when I plugged the microphone directly into a USB-C > USB-A adapter, then into the MacBook Pro, the problem went away. Also, when the power cable wasn’t connected to the mammoth dongle, it worked fine. I can only assume that there’s something wrong with the larger dongle when it’s sending both power and data. I don’t think there’s any way to fix this, and I don’t really need to use this configuration often, but it’s worth noting if you do plan to do audio recording and need another peripheral connected to a Mac via one of these dongles.

Fortunately, I didn’t discover this after recording a podcast…

Apple to launch branded over-ear headphones as soon as this year – AppleInsider

“In a note to investors seen by AppleInsider, Kuo predicts Apple to debut a branded high-end, over-ear headphone with an ‘all new’ design to add to its growing audio accessory lineup. A specific launch timeline was not provided, but Kuo believes the device is unlikely to debut prior to the fourth quarter of 2018.

Though not specified in the note, the headphones will likely feature wireless connectivity. Kuo says Apple is aiming to deliver a product that boasts the convenience of AirPods but with better acoustic qualities.”

It’s not surprising that Apple is planning to do more in personal audio; it’s the perfect complement to its Apple Music service. The HomePod, while interesting, suffers from a Cupertino-imposed sound signature that is not flattering to all music, similar to the Beats headphones. If Apple were to make their own branded headphones, I would expect them to introduce some interesting audio technology, notably providing headphones with a built-in DAC that only work over the lightning connector. The company has lots of opportunities to play with advanced sound technologies, though in headphones there are more limitations than in a speaker.

I wouldn’t expect Apple to get rid of the Beats brand any time soon; I’d think that an Apple headphone will be premium priced, more as a showcase of what the company can do than as a mass consumer device. For now. I expect Apple to do a lot more with audio in the future.

Source: Apple to launch branded over-ear headphones as soon as this year

Computer Audiophile Reviews the HomePod

Chris Connaker, who runs the Computer Audiophile website, and who is a regular guest on The Next Track podcast, was initially not interested in the HomePod. It’s not the type of device he would use, he said, but given the amount of coverage it was getting, he decided to buy one and try it out. Here’s his review.

One could raise one’s eyebrows a bit when Chris mentions the reference system he uses to compare his music with the HomePod:

Speakers: TAD Compact reference One CR1 $45,000 (frequency response 40Hz–20kHz, ±3dB)
Amplifiers: Constellation Audio Inspiration Monoblocks $20,000 /pr
DAC: dCS Rossini $24,000
Cabling by Wire World and 512 Engineering ~$10,000

But he also uses:

Klipsch: The Three $499 (frequency response 45Hz–20kHz, ±3dB)

To be fair, you can’t compare the HomePod just to other, similar speakers. You need to compare it to the way music should sound. What you are trying to determine is how much is lost or gained by using that speaker when comparing it to a “real” stereo. In my testing and review, I compared it to my office sound system, which is a Yamaha receiver (£600) and Focal Chorus speakers (£200), with some cables (£6) and banana plugs (£8). So while my system was a bit less expensive than Chris’s, it’s still a pretty good system.

Here’s what he thought about the first piece of music he listened to:

The HomePod shouldn’t come close to my reference system, and it doesn’t. Let’s not kid ourselves. Apple has more money than some countries and has hired very smart engineers, but it can’t change the laws of physics. Starting with the impressive aspects of the HomePod playing Red or Dead, Randi’s vocal is crisp and clear, but has a very slight soft edge. The very fine details for which audiophiles frequently listen aren’t nearly as audible through the HomePod as they are through a true HiFi system. The HomePod has a very nice sound that will likely please most listeners without causing fatigue on tracks like Red or Dead. If I was unaware of the true sound of this track, I’d think the HomePod had done a pretty good job reproducing the vocal portion.

As he says, “If I was unaware of the true sound of this track…” That’s important; for many people, the HomePod may be the best speaker they’ve ever owned, because they simply never owned any good hi-fi equipment. They may find the sound attractive, or flattering, and, if so, that’s fine. But it’s important to put this into perspective: how it sounds compared to the music “the way the artist intended,” as audio buffs like to say.

Chris immediately highlights the main problem with the HomePod:

The HomePod is a bass monster, for better or worse. […] Thumps and booms are pretty much what the HomePod is all about and it’s very clear after a single listen to a track with very controlled bass.

Everyone who cares about how music sounds is saying this; it’s not just subjective. People who are used to the high bass of Beats headphones may think this is normal, but as I pointed out in my first impressions of the HomePod, some music sounds great, and some music sounds pretty bad, because of the excess bass.

For another song, he highlights one of the other issues I noticed:

the HomePod was nowhere near any of the HiFi system on which I’ve heard this song. Closed-in with a jumbled mess of sounds and a haze over the top is how I’d describe this track through the HomePod.

That “jumbled mess” is how a lot of more complex music sounds. Coldplay sounds great, but a string quartet I listened to sounded horrible. A jazz piano trio had no depth, no detail, and many tracks just sounded confused.

I love Metallica’s …And Justice for All album for both the music and the way it sounds. It’s not a favorite of many Metallica fans, but I just love the sounds of Lars’ Tama drum set. The track One features a nice soft-fish guitar intro. On the HomePod this guitar sounds really good and has good tone. I can see many music lovers really enjoying sounds like this. In fact, I wish the entire track sounded as good as this opening sounded through the Pod. I’m frustrated to say, the HomePod just falls apart at the 0:55 mark in the song. The drum sound that I love, that I’ve played for so many people on so many different systems including one a couple weeks ago in New York City, was totally wrong. It sounded like a huge band of upper bass frequencies was missing. I heard Lars’ kick drum, but not all of it. It’s as if there was a filter on the upper end of the drum set and an exaggeration on the very bottom end.

Exactly. A more restrained song I listened to, Brad Mehldau’s cover of the Radiohead song Exit Music (For a Film), showed how drums don’t do well on the HomePod:

“Moving to jazz, I tried out one of my standard test tracks, Brad Mehldau’s Exit Music (For a Film), a cover of the Radiohead song, on The Art of the Trio, Vol. 3: Songs. I love this track because of the subtle way it builds up, and because of the light touch of drummer Jorge Rossy, as he taps the cymbals, creating interesting polyrhythms with the piano. Unfortunately, the cymbals are too quiet, and the bass gets muddied with the piano, turning an intricate song into a flat-sounding piece for piano trio. This was also the case with other Brad Mehldau recordings.”

But, okay, that’s comparing the HomePod to Chris’s $100K system. How about his $500 Klipsch Three speaker?

It has a much more balanced sound than the HomePod. Eddie Vedder’s Society was very enjoyable through The Three as opposed to the HomePod. I A/B’d them for twenty minutes to make sure I heard what I thought I heard. I honestly expected the HomePod to put the Klipsch unit to shame, but that wasn’t the case.

Chris briefly mentions the Siri integration, but given that Siri is only half-baked on that device, even that isn’t a compelling reason to buy it.

His conclusion:

Perhaps some normalcy has now been added to the hysteria. I agree with Consumer Reports. I really wanted to like the HomePod and I wanted [it] to sound fantastic. The truth is, the HomePod is good and I’d recommend it to people who have to have Apple products. If people want a voice assistant, get a voice assistant. If people want a loudspeaker, get a loudspeaker. Splitting the duties provides much more flexibility to purchase the best of both worlds. Google and Amazon offer far better products for voice. With respect to sound quality, there are many other products I’d recommend over the HomePod, starting with The Three from Klipsch.

There are lots of great standalone speakers. The lack in functionality as “smart” devices, but it’s really not clear how many people want these devices. If you’re all in on the Apple ecosystem, it’s a good option, but if you really care about audio quality, it’s far from the best you can get for the money.

HomePod Audiophile Review: Sound Performance ‘Deserves a Standing Ovation’ – Mac Rumors

Update: The author of the review has now added an initial paragraph to his very long text, pointing out that, well, maybe, just perhaps, his measurements aren’t worth much.

EDIT: before you read any further, please read /u/edechamps excellent reply to this post and then read this excellent discussion between him and /u/Ilkless about measuring, conventions, some of the mistakes I’ve made, and how the data should be interpreted. His conclusion, if I’m reading it right, is that these measurements are largely inconclusive, since the measurements were not done in an anechoic chamber. Since I dont have one of those handy, these measurements should be taken with a brick of salt. I still hope that some of the information in here, the discussion, the guesses, and more are useful to everyone. This really is a new type of speaker (again see the discussion) and evaluating it accurately is bloody difficult.

He still doesn’t address the question of DSP affecting the sound differently when music is playing rather than a sine wave. But I think it’s clear that this whole thing is, well, a waste of time.

I wonder if Phil Schiller is going to tweet about this addendum…

HomePod reviews from the tech press came thick and fast last week, and while the smart speaker’s sound quality was consistently praised, most reviews were based on subjective assessments and didn’t take into account professional-grade output measurements. Early on Monday, however, Reddit user WinterCharm posted exhaustive audio performance testing results for HomePod to the Reddit audiophile community.

Using specialized equipment and a controlled testing environment, the review features in-depth analysis of the smart speaker’s output when compared to a pair of KEF X300A digital hi-fi monitors, representing a “meticulously set up audiophile grade speaker versus a tiny little HomePod that claims to do room correction on its own”.

I’ve been following this Reddit thread and its published results. It’s amazing that in a world of audiophiles who obsess over which USB cable makes their music sound better, that this person performed all of these measurements, and forgot to mention that the HomePod uses digital signal processing to alter all music that it plays. In other words, it is far from neutral, and audiophiles make a big deal about their equipment being neutral. The frequency response may be excellent, but the equalization alters the music from what it should sound like.

In fact, I think it’s highly possible that this reviewer has based the conclusions of his testing on false assumptions. The HomePod has dynamic digital signal processing; it alters the music based on the music. In other words, it’s not a fixed EQ setting, but one that changes as music is played (and according to the room where it’s played). As such, sending single frequency sine waves, or whatever he did, won’t show the results of the EQ.

You can easily hear this by playing some music you know well first on a stereo, then on the HomePod. For some music, the EQ is gentle; for other tracks, it’s aggressive, very bass-heavy. My speculation is that there’s some sort of algorithm that allows certain types of music – with, say, a close balance between bass and treble – to not have such a drastic effect on the bass, and others – more bass-heavy music to start with – to be more greatly affected.

In other words, this person measured the trees, but not the forests.

Source: HomePod Audiophile Review: Sound Performance ‘Deserves a Standing Ovation’ – Mac Rumors

The case against subwoofers for music – CNET

Subwoofers for music systems don’t make sense to me anymore. For home theater, where movies rely on low-frequency effects subs to make the magic happen, subs are essential. No argument here, but music rarely has extremely deep, under-50Hz bass, and most speakers with 5-inch (127mm) or larger woofers can muster 50Hz bass in small or midsize rooms. Of course, if you crave gut-shaking bass or you have a big room, larger speakers and subs are recommended.

I started mulling this over after I read Damon Krukowski’s Pitchfork op-ed, Drop The Bass: A Case Against Subwoofers, and he had me tripping down memory lane to when I used subs in my home system. Sure, subs add bass, that’s easy, but achieving a truly seamless subwoofer blend with the system’s speakers is challenging. Getting most of the way there takes a day or two fiddling with the sub’s controls and experimenting with room placement. Achieving the perfect blend isn’t always possible — subwoofer crossover tweaking isn’t an exact science.

Over time I found my sub’s presence intrusive in the sense that I was aware of what the sub was contributing to the sound, pulling me away from the music. When the sub is perfectly integrated with the speakers you shouldn’t hear the sub; all of the bass should appear to come from the speakers.

Exactly. Too many people turn the subwoofers up so they can hear them; and that makes music muddy.

About a year and a half ago, I mulled the idea of purchasing a sub-woofer for the audio system in my home office, where I do a lot of listening. (I already have one in the TV room, but only turn it on when I’m watching a movie where I think it will make a difference.) We recorded an episode of The Next Track podcast about sub-woofers: about how useful they are, and about how to set them up.

I was able to correctly configure the sub-woofer; it’s not as complicated as Steve Guttenberg says. And the new receiver I bought a few months ago – the Yamaha R-N803 ( – comes with a microphone to set up the speakers, the kind you get with an AV amplifier. So it automatically calibrates the sub-woofer’s volume to match that of the main speakers.

Gutterberg references an article by indie musician Damon Krukowski, who rails against sub-woofers, especially for live music, and finds lots of people, including musicians, to support his theory that they’re not worth the time, either live or at home. He thinks it’s a recent development in sound, that it started in the 1970s.

Between the wane of freak folk and the rise of EDM, it seems every rock club in the indie universe decided to install subwoofers–often directly under the stage, where they rumble back into acoustic instruments

To be fair, rock clubs may have only installed them recently, but discos were using them in the 1970s. It’s easy to argue that “for acoustic duos who don’t even use a bass,” like Krukowski’s music, it’s useless, but that’s a pretty specious argument. It’s the “it doesn’t happen to me so it doesn’t count” argument that is so common around anything in technology.

Live music for many instruments and ensembles does create frequencies that are below those of most speakers, at least home speakers. One reason the Grateful Dead built The Wall of Sound was to be able to reproduce the frequencies of their music with great fidelity. Phil Lesh’s bass was capable of going very low in Hertz, and the Wall of Sound reproduced these frequencies. But even an instrument like a cello can go down below the frequency of many home speakers; its lowest fundamental is 65 Hz, and that of a double bass is 42 Hz. So if you’re listening to music at home with those instruments, you’d lose out on some of the sound that you would hear live.

As long as your sub-woofer is correctly calibrated, it adds a ground to your music; not all music, but when you are listening to music that can benefit from it, a sub-woofer can make that music sound fuller, richer. Don’t turn it up just becaus you want more bass, but understand that, as Guttenberg said, you shouldn’t hear it.

Source: The case against subwoofers for music – CNET

HomePod Review: When it Sounds Good, It’s Great; But It Doesn’t Always Sound Good

It’s been a long wait, as Apple pushed back the release of the HomePod, originally announced for the end of last year. There has been a lot of speculation about what a $350 speaker would sound like, and early reviews have been generally positive, but mostly in comparison to other “smart” speakers, such as the Amazon Echo and the Google Home.

I took delivery of my HomePod this morning, and have spent several hours listening to it. As is my wont, I have played music I’m very familiar with in order to try it out. I strongly believe that using special test records to audition audio equipment is wrong; you need to play music that you know by heart, where you know when different instruments come in, how voices sound, and what sort of beat and rhythm it has.

The HomePod uses digital signal processing (DSP) on all the music it plays, whether it’s from Apple Music, iCloud Music Library, your iTunes library, or your iOS device. Unfortunately, you have no control over this DSP. It’s a one-size-fits-all algorithm, which, while it certainly treats different types of music differently, still tries to mold everything the same way. It’s almost as if the HomePod is the stationary equivalent of Beats headphones: decent sound, but too bassy; good for certain types of music, but not all.

Here are some thoughts after listening to a few dozen pieces of music.

Read more

The Next Track, Episode #88 – Buying and Selling Hi-Fi Equipment

The Next Track Blue Flat Button2 400pxBuying and selling hi-fi equipment can be fraught with problems. Chris Connaker joins us to talk about the situation, and to present his new venture, Superphonica, a platform for buying and selling audio goods.

Listen to The Next Track: Episode #88 – Buying and Selling Hi-Fi Equipment.

Find out more, and subscribe to the podcast, at The Next Track website. You can follow The Next Track on Twitter at @NextTrackCast, to keep up to date with new episodes, and new articles from the website.

Computer Audiophile Launches Superphonica

Chris Connaker, who runs the Computer Audiophile website, has just launched Superphonica, a hi-fi focused marketplace for selling new and used audio products, and more. As: he describes it:

Superhonica is a HiFi focused marketplace where private individuals, dealers, and manufacturers all sell new and used products to the world. This isn’t our grandfather’s classified section. We’ve leveraged new technology to offer people the best buying and selling experience in the industry. Superphonica is CA’s marketplace, but it isn’t only for what some would consider CA type products. Superphonica is for digital audio, analog audio, music, and even products like NAS drives. In fact, this is why the marketplace goes by the name Superphonica rather than Computer Audiophile. Why limit one’s buying and selling options because of a name or perceived product focus?

If you’re into hi-fi – audiophile or not – check out Superphonica. Chris has a lot of ideas on how to make the process of buying and selling better, more transparent, and fairer.

How Hi-Fi Magazines Write about Cables, Part 22: Getting Up and Dancing

Who wouldn’t want a turntable that makes them want to get up and dance? A reviewer at Cnet seems to have found one. He says:

I play music all the time at home, but I couldn’t help but notice that my wife was grooving and dancing more when I played tunes on the Pro-Ject Classic SB belt-drive turntable. She didn’t have to say it’s a great sounding turntable, her actions spoke louder than words.

Well, that’s impressive. I assume she never, ever wants to get up and dance when you play music on a different turntable. Because it’s not the music; not the mood; not the presence of, perhaps, mood-enhancing substances. It’s just the turntable.

I find it interesting how high-end audio reviewers – and listeners – ascribe life-changing audio quality to a single element in the chain, yet at the same time try to explain how every item in an audio chain has an effect on the sound. Let’s take the minimal system required to play back music from a turntable, and look at all the elements that audiophiles constantly say make their music sound so much better:

  • Power cable
  • Power conditioner (Optional)
  • Turntable
  • Cartridge
  • Stylus
  • Rack (to keep the turntable rock-solid, and somehow improve the soundstage)
  • Records
  • Interconnect cable to pre-amplifier
  • Pre-amplifier
  • Amplifier
  • Speaker cables
  • Speakers (or headphones)

This is a simple audio chain, purely analog, so there’s no DAC, USB cables, and no worries about getting a good sounding hard disk.

In any case, the reviewer here was convinced that it was the turntable that changed everything. It’s pretty magical too:

Oldsters remembering the bad old days of crappy turntables, and the new-to-vinyl convert who frets over LP’s surface noise, clicks and pops will find newfound quiet spinning LPs with the Classic SB. Of course it can’t totally eliminate those noises, but they recede into the background.

Somehow this turntable is muting noise on records; that alone would make it product of the year on any audio website.

But, as always, the reviewer waxes acidic when talking about the music he listens to:

Bob Marley’s “Natty Dread” LP almost completely disarmed my reviewer brain, I had to force myself to listen critically, but there wasn’t much to criticize, the sound was lively and Marley’s soulful vocals were beyond reproach. The band’s solid support threw a party for my ears.

And, as always, nothing he says above has anything to do with the sound of the turntable; it’s just the music that he’s describing. Or:

That led to Prince’s “Purple Rain” and the energy level surged a few notches. The Classic isn’t the sort of ‘table that sounds soft or mellow, Prince’s ‘classic album sounded fresh as the day it was minted.

Translation: “Argle bargle wargle.” There are journalists that really think writing something like this is journalism.


For some reason the Classic had me spinning my jazz LPs more than I usually do — there was just something about the way it brought out the band’s interplay, especially among the rhythm section.

Notwithstanding the fact that he doesn’t say who “the band” is, this is audiophile-grade BS.

The Next Track, Episode #81 – Ask Andy: Ohms and Decibels

The Next Track Blue Flat Button2 400pxWe bring back our regular guest Andy Doe to discuss some of the technical terms we read about with audio equipment: ? and dB, also known as ohms and decibels.

Listen to The Next Track: Episode #81 – Ask Andy: Ohms and Decibels.

Find out more, and subscribe to the podcast, at The Next Track website. You can follow The Next Track on Twitter at @NextTrackCast, to keep up to date with new episodes, and new articles from the website.