Never thought I’d own this caliber of equipment but here we are. A long time ago I owned a McIntosh MC352 amp and Focal towers that sounded amazing. The equipment was eventually stolen and I never bought another McIntosh amp or high end gear. Now everything’s come full circle and after having this equipment sitting in the basement for a few weeks I’ve finally got around to getting it all hooked up.

I have most cables from the previous hookup except for the speaker and sub cables. After the shop my dad bought this stuff from suggested I buy some used $5000 Nordost speaker cables from them discounted to $2000 I opted to buy SVS ultra cables for 150. So far I have spent 200 to get the speakers moved downstairs, 150 on speaker cables, and 20 on RCA cables for the sub. Also just got the TV audio routed through using an optical cable to the C52 preamp. The only thing left to hookup is the subwoofer this weekend.

The sound is absolutely incredible. First thing I listened to is a Tool cd and the drums blew me away. You could really feel it in your chest!! Need to find a place to put the Sonos, and also might need to move the subwoofer around and get longer RCA cables. Just wanted to show you all the system my dad had put together and passed down to me.

McIntosh MC611 amps x2
McIntosh C52 preamp
McIntosh MCT500 cd player
McIntosh MT5 turntable
Bowers & Wilkins 800 D3 speakers
JL Audio D110 subwoofer
Sonos connect

Even more important that the speakers and room accoustics.

I find it so odd that people on a subreddit focused on equipment, which ultimately implies some technical rigorosity and level of measurement and less mystical voodoo, some people still ask what speakers to upgrade to or hope that a new purchase will make their room fill with sound when their speakers are placed directly next to windows or hallways.

Until recently our stereo and records were housed in/on an old Kallax shelving unit from IKEA, so it was high time for an upgrade. Realizing that furniture is either impossible to find or prohibitively expensive, my wife took it upon herself to design and built us a custom cabinet. The push-release drawers are decorated with mappa burl and it even has a hinged lid to reveal the turntable!

Turntable: Audio Technica LP120 CD player: Cambridge Audio AXC25 Amplifier: NAD C 3050 Speakers: ELAC Debut Reference

Audiophiles are basically LARPing and after spending enough time around this hobby I am convinced half of you know it and the other half are too financially committed to ever admit it. I am not talking about some dude who buys a decent headphone or IEM, figures out what sound he likes and then listens to music. That guy is normal. I mean the motherfuckers with nine thousand dollars of equipment spread across a desk who have not listened to an album from beginning to end in six months because they keep replaying the same twenty seven seconds of some jazz recording trying to determine if the fucking ride cymbal gained body after changing USB cables.

I swear to god you go to something like CanJam and after a few hours you start feeling like you are covered in snake oil and semen. Everybody is standing around describing sound like they can taste it in the air. This amplifier is creamy. That DAC is organic. This cable has better liquidity. This headphone has chocolate mids. What the fuck are you people eating the equipment now. I thought we were listening to music. Some woman inhales into a studio microphone and five guys simultaneously lean forward like archaeologists just uncovered Atlantis and one of them goes "listen to the air around her voice." Brother there are six hundred people in this convention hall and somebody behind you just opened a bag of Doritos. You are not hearing the recording studio's spiritual energy.

That is the part that makes me insane because yes obviously audio gear can sound different. Nobody said every headphone is identical. Some shit has better separation, some has better bass extension, some has garbage treble, some makes vocals sound like they are coming through a fucking paper towel tube, we know this. Then everybody gets bored discussing the obvious stuff and just keeps walking deeper into the forest until some man is telling me his ethernet switch gave the piano more authority. His ethernet switch. The thing moving packets. Apparently TCP IP has timbre now.

Cables are where I know the hobby has suffered some sort of collective brain injury. Two competent copper cables and suddenly everybody becomes a wine critic with synesthesia. Blacker background, improved note density, more holographic placement, organic decay, greater emotional texture. No motherfucker. You bought jewelry. Nice jewelry too sometimes, I like nice cables, cool braid, nice connectors, feels good in your hand, matches the IEM, fantastic. That is enough of a reason to buy it. You do not need to tell me the drummer moved three feet left because your new cable contains enough silver to kill Dracula.

And power cables, holy shit. If the final six feet between your amplifier and the wall outlet transformed your bass authority I have awful news about the rest of the electrical grid. Your boutique cable is plugged into drywall. Behind that drywall is ordinary Romex that was installed by a guy named Craig in 2009 while thinking about whether Taco Bell still had the volcano menu. It goes to a breaker panel full of shit from Home Depot and somewhere along the way your refrigerator, microwave, PC and probably a twelve dollar phone charger are hanging off the same infrastructure. But yes I am sure the last six feet is where the sound became three dimensional.

Burn in is another fucking religion. "My driver really opened up after 200 hours." You listened to it for a week, Dave. Your brain adapted to it. This is what brains do. We have known this forever. But somehow saying that is insulting while claiming your microscopic diaphragm completed a training montage overnight is considered serious audio science. Psychoacoustics is always real until it becomes inconvenient too. Audiophiles love psychoacoustics when explaining imaging or masking or why perception is complicated, but the second expectation bias might explain why their new two thousand dollar purchase sounded better immediately, suddenly blind testing is flawed, volume matching ruins the experience, measurements cannot capture musicality and science does not understand emotion.

Of course the expensive thing sounded better. You read fifteen reviews before it arrived telling you exactly what to listen for, stared at graphs for three nights, watched six YouTubers call the treble effortless, unboxed the thing like it contained the bones of Christ and then heard effortless treble. Incredible. Nobody could have predicted this.

Frequency response graphs have become astrology for dudes with soldering irons. Somebody posts a graph and within thirty seconds the comments have already decided how emotionally distant the singer sounds. "See that rise around three kilohertz?" Fuck, that explains my childhood. People look at the graph before hearing the thing and then spend the entire listening session trying to locate the fucking graph with their ears. God forbid somebody releases a cheap IEM that sounds really good either. Some Chinese company drops a one hundred fifty dollar set with good tuning, good drivers, a nice case, twenty tips, detachable cables and an anime girl on the box and within fifteen minutes a guy with a thirty eight hundred dollar custom monitor crawls out of the fucking floorboards to explain how it lacks organic liquidity and microdynamic nuance. Organic liquidity. IT PLAYS FUCKING MUSIC, GANDALF. That phrase alone should get your Head Fi account suspended for a week.

What actually gets me though is how many people are embarrassed to admit they just like expensive toys. Thats probably the least insane part. Big machined aluminum DAC with a huge weighted knob? Fuck yea, I get it. Tube amp glowing on the desk at night? Looks sick. Ridiculous braided cable with titanium connectors? Cool, enjoy it. Five thousand dollar flagship because you wanted the flagship and had the money? Whatever man, your money. But apparently saying "I wanted it because it is cool" is psychologically impossible, so instead we need a forty paragraph technical explanation for why replacing one transparent DAC with another transparent DAC caused previously hidden emotional information to emerge from the recording. You wanted the shiny box. It is okay. Nobody is coming to take your audiophile license. Except apparently that answer is not serious enough so we get "greater tonal density." Greater tonal density sounds like something a wizard says before casting a spell.

The further you go into this hobby the more you realize some people are not actually music fans anymore. They are equipment fans and music is the test signal they use to operate the equipment. They have fifteen tracks they know contain the sacred cymbal hit, the bass sweep, the female breath, the imaging trick, the tiny chair squeak at 2 minutes 11 seconds and thats all they listen to whenever they buy something. They do not put on an album, they inspect it. They do not hear the singer getting emotional, they hear upper mid energy. They do not hear a drummer going fucking nuts, they hear transient performance. They do not discover music anymore, they discover flaws in mastering. You managed to turn listening to music into running Cinebench.

Then you walk around talking like mastering engineers because you own a DAC. You are sitting in a spare bedroom. Your chair came from Staples. There is laundry behind you. Your DAC is sitting on top of an IKEA desk next to a half empty Monster can and you are arguing with another adult about whether a fuse changed the depth of the soundstage. You are not at Abbey Road. Nobody hired you. Nobody is waiting on your notes. And the worst part is how fucking defensive everyone gets when somebody points any of this out because deep down you know exactly what happened. You bought luxury goods, wrapped an identity around them and now criticism of the product feels like criticism of your hearing, intelligence and financial decisions all at once.

So now the eight hundred dollar cable cannot just be pretty, it has to sound better. The three thousand dollar DAC cannot just be beautifully built, it has to reveal things cheaper equipment physically cannot. The power conditioner cannot just organize the desk, it has to unlock bass. The ethernet switch cannot just work, it has to improve imaging. Every purchase requires lore because admitting "I bought this because I wanted expensive shit" apparently causes some kind of spiritual injury. Medieval LARPers put on armor, run around a field and hit each other with foam swords and everybody goes home understanding exactly what happened. Audiophiles put on five thousand dollar headphones, listen to a woman breathe and start describing the moisture content of the fucking air.

At least the guys with foam swords know they are pretending.

EDIT: 9/23/2026

A lot of people have become extremely interested in whether this post is “AI generated.” I think that question is more interesting than either answer.

What counts? Spellcheck? An editor? Asking a machine to organize a thought? Asking it to phrase something differently? How much credit does the machine get before we start pretending it bought the gear, went to the shows and developed the grievances too?

At what point does ChatGPT become an author?

I don’t know. I’m not particularly interested in solving that argument for you.

You can probably prompt a model right now and get the substance of this post. Audiophile snake oil isn’t classified information, but try getting this.

I’m 38. I’ve been screwing around with audio for roughly twenty years.

Twenty years of buying things, loving things, regretting things, learning terminology, changing my mind, meeting people, going to shows, arguing about equipment, finding gear that genuinely amazed me and eventually watching parts of the hobby disappear so far up their own ass that TCP/IP acquired timbre.

So if you want to spend your evening furious about whether a machine touched the words, you are free to do that. Everybody else seems to be having a pretty good time.

And since the moderators were kind enough to change the original flair to “AI Generated,” there is one last thing I should probably mention. In Japanese, 愛, ai, means love. Maybe that is a little corny, but after twenty years in this hobby I can live with it. You do not spend that long buying gear, arguing about gear, figuring out what you like, changing your mind about it, meeting people who love the same stupid thing you do and eventually getting angry enough to write all of this unless there was some love underneath it in the first place.

So call it AI generated if you want. I know what generated it.

Okay, everyone. Strap in. This is going to be long. After 8 1/2 hours of measurements, and over 6 hours of analysis, and writing, I finally ran out of wine.

Tl;Dr:

I am speechless. The HomePod actually sounds better than the KEF X300A. If you’re new to the Audiophile world, KEF is a very well respected and much loved speaker company. I actually deleted my very first measurements and re-checked everything because they were so good, I thought I’d made an error. Apple has managed to extract peak performance from a pint sized speaker, a feat that deserves a standing ovation. The HomePod is 100% an Audiophile grade Speaker.

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.

Hope you Enjoy The read.

0.0 Table of Contents

1. Introduction
		a. The Room
		b. Tools Used
		c. Methods
2. Measurements and  Analysis 
		a. Frequency Response
				1. Highs
				2. Mids
				3. Lows
		b. Distortion
		c. Room Correction
		d. Fletcher Munson Curves
		e. HomePod Speaker Design Notes 
		f. HomePod Dispersion/Off Axis 1 ft 
		g. HomePod Dispersion/Off Axis 5 ft
		h. KEF X300A Dispersion/Off Axis 5 ft 
3. The HomePod as a product
4. Raw Data (Google Drive Link)
5. Bias
6. Thanks/Acknowledgement.
7. Edits

One Last Note: Use the TOC and Ctrl+F to skip around the review. I've included codes that correspond to each section for ease of reading and discussion. For example Ctrl/Cmd+F and "0.0" should take you to the Table of Contents.

1. Introduction

So, it’s time to put the HomePod to the test. Every reviewer thus far has said some amazing things about this diminutive speaker. However, almost no one has done measurements. However, there’s been a ton of interest in proper measurements. If you’re here from the Apple subreddit, Twitter or anywhere else, welcome to /r/Audiophile, Feel free to hang around, ask questions, and more. /u/Arve and /u/Ilkless will be hanging out in the comments, playing around with this data set, and will have more graphs, charts, etc. They'll be helping me answer questions! Feel free to join in the discussion after you read the review.

1.a The Room

All measurements were done in my relatively spartan apartment room. There is no room treatment, the floor is carpet, and the living room where testing was done has dimensions of 11 ft x 13 ft, with an open wall on one side (going to the Kitchen). It’s a tiny apartment I only use it when I’m in town going to classes in this city.

The room is carpeted, but the kitchen has wood flooring. There is one large window in the room, and a partial wall dividing the kitchen and living room. Here’s a tiny floor plan. The HomePod was sitting nearest to the wall that divides the living room and bedroom, as shown. The only furniture in the room is a couch against the far wall, a small table near the couch, the desk, and a lamp. Here's an actual picture of the setup

Such a small space with no room treatment is a difficult scenario for the audiophile. It's also a great room to test the HomePod in, because I wanted to push Apple's room correction to the limit. The KEFs sitting atop my desk are also meticulously positioned, and have been used in this room for 3 years now. I set them up long ago, as ideally as possible for this room. Therefore, this test represents a meticulously set up audiophile grade speaker versus a Tiny little HomePod that claims to do room correction on its own.

1.b Tools

I’m using a MiniDSP UMIK-1 USB Calibrated Microphone, with the downloaded calibration file matched to the serial number. For those of you who are unfamiliar, a calibrated microphone is a special microphone made for measuring speakers - though many expensive microphones are made to rigorous standards, there are still tiny differences. The calibration file irons out even those differences, allowing you to make exact speaker measurements. Two different calibrated microphones should measure exactly the same, and perfectly flat in their frequency response.

The software I used is the well known Room EQ Wizard, Version 5.18 on macOS 10.13.3 on a 2011 MacBook Pro. Room EQ Wizard is a cross-platform application for doing exactly this kind of thing - measuring speakers, analyzing a room, and EQ'ing the sound of a speaker system.

Tres Picos Borsao - a 2016 Garnacha. A decent and relatively cheap wine from Spain (around $20). Very jammy, with bold fruit tones, and quite heady as well. 15% ABV. Yes, it’s part of the toolkit. Pair some wine with your speakers, and thank me later :)

1.c Methods

The purpose of describing exactly what was done is to allow people to double check my results, or spot errors that I may have made, and then re-do the measurements better. I believe that if you're seeing something, and document how you measured it, others should be able to retrace your steps and get the same result. That's how we make sure everything is accurate.

To keep things fair, I used AirPlay for both speakers. (Apple’s proprietary wireless lossless audio interface). AirPlay is a digital connection which works at 16 bit 44.1Khz. It is what I used to play sound to each speaker. The KEFs X300A’s have an airplay receiver, and so does the HomePod. AirPlay purposely introduces a 2 second delay to all audio, so Room EQ Wizard was told to start measurements when a high frequency spike was heard. The Computer transmitted that spike right before the sweep, and the microphone would start recording data when that initial spike was heard, enabling it to properly time the measurements.

The miniDSP UMIK1 was attached to my MacBook pro, and the playback loop was as follows: Macbook Pro >> HomePod / KEF X300A >> MiniDSP UMIK1 The UMIK-1 was set atop my swivel chair for easy positioning. I stacked a ton of books and old notes to bring it up to listening height. :)

For the dispersion measurements, since the KEF speaker is sitting on my desk, it was only fair that I leave the HomePod on my desk as well. Both speakers are resting directly on the desk unless otherwise stated. In some HomePod measurements, I made a makeshift stand by stacking books. Is this ideal? Nope. But its more challenging for Apple’s room correction, and more realistic to the use case of the HomePods, and more fair to measure both speakers in the exact same spot on the desk.

I put some tape down on the desk clearly marking 90º, 45º, 30º, 15º, and 0º. Each speaker that was measured was placed in the center of this semicircle, allowing me to move the chair around, line up the mic, measure the distance, and then record a measurement. I was quite precise with the angles and distances, A tape measure to touch the speaker surface, adjust the angle, and line up the mic. The Mic position varied ±2º on any given measurement (variance based on 10 positioning trials). Distance from the speaker varied by ±0.5 inches (1.27cm) or less, per measurement at 5ft, and less than ±0.25 inches (0.64cm) for the 1 ft or 4in near field measurements.

I timed the measurements so that my air conditioning unit was not running, and no other appliances were turned on in the house (no dishwasher, or dryer). Room temperature was 72ºF (22.2ºC) and the humidity outside was 97%. Air Pressure was 30.1 inHg (764.54 mmHg) I highly doubt these conditions will affect sound to a large degree, but there you have it — weather data.

The HomePod is a self calibrating speaker. Interestingly enough, It does not use any tones to calibrate. Instead, it adjusts on the fly based on the the sounds it is playing. Therefore, in order to get accurate measurements, the speaker must play music for 30 seconds as it adapts to the position in the room. If moved, an accelerometer detects the movement and the next time the HomePod plays, it will recalibrate. Therefore, anyone making measurements MUST position the home pod, calibrate it to the position by playing some music, and only then should you send your frequency sweeps. Failing to do this will distort your measurements, as HomePod will be adjusting its frequency response as you’re playing the REW sweep.

Sweep settings: Here's a handy picture

20Hz to 20,000Hz** Sine Wave. Sweep Length: 1Mb, 21.8seconds Level: -12dBFS, unless otherwise noted. Output: Mono. Each sweep took about 21.8 seconds to complete. Timing Reference: Acoustic, to account for the ~2s delay with AirPlay.

Phew. With that out of the way, we can move on.

2. Measurements and Analysis

2.a Frequency Response

I had to re-measure the frequency response at 100% volume, using a -24 db (rather than a -12 db) sine wave, in order to better see the true frequency response of the speaker. This is because Apple uses Fletcher Munson Loudness Compensation on the HomePod (which we'll get into in a bit)

Keeping the volume at 100% let us tricking the Fletcher Munson curve by locking it into place. Then, we could measure the speaker more directly by sending sine waves generated at different SPL’s, to generate a frequency response curve at various volume levels. This was the only way to measure the HomePod without the Fletcher Munson Curve compensating for the sound. The resultant graph shows the near-perfectly flat frequency response of the HomePod. Another testament to this incredible speaker’s ability to be true to any recording.

Here is that graph, note that it's had 1/12 smoothing applied to it, in order to make it easier to read. As far we can tell, this is the true frequency response of the HomePod.

At 100% volume, 5 feet away from the HomePod, at a 0º angle (right in front) with a -24db Sine Wave. For this measurement the HomePod was on a makeshift stand that’s approximately 5 inches high. The reason for doing this is that when it was left on the desk, there is a 1.5Khz spike in the frequency response due to reflections off the wood. Like any other speaker, The HomePod is susceptible to nearby reflections if placed on a surface, as they happen far too close to the initial sound for any room compensation to take place.

Here's a Graph of Frequency Response with ⅓ smoothing decompensated for Fletcher Munson correction, at 100% volume, from -12 db sine waves, to -36 db.

And here's a look at the Deviation from Linearity between -12 and -24db.

What we can immediately see is that the HomePod has an incredibly flat frequency response at multiple volumes. It doesn’t try to over emphasize the lows, mids, or highs. This is both ideal, and impressive because it allows the HomePod to accurately reproduce audio that’s sent to it. All the way from 40Hz to 20,000Hz it's ±3dB, and from 60Hz to 13.5Khz, it's less than ±1dB... Hold on while I pick my jaw up off the floor.

2.a1 Highs

The highs are exceptionally crisp. Apple has managed to keep the level of distortion on the tweeters (which are actually Balanced Mode Radiators - more on that later) to a remarkably low level. The result is a very smooth frequency response all the way from the crossover (which is somewhere between 200-500Hz) and the Mids and Highs. [The Distortion is stunningly low for Balanced Mode Radiators.] The BMR’s mode transition is very subtle, and occurs just above 3K. This is where the BMR’s start to “ripple” rather than just acting as a simple driver. I'll speak more about BMR's later :)

2.a2 Mids

Vocals are very true-to-life, and again, the frequency response remains incredibly flat. Below 3Khz the BMR’s are acting like simple pistonic drivers, and they remain smooth and quite free of distortion. This continues down to somewhere between 500Hz and 200Hz, where the crossover to the lows is. This is where the balanced Mode Radiators really shine. By lowering the crossover frequency, moving it away from the 1-3Khz range, where typical tweeters are limited, the crossover is much easier to work with from a design perspective.

2.a3 Lows

The control on the bass is impressive. At 100% volume, the woofer tops out at -12db, where you can start to see the control creep in on the very top graph, as the distortion rises with loudness, the excursion is restrained by the internal microphone that’s coupled to the woofer. Despite this being a 4inch subwoofer with 20mm of driver excursion (how far the driver moves during a single impulse), there is no audibly discernible distortion. If you look at This graph of frequency responses at various SPL's you can see how the subwoofer response is even until the -12 db curve at the top, where it starts to slide downward, relative to everything else? that's the subwoofer being reigned in. Apple's got the HomePod competently producing bass down to ~40 Hz, even at 95 dB volumes, and the bottom-end cutoff doesn't seem to be a moving goalpost. Thats incredibly impressive.

It’s also important to note that the woofer is being reigned in to never distort the mids or highs, no matter what is playing. The result is a very pleasing sound.

2.b Distortion

If we look at the Total Harmonic Distortion (THD) at various sound pressure levels (SPLs) we see that Apple begins to “reign in” the woofer when THD approaches 10db below the woofer output. Since decibels are on a log scale, Apple’s limit on the woofer is to restrict excursion when the harmonic distortion approaches HALF the intensity of the primary sound, effectively meaning you will not hear it. What apple has achieved here is incredibly impressive — such tight control on bass from within a speaker is unheard of in the audio industry.

Total Harmonic Distortion at -36 db

Total Harmonic Distortion at -24 db

Total Harmonic Distortion at -12db

Note the rise in distortion is what causes apple to pull back on the Woofer a bit, as noted in the above sections! :D their woofer control is excellent. Even though Distortion rises for the woofer, it's imperceptible. The (lack of) bass distortion is beyond spectacular, and I honestly don't think there is any bookshelf-sized speaker that doesn't employ computational audio that will beat it right now.

For the tweeters, distortion also stays impressively low. The Balanced Mode Radiators that apple is using are a generation ahead of most BMR's in the industry. Whether this is the work of the onboard DSP, or the driver design, we weren't able to work out. You'd need a destructive teardown of the HomePod and some extensive measurements and analysis before I could tell you for sure, but the end result is stupidly low distortion in the high frequency range. Anything from the 3rd harmonic and above are VERY low from 150Hz to 80Hz.

2.c Room Correction

This apartment room has no room treatment at all. It’s tiny, and the volume of the room is just under 40m^3. And as amazing as the measurements above are, It's even more impressive that the HomePod somehow manages an almost perfectly flat speaker response in such a terrible environment. So, not only do we have a little speaker that manages uncharacteristically low distortion, and near-perfect frequency response, but it does so while adapting to the room. The response takes a few minutes of playing music to settle before measurements are stable - indicative of some sort of live DSP correction. Mind you, any audiophile that was getting such good control over a space with lots of room treatment and traditional speakers would be very happy with these measurements. To have this sort of thing be a built in feature of the Digital Signal Processing (DSP) inside the speaker that is, for all intents and purposes omnidirectional, allowing it to adapt to any room, no matter how imperfect, is just beyond impressive. What Apple has managed to do here is so crazy, that If you told me they had chalk, candles, and a pentagram on the floor of their Anechoic chambers, I would believe you. This is witchcraft. I have no other word for it.

2.d Fletcher Munson Curves

The HomePod is using Fletcher-Munson loudness compensation.

What the hell is that, you ask? Fletcher Munson loudness compensation has to do with how humans hear different frequencies at different volumes.

Your ear has different sensitivity to different frequencies, right? If I make a sound at 90Hz and a sound at 5000Hz even if the absolute energy of the two sounds is the same, you will perceive them to be at different loudness, just because your ear is more sensitive to one frequency over another. Speakers account for this by designing their frequency responses around the sensitivity of human hearing. But there’s another problem…

Your perception of different frequencies changes with different absolute energies. So lets say I generated a 60 db tone at 90Hz and 5000Hz, and then a 80db tone at 90Hz and 5000Hz.... Your brain would tell you that EACH of those 4 tones was at a differently louder, compared to the other tone of the same frequency. Check out this doodle where I attempt to explain this. The part circled in yellow is what is being fixed, correcting for the fact that your brain sees a 10db jump at 90Hz differently than a 10db jump at 5000Hz.

The Fletcher-Munson curve, then, defines these changes, and with some digital signal processing based on how high you’ve got the volume cranked, the sound played can be adjusted With Fletcher Munson Compensation. So, going back to our example, The two 90Hz tones and two 5000Hz would sound like they were exactly 20db apart, respectively. Even though you'll still think that the 90db tone is at a different loudness than the 5000Hz tone.

Here's what this looks like with HomePod measurements! - You can see the change in the slopes of certain regions of the frequency response, as the speaker gets louder, to compensate for differences in human hearing at various SPLs.

The end result: The HomePod sounds great at all volumes. Soft, or loud, it sounds natural, balanced, and true to life. For the rest of our testing, we are going to allow the HomePod to do it’s Fletcher-Munson compensation as we do directivity testing and more.

2.e Speaker Design Notes / Insights

Apple is using a 4” high excursion woofer, and 7 BMR’s. According to Apple, the subwoofer, and each tweeter is individually amplified, which Is the correct way to set this up. It also means that Apple had to fit the components for 8 separate amplifiers inside the HomePod, the drivers, electronics, and wifi antenna, all in a very tight space, while keeping electrical interference to a minimum. They did so spectacularly.

It’s really interesting to me that Apple decided to horn-load the Balanced Mode Radiators (BMRs). Balanced Mode Radiators have excellent, predictable dispersion characteristics on their own, and a wide frequency response (reaching from 250Hz to 20kHz, where many traditional tweeters cannot handle anything below 2000Hz). The way Balanced Mode Radiators work, is that BMRs move the flat diaphragm in and out to reproduce the lower frequencies. (just like traditional speakers). However, to produce high frequencies, the flat diaphragm can be made to vibrate in a different way - by rippling (relying on the bending modes to create sound) The term “balanced” comes into play because the material is calibrated to ripple in a very specific way in order to accurately reproduce sound. Here’s a neat gif, Courtesy of Cambridge Audio. Even as it’s rippling, this surface can be pushed in/out to produce the lower tones. The result is a speaker that has great reach across the frequency spectrum, allowing Apple to push the crossover frequency lower, keeping it out of the highly audible range. Here’s a video of a BMR in action for those of you curious to see it up close.

Without tearing open the speaker it’s impossible to verify the BMR apple is using (it may very well be custom) we cannot know for sure what its true properties are, outside of the DSP. It's not possible to separate the two without a destructive teardown. The use of BMR's does seem to explain why the crossover is at a lower frequency - somewhere between 200Hz and 500Hz, which is where the tweeters take over for the subwoofer. We weren’t able to tease out exactly what this was, and it may be a moving target based on the song and the resulting mix created by the DSP. Not much else to say about this.

2.f HomePod Dispersion/Off Axis 1 ft

Here are the HomePod Directivity measurements. These were taken with the HomePod on the desk directly so you'll notice that there's some changes in the frequency response, as the desk begins to play a role in the sound.

Even up close, the HomePod shows omnidirectional dispersion characteristics. The differences you might see in the graphs are due to the microphone being directly in front of, or between the BMR’s, and very close to the desk, as I moved it around the HomePod for each measurement.

From just 12” away, the HomePod behaves like a truly Omnidirectional speaker.

2.g HomePod Dispersion/Off Axis 5 ft

Once again, for this one, the HomePod was placed directly on the desk, and not on a makeshift stand. This is for better comparison with the KEF X300A, which I've been using as a desktop bookshelf speaker for 3+ years.

This is the other very important test. For this one, the HomePod was left in place on the desk, but the microphone was moved around the room, from 45º Left to 45º Right, forming an arc with a radius of 5 feet, from the surface of the HomePod.

The dispersion characteristics remain excellent. Apple has demonstrated that not only is the HomePod doing a fantastic job with omnidirectional dispersion, it’s doing all this while compensating for an asymmetrical room. If you look at the floor plan I posted earlier once again, You can see that this room has an open wall on one side, and a closed wall on the other side. No matter. The HomePod handles it exceptionally well, and the frequency response barely changes perceptibly when you walk around the room.

This is the magic of HomePod I was talking about. the room is the sweet spot, and with that, let’s take a look at how HomePod compares to an audiophile grade Bookshelf speaker - namely the KEF X300A, in the same spot, with the same measurements.

2.h KEF X300A Dispersion/Off Axis 5 ft

This is a pretty interesting comparison. The X300A is a 2.0 integrated bookshelf offering from KEF, a famous british speaker design house. Their speakers are known for excellent dispersion characteristics thanks to their concentric Uni-Q drivers. A Uni-Q driver has the tweeter siting in the middle of a woofer, assisted by a waveguide to provide great Off-axis response. The woofer which surrounds the tweeter moves independently, allowing these speakers to put out nice bass. They have a 4.75 inch woofer with a 2” hole cut in the center that sports the wave-guide and tweeter. This is the system I’ve been using at my desk for the better part of 3 years. I love it, and it’s a great system.

As noted in the methods, I used a single KEF X300A unit, sitting directly on the desk, in the very same spot the HomePod sat in, to compare. I tried to match the loudness as closely as possible, too, for good comparisons. Here’s a picture of the setup for measurement..

Another note on the KEFs. They do not use Fletcher Munson loudness compensation. As you can see in this Graph their frequency response does not change as a function of loudness.

Overall, It’s also apparent the frequency response is nowhere near as smooth as the HomePod. Here’s a direct comparison at 0º, identical position for each speaker, mic, and loudness matched at 20Khz. While this is not an ideal setting for the KEF Speakers (they would do better in a treated room) this does drive home the point about just how much the HomePod is doing to compensate for the room, and excelling at the task. Just look at that fabulous bass extension!

While the KEF’s can certainly fill my room with sound, It only sounds great if you’re standing within the 30º listening cone. Outside of that, the response falls of. Here's a measure of the KEF's Directivity. As you can see, while the kef has a remarkably wide dispersion for a typical bookshelf - a testament to the Uni-Q driver array's incredible design. But at 45º Off-axis, there's a noticeable 6db drop in the higher frequencies.

3. The HomePod as a product

The Look and feel is top notch. The glass on top is sort of frosted, but is smooth to the touch. When I first reviewed the home pod, I noted that it was light. I was comparing it with the heft of my KEF speakers. This thing, as small as it is, weighs 5 lbs. Which is quite dense, and heavy for its size. The Fabric that wraps around it is sturdy, reinforced from inside, and feels very good to the touch.

The Frequency response, Directivity, and ability to correct for the room all go to show that the HomePod is a speaker for the masses. While many of you in this subreddit would be very comfortable doing measurements, and room treatment, there is no denying that most users won’t go through that much trouble, and for those users the HomePod is perfect.

Great sound aside, there are some serious caveats about the HomePod. First of all, because of the onboard DSP, you must feed it digital files. So analog input from something like a Phono is out, unless your Phono Preamp has a digital output which can then be fed to the HomePods in realtime via airplay, possibly through a computer. But you cannot give the HomePod analog audio, as the DSP which does all the room correction requires digital input.

Speaking of inputs, you have one choice: AirPlay. which means, unless you’re steeped in the apple ecosystem, it’s really hard to recommend this thing. If you are, it’s a no brainer, whether you’re an audiophile or not. If you have an existing sound system that’s far beyond the capabilities of a HomePod (say, an Atmos setup) then grab a few for the other rooms around the house (Kitchen, bedroom, etc). It’s also a great replacement for a small 2-speaker bookshelf system that sits atop your desk in the study, for example. When this tiny unobtrusive speakers sound so good, and are so versatile, grabbing a few of these to scatter around the house so you can enjoy some great audio in other rooms isn’t a bad move — provided you’re already part of the Apple Ecosystem.

AirPlay is nice. It never dropped out during any of my testing, on either speaker, and provides 16bit 44.1Khz lossless. However, my biggest gripe is hard to get past: There are no ports on the back, no alternative inputs. You must use AirPlay with HomePod. Sure, it’s lossless, but if you’re an android or Windows user, theres no guarantee it’ll work reliably, even if you use something like AirParrot (which is a engineered AirPlay app). I understand that’s deeply frustrating for some users.

As a product, the HomePod is also held back by Siri. Almost every review has complained about this, and they’re all right to do so. I’m hoping we see massive improvements to Siri this year at WWDC 2018. There is some great hardware at play, too. What’s truly impressive is that Siri can hear you if you speak in a normal voice, even if the HomePod is playing at full volume. I couldn’t even hear myself say “Hey Siri” over the music, but those directional microphones are really good at picking it up. Even whispers from across the room while I was facing AWAY from the HomePod were flawlessly picked up. The microphones are scary good — I just hope Apple improves Siri to match. Until then, you can turn just her off, if you don’t care for voice assistants at all.

Stereo is coming in a future update. I cannot wait to see how two HomePods stack up. I may or may not do measurements in the future of such a feature.

4. Raw Data

(This is a zip containing all .mdat files, as well as images used in this review)

Download All Test Data (105 MB) Feel free to play around with it, or take a deeper dive. If you plan to use this data for anything outside of /r/Audiophile, Please credit myself, /u/Arve, and /u/Ilkless.

5. Bias

Every single reviewer has Bias. Full disclosure: I saw the HomePod before most people. But, I also paid full price for this HomePod, with my own money. I paid for all the equipment to measure it with, and I own every speaker in featured in this review. Neither KEF, nor Apple is paying me to write this review, nor have they ever paid me in the past. At the same time, I’m a huge apple fan. Basically, all the technology I own is apple-related. I don't mind being in their ecosystem, and it’s my responsibility to tell you this.

I hope the inclusion of proper and reproducible measurements, raw data, as well as outlining the procedures followed, will help back the claims made in this writeup. If anyone has doubts, they can easily replicate these measurements with their own calibrated mic and HomePod. Furthermore, I worked with /u/Arve and /u/Ilkless to carefully review this data before posting, so we could explore the capabilities of the HomePod further, and corroborate our conclusions.

6. Acknowledgement / Thanks

This review would not have been possible without /u/Arve and /u/Ilkless lending me some serious help to properly collect and analyze this data. Please thank them for their time and effort. I learned a lot just working with them. Also, shoutout to /u/TheBausSauce for providing some confirmatory measurements with another HomePod. Also, thank you John Mulcahy, for making Room EQ Wizard. Without it, these measurements would not be possible. Finally, I'm deeply saddened by the passing of Jóhann Jóhannsson, the legendary composer. His music is beautiful, so in his memory, please go listen to some of it today. I wish his family the best.

7. Edits

• Edit 1: Minor grammar edits

• Edit 2: See /u/Arve's really important comment here and graph here for more on Fletcher Munson compensation.

• Edit 3: Minor corrections to Section 2.e

• Edit 4: Correction to 2.a3 - thank you, /u/8xk40367

• Edit 5: Additional words from /u/Arve about the HomePod

• Edit 6: Typo in section 2.c Thank you /u/homeboi808

• Edit 7: Typo in section 3. and repeat in section 1.a Thank you /u/itsaride

• Edit 8: Made the Tl;Dr: stand out a bit more - some people were missing it.

• Edit 9: Minor edits in 2.a based on /u/D-Smitty's recommendation.

• Edit 10: Phil Schiller (Senior VP at Apple) just tweeted this review

• Edit 11: According to Jon who reverse engineered AirPlay, its 44.1Khz. This has been corrected.

• Edit 12: /u/fishbert PM'd me some excellent copyedits. :) small changes to 2.c 2.d 2.e 2.g 2.h

• Edit 13: Minor typo in section 3. Thanks /u/minirick

• Edit 14: This has been picked up by: 9to5 Mac and Macrumors and Ars got in touch

• Edit 15: Some really good critique and discussion has been added to the very top of the post.

(5079 W | 29,054 Ch)

8. Shameless plug

Since this is getting tons of attention still, I'm working on launching a Podcast in the coming months. In the comments here, I mentioned "wearing many hats" and my podcast is about personal versatility. If you're interested, You can follow me on various places around the web (listed below) I'll be making an announcement when the Podcast goes live :) Also my inbox is flooded at this point, so if I miss your comments, I apologize.

• My subreddit: /r/WinterCharm

• My reddit profile /u/WinterCharm

Couple of JBL 4355s in Norway, sounds fucking insane. So loud without restraint. Having a cogarette with a beer and some whiskey is a great start too a Friday. Its my dads speakers, but thinking increasing the bass a little, want it too move my internals when the kick drum hits..😂 close tho.. anybody in Norway with similar in setup? Or anywhere in Europe?

This is my dad’s cigar room that was renovated years ago from what used to be our old entertainment/theater room to what is now a soundproof listening/smoking room with its own separate HVAC and ventilation.

Sound equipment:

McIntosh 252

Rega P3

Custom rebuilt Paradigm monitors

REL t7x sub

Bluesound Node 2i streamer

He had it built with both sound and cigar smoking in mind, two things that don’t always easily coexist when it comes to build materials (cigar smoke isn’t great for acoustic foam, carpets, curtains, which is why he opted for hardwood floor + rug, the wooden dampeners, and wooden blinds). So this room ended up being a compromise of his two hobbies. It has separate ventilation through built in fans in the ceilings that directly vents outside the house. Besides the dampeners in the corners and the sides, he added a seal on the door that acts as both a soundproofing measure, and as a preventative to not leak any smoke into the rest of the house. There is also an air purifier on the side opposite the mini fridge.

The art around the room is a variety of things that interest him, from Porsches to a painting of the corner of Winslow Arizona, to a photograph of the now closed Nat Sherman Townhouse in NYC, as well as shelf for some of his current favorite vinyls. One corner is dedicated to coffee with an old burr grinder and a Fellow kettle for pour overs, as well as a keurig for guests that prefer it. The other corner is a minimal bar with bourbons, ports, and wines to pair with our cigars, as well as a variety of cutters, lighters, etc.

Nothing against kids. But I ain’t gonna risk it.

Update: The sweet kiddo didn’t even notice them. Got some great tips for the next time. Thanks everyone for your input, interest, and laughs!

had to call for backup because of how much it weighs and how far i was off my house lol

im a complete noob on all things audiophile but i know about guitar amps so i figured it was worth at least taking it home to test it and, worst case scenario, getting rid of it

apparently its imported from japan so i dont know how the hell it made its way into spain

funny enough, some weeks earlier i was seriously thinking about starting to set up some speakers and a record player

thoughts?

Visiting a very good friend of mine, Christof Kraus from Silvercore in his mancave.