Apple's new 1 liter speaker: 10mm xmax woofer, 8 amps, 7 tweeters w/horn, 6 mics

[Paul Carmody]

Perhaps someone can clarify this for me. I can't figure out what's going on with the tweeters. Are they all firing outward? Or are they all firing inward into that horn?

[mattsk8]

Perhaps someone can clarify this for me. I can't figure out what's going on with the tweeters. Are they all firing outward? Or are they all firing inward into that horn?

See bold, underlined from post #1...

Take a look at HomePod, Apple's new speaker. They really showed all of us how much they can pack inside a small speaker. It is remarkable what they fit inside a speaker with less than 1 liter of enclosure volume. There's some serious technology inside too.

[ATTACH=CONFIG]n1334287[/ATTACH]

There are:

- 8 amplifiers
- 7 tweeters in a unique downfiring horn with adjustable directivity
- 6 microphones
- 4" woofer with 10mm of excursion
- Wi-Fi, DSP
- fully enclosed!

A lot of interesting things about this speaker.

1. Apple somehow made 7 tweeters fire into a horn, that fires downwards to the very surface it is sitting on, and still provide variable directivity control.
2. Voices are automatically filtered to have a narrow directivity. How low are the tweeters playing?
3. Is the hardware on top of the woofer also acting as a lens to radiate the higher frequencies omnidirectionally when the woofer starts narrowing?
4. The woofer is somehow radiating sound outside when it is completely buried inside the speaker

Very curious to hear this when it comes out in December.

[mattsk8]

And like Amazon's Echo and Google's Home, it is listening to everything you say, and sending that to a giant computer farm which may or may not be recording everything you say, but is undoubtedly analyzing.

Not that I would willfully sign up to have something like Amazon Alexa monitor me, my wife, my kids, etc... but unfortunately your cell phone is already doing that anyhow (as well as constantly monitoring your location... regardless of whether or not your GPS is turned on or off in your phone). For example... a few days ago I was getting a painter situated at a condo my mom is going to sell. My GPS is always off in my phone unless I need it to use maps. Just yesterday, the neighbor girl that lives in the same condo pops up in my Facebook "recommended friends" area. I've never posted anything about this place on FB, and I've never talked to this girl or anyone she knows except for the one time I was at that condo 3 days ago. I also don't know anyone she knows... and "coincidentally" 2 days later she's a recommended friend on FB? While I have nothing to hide, it pi$$es me off to no end that they monitor (and track) everything I do and say. Am I the alone in that??

[Wolf]

This is yet another reason why I still use a 'dumb' flip-phone....
Wolf

[Sydney]

... Am I the alone in that??

And yet some embrace that; An Urban Outfitters app tracks location and informs users of deals when close to and entering their stores ( ie the movie Minority Report )

[Paul Carmody]

See bold, underlined from post #1...
- 7 tweeters in a unique downfiring horn with adjustable directivity

That's what I thought I read. But that makes no sense to me. How can firing something into a horn give it directivity, other than that of the flare of the horn itself? This is the part that I admit I'm not much of a waveguide expert. However, in my experience the only times I've seen multiple drivers pointed into a horn, it was for purposes of increased SPL, not to change directivity.

Waveguide experts, feel free to chime in here.

[wogg]

That's what I thought I read. But that makes no sense to me. How can firing something into a horn give it directivity, other than that of the flare of the horn itself? This is the part that I admit I'm not much of a waveguide expert. However, in my experience the only times I've seen multiple drivers pointed into a horn, it was for purposes of increased SPL, not to change directivity.

Waveguide experts, feel free to chime in here.

No waveguide expert, but I'm suspecting they're doing some DSP adjustment on the individual tweeters to control dispersion, kind of like beam-forming for RF.

[Sydney]

No waveguide expert, but I'm suspecting they're doing some DSP adjustment on the individual tweeters to control dispersion....

yeah Amplitude and/or Phase shading adjustment

[300Z]

Not that I would willfully sign up to have something like Amazon Alexa monitor me, my wife, my kids, etc... but unfortunately your cell phone is already doing that anyhow (as well as constantly monitoring your location... regardless of whether or not your GPS is turned on or off in your phone). For example... a few days ago I was getting a painter situated at a condo my mom is going to sell. My GPS is always off in my phone unless I need it to use maps. Just yesterday, the neighbor girl that lives in the same condo pops up in my Facebook "recommended friends" area. I've never posted anything about this place on FB, and I've never talked to this girl or anyone she knows except for the one time I was at that condo 3 days ago. I also don't know anyone she knows... and "coincidentally" 2 days later she's a recommended friend on FB? While I have nothing to hide, it pi$$es me off to no end that they monitor (and track) everything I do and say. Am I the alone in that??

What kind of phone do you have?

[mattsk8]

What kind of phone do you have?

Samsung S7

[Sydney]

Smokin'
( Don't fall asleep on it )

[mattsk8]

That's what I thought I read. But that makes no sense to me. How can firing something into a horn give it directivity, other than that of the flare of the horn itself? This is the part that I admit I'm not much of a waveguide expert. However, in my experience the only times I've seen multiple drivers pointed into a horn, it was for purposes of increased SPL, not to change directivity.

Waveguide experts, feel free to chime in here.

The first thing I thought of when I read that and saw the speaker was the B&O Beolab 90 just because of the crazy DSP that iThingy must have in it to <supposedly> manipulate the directivity the way it says it does. It would be a lot of fun to play with a horn like that... put about 5 full range speakers in a horizontal array around the inside of a horn and play with the volume levels of each driver to see how it effects the directivity of the response exiting the horn. Go from there and manipulate the angles of each of the drivers in the horn... then play with different driver positions in the horn. Someday... when I retire...

[mattsk8]

Smokin'
( Don't fall asleep on it )

Haha, the one that blew up wasn't the S7, that was the Note 7. Still, it was definitely some bad publicity for Samsung.

[rpb]

Not that I would willfully sign up to have something like Amazon Alexa monitor me, my wife, my kids, etc... but unfortunately your cell phone is already doing that anyhow (as well as constantly monitoring your location... regardless of whether or not your GPS is turned on or off in your phone). For example... a few days ago I was getting a painter situated at a condo my mom is going to sell. My GPS is always off in my phone unless I need it to use maps. Just yesterday, the neighbor girl that lives in the same condo pops up in my Facebook "recommended friends" area. I've never posted anything about this place on FB, and I've never talked to this girl or anyone she knows except for the one time I was at that condo 3 days ago. I also don't know anyone she knows... and "coincidentally" 2 days later she's a recommended friend on FB? While I have nothing to hide, it pi$$es me off to no end that they monitor (and track) everything I do and say. Am I the alone in that??

I was looking at a car at a dealership last week, and was told there was a phone app that could tell you where the car is, where it went, and how fast it was going. So, you can track what your spouse, or kids did with the car. That's a car that I will never own!

[bcodemz]

That's what I thought I read. But that makes no sense to me. How can firing something into a horn give it directivity, other than that of the flare of the horn itself? This is the part that I admit I'm not much of a waveguide expert. However, in my experience the only times I've seen multiple drivers pointed into a horn, it was for purposes of increased SPL, not to change directivity.

Waveguide experts, feel free to chime in here.

That's what I don't understand either. This is my theory on it. The 7 tweeters firing inside the horn is actually really smart, because it significantly reduces the distance between each tweeter. The horn isn't so much acting like a horn, but more as a reflector, like a mirror. The 7 tweeters will play and form a narrow directivity INSIDE the horn. Therefore, the sound is already reduced to a narrow beam inside the horn, and it just gets reflected inside the horn until it is reflected outside, where it still maintains the directivity that it achieves inside.

The first thing I thought of when I read that and saw the speaker was the B&O Beolab 90 just because of the crazy DSP that iThingy must have in it to <supposedly> manipulate the directivity the way it says it does. It would be a lot of fun to play with a horn like that... put about 5 full range speakers in a horizontal array around the inside of a horn and play with the volume levels of each driver to see how it effects the directivity of the response exiting the horn. Go from there and manipulate the angles of each of the drivers in the horn... then play with different driver positions in the horn. Someday... when I retire...

I want to make a point that what Apple/B&O is doing to achieve variable directivity is far more complicated than an amplitude/phase shading arrangement. It is way more complicated than you can ever imagine. I do some crazy stuff for my speakers, but this is an order of magnitude more complicated than even what I do.

Best way to give an idea what it takes. Suppose you have a tweeter, you can use a second tweeter placed on the left to cancel out sound from the left of the main tweeter. Doing that is incredibly tricky by itself in order to get the frequency vs phase right for every frequency while accounting for the directivity vs frequency change of the tweeter and some other problems.

But now there is sound to the left of the second tweeter. So we use a third tweeter placed to the left of the second tweeter and do the same thing. But now you gotta make sure what you do on the third tweeter do not affect the response of the first tweeter.

Now imagine doing that for 7 tweeters, and having to account for 6 other tweeters while getting its own response correctly.

Now you finally got it right for one dispersion pattern. But remember, this is *variable directivity*. Now repeat that and do it for a bunch of different dispersion patterns.