
Hacking the Sonos IKEA Symfonisk into a High Quality Speaker Amp - mochtar
https://makezine.com/2019/08/16/hacking-the-sonos-ikea-symfonisk-into-a-high-quality-speaker-amp/
======
snops
Quite dangerous to leave this without an enclosure, since the power supply is
on the same PCB, several of the components and solder points carry mains
voltage.

I'm surprised an outlet as high profile as Make don't at least recommend one,
or have any of the usual warnings about high voltage.

On a side note, it's no mean feat integrating large through hole components
and tiny SMD parts onto the one PCB, normally power supplies are wave soldered
while SMD parts need reflow instead, and hence TVs and the like use seperate
PCBs. Pin-in-paste[1] is possible, but only with some parts, so maybe they
used automated selective soldering[2] instead?

[1] [https://www.7pcb.com/blog/the-application-of-the-pin-in-
past...](https://www.7pcb.com/blog/the-application-of-the-pin-in-paste-reflow-
process.php)

[2] [https://www.nordson.com/en/divisions/select/soldering-
proces...](https://www.nordson.com/en/divisions/select/soldering-
processes/selective-vs-wave-soldering)

~~~
sowbug
From TFA: "... maybe build yourself a nice enclosure for the electronics ..."

~~~
Bluestrike2
At the very end. It also uses the word "maybe" to equivocate on the subject,
and describing it as a "nice enclosure" both minimizes the importance and
avoids mentioning the _very_ dangerous risks. The sentence assumes prior
knowledge on the part of the reader, which even for a site like Make, isn't
always the case. People without that knowledge, who weren't necessarily the
intended audience, find their way to these sorts of tutorials as well.

That doesn't detract from the article's interestingness by any means, but
pointing out at least some of the risks is the sort of thing that should
happen more often in them. The off-hand way in which the enclosure was
mentioned detracts a bit, in my mind, from an otherwise interesting article.
Maybe I'm overthinking things a bit.

------
groundlogic
IKEA seem to be killing it in speaker area these days. Even as Swede, that's
kind of unexpected. I guess they saw a market segment where a lot of wood is
used (this one's plastic though), and there were high margins for the premium
products and then decided to go for it.

There's obviously a great deal of outsourcing to chinese and taiwanese
manufacturers going on here, but they seem to be very competent in the
customer role.

I love my IKEA Eneby BT speaker from last year. (This one, with the add-on
battery:
[https://www.ikea.com/us/en/catalog/products/00357636/](https://www.ikea.com/us/en/catalog/products/00357636/))

I would love for IKEA to go into the standalone analogue speaker segment with
a fantastic living room speaker, just to piss off those (often) European and
quite pretentious speaker brands. Take on B&W and the likes!

~~~
bjoli
Eneby is one hell of a speaker for the price. I use a the one you linked to at
work for "play along" when a practicing new pieces for the orchestra. Before
it I had a hard time finding a portable speaker with enough pinch and battery
life with a reasonable price.

------
leoedin
This is cool! I wonder if you connected just one of the audio outputs to a
speaker with a crossover, the system would adjust to put the whole frequency
range through it?

It may also be that there's somewhere on the pcb you can tap into line level
full frequency audio (or maybe not - they could easily do the filtering only
in the digital domain)

One thing to keep in mind when doing this is the impedance of the speakers.

I'd measure the resistance across the IKEA ones and whatever speakers you're
using first. It may be that the IKEA ones are not the common 8 ohms. If
they're more (eg 16 ohms) there's a risk that an 8 ohm speaker will result in
too much current through the amplifier.

~~~
phasetransition
A speakers' impedance has substantial reactances, and the nominal ohmic
ratings have little practical meaning.

Almost all modern class D amplifier ASICS have short circuit protection on
their outputs

------
aaronbrethorst
Fun fact: the author of this piece, Ben Hobby, is the son of David Hobby, the
photographer who maintains Strobing, one of the best blogs on off camera
lighting:
[https://strobist.blogspot.com/?m=1](https://strobist.blogspot.com/?m=1)

~~~
war1025
Really thought this post was going to somehow circle around to Hobby Lobby as
I was reading it.

~~~
labster
Nope, but you can read it while your plane is circling around Houston Hobby
airport.

------
rubatuga
Most wireless speakers released nowadays have a digital EQ to compensate for
differences in frequency response to simulate accuracy. However the fact that
this EQ is now being utilized on a different set of speakers makes this build
far from "high quality".

~~~
janwh
While the little hack is surely fun, this is an underrated comment. The tuning
that SONOS speakers do at setup will also not help if the speaker's own signal
characteristics are taken into account for generating the system transfer
function between input signal, speaker, and room. That's how SONOS, BOSE, et
al. achieve a consistent sound in the first place.

So the result with different speakers will be mediocre at best and indeed far
from high quality, even with a high quality speaker strapped on to it.

------
phasetransition
There's very little chance that the crossover filter topology, as well as any
biquads in either bandpass are appropriate for a two way loudspeaker other
than the original.

Solid looking unit from the teardown, I might have to get one...

------
syntaxing
This is really awesome! Is there any issues with the mismatch of inductive
resistance/impedance of the bookshelf speaker vs the original speakers? I
would imagine the board is designed for a very specific ohm range.

------
MrBuddyCasino
Anyone knows how much power that amp can source? Impossible to find any
numbers.

~~~
teknopaul
He turned a speaker amplifier into a speaker amplifier.

He just pluged in the speaker cables into a different speaker. Started with a
speaker and amp all in one box, and a speaker needing an amp. Ended up with a
speaker and separate amp in bits on the table, and, if he screws the sonos box
back together, a speaker that now needs an amp.

He is now wondering about building a box for this amp. ;)

I would recomend he put the bits back in the box they came in!

Pretty pointless. I've dont the opposite "hack" of mounting amps inside
passive speakers, saves on untidy cables.

If you want an external amp for your speaker. Well, go buy one: when you buy
it, they will tell you the numbers :)

~~~
ed
> If you want an external amp for your speaker. Well, go buy one: when you buy
> it, they will tell you the numbers :)

Sonos Amp costs $599, so this is an interesting alternative.

[https://www.sonos.com/en-us/shop/amp.html](https://www.sonos.com/en-
us/shop/amp.html)

------
yayr
What would it take to connect those two outlets to the line ins of a sub /
speaker?

~~~
KozmoNau7
You would have to take the line-level signals from before the power amps, and
the crossover is probably around 2500-3500Hz, way too high for a subwoofer.

------
baybal2
It looks so much of an overkill on the digital side. A fully fledged SoC with
PCI Express and standalone WiFi NIC just to do network, and audio decode?

Chinese factories make such Internet radios on $2 Espressif or Realtek
microcontrollers.

~~~
chendragon
It looks like the processor is doing some form of DSP, so some smarts are
required. It can also play from Spotify etc. and the binaries for that are
probably bloated like most cloud services.

With this said, had this been a lower end product, the SoC would probably have
been an Allwinner or MTK with a soldered Realtek SDIO WiFi solution.

~~~
Marsymars
> It can also play from Spotify etc. and the binaries for that are probably
> bloated like most cloud services.

One of my favourite things about my Sonos setup is that it avoids me having to
run bloated cloud service binaries on my personal computing devices. (Most
notably, of the services I use, SiriusXM digital services have always been
most unpleasant to use.)

~~~
Gwypaas
That's what made me ditch sonos 4 years ago. Being forced to run everything
through the awful Sonos app instead of casting from the dedicated app or
playing through Bluetooth without any delays.

~~~
Marsymars
Last I checked, the Sonos app is better than the SiriusXM app. Not that I use
it much anyway, I mostly use Sonos/Sirius via Alexa control.

------
cushychicken
Clever. Don't go frying the amp hooked up to those big towers. :)

~~~
mschuster91
IIRC the only way to fry an amp is to hook it up with no load. Putting not
enough load will fry the load when the amp overdrives it, putting too much
load will simply make for a quiet speaker.

~~~
markus92
Really dependance on the kind of amp you tot. For older tube amps, this is a
major concern indeed because they drive by current, not voltage, thus
exploding the voltage when there’s no path for the current to flow. Modern
class D amps don’t have this problem, those just hate short circuits as they
drive by voltage.

------
rurban
Wasn't SONOS already exposed for being a CIA front? Like streaming the audio
encrypted to a receiver station. I would have expected the hacker looking into
this instead.

~~~
Gys
This speaker is conspiracy-theory-proof: it has no microphone

~~~
rurban
You don't know. Traffic is encrypted and articially enlarged with some spooky
Mesh Networking talk.

And one of the founders got caught.

------
davidy123
I find it odd to have a hacker project that connects to a proprietary
ecosystem (Sonos). In general, I'm disappointed that Ikea went with Sonos,
it's not very "people and planet" to be dependent on one company and app to
enable different sound ecosystems, without even a Bluetooth option.

~~~
crooked-v
I don't think there's any alternative open standard that can do what Sonos
does - group speakers arbitrarily, do line-in without requiring separate
computers/phones, auto-balance speaker volume/lag for room positioning, have
the same speaker set switch between surround sound and other inputs with
minimum hassle, etc, and all wirelessly without a specific server hub needed.

There are proprietary competitors (Alexa is moving into that space, and Bose
has an even more expensive equivalent), but nothing to allow true interop, and
Ikea trying to build out that same functionality from scratch would take huge
effort and expense, certainly a lot more than the simple-by-comparison
requirements of smart bulbs.

Personally, I'd be happy to see Apple eat everyone's lunch here (they're
already partway there with arbitrary speaker output from arbitrary input
devices), but that's mostly because there's preexisting homebrew that will
that bridges arbitrary speakers to virtual Airplay devices and arbitrary input
to virtual Airplay streams.

~~~
MrBuddyCasino
> preexisting homebrew that will that bridges arbitrary speakers to virtual
> Airplay devices

Got a recommendation?

~~~
crooked-v
Some examples, including both software and dedicated hardware options:

[https://www.makeuseof.com/tag/4-airplay-receivers-that-
are-c...](https://www.makeuseof.com/tag/4-airplay-receivers-that-are-cheaper-
than-apple-tv/)

[https://github.com/philippe44/AirConnect](https://github.com/philippe44/AirConnect)

[https://www.airserver.com/](https://www.airserver.com/)

