View Full Version : Squeezebox Boom Audio Design White Paper
For folks looking for some detailed technical background on the audio design in Squeezebox Boom, Caleb wrote a very interesting white paper, which has been posted to the wiki here:
http://wiki.slimdevices.com/uploads/a/ad/Logitech_Squeezebox_Boom_Audio_Design.pdf
For folks looking for some detailed technical background on the audio design in Squeezebox Boom, Caleb wrote a very interesting white paper, which has been posted to the wiki here:
http://wiki.slimdevices.com/uploads/a/ad/Logitech_Squeezebox_Boom_Audio_Design.pdf
Just as a support: This is DEFINITELY worth reading :-)
I'm curious; who was this white paper originally aimed at? It contains a lot of excellent information, including some technical details, but is written in a fairly informal fashion. Was it meant for senior management? The press? The punters? :-)
I'm curious; who was this white paper originally aimed at? It contains a lot of excellent information, including some technical details, but is written in a fairly informal fashion. Was it meant for senior management? The press? The punters? :-)
I don't know the exact target, but Caleb put it together to hand out to the Press and Gadget Junkies at the IAF Squeezebox Boom Annoucement. So speaking of the Press, I guess that includes Punters!
Very interesting read!
Greetz surly
Wow! I love this paper!
Being so open and informative about internals of the latest squeeze device will certainly gain a lot of reputation.
My personal opinion: I'm considering this art (of engineering) - hats off to those artists, hmm, engineers :-)
kudos,
Markus
P.S. I think i should go buying a copy of this artwork...
It was intended to explain all the cool audio stuff we put into the Boom.
Obviously, we can't put all this stuff into marketing materials, but for the
interested reader it explains much more in-depth why the Boom sounds so
good.
It was largely intended for the press, but also so I don't have to explain
the same thing over and over.
The informal tone is just my writing style -- no need to make things
unnecessarily sterile. (Did you ever try to read Nature or Science? It's
no fun for me.)
-Caleb
On Thu, Aug 28, 2008 at 9:19 PM, simbo <
simbo.3evarb1219951204 (AT) no-mx (DOT) forums.slimdevices.com> wrote:
>
> I'm curious; who was this white paper originally aimed at? It contains a
> lot of excellent information, including some technical details, but is
> written in a fairly informal fashion. Was it meant for senior
> management? The press? The punters? :-)
>
>
> --
> simbo
> ------------------------------------------------------------------------
> simbo's Profile: http://forums.slimdevices.com/member.php?userid=11481
> View this thread: http://forums.slimdevices.com/showthread.php?t=51599
>
>
Being in the control system business (closely related to the signal processing field, pun intended), I'm curious about the SW development environment for the Boom - what tools were used to design the filters and crossovers, were the filters implemented in the DSP software by hand or using an autocode tool, etc. Don't know if you are allowed to answer but would be great if you can!
Sure, no really a big secret there:
- Microphone + Listen SoundCheck for measurements
- Octave (free Matlab clone) for modeling and simulation
- PurePath Studio, the DSP software that comes with the TAS3204. Odd
thing is that TI controls access to this software. I don't know why they
don't give it out for free to everybody. The worst that could happen is
that they would sell more parts
By examining the graphs and charts in the paper you can see the signature of
each of these tools.
-Caleb
On Thu, Aug 28, 2008 at 6:55 PM, kmr <
kmr.3evt9z1219975202 (AT) no-mx (DOT) forums.slimdevices.com> wrote:
>
> Being in the control system business (closely related to the signal
> processing field, pun intended), I'm curious about the SW development
> environment for the Boom - what tools were used to design the filters
> and crossovers, were the filters implemented in the DSP software by
> hand or using an autocode tool, etc. Don't know if you are allowed to
> answer but would be great if you can!
>
>
> --
> kmr
> ------------------------------------------------------------------------
> kmr's Profile: http://forums.slimdevices.com/member.php?userid=10664
> View this thread: http://forums.slimdevices.com/showthread.php?t=51599
>
>
This looks like a great product, congratulations to Logitech. One question that wasn't answered in the white paper is in regards to the class D amplifier - what chip is used? How does it compare to other class d, Sonic Impact, Trends, Nuforce Icon, etc.
c
Mark Lanctot
2008-08-29, 06:40
One question that wasn't answered in the white paper is in regards to the class D amplifier - what chip is used?
Actually it was - see the block diagram, figure 1, and the text on page 2. Woofer amp: TI TPA3100D2 (20 W stereo), Tweeter amp: TI TPA3101D2 (10 W stereo). On the block diagram their parts start with "TAS" but these are not on TI's site - the TPA parts are there instead and the text on page 2 indicates "TPA".
How does it compare to other class d, Sonic Impact, Trends, Nuforce Icon, etc.
No clue how they *sound* with respect to these others, but here are the measurement specs:
http://focus.ti.com/docs/prod/folders/print/tpa3100d2.html
http://focus.ti.com/docs/prod/folders/print/tpa3101d2.html
All I can say is that it sounds pretty darn good to me. :-)
Oh and while you're at the TI site, take a look at the DSP:
http://focus.ti.com/docs/prod/folders/print/tas3204.html
A dual-core 48-bit DSP clocked at 135 MHz...I still have a computer slower than that!
dBerriff
2008-08-29, 10:40
Thanks for this white paper. My personal opinion is that it gets its points across brilliantly and gives a great insight into the design targets, principles and compromises. So much so that I cannot see how I am going to resist buying a Boom as your design philosophy sounds spot-on.
As for the tone being informal - so what? It is a model of clarity as far as I am concerned. I just wish my students (and I) could write this well ...
As for the tone being informal - so what? It is a model of clarity as far as I am concerned. I just wish my students (and I) could write this well ...
I wasn't complaining, I find it refreshing to read a white paper that isn't void of all emotion. I was just curious, based on the informality, who it was aimed it.
I wasn't complaining, I find it refreshing to read a white paper that isn't void of all emotion. I was just curious, based on the informality, who it was aimed it.
Me probably , I like Meridian products i have some, the do a lot of DSP speakers with digital crossovers and so. So a product with similar technology at smaller scale intrigues me :)
dBerriff
2008-08-29, 14:46
I wasn't complaining, I find it refreshing to read a white paper that isn't void of all emotion. I was just curious, based on the informality, who it was aimed it.
Sorry, not getting at you. I just wanted to say thanks for such a clearly written and informative white paper.
I would guess it is aimed at the reviewers who, however good a product is, cannot resist telling you how it would have been even better if they had designed it. That is pre-empted here, except for those journalists too lazy to read the white paper.
No clue how they *sound* with respect to these others, but here are the measurement specs:
All I can say is that it sounds pretty darn good to me. :-)
The Squeezebox boom is a product I'd really like to "hear" before purchase, but soon enough I'm sure it will be reviewed/compared...
c
Paul Webster
2008-08-30, 10:36
This might be a silly question - but the paper makes references to 48bit handling - is there some munging going on to handle 44.1KHz source material?
pfarrell
2008-08-30, 10:44
Paul Webster wrote:
> This might be a silly question - but the paper makes references to 48bit
> handling - is there some munging going on to handle 44.1KHz source
> material?
Its 48 bits wide. Not a 48K rate. Not to worry, it does 44.1kHz fine.
--
Pat Farrell
http://www.pfarrell.com/
I enjoyed the white paper. In fact, reading it is what convinced me to order a boom (also the fact that I had been wanting something like this either for our bedroom or wife's study).
Mark Lanctot
2008-09-02, 10:17
The Squeezebox boom is a product I'd really like to "hear" before purchase, but soon enough I'm sure it will be reviewed/compared...
Of course sound is subjective. What a reviewer likes you might hate and vice-versa. But yes, you should always listen to a speaker system yourself using material you're familiar with. That's if you can, of course...
Anyone know where to find the white paper document? Link seems to be dead...
Thx. Jonas
Thanks for this white paper. My personal opinion is that it gets its points across brilliantly and gives a great insight into the design targets, principles and compromises. So much so that I cannot see how I am going to resist buying a Boom as your design philosophy sounds spot-on.
As for the tone being informal - so what? It is a model of clarity as far as I am concerned. I just wish my students (and I) could write this well ...
I felt exactly the same way. It was the first thing I read, and after reading it I knew I had to have one. (Got mine last week).
I have written a bunch of product whitepapers over the years and I know how hard they are to write. I think Caleb did an outstanding job with it. I also applaud Logitech for encouraging content-rich marketing materials. A lot of companies don't do them out of competitive paranoia -- failing to realize that these white papers are the perfect way to market to sophisticated consumers.
BTW, how many engineers do you know who can both design a great product and write as well as this?
muski
pfarrell
2008-09-09, 21:47
muski wrote:
> I have written a bunch of product whitepapers over the years and I know
> how hard they are to write. I think Caleb did an outstanding job with
> it.
Yes, its a great job.
> BTW, how many engineers do you know who can both design a great product
> and write as well as this?
Other than myself, zero. :-)
Most great engineers can't talk, let alone write.
--
Pat Farrell
http://www.pfarrell.com/
Thanks all, but it wasn't that good until it was reviewed by the slim
engineering group, then the forums :-)
On Tue, Sep 9, 2008 at 9:34 PM, muski <
muski.3fi8gb1221021302 (AT) no-mx (DOT) forums.slimdevices.com> wrote:
>
> dBerriff;333882 Wrote:
> > Thanks for this white paper. My personal opinion is that it gets its
> > points across brilliantly and gives a great insight into the design
> > targets, principles and compromises. So much so that I cannot see how I
> > am going to resist buying a Boom as your design philosophy sounds
> > spot-on.
> >
> > As for the tone being informal - so what? It is a model of clarity as
> > far as I am concerned. I just wish my students (and I) could write this
> > well ...
>
> I felt exactly the same way. It was the first thing I read, and after
> reading it I knew I had to have one. (Got mine last week).
>
> I have written a bunch of product whitepapers over the years and I know
> how hard they are to write. I think Caleb did an outstanding job with
> it. I also applaud Logitech for encouraging content-rich marketing
> materials. A lot of companies don't do them out of competitive
> paranoia -- failing to realize that these white papers are the perfect
> way to market to sophisticated consumers.
>
> BTW, how many engineers do you know who can both design a great product
> and write as well as this?
>
> muski
>
>
> --
> muski
>
> Transporter via XLR->Bryston BP26DA->Bryston 4B SST->Wilson Watt Puppy
> 7s
> Transporter via XLR->Headroom Max Balanced Headphone Amp->Balanced
> AKG701s
> ------------------------------------------------------------------------
> muski's Profile: http://forums.slimdevices.com/member.php?userid=3670
> View this thread: http://forums.slimdevices.com/showthread.php?t=51599
>
>
Mark Lanctot
2008-09-10, 06:44
Anyone know where to find the white paper document? Link seems to be dead...
Bump - dxco is right, the white paper seems to be gone.
Other than myself, zero. :-)
Most great engineers can't talk, let alone write.
Now that's something...
Have you ever met any GERMAN engineers? Wonder what phrase you would invent for them.
Whenever I meet American ones I think: "Hey, they know how to present something compared to our guys". Now if that's what you call "can't talk let alone write"...
How's that old joke:
"How do you tell an extrovert engineer from an introvert?"
"An extrovert engineer will look at your shoes when he talks to you."
(Disclaimer: If somebody feels offended, I may say this, technically I AM an engineer...)
pfarrell
2008-09-10, 23:25
pippin wrote:
>> Most great engineers can't talk, let alone write.
>
> Now that's something...
> Have you ever met any GERMAN engineers? Wonder what phrase you would
> invent for them.
Moving wildly off topic, yes. And all of them spoke better English than
my horrible grade school German.
> Whenever I meet American ones I think: "Hey, they know how to present
> something compared to our guys". Now if that's what you call "can't
> talk let alone write"...
> (Disclaimer: If somebody feels offended, I may say this, technically I
> AM an engineer...)
I'm an engineer, four of my brothers are engineers, my father was an
engineer....
Actually, the German engineers were very good when talking about
engineering, and I find that typical. And over a few pils, you can talk
about women, soccer, cars, etc.
Clearly Calib can write, and there are a few others. Too often, good
engineers who can write get promoted to management and then they stop
being engineers.
--
-- toc
toc (AT) curmudgeon4 (DOT) us
http://www.curmudgeon4.us/
Clearly Calib can write, and there are a few others. Too often, good
engineers who can write get promoted to management and then they stop
being engineers.
As long as they understand that, too.
It sometimes helps if management has an understanding of engineering, too.
Bump - dxco is right, the white paper seems to be gone.
Does anyone know how to find the whitepaper?
Sorry for the glitch, the paper (with some minor edits) has been
posted back in the same place.
-dean
On Sep 11, 2008, at 5:12 AM, Sike wrote:
>
> Mark Lanctot;338852 Wrote:
>> Bump - dxco is right, the white paper seems to be gone.
>
> Does anyone know how to find the whitepaper?
>
>
> --
> Sike
> ------------------------------------------------------------------------
> Sike's Profile: http://forums.slimdevices.com/member.php?userid=2458
> View this thread: http://forums.slimdevices.com/showthread.php?t=51599
>
>
max.spicer
2008-09-11, 08:07
Sorry for the glitch, the paper (with some minor edits) has been
posted back in the same place.
-dean
It will be interesting to see the differences between the two versions. ;-)
Max
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