| Andrew Cooke | Contents | Latest | RSS | Twitter | Previous | Next

C[omp]ute

Welcome to my blog, which was once a mailing list of the same name and is still generated by mail. Please reply via the "comment" links.

Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

Personal Projects

Lepl parser for Python.

Colorless Green.

Photography around Santiago.

SVG experiment.

Professional Portfolio

Calibration of seismometers.

Data access via web services.

Cache rewrite.

Extending OpenSSH.

C-ORM: docs, API.

Last 100 entries

Calling C From Fortran 95; Bjork DJ Set; Z3 Example With Python; Week 1; Useful Guide To Starting With IJulia; UK Election + Media; Review: Reinventing Organizations; Inline Assembly With Julia / LLVM; Against the definition of types; Dumb Crypto Paper; The Search For Quasi-Periodicity...; Is There An Alternative To Processing?; CARDIAC (CARDboard Illustrative Aid to Computation); The Bolivian Case Against Chile At The Hague; Clear, Cogent Economic Arguments For Immigration; A Program To Say If I Am Working; Decent Cards For Ill People; New Photo; Luksic And Barrick Gold; President Bachelet's Speech; Baltimore Primer; libxml2 Parsing Stream; configure.ac Recipe For Library Path; The Davalos Affair For Idiots; Not The Onion: Google Fireside Chat w Kissinger; Bicycle Wheels, Inertia, and Energy; Another Tax Fraud; Google's Borg; A Verion That Redirects To Local HTTP Server; Spanish Accents For Idiots; Aluminium Cans; Advice on Spray Painting; Female View of Online Chat From a Male; UX Reading List; S4 Subgroups - Geometric Interpretation; Fucking Email; The SQM Affair For Idiots; Using Kolmogorov Complexity; Oblique Strategies in bash; Curses Tools; Markov Chain Monte Carlo Without all the Bullshit; Email Para Matias Godoy Mercado; The Penta Affair For Idiots; Example Code To Create numpy Array in C; Good Article on Bias in Graphic Design (NYTimes); Do You Backup github?; Data Mining Books; SimpleDateFormat should be synchronized; British Words; Chinese Govt Intercepts External Web To DDOS github; Numbering Permutations; Teenage Engineering - Low Price Synths; GCHQ Can Do Whatever It Wants; Dublinesque; A Cryptographic SAT Solver; Security Challenges; Word Lists for Crosswords; 3D Printing and Speaker Design; Searchable Snowden Archive; XCode Backdoored; Derived Apps Have Malware (CIA); Rowhammer - Hacking Software Via Hardware (DRAM) Bugs; Immutable SQL Database (Kinda); Tor GPS Tracker; That PyCon Dongle Mess...; ASCII Fluid Dynamics; Brandalism; Table of Shifter, Cassette and Derailleur Compatability; Lenovo Demonstrates How Bad HTTPS Is; Telegraph Owned by HSBC; Smaptop - Sunrise (Music); Equation Group (NSA); UK Torture in NI; And - A Natural Extension To Regexps; This Is The Future Of Religion; The Shazam (Music Matching) Algorithm; Tributes To Lesbian Community From AIDS Survivors; Nice Rust Summary; List of Good Fiction Books; Constructing JSON From Postgres (Part 2); Constructing JSON From Postgres (Part 1); Postgres in Docker; Why Poor Places Are More Diverse; Smart Writing on Graceland; Satire in France; Free Speech in France; MTB Cornering - Where Should We Point Our Thrusters?; Secure Secure Shell; Java Generics over Primitives; 2014 (Charlie Brooker); How I am 7; Neural Nets Applied to Go; Programming, Business, Social Contracts; Distributed Systems for Fun and Profit; XML and Scheme; Internet Radio Stations (Curated List); Solid Data About Placebos; Half of Americans Think Climate Change Is a Sign of the Apocalypse; Saturday Surf Sessions With Juvenile Delinquents; Ssh, tty, stdout and stderr; Feathers falling in a vacuum; Santiago 30m Bike Route

© 2006-2015 Andrew Cooke (site) / post authors (content).

NXT (Distributed Mode) Speakers

From: "andrew cooke" <andrew@...>

Date: Mon, 19 Jun 2006 18:29:28 -0400 (CLT)

Just noticed these.  http://www.elac.com/en/products/imago/dml.html has a
description and images.

My first reaction was - that must sound terrible!  How can you get good
stereo imaging if the phase information at high frequencies is lost?  For
years people have been trying to build extremely rigid speaker cones to
avoid the kind of behaviour that is a "feature" here; the only advantage
seems to be wide dispersion.

But then I thought - maybe there's something really cool happening here. 
Some kind of mix between chaotic motion and synthetic apertures.  It
seemed crazy, but then some highish-end audio companies seemed to be using
the technology.  So I poked around some more.

The technologoy is patented (how can you patent a bad speaker?) by NXT -
http://www.nxtsound.com/index.php?id=476&no_cache=1

It was difficult to find neutral opinions.  Since the technology enables
thin flat and curved panels it is very "marketable".   It's difficult to
separate marketng blurb from "this really sounds good".

Eventually I found this review -
http://www.findarticles.com/p/articles/mi_zdext/is_200308/ai_ziff46255/print
- for computer speakers.  You wouldn't expect that to be a very demanding
application, but the review was surprisingly negative.

Next, a HIFI Choice review of Mission speakers.  Two reviews, in fact. 
Their site is dead, but Google has caches if you click through the first
two hits for http://www.google.cl/search?q=hifi.choice+mission+NXT  Both
reviews are negative.

Finally, here's a detailed argument on ribbon speakers -
http://www.svconline.com/mag/avinstall_turning_pro/index.html - which
says:

Electrostatics and planar magnetics (ribbons) are driven uniformly over
their entire diaphragms. This is the exact opposite to the distributed
mode ideal of flat NXT panels, which operate in random phase across their
surface. Cones, on the other hand, are uniform (pistonlike) up to the
midrange. It is generally conceded that ribbons and electrostatic panels
tend to sound better than cones, while the distributed mode panels sound
worse. However, in certain pro applications in which a uniform phase line
array's excellent pattern control is not needed, the nature of NXT panel
radiation (the “antiribbon”) is an advantage. The wide coverage and random
phase of a well-executed NXT design, such as the Armstrong i-Ceilings
panel, is an advantage in the struggle to achieve wide uniform coverage
with low ceilings as well as high acoustic levels before feedback. The
random phase nature of the panel helps prevent feedback, effectively
randomizing the phase of the signal. The Armstrong panels actually sound
quite decent, to boot.

So, no cool chaotic synthetic aperture...

Andrew

Comment on this post