If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
Donate:
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.
Special Thanks To:
Aaron Holmes
Aaron Wheeler
Adam Horden
Alan Scrimgeour
Andre
Andrew Haynes
Anonymous000
asabase
Austin Weil
barney
Barry
Bert Hickman
Bill Kukowski
Blitzorn
Brandon Paradelas
Bruce Bowling
BubeeMike
Byong Park
Cesiumsponge
Chris F.
Chris Hooper
Corey Worthington
Derek Woodroffe
Dalus
Dan Strother
Daniel Davis
Daniel Uhrenholt
datasheetarchive
Dave Billington
Dave Marshall
David F.
Dennis Rogers
drelectrix
Dr. John Gudenas
Dr. Spark
E.TexasTesla
eastvoltresearch
Eirik Taylor
Erik Dyakov
Erlend^SE
Finn Hammer
Firebug24k
GalliumMan
Gary Peterson
George Slade
GhostNull
Gordon Mcknight
Graham Armitage
Grant
GreySoul
Henry H
IamSmooth
In memory of Leo Powning
Jacob Cash
James Howells
James Pawson
Jeff Greenfield
Jeff Thomas
Jesse Frost
Jim Mitchell
jlr134
Joe Mastroianni
John Forcina
John Oberg
John Willcutt
Jon Newcomb
klugesmith
Leslie Wright
Lutz Hoffman
Mads Barnkob
Martin King
Mats Karlsson
Matt Gibson
Matthew Guidry
mbd
Michael D'Angelo
Mikkel
mileswaldron
mister_rf
Neil Foster
Nick de Smith
Nick Soroka
nicklenorp
Nik
Norman Stanley
Patrick Coleman
Paul Brodie
Paul Jordan
Paul Montgomery
Ped
Peter Krogen
Peter Terren
PhilGood
Richard Feldman
Robert Bush
Royce Bailey
Scott Fusare
Scott Newman
smiffy
Stella
Steven Busic
Steve Conner
Steve Jones
Steve Ward
Sulaiman
Thomas Coyle
Thomas A. Wallace
Thomas W
Timo
Torch
Ulf Jonsson
vasil
Vaxian
vladi mazzilli
wastehl
Weston
William Kim
William N.
William Stehl
Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
Registered Member #1278
Joined: Thu Jan 31 2008, 10:34PM
Location:
Posts: 2
I always thought that a acual sonic grenade would be cool to add to my collection of neat stuff. It would just be able to shatter glass like a opera singer when they hit the right note. So why not in something you could activate in a small box? The thing is, I have absolutly no idea where to start with a device like this. I don't even know if such a thing is possible in a basement-stlye setting like mine. This is therorectical stuff, I just think that being able to shatter in a small area-of-effect stlye setting [and without breaking eardrums]
Registered Member #27
Joined: Fri Feb 03 2006, 02:20AM
Location: Hyperborea
Posts: 2058
A device that makes loud sounds is not difficult to make. Shattering glass with sound is not possible except in special unrealistic cases.
It is possible to get drinking glasses that have very high tensions because they are not made correctly. Those can some times be broken by a human voice or a powerful speaker. Any other type will not break at any sound level you can create in your basement.
Registered Member #27
Joined: Fri Feb 03 2006, 02:20AM
Location: Hyperborea
Posts: 2058
As I said it does not work in general cases, just in special cases with special glass and with special "speakers". If you look at the small opening of the speaker and the short distance to the glass you will get some clues.
Such setups are not realistic and not even interesting. It is rigging an experiment to give the impression of a certian result by carefully not explaining what really goes on. As those experiments are presented in 99% of the cases it is based on pseudoscience because they pretend to do something that they don't really do.
By using an average strength drinking glass (or far below average) and subjecting it to an even sound field in stead of puffing air at a specific location on a glass the wole studio would have fallen down before anything interesting happened to the glass.
Registered Member #1262
Joined: Fri Jan 25 2008, 05:22AM
Location: Maryland, USA
Posts: 451
Mythbusters did a couple experiments related to sound destroying stuff; in one they managed to break a wine glass using an un-amplified voice (although they said it likely had a structural flaw) and in another they built a huge speaker cone powered by a diesel engine that failed to destroy the car it was housed in with sound alone. In yet another episode they put out a flame by playing low frequencies with very high amplitude (like 155db). It is possible to destroy stuff with sound but but not remotely practical.
Registered Member #190
Joined: Fri Feb 17 2006, 12:00AM
Location:
Posts: 1567
I saw the mythbusters with the car. They wanted to see if a "supp'd up" system could blow out the car's windows. The problem was that as soon as a vent was created, such as blowing a small opening in the sunroof, the pressure was relieved. The sunroof was blown off, and then the "woofer" self-destructed.
Registered Member #1025
Joined: Sun Sept 23 2007, 07:53PM
Location: Czech Rep.
Posts: 566
Bjørn Bæverfjord wrote ...
As I said it does not work in general cases, just in special cases with special glass and with special "speakers". If you look at the small opening of the speaker and the short distance to the glass you will get some clues.
Such setups are not realistic and not even interesting. It is rigging an experiment to give the impression of a certian result by carefully not explaining what really goes on. As those experiments are presented in 99% of the cases it is based on pseudoscience because they pretend to do something that they don't really do.
By using an average strength drinking glass (or far below average) and subjecting it to an even sound field in stead of puffing air at a specific location on a glass the wole studio would have fallen down before anything interesting happened to the glass.
I wouldn’t be so resolute that destroying glass without flaw by sound is not possible. Resonant transfer of energy has no real limits. The limiting factor is the power of the source and how good is the resonance. Theoretically you can deliver enough energy to the glass not only to break it but also to melt it. The practical thing is of course not so trivial. Best way of thinking about resonance for me is to imagine kids on a flip-flop device. By sending pulses to the flip-flop of certain stable frequency you can match basic resonance and keep the flip-flop running. In case you want to break the joints apart and fly away with whole flip-flop “cabin†you need a very strong kid and more importantly you need a specific pulse rate to achieve it. Experienced kids know when to send the pulse because their senses give them quick feedback and their muscles response and modulate the frequency of the pulses, luckilly the energy losses of the flip-flop device and low strenght of the kids are great limitting factor for the fly away scenario
It seems to me the same with the unbreakable drinking glass. It is not enough just sending constant sound pulses – you need to modulate the pulses according to the glass (flip-flop) vibrating response. This could be achieved by some crazy mathematical calculations and good signal generator able to reproduce these calculations. Or alternatively to solve some kind of feedback system (maybe a laser based detector) modulating the frequency in real time. But it should be possible – actually nice challenge don’t you think so?
Registered Member #567
Joined: Tue Mar 06 2007, 10:55AM
Location: Singapore
Posts: 147
Heck, if you could actually implement a laser bounce feedback, you could probably use a basic PLL SSTC circuit with some minor changes to driver a speaker.
Registered Member #1025
Joined: Sun Sept 23 2007, 07:53PM
Location: Czech Rep.
Posts: 566
Firnagzen wrote ...
Heck, if you could actually implement a laser bounce feedback, you could probably use a basic PLL SSTC circuit with some minor changes to driver a speaker.
The speculative laser feedback could be based on known spy device. I’ve never seen the device (and maybe it is a hoax) but I red it is commonly used for detecting peoples voices by scanning the car’s or room’s windows. Sound vibrations are detected on the glass surface by a laser beam. Hell, I have no idea how this is achieved (some kind of reflections, Doppler effect?). Maybe someone knows more?
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.
Sonic grenade
