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 #914
Joined: Fri Jul 20 2007, 06:22PM
Location: South Bend, IN
Posts: 85
It would be cool to have a digital version of the old Texas Instruments SN76477 IC. A lot of the old video games used that chip for sound effects.
I've done some experimenting with time-sliced polyphonics, but wave shaping would have to be done by modulating the IGBT input voltage in sync with the gate drive frequency modulation.
Registered Member #103
Joined: Thu Feb 09 2006, 08:16PM
Location: Derby, UK
Posts: 845
That's not just electric guitar, it's lightning guitar! Awesome stuff. Take that to band practice...
So what happens if you strike a harmonic or play a really high note? Just wondering if you have some kind of lowpass filter somewhere between the guitar and whatever generates the interrupter pulses to wipe away the higher frequency parts (and help with emc?)
I'm also going to guess you have some kind of one-shot actually switching the coil on, triggered by a something or other connected to the guitar?!
could you give us any hints on how you built it, if not would a system in witch you use a PWM at extremely low dutycycle and have the set carrier frequency at something like 2-4Khz? would this give an adequate effect on a DRSSTC with low(er) distortion?
Registered Member #30
Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706
Well, I did take it to band practice. :P
My guitar signal processor is based on the work I did for Finn, so I'm still not telling how it works... If you noticed me controlling the size of the discharge with the guitar volume knob in that video, you should have figured it out already.
Banned on 3/17/2009. Registered Member #487
Joined: Sun Jul 09 2006, 01:22AM
Location:
Posts: 617
I have no idea of what he's using.
I think I'm gong to try this using a low pass filter then feeding that into a comparator setup for pwm. Triangle wave will be low frequency like 500Hz. Then maybe have some way to set the max pulse width. Don't know how great it'll sound.
Registered Member #146
Joined: Sun Feb 12 2006, 04:21AM
Location: Austin Tx
Posts: 1055
I think I'm gong to try this using a low pass filter then feeding that into a comparator setup for pwm. Triangle wave will be low frequency like 500Hz. Then maybe have some way to set the max pulse width. Don't know how great it'll sound.
Audio frequency carrier? that would sound absolutely terrible. If nothing else, at least set the PWM to run at 25khz or more. But, considering you only get so many RF cycles inside of 1 period of 25khz you might be limited to about "4 bit" audio.
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.
OMG musical DRSSTC vids
