On Mon, 2010-07-19 at 20:17 +0100, Folderol wrote: > On Mon, 19 Jul 2010 14:04:24 +0200 > Ralf Mardorf <[email protected]> wrote: > > > On Mon, 2010-07-19 at 01:30 -0400, Tim E. Real wrote: > > > On July 18, 2010 03:57:06 pm Ralf Mardorf wrote: > > > > A lot of kids wish to have a kill switch for their guitars. > > > > A kill switch is a short circuit, to 'stop' the audio signal. > > > > > > > > I'm not fine with this solution, but the kids argue, that e.g. an > > > > interruption does cause unwanted noise, especially for over drive > > > > sounds. IMO even using opto-electronics won't solve the issue, because > > > > the noise of the transistor overdrive effect still would be hearable, > > > > while for a short circuit there is silence. > > > > > > > > Has anybody an idea to solve this without a short circuit? > > > > > > > > I'm really not a fan of short circuits. Note, it's not possible to do an > > > > interrupt all the times behind the latest noise generator and even an > > > > interrupt could cause noise itself, while a short circuit indeed is a > > > > good way to cancel sound. > > > > > > > > > > If you play a Gibson you can set the neck pickup volume to zero and > > > the bridge pickup volume to full and then toggle the pickup switch, > > > rapidly if desired, like Eddie van Halen on You Really Got Me. > > > Tim. > > > > Yes, but this could cause noise by the switch or by effects, e.g. the > > sustainer. I guess the kids prevent any noise by a short circuit, > > perhaps even the sustainer then will be 'killed', if so, OTOH I guess > > this won't be good for the effects and amps. As some people mentioned > > before, it would be better to use some kind of gate at the end of the > > effect chain. I really wonder what happens to e.g. a sustainer or to the > > pre-amp of the guitar's amp when doing a short circuit. I guess because > > of a short circuit there really will be silence. I also wonder if just > > interrupting would cause that annoying noise, believing the hype, it > > should cause annoying noise. Btw. for all this Japan avant-garde a > > Gibson switch or a foot switch isn't good, they do need a momentary > > switch. Because it's really used by kids, I wonder how old the equipment > > would become. A short-circuit protection won't protect against impulses, > > OTOH just interrupting might also cause impulses. > > > > Thank you all :) > > > > Ralf > > I'm not really clear on what your objection is to shorting the guitar > pickups. I've never heard of it causing any problem. > > There is a remarkably effective click-free way of muting a guitar. The > original involved a light-dependent-resistor and a filament bulb, but > these days you'd be better off using an LED as the light source. > > The L.D.R. (typically ORP12) is in a light proof box with a > hole in line with the LED. The LDR shunts the guitar output. When > 'dark' it has a typical value of 5 Meg, and has no noticeable effect. > When 'light' it is typically 100 Ohm and effectively shorts out the > pickups. > > However the trick is NOT to switch the LED off and on, but to keep it > on all the time and arrange the pedal/switch so it slides an opaque > vane or shutter between the LED and the L.D.R. > > These switches can be made *extremely* robust and never wear out or > become noisy. > > A variant of this was used as a swell pedal in the original GEM portable > organ of the middle 1960s - I know. I had one :)
I never opened a Morley pedal, but I guess this is the way they use opto. But it's solved, I did error in reasoning: -------- Forwarded Message -------- From: Gordon JC Pearce <[email protected]> To: [email protected] Subject: Re: [LAD] May I asked something OT? Date: Mon, 19 Jul 2010 20:04:28 +0100 On Mon, 2010-07-19 at 14:45 +0200, Ralf Mardorf wrote: > http://www.instructables.com/image/FC6ZZ0XF8JUW8E8/What-is-a-killswitch.jpg > > This is what I call short circuit. It won't harm a pre-amp doing it by a > potentiometer, but I wonder if doing it fast, again and again by a > switch won't cause impulses, when the short circuit will be released > again? Perhaps I do error in reasoning and it's quite save. Yes, it's entirely safe. At that stage you've got a few tens of millivolts of signal at best, across about a 1k impedance source. Gordon MM0YEQ _______________________________________________ Linux-audio-dev mailing list [email protected] http://lists.linuxaudio.org/listinfo/linux-audio-dev
