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Post by 4real on Aug 27, 2008 16:20:01 GMT -5
Actually...I made the title a little vague to allow wider scope should the topic stray about the subject a little. At PG and elsewhere there seems to be a big interest in this feature, but it is not something I had ever really found I "needed" as much as some people appear to...however, I did put one on my new guitar...more on this in a sec... .... Alternate VersionsI did a project recently for someone else that incorporated a couple of "kill switches" that was interesting. I used a large push button to short out the guitar when pressed, and I found a spring return "missle launch switch" large toggle switch to provide a toggle version that would spring back (to on) as a toggle is the preferred method for this player. Being the kind not to leave well enough alone and the person wanting something "different" in this guitar I rewired the inside of the toggle so it was both normally off and normally on and added a push pull pot, very small cap and trim pot and adjusted it like a tone control... The end result was that I think I invented a "maim" control ;D! It wont kill the guitar but it will seriously damage the tone. Actually, the toggle switches between on and an exaggerated full tone off making a kind of mmmwwhaaa, mmmwwwhhaaa kind of effect. .... So...with all this interest and because I found an interesting switch to try, I fitted one to my new telecaster...   Under normal light (top) it is virtually invisible, but with the flash, you can see it. This is a surface mount type switch that works either as normally on or off depending on the wiring and is a momentary dpst switch and seems quite hardy. I glued it to a bit of MDF spacer board that also holds the LED (for the sustainer on indicator) and the volume control mounts through the spacer board holding it all on there... who's a clever boy then  .... Ok...here is a problem to put your minds to...#1 ... there is a slight clicking when used clean. Probably it is there when distorted but you don't notice it  . #2 ... when used, the output is shorted (hot to ground where the output leaves the volume control). Killing the sound also kills the sound to the sustainer circuit so it looses drive while stuttering away... It would be cool if the guitar would sustain away for as long as you like and you could tap out rhythms on it. Interestingly, the circuit will sustain away with the volume control on zero. .... Enable SwitchIn use the 'kill switch' does take a bit of getting used to, with this kind of thing, you are actually tapping out the spaces which is a little "anti-intuitive". It was pointed out to me that what you really want is an "enable" switch. Perhaps that is why some favor the toggle thing as you can have it so when you move it you actually get sound instead of killing it... (like Townsend used to do with his Les Pauls by turning the volume down on the neck pickup and switching between pickups with the selector). .... I was wondering if you guys had any suggestions about #1 & 2...perhaps a resistor or something was what I was thinking... And... other ideas in general for different "kill switch" variations. One I thought of for instance was an enable switch when the guitars volume was turned down...this could give a kind of manual tremolo effect perhaps...maybe not useful  .... Kill Switch GeneralitiesFor some reason GN2 seems to have been somewhat immune to the Kill Switch phenomenon, I still haven't found a reason to use it so much but there have been a few moments where it would be fun. If I could get it to work with the sustainer a little better, this could produce some very interesting effects...I dare say you could get some robotic taking like effects with a wha wha for instance or some synth sequencer type of things too. .... Anyway...thought you guys might need a distraction and this may be of interest, plus I might solve my "problems" (if only that were true!) without stretching my mind...plus, I dare say some interesting discussion may ensue (or not). I'd be interested to here if people have an explanation for the driver of the kill switch popularity and examples of how it can be used creatively. I believe "buckethead" has a guitar hero track that features it, and tom morello fromm RATM apparently uses it for Hip/hop like scratching effects. pete |
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Post by ChrisK on Aug 27, 2008 16:40:13 GMT -5
Hmmm, that might just be because those that have the awareness of and the desire to seek out more/different/better tone from enhanced (re)wiring have possibly evolved/matured beyond the fascination with mere binary tone controls. After all, there are two kinds of people in the world; . . . . . . . . . . . . those that think that there are two kinds of people in the world and those that don't. Ha! You thought that I was going to say " understand binary".  |
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Post by 4real on Aug 27, 2008 17:44:55 GMT -5
Touche ;D
No doubt this explains the 47 karma points...hahahaha...opps
The Kill Switch is a bit of a cheap trick I know...the "binary tone" a slightly up/low market variation for sure.
Any thoughts however on the "clicking" thing or the sustainer thing? I don't think it is a factor of the switch quality or if this is a common thing with this kind of device!
pete
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Post by ChrisK on Aug 27, 2008 18:34:29 GMT -5
Does it click when the sound is first shorted to ground or when it is first turned back on? If the former, the AC waveform output will have some DC ending point (a function of the instantaneous clamping of the signal from instantaneous value of the AC waveform at the moment of switch opening to the ground potential). This fast voltage change will have some possibly significant high frequency content. If the latter, the AC waveform output will have some DC starting point (a function of the instantaneous elevation of the signal from ground potential to the instantaneous value of the AC waveform at the moment of switch opening). This fast voltage change will have some possibly significant high frequency content. And 5ifth ( ;D ;D), mechanical switch contacts bounce! Na-na-na-na-na, ta-ta-ta-ta-ta.......oh-no-no-no-no-no.... So you'll get several "instantaneous elevations and shortings" for free. Some folk might characterize this effect as a "clicking" sound? You can solve this by limiting the high frequencies passed by the use of a low pass filter. Unfortunately, since filters are fairly stupid, they tend to limit ALL high frequencies, including those that we want to keep. I think that you need to investigate this maiming effect (please consider some focused psycho-therapy as well) and tone it down to an "Oooh-Ahhh" level. Hmmm, "maim", "kill", "seriously damage", "mmmwwhaaa, mmmwwwhhaaa".  Where are you located again? |
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Post by andy on Aug 27, 2008 19:43:59 GMT -5
I believe "buckethead" has a guitar hero track that features it, and tom morello fromm RATM apparently uses it for Hip/hop like scratching effects. I've not been very impressed by stuff I've heard by Buckethead on the whole, but I saw a very good video of him using a kill switch to play a song, with a 'tapped' riff going on with the left hand and the right hand on the switch. I'm sure it was Youtube, so if I can find it, I'll post a link. If I don't either assume it is no longer there, or I found it and it is not as exiting as I remember! I can't be any technical help on this however.  |
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Post by andy on Aug 27, 2008 19:55:24 GMT -5
Ha, that was easy- I was expecting a real hunt. It seems this is quite a popular track as there are plenty of videos of the song up- this one is the one I first watched though, I think. I've only checked the beginning, but it has some pretty good switchery going on, with that tapped thing and a whammy pedal too.  |
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Post by 4real on Aug 27, 2008 22:00:32 GMT -5
At the beginning...tick like click... Ummm...if no sound is playing but guitar on, pushing the switch makes no noise, click volume depends on amount of sound coming out of the guitar (not amp volume) and is quieter than the signal (so is probably lost behind distortion). hahaha...well it wasn't my guitar, but the person I did it for is pretty keen...I will have news on this guitar project in the near future...shhhh Of course, down here I was able to use the vernacular to better describe what it does to the tone... ;D .... but since this is a family friendly forum... I will be receiving therapy....it may well involve putting on a mask, wig and bucket...(that's right...I said buck et...not what the maim switch does to the guitar tone, which is technically two words anyway...like bi nary. Hopefully I will recover... Speaking of which... Thanks andy, yes I have seen this one before and apparently this of all guitar songs has made Guitar Hero...of all the !&#%!?!...still, with GH you are only tapping away at buttons so I guess it is appropriate! EDIT...aaah...here is the tom morello dj like use of the thing... Even more interesting...the GH version... Extensive use of the wammi pedal there...it seems to work a bit better than the bucket man...I think I am strating to understand what is driving the kill switch option...its GH3! ..... Back to the topic...so I was wondering if instead of a straight short to ground if a resistor might help so it isn't going to a complete short...clutching at straws really. Maybe a 1M across the switch points or something? There doesn't seem to be a bounce problem...after all you have your finger on the button... As an extra bonus...with the sustainer on, that blue LED lights the finger doing the tapping turning it blue and effectively flashing as you do it... Which reminds me...there is a battery in there for the sustainer but it is not connected when off and the symptoms are the same when on...so I don't think this is the issue either. So...this seems to be the problem...got any suggestions for a solution or do all these things make little clicking sounds when used. I believe that Tom Morello has a more convincing use of the kill switch thing. I put it on there because I could and thought I might as well investigate it since there seems to be so much interest. There have been a few subtle little places that I think it can be used to reasonable effect...no a must have by any means however. I can see some potential for some cool effects with the sustainer if the strings could continue to be driven even with the guitar signal "killed". A filter or flanger sweep, or wha can produce some interesting 'baba o'reilly'/'won't get fooled again' like early synth sounds...even on it's own, the sustainer can morph between fundumental and harmonics and these little bites can give an interesting effect. Anyway...thanks for the consideration....any further suggestions most welcome and appreciated. pete |
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Post by ashcatlt on Aug 27, 2008 22:47:39 GMT -5
I'm thinking that #1 and #2 are related. #2 freaks me out, considering that the switch should be doing exactly the same thing as the volume pot, and the sustainer circuit would be expected to respond the same to both. Where's the schematic for this guitar? One use I've found for my kill switch is to shut the guitar off between songs. Mine's not spring loaded (being a standard strat 5-way), and it's a lot easier to flip that switch than to turn all three pickup switches. Especially since I always forget which way is off on those rotaries... |
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Post by 4real on Aug 28, 2008 3:59:19 GMT -5
It is a little freaky isn't it...
I am not sure what is going on and I better check things a little more...but the guitar plays itself even with the volume down so you can do volume swells wit it for instance.
I don't have a schematic as such (I may draw one) but basically the bridge pickup connects directly to the circuit and the selector. When switched on, the neck pickup is bypassed and the bridge pickup goes directly to the volume control and then out. -v9 is connected to the ground and the input to the circuit is bridged between ground and hot signal by a 1Meg resistor.
Why it works with the volume down I don't know...this should be close to a short at zero right? So...why any different with an actual short.
Similarly...this made me wonder about the click. If it were a power thing, you would think it would click even if there were no sound out of the guitar but still active. Conversely, you would think that there would be a difference if only using the neck pickup perhaps where the hot of the circuit and bridge pickup is lifted...very odd.
So...yes, it may well be related. Hence I was wondering if adding some kind of resistor load or smoothing cap would somehow help with this fairly small noise an an otherwise exceptionally quiet guitar (both pickups are HB's of a sort).
I used to use the "kill" abilities of the les paul a lot as I used to do the intros and such between songs and you know...gesticulate at the beer throwers (it was the punk era and there were no stages as such so it did get a little vulnerable at times...I almost lost my teeth on one occasion when a drunk fell over and knocked the mic stand...mid song...I still feel the pain!)...obviously a nice heavy guitar like an LP makes for an intimidating weapon.
pete
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Post by andy on Aug 28, 2008 6:42:36 GMT -5
Even more interesting...the GH version... Mmmmmmeh... I think I'll vote for the first one as the more interesting! If my guitar ever catches fire like that on GH though, I'll be straight down here to isolate my wiring problem! |
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Post by ChrisK on Aug 28, 2008 17:44:10 GMT -5
Yep'ski. If there is no signal coming out of the guitar when the switch is switched between shorting or not, there is no difference in the DC/instantaneous signal and a click is not possible. The instantaneous DC value of the signal is similar to the the sine(x) value of a sine wave (or cosine, depending on where one starts - same is). While there are harmonics involved, the concept/problem is still the same. For any given signal output other than zero RMS (Root Mean Squared - a statistics term applied to AC circuit theory), at any given instant other than at the instant of a zero VDC cross, there will be an instantaneous change in this DC level, which is only the entry or exit point (start/stop) of the AC signal. If you evaluate a sine wave using the differential calculus, you will find that its derivative is a cosine. In other words, it only contains one pure frequency. However if you switch this signal instantaneously on, the derivative of the near vertical slope is a nearly infinite (well, limited by the cable yada-yada...) impulse step function. This contains serious, but brief high frequency components. You know, in a clicky sort of way. If you can limit the rise/fall time, you can limit the high frequency content. And yes, ALL mechanical switches bounce (well, except for the illegal mercury wetted contact ones - try to get that passed RoHS). The bounce rate is in a few milliseconds, right in the range of 300Hz to 1Khz (hmmm, THE range of interest to guitarists). The proper solution is to use a series RC filter of empirical (your homework) component values. This is called a snubber circuit. If you don't want this snubber to continuously affect the tone, try using a sequential three position toggle switch (the ubiquitous DP3T ON-ON-ON). Up is out, middle is snubber in to ground, lower is signal short to ground (make sure that the snubber is also shorted across the RC circuit to ensure an equal snubbing action on turn-on). |
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Post by 4real on Aug 28, 2008 20:43:16 GMT -5
ekkkk...you lostme at "calculus"
"empirical"....so you want me to invade and take over another country...hmmm...or start a revolution and oust the queen of Oz?!
RC Filter...I'm guessing that doesn't stand for "children's radio"...
"snubber", that can't be right, that's where you get no answer to a post....hmmm
....
I know...you are suggesting effectively a tone control type circuit/filter...resistor and cap of a value that will suppress the click...is that it?
Well, I definitely wont be adding any switches to this...so perhaps I will just need to find a value that least affects the guitar's tone...
Is there an "improper way?
I was thinking originally that the solution may be to use a resistor so that it is switching between almost off and full on...that kind of thing.
The guitar is bright enough to allow for a little tone and volume roll off, Is this clicking then to be expected on any "kill switch"
Another approach would be to lift the signal instead of shorting it out...would this have the same symptom or introduce excessive noise. Such a solution is possible with this switch. It would also solve #2 in that the sustainer circuit would still be connected and run even when the guitar's signal is "dead"?
....
Next time I have the soldering iron out, I will try a few "experiments"...
thanks again...
pete
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Post by ChrisK on Aug 28, 2008 21:13:31 GMT -5
Sorry, if one truly wants to 'see' how things really work, one has to really learn and 'see' the calculus (only the truly pompA$$ actually call it 'the calculus'). Yeah, a Snubber. Try it. Try opening the signal chain before the volume pot (or wherever it makes 'sustaining' sense). It doesn't hurt to have a 1 MOhm or so resistor when the signal is not driving the cable (why I suggested before the volume pot/free pull-down resistance at the cable). Its Resistance will form an RC filter with the cable Capacitance and not excessively load down the pickups. |
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