bluesy

Only if you don't trust the mathematics. A time constant is just that, constant, doesn't matter how frequently you try to fill or empty it. Another way to look at it is that as frequency goes up, the impedance of the capacitor (ac resistance if you like) goes down. So as frequency get's really high, the capacitor starts to look like a short circuit, and since it's shunts the ac to ground, the high frequencies don't get through. Hence it's a low pass filter.

I just reread it and I think he said he set the intonation on the 12th fret, but on one string only, it's sharp on the 3rd fret. Sorry... The fretted "G" is out but the other frets are out too. 1st fret to 5th fret are the worst ... so its not JUST the 3rd fret. Strings are older so that could be it too. Yeah, that's right, but the important bit is that the other strings are OK and this hasn't just started happening on a guitar that was working fine originally.

Yes, to remove lows, essentially a series cap is used - google "high pass" filter. Not sure what you mean in that last paragraph. A volume control is a potential divider, i.e. a device that takes an input voltage (signal in this case) and provides, as it's output, some fraction of that signal. When a pot is at 10, it is not supposed to have an effect on the signal, because you have asked for 100% of the signal to be let through.

That page is about DSP filters and is looking at recursive filters. Also cascading 2 single pole filters gives you a 2 pole filter, so the slope is doubled to 12db per octave. I was only saying that there was no need to have multiple caps for a tone switching circuit to allow you to achieve all the desired cutoff frequencies (with single pole low pass filters), just vary the resistance. The analogy demonstrates the time constant of the RC circuit, and that is exactly what determines the cutoff frequency, so yes, it does apply to AC.

I just reread it and I think he said he set the intonation on the 12th fret, but on one string only, it's sharp on the 3rd fret.

Me again yes it would act pretty much the same as a cap shunt to ground. It's another way to make a single pole low pass filter. It's not usually done this way in production because caps are cheaper and lighter than inductors.

The 6db figure can be calculated, but check any text or online reference for any single pole filter. Sometimes it is expressed in decades (I think it's 20db per decade). How about an analogy? The capacitor is a bucket, and the resistor is a faucet restricting the flow of water (electricity). For a given size bucket, and faucet setting it will take X seconds to fill the bucket. Now get a bucket (capacitor) twice as big, and halve the restriction (resistor) - meaning the flowrate will be doubled. The bucket still takes the same X seconds to fill.

I like that idea. I will try it myself. Although, this whole compromise tuning thing has just given me something to obsess about all the time. I need to clear my head and just play some music instead of worrying about inadequacies of the instrument's tuning and the equal tempered scale. I constantly hear 3rds that aren't so sweet anymore and have grown to hate that open C chord

My theory If the string is not sitting properly in the nut slot, e.g. if it's last point of contact is not right at the bridge side of the nut, then this can happen. When this happens, the first fret is effectively too long. Let's say the string is actually only touching the nut at the headstock edge, the first fret is effectively increased by the width of the nut material, hence all notes will be sharp compared to the open string, and it will be more noticeable on the low frets. Also, too high an action, means the string stretches when you fret it, and this also sharpens the note.

what does "F" mean? frequency? frequency of what? i'm pretty sure that halving the resistance and doubling the capacitance don't give you the same frequency response curve. maybe at one specific frequency it's the same, but not the whole curve. We are talking about the various frequencies found in what you call a guitar's sound. F in the formula is the frequency at which the filter starts to work. It is defined as the point where the signal is attenuated 3 dB, or 70.7%(the "half power point indicated below). Higher frequencies are attenuated at 6db per octave, lower ones are left mostly alone. The slope is fixed because it is only a single pole filter, so if the frequency that you calculate is the same, the response must be the same. Note that the formula given in the graph is the same as the one I gave, because w = 2*pi*F

Thats a great point J and it also makes it much more apparent to whether or not your saw is up to the task and how suited the blade is as well. If the only way you can get a cut is by force then something is wrong. I think the oscillating feature on jigsaws now will go a long way to increase the saws ability, especially for things like rough cutting a blank and the like. Yes it certainly does. The oscillating makes it much easier to cut, BUT, turn it off when you are trying to navigate any tight curves, as it effectively makes the blade very wide, and therefore, hard to turn.

This is so similar to one I built. I built mine into a Washburn cab and chassis in which someone had turned the power module into a blob of melted silicon. I presume from the tube lineup it's pretty much like a Fender Champ. That's what mine is. Like you I always build my amps point to point wired. I used a real Fender output transformer in mine - 'cos I got it cheap. Anyone thinking of buying Daniel's, I can say that I think a small tube amp like this makes the best practice amp you can get.

Some people do, but I avoid it because I figure the pressure from all those tight fitting frets might cause the wood to bow, and so be hard to glue to the neck. The other reason is that I glue the fingerboard onto the neck, then use a flush trim router bit to shape the fingerboard edge perfectly to the neck shape - and you can't do that with frets in

I agree, but relying on mechanical, rather than soldered connections SOMETIMES causes problems. You could run a ground wire from the switch metalwork to the common grounding point, but route the wire physically close to the metalwork. This reduces the area of any hum loop that may be formed. This also applies to the black wires you have joining the pots together. Push them down to run along against the metal shielding.

What's wrong with 90 degrees? http://www.cs.dartmouth.edu/~wbc/new/sender.jpg

Interesting, but I wonder if the speed of sound is the reason. Speed does not equal frequency. The speed of sound is the speed with which a sound propogates through the air - e.g. the delay in hearing a thunderclap. However, if the resonant frequency of a metal string changes with temperature, then we are onto something Actually, it has to change, because metal contracts with cold, and that puts more tension on the string. The question is if it is enough to change the tuning significantly.

I can't access that picture from here, but I would say that if string tension will keep the tuner in the correct position, I'd put a little wood filler in and sand it flat. If string tension will pull it away from the desired position, maybe something a bit stronger, like some wood shaped to fill the gap?

Great tutorial. That one sentence above would have saved me some grief when I was starting out I worked it out by trial and error myself - eventually I would just like to add that I don't "go all the way" to achieve the absolute best. I usually end up with a touch more relief than optimal, but that suits me because I do most of my heavy strummin' using chords in the low fret region (below the 10 to 12th fret) because I don't like the sound of bar chords any higher than that. I only play lead up higher than that. Hence the bias for being able to hit the strings harder in the lower part of the neck suits me.

Buy some grain filler. I use a product from Feast & Watson that is basically shellac containing lots of powdered stuff - talc or pumice or something I suppose. You slap on a few coats on the bare wood and sand it back level. You'll also find a lot of talk about grain filling with a bit of searching around here. I've read of people using epoxy, or CA glue even.

Now you're talkin'. Lagavulin for me (but I'll accept Laphroig and Ardbeg at a pinch too)

As an Aussie I still like the old "Billy Tea", but Twinings is great for the fancier stuff. I'm a bit of a fan of their Earl Grey tea actually as well. Oh, and welcome

What I do is hold down the 1st fret with my left hand, then reach over the guitar and put my right thumb on the 24th fret, then stretch my fingers out towards the nut, and I find I can then push the string down somewhere near the 7th fret with my middle fingertip. Pressing it down let's me more easily see how much gap there is.

I used to have an old Aria acoustic with a bolt-on neck and zero fret. Ahead of it's time (1970s)? Maybe I should use a zero fret on my next build... Wow deja vu Yes that's exactly where I end up! Only this morning I was thinking that I should just avoid that damn open C. I just don't like playing for long periods of time using the 'A' chord shape with a bar chord at the 3rd fret. I guess some chord substitution also helps it not sound so boring as well - open Cmaj7 is cool, and throw in some 6th and 9ths, fit it around the melody and it's done

Now this is new to me. It's obvious now I read about it. Thanks for the great links - something for me to read and understand

Yes, very interesting. Long ago, I developed my own method of tuning a guitar - maybe others use similar methods too, that results in a compromise that works, mostly. Much of what you wrote, explains why it works, sort of Once the guitar is roughly in tune, I tweak each string to match the high E. I started doing this to avoid the progressive error you get if you use each string to tune the next one up - as advised in many guitar books long ago. First I tune the low E to be exactly one octave below. I tune the B string open, against the high E fretted at the 7th, then check it by fretting the B at the 5th, against the open E. Often a compromise is necessary here if intonation isn't exact. I tune the G string to the high E fretted to the 3rd. Then the D string, fretted the the 2nd, is tuned against the open high E. Lastly the open A string, against the high E fretted to the 5th. I find the result is a better compromise for the way I play most chords. Except on occasion, and open C chord will sound sour - and this usually means tweaking the G string further - particularly if it's a thin unwound G..