New Luthier Tips du Jour video - Cedar vs. Spruce

[Robbie O'Brien]

Here is the latest Luthier Tips du Jour video. - In this video I invite Australian luthier, Trevor Gore, to explain the difference between Cedar and Spruce.
This video as well as all my other videos are available via my website, http://www.obrienguitars.com/videos , LMI's website or on youtube.
Don't forget to subscribe to my channel if you want to get the latest Luthier Tips du Jour videos when they are released.

youtu.be/fbXv4QVa8fk

[blackalex1952]

I have some questions for Trevor....firstly, what VA setting give that particular frequency display.
? Second question, I have experimented with and measured as well as played a few guitars which have rather thin soundboards. They tend to sound "banjoey" with low sustain, and ones where I have gone a little thicker with the soundboard than the VA/formula method seem to have a thicker tone with a little extra sustain....your opinions please, gentlemen. Cheers Ross

[Trevor Gore]

I have some questions for Trevor....firstly, what VA setting give that particular frequency display.

There's a row of tabs to the right of the ON button. One of them says "Freq. meter"...

Second question, I have experimented with and measured as well as played a few guitars which have rather thin soundboards. They tend to sound "banjoey" with low sustain, and ones where I have gone a little thicker with the soundboard than the VA/formula method seem to have a thicker tone with a little extra sustain....your opinions please, gentlemen.

Did you finish at the target value or start at the target value? i.e. if you take the panel to the target value before bracing, when you have finished binding, clean-up, sanded out the dings etc. you may well be somewhat thinner than target. Over-thinning the edges will also give a similar result to what you describe. I still use all the "f " values in the book, but if you prefer something different, go for it. The "f " number is there specifically so you can change it, if you want to.

[Dave M]

Useful quick overview Trevor.

VA never ceases to amaze me- I had never seen that setting. Presumably it is picking out the highest volume peak...?

Cheers Dave

[Trevor Gore]

Presumably it is picking out the highest volume peak...?

Yes, the highest amplitude peak. Useful for all sorts of things.

[blackalex1952]

Thanks Trevor...I actually knew the bit about the tabs at the top, I,just forgotten and haven't been in the habot of using them. Yes I might be going a little thin with sanding etc. But still curious re the thicker slightly heavier built sound...player who have played my guitars are used to sustain from the overbuilt factory instruments in the market place, and like close bass rather than projection and low inertia top, which I prefer....I like cannons in acoustic session or with loud background voices in a lively room, when most player don't quieten down and control their rhythm volume...a single string is easily outnumbered! I know that Craig Bumgarner has a modified stiffness and resonant target in his spreadsheet which works for the Selmeroids. Cheers! Ross

[blackalex1952]

I have another question. I have spruce boards which were cut from a 1.5 board. In order to achieve maximum yied of soundboard material, the shape 0of a cutaway was taken for each set of boards. In order to approximate a rectangular soundboard, I need some guidance re resonance testing, one half of the board being longer than the other half of each board. If I took the ther resonances I'm getting, depending on where the nodal points are, then measure the deflection of each board at the three points along their length, to a resonance reading to a nodal point at right angle to the edge of the board for the centre length of the board, the outside and the inside length then averaged them into one would I be loosing much using the formlae in the books for an accurate target thickness ie how much have I got to factor in an error? If I cut the boards to a rectangle I would be making ukeleles....Come to that point, what are ideal resonances for the uke family? Cheers Ross

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[blackalex1952]

I tried the frequency meter and it doesn't give a reading? Which is probably why I haven' got into using it...re my resonant figures from the board I sampled, the long side is 89.5 low frequency at its node for the long grain resonance and 248hz for the top resonance. The short side is 88.5/228hz. I guess the long grain lowest is more dominated by the average of the board than the top resonance, but there is only a 20hz difference at these top frequencies. I haven't yet done a bending stiffness at each node where I can hear clarity in the tap at a right angle in ecah case to the board edge. Ross

[kiwigeo]

I've found the VA frequency meter a bit catankerous.....sometimes it works.....other times it doesn't seem to pick up a harmonic.

I tried the frequency meter and it doesn't give a reading? Which is probably why I haven' got into using it...re my resonant figures from the board I sampled, the long side is 89.5 low frequency at its node for the long grain resonance and 248hz for the top resonance. The short side is 88.5/228hz. I guess the long grain lowest is more dominated by the average of the board than the top resonance, but there is only a 20hz difference at these top frequencies. I haven't yet done a bending stiffness at each node where I can hear clarity in the tap at a right angle in ecah case to the board edge. Ross

[blackalex1952]

Robbie, I do a lot of research on you tube re guitar playing and accessing some of my studies. Every time I click on a you tube link at present , you tube defaults to a page advertising your webinar. Is there a workaround as I am a bit over it and it is an unsolicited distraction? Cheers Ross

[Robbie O'Brien]

I have no idea why that is happening. Is it when clicking on my videos or any video on Youtube?

[kiwigeo]

Ross, try looking at the settings for Youtube at your end. I vaguely remember there being some security settings that control automatic redirections.

[blackalex1952]

Any random video...clearing the cookies worked...if it keeps happening I'll let you know, thanks for the replies gents. Cheers! Ross

[OiAcoustics]

I've found the VA frequency meter a bit catankerous.....sometimes it works.....other times it doesn't seem to pick up a harmonic.

I tried the frequency meter and it doesn't give a reading? Which is probably why I haven' got into using it...re my resonant figures from the board I sampled, the long side is 89.5 low frequency at its node for the long grain resonance and 248hz for the top resonance. The short side is 88.5/228hz. I guess the long grain lowest is more dominated by the average of the board than the top resonance, but there is only a 20hz difference at these top frequencies. I haven't yet done a bending stiffness at each node where I can hear clarity in the tap at a right angle in ecah case to the board edge. Ross

Has anybody figured out why the frequency meter doesn't read out consitently or at all? Sometimes I get a clear reading, most times nothing, on two different computers. It's very clear in the main window, just not in the readout...