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Hi Gang:
I recently purchased Roger Siminoffs new book on tap tuning. I figured I needed to bring some method and repeatability to my madness. I bought the recommended software and set up my laptop to measure the various tones produced by a new test guitar. The guitar is a mahogany slope shoulder dread built out of free leftover bits and pieces.
The tuning of the top was confusing at first but it now seems to be fairly close to Siminoffs figures. The overall bridge plate tone is right on the money (A#), I can hear differences in the small brace tones but can't accuratly measure those sounds as the whole back sound overpowers the tones the mic hears.
However, the back assembly right now is at A (107 Hz.) Siminoff wants this piece to resonate at D (73 Hz.) If I shave and sand the back down to that thinness I'm sure the whole thing will explode into a big bag of splinters and wire. Am I missing something? can anyone explain? T.I.A.

Perplexed in Reno....

_________________
The Biggest Little City, Nevada
www.hammondguitars.com
I love building guitars!

Try thinning the plate around the edges. I normally take my edges to around 1/16 inch for a distance of about one inch from the edge.

I would like to know more about the technique you used to measure the frequency. Specifically the equipment used, how you set the microphones, etc.

I've already thinned (significantly) 2+ inches around the perimeter and the back braces are down to 3/8" tall. That lowered the frequency maybe 20 Hz. I need to go another 30 Hz., IF (!) I am understanding what Mr. Siminoff is driving towards.
Siminoff recommends using the Peterson Strobosoft software, its available online. The software makes your computer act like a typical instrument tuner. He says almost any microphone will suffice. I feel the software package will be very valuable as I continue to build instruments. The typical laptop makes a very fast, sensitive measuring tool that can go out into the shop if needed. Maybe my knowledge of the musical scales, octaves, etc. is where I'm confused?

_________________
The Biggest Little City, Nevada
www.hammondguitars.com
I love building guitars!

Mike,
I too purchased Rogers dvd/book. I think you are missing several key points. first that you don't always shoot for an A# tunning or a D, or a G, or for any note in particular. It much more than I can write here. If you re-read the book I think it will clear things up a little for you. I don't mean for this to sound nasty or harsh, it's just that re-reading is probably what you need.

_________________
Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

Dave:
Your point is well taken, I was trying to achieve the tunings as shown in appendix C. Have you any experiencewith Siminoffs guidelines? When he says a "D" note, which octave is he referencing? How do you feel about the validity of his techniques?   Thanks for the reply...

_________________
The Biggest Little City, Nevada
www.hammondguitars.com
I love building guitars!

Hi Mike,

I'm thinking of buy the book.  But at the moment am curious to know; what is the recommended software?

For the last couple of days I've been trying to program my own tuner program, works, sort of but not really.  At this point I'd rather not mess around with programming and signal processing. So I'd buy a program if there is one.

Also, for tap tuning can you use the digital peterson virtual strobetuner?  I know that some folks use a peterson strobotune to tune their braces.  But maybe that digital thing requires a longer signal to process.

Thanks all,

Stefan

Whoops,

I read through the posts again and saw that it is the Peterson program.  Sorry about my redundant question.

Stefan

Hi Mike,
If you look back several weeks there was another thread That I commented about Roger's book/dvd. I think, based on my learnings from Master Somogyi, That Roger has very valid points. I believe, however, that when he (Roger)said he was tunning to A# and the back to D it was in reference to something he found works for HIM with a specific wood and a specific deflection reading. There is more to it than that and that is why I think you (I also need to re-read... I learn slow and forget fast) should re-read the book to get the concepts down. I don't think he was saying "try to tune your top and bracing to A# and then tune your back to D". I have the benefit of having studied with Ervin Somogyi, and these concepts are not new to me. I can't tell you what Ervin recommends. Ervin asked his students not to divulge specifics, so out of respect for that request, I won't give specifics as to what he recommends, BUT I will say that he doesn't say "ALWAYS tune your back to this or that"...he recommends so many semi-tones from the top. Even that has variables of choice so I guess it all comes back to what works best for you.
I do like Roger's approach and recommend his book/dvd. As far as Ervin's Class goes...ask Brock and Tim how adamant I was that Ervins class was life changing. If you can afford it... take Ervin's class...it will make you "see" things only Jedi have seen.

_________________
Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

p.s.


I have/had several peterson tunners...they are all good. The program(which I don't have) is probably as good as any of there other digital strobes...however... "they" say that digital is not as accurate as a real strobe because using a real strobe allows the human eye to select the accuracy of the note being tunned where as the digital strobe utilizes a digital projection onto a screen and has certain restrictions ( or burn points). Therefore the most accurate is the "real" strobe.

If you can afford it, buy a real Strobe Peterson. If not, you might want to try the new Turbo Tune Strobe tuner which sells for around $120 bucks. I like it but have NOT checked it formally against the Peterson (I have the 490 stretch Strobe). Any way, the benefit of having a small Strobe on your work bench vs. a Computer (even a laptop) is why I opt for the tuner over the Program.

_________________
Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

Dave;
Your statment makes sense with the addition of the other info from the school. If this was easy I guess everybody would be building. Another thing I've noticed is that the Peterson software and my laptop does not read pitch exactly the same as my cheapie Korg tuner, which one is closer I wonder?

_________________
The Biggest Little City, Nevada
www.hammondguitars.com
I love building guitars!

don't you have a tuning fork? they are very cheap and reliable, and serve as excellent tools to make such comparisons, calibration tests, etc. i use it each time i fire up the peterson. did the same through several conns. never did trust their auto calibration.

I'm told that the little tuners tend to go with whichever is the strongest partial. It may not be the fundamental.

I heartilly second the caution that Roger's numbers are most likely the ones that work for him, and may not work for you. I have not read his book, so I can't speak directly to it. However, I'm another of the 'tech' types, and I can tell you that there is no magical recipe that will apply to all guitars. Even very small alterations can make a difference in the way things work, and unless you are taking very complete measurements of things like wood properties, you are going to miss some stuff that is potentially important.

What good guitars do seem to share are consistent _relationships_ among the parts. Things have to work together. Part of becoming a good luthier is learning what those relationships should be, and when, for example, a larger or heavier bridge might be called for. This will vary, depending on how a particular top works, the style and wood of the body, and the sound you want to get.

Try to figure out what the underlying system is that Roger is setting forth. How does he say the guitar works? Where is the sound coming from, and how do the things you're doing, like manipulating the braces, alter that? If you can derive a consistent picture of this, and see how the work you're doing gives you effective control over the variables, your work will become more consistent. It won't if you just follow some recipe without understanding why it works.