Australian/New Zealand Luthiers Forum

John Charles (Chuck) Herin

chuck @ pegheds.com


Regards,


Edzard

Trevor,

Thanks for your input. I will have an other look at VA/Windows/USB mics and come hopefully back with some better results.



Best regards,



Edzard

Thanks Craig!

Found this neat construction. It's from Michael Cone ( http://www.coneguitar.com/acoustics/a02.html)



Edzard

Hello All, Please tell me/confirm to me that the spindle of the (analoge) gauge your all using goes "through" the housing of the gauge... Other wise I'm going nuts how this works with the above jigs! I'm asking because (a) I want to build one of my own and (b) I have a few digital gauges and there t...

Thanks Trevor! Some of the above pictures are with the setting as you described in your paper and I took a few with 20X.

Makes not that much difference.




Best regards,


Edzard

Are the above samples sufficient or should I explore other options (an other mic?, older laptop?).

Thanks again,


Regards,


Edzard

After some more adjustments (changing the sample rate to 20 x) I get the following results. Schermafdruk 2015-11-04 20.23.28 20 piano.png Schermafdruk 2015-11-04 20.24.46.png Schermafdruk 2015-11-04 20.25.33.png Sample rate 10 x Schermafdruk 2015-11-04 20.29.12 10 piano.png Schermafdruk 2015-11-04 2...

Hello Craig,

I'm not into violin building so I can't advice any good books.

But this contains a lot of info (also some guitar related stuff) for the coming winter (at least over here)..

http://www.oac.cdlib.org/findaid/ark:/1 ... /dsc/#ref1



Best regards,


Edzard

I have the VA program configured conform your paper "Technical note on collecting spectrograhic data". FFT size is 16384 and Frequency sampling is 11025 (Bandwidth is 0.512 Hz / Spectral line resolution is 0.67 Hz) and buffer set to 10. What I noticed on my Surface (I7 Intel processor) and other new...

I played a bit tonight with the configuration of my system but it seems I'm drifting further away from getting good predictable/reliable results. I turned of the internal mic (although the samsung was the input device) and turned the volume back to 30%. Maybe it's a problem with the system/software....

Hello Trevor, I made a hammer with an eraser. Here's my setup. DSC00061.jpg DSC00062.jpg DSC00064.jpg I made 4 guitars with different tops (2 lutz and 2 euro spruce). They sound all very good (if I can say so). I took a finished one and made some measurements too. First the one without bridge and th...

Thanks for your time and trouble Trevor and Martin. It's appreciated! I have some kneaded eraser. Weight of one package is 21.7 grams. DSC00054.jpg OK. Now a picture without everything. Just for the record. Without.png When I put the kneaded eraser on the top like a small bal on the bridge area I ge...

Hello All, So I thinned the top down to 2.0 mm around the bridge area and 1.9/1.8 mm around the side. When I record the frequency there are no changes. Strange? At least to me it would make sense that you saw some (major) drops. Schermafdruk 2015-10-25 20.36.44.png And one from the back. Back is now...

Hello Guys, Thanks again Martin for uploading the missing picture. I've started sanding this weekend. Bridge area is now around 2.1/2.2 mm descending to 2.0/1.9 around the edges. I took an other spectrum picture but found no drastic changes. Maybe a few Hz lower then before. Schermafdruk 2015-09-26 ...

Thanks Guys, Trevor, the back is from Maple. It's around 2.5/2.4 mm. I totally forgot to make spectrogram with the bridge on. I can't upload a picture (Could not upload attachment to ./files/775_cb2370524add7a529aaee94c9b1be39f.) probably some system configure error, But the peaks are at 280 Hz, 400...

Hello All, I build a few years ago (BG..:-) ) a classical guitar with a (rather) stiff Lutz top, maple back/sides and Romanillos bracing pattern. The bridge was made from African Blackwood. I made it a bit smaller (16 x 25 cm) to keep the weight on the "low" side (19 gr). The top is around the bridg...

Hello Trevor and All,

Can you Trevor or maybe someone else give me a hint where to find the adjustable brass blocks used in your compensating fixture?

What kind of bit are you using to route the nut? Just a regular (wood) bit?


Thanks,



Best regards,


Edzard

Looks like you guys had a lot fun!

Looking at the (empty) bottles in the back, I think I found the reason why my guitars are not so good...yet.

Need to upgrade my shop soon..



Best regards,


Edzard

Thanks for the reply and tip!

I will give it a try.


Best regards,


Edzard

Hello All, I several tops where I have troubles finding the Cross Grain mode. When I tap/recored I find (mostly) two frequencies which stand out. For example I have this top: Excel.jpg And the following recordings: Twinsting vibrationmode (fLC) at 59 Hz. TEST-FLC.jpg Long grain vibrationmode (fL) at...

Thanks!

Somehow I missed that thread completely.


Very nice rosette BTW!


Edzard

Hello Trevor, Thanks for making these books available and taking time to answer questions about them. I am starting to measure some tops and building up a small database like you did in table 4.5-3 "Measured elastic constants and thickness targets". I have "implemented" the equations in Excel and th...

0.01 is the smallest.

There is no automatic sweep.



Regards,


Edzard