Search found 423 matches

by johnparchem
Wed Aug 28, 2019 9:36 am
Forum: Instrument Builders Forum
Topic: First Flamenco Guitar.
Replies: 3
Views: 636

First Flamenco Guitar.

This is my first Flamenco Guitar built following the Paco Chorobo video class offered by Robbie O'Brien. It was a fun course to follow as it include a lot of slide visits and interviews in the Spanish flamenco community. Paco Chorobo is an outstanding flamenco guitar builder and a wonderful flamenco...
by johnparchem
Thu Aug 08, 2019 12:48 pm
Forum: Instrument Builders Forum
Topic: Finish (shellac?) repair suggestions on Spanish classical
Replies: 8
Views: 1098

Re: Finish (shellac?) repair suggestions on Spanish classical

I have never seen that with shellac even from heat. It seems like on the way to refinishing you can try and sand it out. I have used behlem qualasole for repairs on top as it sticks to nearly anything and can be padded on. I have done whole tops with it and it builds quickly and looks great. I think...
by johnparchem
Thu Aug 01, 2019 6:41 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: VA, opening saved files
Replies: 7
Views: 446

Re: VA, opening saved files

Whoops,

you can always hit the capture spectrom button and after the buffer fills it will open a window that should allow you to open a file. That is one of the ways I get a window.
by johnparchem
Thu Aug 01, 2019 2:25 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: VA, opening saved files
Replies: 7
Views: 446

Re: VA, opening saved files

If you want to open a .tee file (waveform) On the bottom right hand control panel, I select the more tab and then spectrum.
va file open 2.JPG
va file open.JPG
va file open.JPG (23.21 KiB) Viewed 439 times
by johnparchem
Sun Jul 28, 2019 2:09 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Advice on Resonances
Replies: 7
Views: 516

Re: Advice on Resonances

In general do not look at the amplitude of the peak as your test setup really is not accurate in terms of relative peak amplitude. It is really showing you the locations of the resonances on the frequency spectrum. The resonance frequency values and bridge rotation are better indicators of stiffness...
by johnparchem
Sat Jun 22, 2019 11:27 pm
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Gore method/Tap tune/Siminoff...help!
Replies: 13
Views: 1347

Re: Gore method/Tap tune/Siminoff...help!

I have a bit of trouble answering a question about "the Gore method" as I think it mischaracterizes the Design volume as it is not a method book. Also the Design volume is not about "Gore type guitars". What is taught in that volume has a lot more inclusive has more depth and is more applicable than...
by johnparchem
Sat Jun 22, 2019 12:32 am
Forum: Instrument Builders Forum
Topic: Guitar top and back radius position
Replies: 13
Views: 2424

Re: Guitar top and back radius position

If the side template\profile is correct and the are sides cut very close to the profile and the waist is bent in the correct place, one can have the sides very close to the correct size and radius with minimal sanding by driving the bus.
by johnparchem
Fri Jun 21, 2019 7:30 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Gore method/Tap tune/Siminoff...help!
Replies: 13
Views: 1347

Re: Gore method/Tap tune/Siminoff...help!

Thanks for your comments on the website. As you see I photo document all of my projects. I think that a lot of the big (factory) boys, have a bunch of parts made to pretty exact dimensions and assembles guitars from those parts in a constant way. The parts are probably sized to hit the center of the...
by johnparchem
Thu Jun 20, 2019 8:57 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Gore method/Tap tune/Siminoff...help!
Replies: 13
Views: 1347

Re: Gore method/Tap tune/Siminoff...help!

When I read your three choices, from your descriptions it seems like there is only one choice. "1". I never understand when i hear that Siminoff is more doable than processes in The Book. I read 'The art of tap tuning" and watched the DVD that came with it. There is no prescriptive method and in the...
by johnparchem
Mon Apr 29, 2019 12:07 am
Forum: Instrument Builders Forum
Topic: Finished Pernambuco/WRC contemporary classical guitar.
Replies: 4
Views: 1039

Re: Finished Pernambuco/WRC contemporary classical guitar.

Here is a video my guitar instructor Doug Rice tring this guitar. His main guitar now is one of my falcate classical guitars. Here is his description of the sound he hears from this falcate bracing pattern. " Their superb basic tone color and resonance, especially their high overtones presented a ha...
by johnparchem
Sat Apr 20, 2019 6:45 am
Forum: Instrument Builders Forum
Topic: Finished Pernambuco/WRC contemporary classical guitar.
Replies: 4
Views: 1039

Re: Finished Pernambuco/WRC contemporary classical guitar.

I do have spectrum graphs of the tap for this and the Osage Orange guitar I posted last week. You will see they are very close. The Pernambuco has a sound port which accounted for the higher Air resonance. I am not sure what the cutaway does to the air resonance T(1,1)1, I do know the sound port wou...
by johnparchem
Fri Apr 19, 2019 9:14 am
Forum: Instrument Builders Forum
Topic: Finished Pernambuco/WRC contemporary classical guitar.
Replies: 4
Views: 1039

Finished Pernambuco/WRC contemporary classical guitar.

My last complete instrument for a short time (I promise.) It is just that I had two going on and the scheduled Ukulele class. In any case this is a "Contemporary Classical" Guitar. I get it, an oxymoron. The basic body shape is a Hauser 37 with the cutaway added. The contemporary features are a bolt...
by johnparchem
Tue Apr 16, 2019 9:52 am
Forum: Instrument Builders Forum
Topic: Acoustical effect of back woods
Replies: 25
Views: 3961

Re: Acoustical effect of back woods

I held off giving my own from my hind side comments on blind listening tests mainly because of where I am pulling them from. Here goes ... Part of the context for my point is that humans are not like a microphone and a computer, we do not hear reality rather we have learned through evolution and in ...
by johnparchem
Tue Apr 16, 2019 7:56 am
Forum: Instrument Builders Forum
Topic: Just Finished Falcate braced Osage Orange\WRC classical
Replies: 4
Views: 982

Re: Just Finished Falcate braced Osage Orange\WRC classical

J Of the bridge I notice that you have quite a lot of saddle showing. Is that due to trying to keep the bridge mass down? And I see that you haven't gone for the twelve hole string tie. I rather like it for the good and more regular break angle though I still have to think quite hard when putting o...
by johnparchem
Tue Apr 16, 2019 3:21 am
Forum: Instrument Builders Forum
Topic: Just Finished Falcate braced Osage Orange\WRC classical
Replies: 4
Views: 982

Just Finished Falcate braced Osage Orange\WRC classical

I strung up the guitar a few days ago. I properly set up the guitar today. I do not have any post build modal tuning I will do right now as the spectrum plot T(!,1), backed up with strobosoft are 93 Hz - 190 Hz and 244 Hz As this one's for me it kept be pushed to the back burner for other commission...
by johnparchem
Mon Apr 15, 2019 2:06 pm
Forum: Instrument Builders Forum
Topic: Tenor Ukulele muted note
Replies: 4
Views: 962

Re: Tenor Ukulele muted note

Paul Henneberry wrote:
Mon Apr 15, 2019 12:57 pm
Hi John,
nice looking uke. Just out of interest what strings did you originally have fitted?
regards
Paul
Aquila Nylgut strings. I switch to D'addario strings Titanium strings.
by johnparchem
Mon Apr 15, 2019 12:14 am
Forum: Instrument Builders Forum
Topic: French polishing
Replies: 19
Views: 3542

Re: French polishing

In the pictures it looks pretty good. I mostly like to leave the finish looking off the pad so that people will know it is french polished, I have no ridges when I am finished but it is a different look than leveled with sandpaper (which also looks very good). I do three wash coats (just pad it on) ...
by johnparchem
Sun Apr 14, 2019 4:27 pm
Forum: Anything Goes
Topic: Taught my first (and last?) Ukulele construction class
Replies: 2
Views: 865

Taught my first (and last?) Ukulele construction class

I had my first teaching\mentor experience; Lily an 18 year old girl in a one week ukulele course for her senior project. What a trip building an instrument in a week is way faster than I even make them. It turned out nice, and after fixing the neck resonating exactly at 392 Hz cursing a horrible wol...
by johnparchem
Sun Apr 14, 2019 8:02 am
Forum: Instrument Builders Forum
Topic: Tenor Ukulele muted note
Replies: 4
Views: 962

Re: Tenor Ukulele muted note

Thanks Allen,

I did calm down, I went over the instrument fixed a few unrelated things, One change that might have helped was close to the nut the neck was a little squared off so I took that wood off to match the rest of the neck and I went to a different brand of strings. Sounds good now.
by johnparchem
Sun Apr 14, 2019 3:01 am
Forum: Instrument Builders Forum
Topic: Tenor Ukulele muted note
Replies: 4
Views: 962

Tenor Ukulele muted note

I had a niece build a tenor ukulele in my shop. We ended up with an interesting wolf note on the high G string or the A string tuned to a G. Actually a little flat or a little sharp no problem. We put strings on the Uke and strung it up with the neck clamped in a vice as shown in the picture and all...
by johnparchem
Thu Apr 11, 2019 11:38 pm
Forum: Instrument Builders Forum
Topic: Acoustical effect of back woods
Replies: 25
Views: 3961

Re: Acoustical effect of back woods

Thanks Peter, On your first post I had trouble imagining what the control would be. I appreciate your detailed explanations. My understanding from your comments is that without the control, testing with instruments that clearly sound different, we have to assume or be convinced that their methodolog...
by johnparchem
Sat Apr 06, 2019 1:17 am
Forum: Instrument Builders Forum
Topic: Acoustical effect of back woods
Replies: 25
Views: 3961

Re: Acoustical effect of back woods

....The poor ability of guitarists to discriminate under blinded conditions between guitars with backs and sides made of different woods suggest that back wood has only a marginal impact on the sound of an acoustic guitar . I question the study not so much for the scientific methodology and am happ...
by johnparchem
Wed Apr 03, 2019 8:58 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: T(1,1)2 and Back Question
Replies: 10
Views: 1519

Re: T(1,1)2 and Back Question

The low and wide is not a bad way to go, especially because you like your last guitar. Was the plot of the last guitar with a bridge and strung up. Its numbers are within my range of where I would like a steel string. If you just closed up with no bindings, I would consider thinning around the lower...
by johnparchem
Wed Apr 03, 2019 12:37 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: T(1,1)2 and Back Question
Replies: 10
Views: 1519

Re: T(1,1)2 and Back Question

If you thin the back more you will lower its resonance. I would work on the top a bit to loosen it. It will change with a bridge and strung up. You can tune the inside braces after the guitar is strung up and see its finial resonance. Also you can hear it at that time and decide if you want to chang...
by johnparchem
Tue Apr 02, 2019 12:33 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: T(1,1)2 and Back Question
Replies: 10
Views: 1519

Re: T(1,1)2 and Back Question

217 Hz for the T(1,1)2 is what I would have said from the first graph. With the bridge and strings it should come down maybe to 207 Hz or so. Is the top the Martin x-brace design? If so you can reach in and tune the top after the guitar is finished. Low and wide is a lot less stiff than the taller b...