Tuning the top of a d’Angelico New Yorker copy

[paulbiere]

I have a new guitar that was made from a detailed blueprint plan for a D’Angelico New Yorker. It’s sounding really good currently, but I’m wondering what the proper frequency or note that I should aim for in adjusting the top through tap testing. I understand that through carefully sanding the edges of the F holes you can raise the frequency of the top and possibly get a crisper response. Does anybody have out there have one of these instruments, or have a suggestion for answering my question? Thanks.

[Freeman Keller]

Are you building the guitar or modifying an existing one? How are you measuring the frequency of the tap tones ? Remember that to raise the frequency of something you want to make it lighter or stiffer, stiffness generally increases as density increases.

I did some spectrum analysis as I was carving the top of the last archtop that I built but it probably does not correlate with what you are doing. Mine was a 16 inch non cutaway similar to an L5, top thickness varies from about 1/4 in the center to 1/8 in the recurve. Mine is X braced, with small bound f holes. The air chamber resonance came out about 117 and 228 Hz. I could share the spectrums but they might not do you much good.

[paulbiere]

thanks so much for your response.
The guitar was recently completed based on detailed plans for a D’Angelico New Yorker.
The luthier has a lot of experience building mandolins and this is his first arch top guitar. We’re aware that the tap tuning frequency on the top of a mandolin can be raised by sanding the f holes to enlarge the opening.
I am using a strobe app from my phone and get a pretty consistent 138 hz corresponding to C. What I’m wondering is what to shoot for with this particular guitar and was hoping to find some data on the old New Yorkers.

Are you building the guitar or modifying an existing one? How are you measuring the frequency of the tap tones ? Remember that to raise the frequency of something you want to make it lighter or stiffer, stiffness generally increases as density increases.

I did some spectrum analysis as I was carving the top of the last archtop that I built but it probably does not correlate with what you are doing. Mine was a 16 inch non cutaway similar to an L5, top thickness varies from about 1/4 in the center to 1/8 in the recurve. Mine is X braced, with small bound f holes. The air chamber resonance came out about 117 and 228 Hz. I could share the spectrums but they might not do you much good.

[Freeman Keller]

Paul, I am primarily a flat top builder but a couple of years ago I built the 16 inch carved top and took audio spectrums of the "tap tones" as I carved the top and braces. Here are the last two, the first is the carved braced top with bound f-holes, basically the last step before gluing it to the rim


This one is after gluing the top on, the box is closed


The significant change are the two peaks at 117.5 and 228.5 - two A sharps an octave apart. Those are the "main air resonance" and are mostly a function of the size of the box, as well as sound hole size. The other peaks are the various resonance of the top, they move around as I make various parts of it thinner.

When I built my guitar I had no idea of what these resonances should be or would be, I just used the software to try to understand what I thought I was hearing. Benedetto describes the change in tap tones as the guitar is being built but doesn't give any target values. I'm sure yours will be very different from mine.

I will add one other comment. When I finished my guitar frankly I was disappointed. I'm used to flat tops and this guitar seemed overly bright to me. I thought I had biased my build towards the mellow side - it is X braced, the sound holes are fairly small. I spent the better part of the year changing string to try to mellow it, it did open up with age and playing.

I didn't have a lot of experience with archtops and I think that is part of my problem. I recently had a chance to play it next to a very nice Andersen and I actually feel mine held up pretty well. So remember that yours will open up and change with play and as you learn how to play it.

Good luck, I hope this helps.

Mine is on the left

[deacon Mark]

The late Bill Hollenbeck who was one of the original Blue guitar builders for the Chinery Collection, never tuned the top to a particular note. He said that if you did that then when that note was played it would either be a wolf-tone or cancel out and be diminished. He learned with from Bill Barker and Barker never tuned to a note either. He tune the top to respond fullest at the point of contact in middle of the bridge.

Tap tuning a guitar at least from the fellows I worked with only meant that the top was tuned to be as responsive as it could be given certain parameters. The top could not be too thin, or too thick so they had a gradulated carving pattern. Barker got his carving pattern from Carl Albanus Johnson, who made Albanus guitars. He was a well know guy in Chicago during the late 50's and 60's. He was a Swedish violin maker by trade but went on the make guitars at the advice of his guitar friends. Fred Rundquist was his friend and fellow Swede who I think got him going or at least did much to help. Fred played a D'angelico and others and eventually played an Albanus.

My suggestion is not worrying about precise readings from scopes and such but go my ear and feel. It is not a science that each top can be duplicated, but an art to find the greatest responsive top that is also strong and resilient in nature. Bracing pattern has much to do with how things come out. Experimenting all the time is what most makers do. D'angelico's are all over the map on how they are braced and variations. I think in the end it is mostly an art to carve and top and that takes, experience, study, and constant updating of procedures. CNCing a top is one thing, but John Monteleone and Mark Campellone are far ahead of the CNC machine, the machine cannot think outside the box.

[paulbiere]

thanks for your response. Interesting discussion, I’ll post some follow up if we get more information or make alterations. Playing the instrument has definitely opened it up nicely.

[Tom Blatz]

What we are seeking is the main air resonance of a vintage New Yorker .
Thanks for any input, much appreciated!

[Archtop Guy]

Paul, She looks wonderful! Give her some play time,you may find you've already tuned her as she opens up.

[QAman]

It's a known fact the plates change frequencies when they are attached to the sides of the body - then again when the neck is attached. This is precisely why Jim D'Aquisto, and now Bryant Trenier , do the large part of final voicing after the body is closed and then again after the neck is fitted. The top is nearly complete when the neck is put on, but Jimmy and Bryant left the backs full for carving and voicing with the top plate. Its at this point - where a master luthier brings out the magic and full potential of the "complete born" instrument. It's a very time consuming process. D'Aquisto's and Trenier's are very similar in sound, due to this construction technique, which requires confidence while carving without measuring plate thickness. The process relies on purely feel and sound at this point. The " Builders Bench " has further in depth discussion on the process.

The better acoustic Archtops I've played always have a low frequency ( tap tune) on the back. I like to refer to this frequency of that which resembles the thump of an over ripe watermelon. In fact, the better guitars have this low frequency occupying most of the back area - except of course where the neck and tail block reside - and also in the cutaway area.

John D'Angelico knew this for sure. Pick up any D'Angelico and tap around the back and you'll notice he maintained an even low frequency throughout much of the back. It's the back which adds that sweetness (like a ripe warermelon) we all cherish. Also, the great builders tweak in the recures at this point - by pressing and scraping until they achieve optimum interaction and responsiveness / efficiency of sound projection.

John Monteleone gets his plates nearly finished off the guitar , then strings every one up in the raw - which gives him the opportunity to perform the final plate scrapping/ voicing. He then disassembles all the strings and hardware and finishes the guitar.

Once the finish is applied - it changes the frequency AGAIN. But guys like John D, Jimmy D , John M , Bryant T ( just to mention a few) and likely many other great builders know this - and they anticipate that final change. Ive talked to John about this for many years - and played well over 100 of his guitars through the entire process- and its quite intriguing.

Plate voicing is always a great topic for discussion.


Sent from my SM-P610 using Tapatalk

[teeps]

[Hammertone]

....like a ripe watermelon...

Mmmmm..... watermelon...

[jads57]

So being a player I assume this tap tuning is for the acoustic voice primarily. A couple things come to mind about being tap tuning.
Is the top vibrating more and does this affect feedback when electrified?
Also does it become a moot point once a pickup is installed, either floating or cut into the top?

[Freeman Keller]

So being a player I assume this tap tuning is for the acoustic voice primarily. A couple things come to mind about being tap tuning.
Is the top vibrating more and does this affect feedback when electrified?
Also does it become a moot point once a pickup is installed, either floating or cut into the top?

Its one of the ways a builder optimizes the acoustic sounds of a guitar under construction. There are many ways to do it and each builder has his/her own. It often consists of tapping on the top plate with fingertips, knuckles, or a small mallet) and listening to the tone. Changing thickness, stiffness, density, porting and other parameters will change the frequency spectrum (ie. the tone) of the tap. The builder uses this to make decisions about the guitar.

I'm an inexperienced builder, but I still tap my guitars as I build them. It has been very helpful for me to try to correlate what I am doing to what I think I hear. Maybe after I've built a hundred or so I'll start to understand it.

It is rarely done to electric guitars but certainly acoustic guitars with pickups can benefit from tuning the plates