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I was laid up for a few weeks with a persistent head cold, and watched a lot of videos. Then I got a sore back from coughing, and now I'm trying to get my brain back. I had to downgrade the 3rd level irregular sudokus to the 2nd level, and still couldn't get them. I've finally done a couple in a row. It's amazing how quickly your entire body can degrade.

Anyway.

Watching videos has me thinking about balance. Many instruments don't have any. I watched one on a test of a bunch of brands of classical strings; pretty much useless. The basses were all good. The mids were fairly chimey. The top e? The top e? It always sounded strained. Somewhat dead. Even the open e.

Another thing; microphones and recording. The iPhone used at first sounded better than the mic used later; I don't know what it was, I don't know anything about mics. The "real" mic amplified the already great bass, and supressed the already dismal highs.

So mics, and amplification are a part of the story. But the instrument is the biggest part. If the instrument won't allow the high strings to sing; what good is it?

What is it that lets the high notes sing? These didn't sound rubbery; I don't like rubbery at all. They sounded like they were far too stiff. So tight that they can't vibrate right. Like an acoustic with 12's that really needs 9's or 10's. It can't just be the strings; something isn't giving the strings any support? A short little chirp, that decays, and dies. Watching videos of great sounding instruments of current makers, and Torres on Guitar Salon International, (whatever mics THEY use are phenomenal.) you can see that the high e shouldn't sound like that.

What is missing? What went wrong?

Like I said. It is a vast subject.

Is it mostly the instrument? What kills off the highs? I arched the cross braces on my Stauffer down to nothing. When I play on the high e, the body still rings. It isn't the strings ringing, it is the whole body. So what kills highs?

Are the strings just too stiff? It's hard to believe that all of them would be too stiff. Is the body too stiff? The best sounding to me were La Bella Flamingo Negra or the Hannabach silvers. No mention of what tension they were using. Pro Artes were loud, not necessarily better; but none sounded great. At least the La Bella's had some sustain.

Are mics like cameras, where sometimes they just don't reproduce the colors/sounds ANYTHING like reality?

Man, I have lots of questions.

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Why be normal?

Hi Ken,
I'm assuming you are talking about nylon strings. When building nylon string instruments achieving good high notes is what we strive for - good bass notes come more easily. With steel strings it is the opposite - high strings will ring forever and bass notes often need improvement.
Gut strings can sound a little better, but the cost and durability are limitations which make us use nylon. Some string makers advertise "Nylgut" and are trying to make a nylon string sound more like gut.
Some Classical builders use a modified Torres design that uses a slanted brace that shortens the fans on the bass side of the soundboard. I don't know if they are trying for overall improvement or trying to kill the bass a little bit to balance the not so prominent high notes.
So you have found the quintessential problem of building a great Classical guitar.

P.S. Do those great sounding " La Bella Flamingo Negra" strings fly off the shelf? ( did spell check get us again! )

Clay, I do have light nylguts on the Stauffer. It just has 3? cross braces; and some tapering of thickness of the belly toward the sides. The braces look like a violin arch. Nothing like the plan. I haven't done a fan brace yet; or an X brace. The arch tops are X arched, and parallel braced.

Maybe cross braces need to be quite stiff for steel strings, and can be drastically cut back for classical? At least on lightly strung classicals with shorter scales.


I do think that the Negra strings are black, and not pink.

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IMO good basses come from the overall size and design, while good trebles are a function of getting the top to work well within itself. Too much of an imbalance in weight/stiffness between the top and the braces, or too many hard and soft spots tends to 'quench' the trebles. These things can often be diagnosed to some extent before the top and rim are assembled, by flexing, tap tones, or Chladni patterns, depending on your orientations. I have so far found astrology, tea leaves, and Ouija boards to be less than reliable., but that's my opinion.

You can, of course, find things that, at first blush, look like contradictions. Smallman's 'lattice' bracing uses a top of veneer thickness, and a lot of stiff CA/balsa 'I' beams, and gets good treble, but in that case the top itself is only there as a membrane to move air, and all of the structure and tone are in the lattice. Archtop guitars, OTOH, get all of their top stiffness from the arching and graduation; the two 'A' or 'X' braces are just there to replace the stiffness that's lost when the holes are cut. In both types the actual stiffness/mass distribution that counts is kept pretty smooth.

Many top brace patterns can be made to work well so long as they get the necessary strength/stiffness where it's needed (on flat tops with tie/pin bridges, the point between the bridge and the sound hole, and, of course, across the upper bout. You have to strike a balance between how easy it is to build and how much control you have over the mass/stiffness distribution, and, of course, each different pattern will tend to have a different timbre. AS usual the 'standard' patterns are good places to start, since, as Pye said: "...it is inconceivable that all of the designers of ten or twenty generations will have been fools".

All of this is especially true on Classicals, since there is very little energy in the higher part of the string spectrum after the initial pluck. Good design and careful work are needed to avoid wasting any of the little you have.

Hi Ken,
I sometimes listen to the K pop group Blackpink when I am mindlessly playing solitaire on the computer late at night. And occasionally a little Flamenco music as well.
Personally, I don't think X bracing works as well as fan bracing for gut or nylon strung instruments. I had an early Martin !-26 model that was in like new condition for a 100 +year old guitar that sounded wimpy compared to most fan braced guitars. Martin Classical guitars are not highly regarded by players and often are X braced or combine fan and diagonal bracing schemes (G series) Some have been prime candidates for conversion to steel strings.
In many ways classical guitars are easier to build than steel string guitars, but much tougher to build well.

Alan, coming from the violin side of things, I gravitate toward flexing, feel, and tap tones. I like if it has a lot of different sounds. I like them to be pretty flexible. They won't be that flexible when they are glued on the ribs. And then you can make them thinner after, if you want/have to. I never had a speaker to do Chladni patterns!

Even graduation, and elimination of thick points are key on carved tops. Even bracing seems like it would be needed on flattops to reach the same goal. The Torres plans I have don't look over braced.

So are there any big pits that people fall into that kills the trebles on a classical?

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OK, disclaimer - I hesitated to post this as I have only one experience of building nylon strung guitars but if it helps.....
Thought I'd post this pic of bracing used on a hybrid nylon strung I helped a student make a few years ago.
Turned out nice, strong bass and clear sweet trebles, with the right strings.
The trebles will never rival a steel string of course, but with SAVAREZ 540J Alliance HT Classical Guitar Strings High Tension (fluorocarbon) there was a marked improvement with the sound of the trebles compared to regular Pro-Arte nylon strings.
Design wise the bracing I actually based on Taylor's nylon string bracing, slanted lower cross bar, with a 1 mm spruce bridge patch and 5 fan braces (6 mm square), and the body shape was an OLF SJ (as insisted on by my student) so it was very large for a nylon strung guitar and I was worried that the energy of nylon springs might be too low to drive the large lower bout and might result in weak trebles.
Worked out quite well though, possibly helped by the German Moon Spruce used for the top and bracing.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Colin, when you see the thicknessing of the fan braces, it isn't hard to translate that into a belly that is maybe 3-3.5mm thick by the bridge, tapering to 1.5-2mm or so at the edges. Like a thicker oil pan casting, or one with ribs cast into it. At what point does the pan with ribs win in weight and strength? On air cooled engines, the ribs could add a cooling function; but that is outside of what we need in guitars. Add a couple cross braces either side of the sound hole. Fan bracing is simpler, and maybe faster and more repeatable than hand thicknessing.

How about "loading" the bracing?

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Why be normal?

Ken—

Switching gears to what you wrote about microphones and recording:

A common saying of questionable origin is that writing about music is like dancing about architecture. That is to say, when you try (or anyone tries) to describe in written words the things that you hear in a recording, it is very hard to convey any real substance to someone who has not heard the same recording. If you could post links to the videos you had in mind when you wrote what you wrote, that would help others get a better sense of what you are talking about.

Sorry, you've lost me almost completely.
Upper transverse brace was flat, then lower brace 28 foot radius, as was the lower bout.
Spruce was very light at 0.366 SG, top thickness was 2.55mm tapered to ~2.2 mm in a U shape round the lower bout, with a block plane, after closing the box.
The 6mm square fan bracing was notched to fit over the 1 mm bridge plate, parabolical section, and tapered to ~0.5mm each end when finished.
And I don't recall ever seeing a fan braced nylon strung guitar (I have the Courtnall book) without 2 cross braces, above and below the soundhole, of some kind.
YMMV.
Loading? - is that pre-loading the braces? Braces were cut straight and then pressed into shape in the radius dish for gluing, same the spruce bridge plate.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Colin, you don't sound lost. Your braces were loaded. Do you think that makes any difference at all? Some makers say they add load to their violin bass bars. That has to make them stiffer, doesn't it? Sometimes they say a bass bar is worn out? They take the top off, and re-bar it. How could that be, unless the induced spring has taken a set, and no longer springs? But you won't hear anyone say that.

You go back over the glued up box, and add spring into the top by thinning toward the edges. That's what that is essentially doing, isn't it? Adding spring, by tapered thinning.

Did you think I was saying to add 2 more cross bars? No. I was just imagining the very tapered belly, taking the place of the fan braces, like the Vihuela I'm starting has, and then adding the two cross braces the the Vihuela has.

I like the shape of your fan braces. I don't understand the ones with spikes all over them.

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Don, I get what you're saying. Here are what seems like good mic set ups. Not sure what they are. A nice acoustic arch top, and then some classicals. Then the link for the string test. I can't tell much of anything from the test.

https://youtu.be/FEWgPL4ox7Q

https://youtu.be/8YBDmbz5TjY

https://youtu.be/IRmQeB62d3k

The test: iPhone first, then a real mic

https://youtu.be/X0v1ihggwT8

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Why be normal?

Ken--

OK, at least I have a bit of a better idea of what you were talking about regarding the last video, the one comparing different types of strings.

It is interesting to me that you preferred the sound of the iPhone recordings to those of the recordings made with the Lewitt microphone. To me, when I switch back and forth between the iPhone recordings and those made with the Lewitt microphone, the thing I notice the most is the difference in the bass frequencies that were captured. And I think it is important to phrase it that way: What was captured by the two different microphones. Think about the variables. The instrument didn't change, and the player tried to play the same piece the same way every time. I suspect the microphone placement did not vary. While I am sure the different strings have different types of tone, that doesn't explain the consistent differences between the iPhone recordings and the Lewitt recordings. you can consistently hear that the iPhone recordings captured less of the bass frequencies. That is pretty much all about the placement of the microphone, the type of microphone, and the processing of the microphone's signal. All of the iPhone recordings share a common microphone and processing (all internal to the iPhone), and all of the Lewitt recordings share a different common microphone and processing (described in the notes accompanying the video).

We could talk for a long time about all of the nuances of trying to make a good audio recording of an acoustic guitar (steel string or classical). There is a lot to consider in that endeavor. YouTube videos are all over the quality spectrum. If you start with something OK, like the Lewitt microphone used in the second batch of videos, and run it through an OK interface, then you are on a good path. The real key at that point is microphone placement. If you put the mic too close to the guitar, you only get a skewed sense of what the guitar actually sounds like. Plus, if you place the mic near the soundhole, you get boomy bass. The best mic placement is 1.5-3 feet away, not right at the soundhole. But if you get too far away, you pick up a lot of room noise. It's a balancing act.

Anyway, for your purposes, I don't think you should draw many conclusions from any YouTube videos about how good or bad a guitar or any certain strings sound. As you suspected, the method of recording plays a huge role in what you hear. The things you didn't like about the Lewitt recordings could have been caused by the microphone placement (probably a bit too close to the guitar) or the use of compression in the processing (again, this was described in the notes accompanying the video). Unless you can count on the recordings being done well, and consistently, I'm afraid comparisons like this are of pretty limited value.

Don, Like Clay said, if the bass isn't as strong, the weak trebles sound better. Not good, just marginally better.

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Why be normal?

Understood, Ken, but the question remains: Does that guitar, in that room, sound balanced? The recordings don't help you figure that out, because the recording equipment and recording techniques leave you wondering. Are either the iPhone recordings or Lewitt recordings "accurate"? Or are either (or both) messing with the sound enough where you really can't tell what that guitar really sounds like in that room? I think it is entirely possible that the iPhone (and its placement in the room, and inherent processing) unnaturally de-emphasized the bass. I also think it is entirely possible that the Lewitt mic (and its placement in the room, and chosen processing) accentuated the bass too much.

The other YouTube links exhibit better attention to the process of recording an acoustic instrument, but boy, when it comes to this topic, let me say, everything matters. The player, the performance, the guitar, the placement of the player/guitar in the room, the room size and shape, the placement of the microphone in the room relative to both the guitar and the walls in the room, the type of microphone(s) used, the settings on the microphone(s), the type of preamp, the settings on the preamp, the processing after the preamp . . . It all matters. As I mentioned before, YouTube videos are all over the spectrum in terms of audio quality. Trying to accurately memorialize how an acoustic instrument sounds in a room can be tricky business. If you keep it simple and use good quality gear placed in rational places, and don't go crazy with the processing later, it can be low stress and it should sound fine. Maybe not Voice of God great, but fine. Going for great, and failing, can often lead to something that sounds horrible.

Here is a link to a guitar that OLF member Simon Fay (Toonces) built, and is being played by someone who not only can play well, but has a good head on his shoulders for recording an acoustic guitar:

https://www.youtube.com/watch?v=WCBB1wQob5E&t=243s

I think this is just wonderful.

Yes Don, that is nice, but it does prove what Clay presented in the beginning; Steel strings have great treble. But does the bass balance out? To me it doesn't, but then I've NEVER been a treble guy. My ears are starting to work for me now. I'm not a fan of rock solos all above the 12th fret. I don't like the crazed out bass of the cars going down the road that shake the windows, but I don't like what you normally hear on a radio, or very old recordings.\ either.
To me this performance is outstanding, and the instrument is what I would call very well balanced. It also has varying timbre on different strings, how far up the board you are, and how and where you excite the string. Obviously only a master can do that. But an instrument, and the proper set up of everything is needed.
Again GSI seems to know what they are doing.
https://youtu.be/98oyvmwWde4

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And then there is the other end of the equation - the sound card in the computer and the speakers it is sending the signal to.

I just thought when I went to bed last night, that GSI might just have a great equalizer setup. That doesn't say that the guitar doesn't sound great, just that they make sure to capture everything. And more? Except for heavy metal, that I'm not into, most music seems to be treble biased. Boost the bass up a couple, and maybe turn down the treble one notch, and it sounds better. Your ears may vary.

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As Clay referenced, your playback environment and system matter a lot, too. Take everything I said about the factors I mentioned regarding making a good recording, and think about those in reverse. You have a set of digital to analog converters, any processing of the signals, an amplifier, speakers, the size and shape of the room in which the speakers are placed, where the speakers are placed in the room, the other contents of the room, where you are situated in the room, and where you are situated in relation to the speakers.

And then there is the question of subjective tastes and preferences, as you reference, Ken. In the end, you can wring a lot of the subjectivity out of audio recording, but we each like what we like, and that varies.

There was a video not too long ago where GSI talked about their video production, and stated that all their recordings are flat EQ'd with no reverb or compression. The room in which they record is obviously very nice, and their mics and recording equipment are probably quite high quality.

The guitar in the video you linked is Tarrega's 1888 Torres, a very important guitar. It sounds like you've been trying to decide on how you'd like to approach a classical guitar, and I would suggest that starting with the plan for this one (which is available from the GAL) and staying as close to it as possible will produce an excellent result.

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Ken I have found that lightness of bracing has been the most important thing to get good trebles. I have been building to Torres SE114 design and reducing the brace heights with each build to now match what the drawing says they should be. And they are small!

You can then get into trouble with some treble notes coming over stronger than others not actually wolf notes. This is not something I've learnt to control yet.

Thanks Dave. The cross braces look huge. I cut mine on the Stauffer way down; but it is the size of the small Torres.
Using a truss rod?

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Yes those cross braces do look tall. The photo perhaps exaggerates them a bit. But since the major sound production is from the lower bout I think that’s where we have to concentrate. They are based on the Torres design.

The top transverse brace is really there to reinforce the upper bout. What is not shown is that I also use Trevor’ Gore’s notion of a block between the upper transverse brace and the head block, both to again reinforce that area and to support the fretboard extension.

Yes I do use a double acting truss rod. Seems silly not to.

Best Dave