Folded Horn Acoustic Guitar Patent # 10,777,172

Hmm, interesting, but probably too late for that!
Well on this guitar yes, but the design in your mind's eye, on paper or in that CAD program, or the next patent covers it. Combination cutaway horn exit by the neck, second at the original position at the tail.

Just so you know, I'm having a blast with a Chinese take on Yamaha's Transacoustic system, that drives sound (on mine just the reverb / echo part) into an acoustic guitar body, which in turn radiates that sound off the back surface.

Partly because I've modified it to handle a vocal input as well, which requires a headset microphone. Same thing; just the reverb / echo part of the vocals radiates out from the guitar body. It makes quite a difference in sound on both guitar and voice, when added to the ordinary acoustic output of each.

Regarding your guitar, all mine does is give me the perspective of what it's like to have amplified sound coming out the guitar itself, versus a speaker cabinet over there.

It's a very interesting sensation to have your voice mix so intimately with the sound of the guitar, that too emanating from the instrument you're holding. I'd say if anything it helps one to sing on key, as your voice note is in there along with all the notes of the guitar chord you're playing. How yours will work strongly suggests the same sensation will happen while playing and singing.

Even if you're not a singer yourself, you might want to add a mini-XLR input and level control to whatever embedded electronics you're considering! If you're not yet ready for a full inboard electronics package, it's certainly something to consider when auditioning the guitar to prospective customers, in whatever setup (mixer, effects, amplifier) you use, to be emphatic about how you can sing through it too.
 
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JJ - OK that did it, I just bought a ToneWoodAmp. I have seen good reviews and trust your input, can't wait to test it, I do think it is a great product. Thanks much for your great input, love that last post!

I also have always been impressed by Yamaha guitars and of course pianos, great company. From what I can see, the Yamaha Transacoustic guitar is similar to the ToneWoodAmp, do you agree? I consider Yamaha to be a potential buyer of my IP, fingers crossed.

I also like your idea about different horn exits, and speaker placement. My third Folded Horn Acoustic Guitar body has all the CNC work completed, but I can put the speakers and horn mouths anywhere I want, those areas cut by hand have not been added yet, for that reason, thinking about it.

I also love the concept of vocals with guitar. My Folded Horn Acoustic Guitar has that option also, as there are two channels in this amp that I use for magnetic and piezo pickups. I think this combination is critical for the great sound. There is also an XLR input that I can use for vocals, and very much want to do that, I have this included in some of my presentations. The only reason I do not push it: I am not a very good singer, need help!

The best comment was the music (vocals as you mention) are IN THERE. The music (guitar and vocals) are IN THERE indeed, in my guitar! You think the Yamaha Transacoustic or ToneWoodAmp are great experiences, wait until you hear this Folded Horn Acoustic Guitar. It takes both of these great products to another level, given that POWER is involved (117 dB) and you can play the guitar as easy or rocking as you like, and get unbelievable sound. Plus of course you can add any effect you want, easy.

It will come out when I finally have it finished (and the second patent protects me even more legally). The USPTO is killing me, still no response after a year for the second patent with improvements! I hear the wait now is 1-1/2 years, COVID catch up, not enough Patent Agents, hey I get it, just not thrilled about it.

Anybody that likes the ToneWoodAmp or Yamaha Transacoustic please comment, these are great products, but wait until you hear mine, unbelievable, this is not a marketing ploy. I am just happy people like those products, because they are setting the stage for the release of mine. OK sorry, don't like to blow my own horn much, but needs to be said, let's make the Acoustic Guitar Rock!
 
From what I can see, the Yamaha Transacoustic guitar is similar to the ToneWoodAmp, do you agree?
Thanks! I believe so, although I've never played with the ToneWood device, the Transacoustic only for a few minutes at a local GC.

My Chinese knock-off (I'd call it something but the only id is "M2", which I cant find the outfit where it actually comes from) makes the guitar sound perceptibly "fatter" like all reverb chorus devices do. Same with the whole "singer / player on a stool" package, when voice is brought into that effects mix. Which, IMHO, is the part they all missed.

But you're not going to miss it. Hopefully your instrument will become the darling of all buskers out there, something you can just pull from the case, plug in a mic and start wailing out songs on any street corner! Extra battery in that little compartment where you'd keep your picks and capo, spare strings.
 
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I will try the ToneWoodAmp on my Taylor, and just for fun on my Heritage semi-hollow body electric, you never know. I will also try it on my Folded Horn Acoustic Guitar, should be interesting having this device at a much higher volume level, let's see what she does!
 
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I have the new neck on this guitar, looks great, my wife says: so so :ROFLMAO:

It finally sounds like an acoustic guitar, but of course good and bad news:

When I play a blues shuffle on 5 and 6 string, sounds great!

When I play an open "cowboy" chord with all strings, sounds horrible, WTF?

Turns out my floating nut is great on the low end, and far too low on the high end. It is adjustable and floats, which is easy to fix, but a real problem now. I checked it earlier, must be pounded down more in the pocket, need to adjust, easy to do.

Scared the hell lout of me, I played a cowboy E and it sounded like horseshit. I was like what happened??? Will fix, the fret buzz was horrible.

Plus my neck is dead straight, but a neck does need some very slight relief, so after the nut fix I may need to adjust the truss rod.

I really do not like truss rods, very old Martin guitars do not have them :unsure: they added relief by hand.

The truss rod by definition just adds stress to the neck and fingerboard, but it might be necessary after the nut is fixed.

Anyway, much closer, I do not dare start playing with the electronics until this is complete. Kind of a bummer, because if the acoustic
part was complete, I could have the electronics howling in about 5 minutes. Stay tuned and let's rock!
 
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I found the problem: the nut pocket on the new neck is slightly different than the nut pocket on the old neck. These were CNC features so dead nuts there, but the second neck was squared up on the mill before cutting (improvement) so there must be a little difference there somehow. Plus maybe the nut got filed down a little earlier, not 100% sure how it happened, but I measure the nut to the fingerboard, and it is definitely too low, exactly the kind of problem that will make a guitar sound terrible. I have nut stock and will just make a new taller nut, not very diffiult to do, so I am safe, what a relief!

I was able to play the guitar for the first time, and I found it very easy to hold, even though it is larger, plus the weight did not bother me at all, good news, stay tuned!
 
One of the things I noticed in the reverb body injection system I'm using is that the tuner at the end of the headstock picks up my voice's reverb transduced into the body. I have a Peterson tuner, which works like their strobe tuner - makes for a very easy way to see just what note it is that you're singing harmony to that chord (which you've just silenced).

“If the women don't find you handsome, they should at least find you handy.” => “If the audience don't find your voice handsome, they should at least find you're singing on key.”

I wonder if the vibrations in your guitar (from the speaker carrying vocals) will do the same?
 
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Thank you JJ - so are you saying you can see the tuner either stay on pitch or move slightly based on the pitch of your vocals? I never tried that, very interesting. Can you please provide more details.

I will def put a tuner on my guitar to test this. I started bringing small work on the road with me as I travel for work, have been doing neck/fingerboard/fret work as I mentioned earlier. Last night I did some nut work, have a good set of calipers for measurement and a small file set. I will add the new nut this weekend. The results will be much better I am sure, basic guitar setup, but when you are making many of your own compennts, not just buying a kit, this becomes even more critical.

I am in the perfectly straight neck camp, but a little relief might be needed, as perfection is a nice concept, but not always easily obtainable, given material imperfections, thermal expansion and contraction, string force of 200 lbs. pulling up...stay tuned!
 
Can you please provide more details.
So the setup I'm currently playing with has both a guitar (piezo pickup) and vocal (microphone) input. I have a dynamic headset microphone connected to the vocal in. The device applies "reverb", then amplifies the signal which goes to a Dayton "exciter", which I've cemented onto the back side of the guitar, on the inside of course. This drives the "reverb" sound into the guitar body. Apparently, some of that ends up at the headstock, as my Peterson tuner clipped on there picks it up.

So if I play an Am, and "sing a note that fits in well with the chord I'm playin" it registers an E on the tuner. If I play an E, and do the same, it registers a B. The sound of the guitar dominates, so I have to silence the chord and keep vocalizing to see what note it is. Of course, I'm not David Crosby (RIP) accurate and was surprised that I registered a sensible note at all, versus something sharp or flat. I'd think with practice, one could learn to hit different notes in whatever chords this way.

As the speakers in your guitar arent arranged to physically cancel any forces (If they were mounted magnet end-to-magnet end, say) they may impart into the guitar body, they may just 'shake" it enough to do the same thing in response to a vocal input.
 
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Folded Horn Acoustic Guitar Patent # 10,777,172:

It works, the damn guitar works!!!

I was worried about the acoustic guitar intonation, had a bad neck before (fixed) then a bad nut before (fixed).

Now the neck is dead straight, nut height is a little high, which I like, less distortion on frets, generally harder to play, but not for me.

After a few years, I finally have it right. 4X the acoustic power, really rocks!

The intonation is great, open to twelfth fret, perfect!

I was very worried about feedback, not a problem at all, what a relief!

That said, it is like an acoustic guitar with electric guitar power. If you play a hard open chord and let it ring, it will feedback (power) but only if you let it!

4X times the power lets you play easy, and get a big sound, no need to beat the hell out of the guitar.

The Holy Grail of Acoustic Guitar is not tone, that has been mastered many many decades ago, it is power (volume).

I would like to add effects. I have the Tonewood amp. I will add for an even better experience!

This guitar (acoustic only) is 5 dB less that a standard acoustic guitar, due to less volume in the chamber, always knew this would happen.

With the speakers and horns kicked in, WOW, blows it out of the water, can hit 120 dB.

I have improvement ideas for sure. but the goal id to sell the IP, Gibson? I will try!
 
I would like to add effects.
https://www.ebay.com/itm/155194039163 I've bought from this seller, he's good; he also sells the one I'm using. If you can get it on ebay, you can get it from aliexpress too, cheaper. https://www.aliexpress.us/item/3256804459931558.html

It's a start. Almost "cement half A to half B"...

Add your own class D chip-amp, many, many stereo board level options that'll drive both speakers independently. The power supply; as the preamp runs from a 9V, while the amp runs from a 20V Li-Ion battery pack of some kind. The hardest part will be getting it all physically into the guitar, with the good ergonomics on the player controls and battery replacement.

One reason a drill battery is such a good idea starting out is the charging system is just that for the drill. Messing with such a thing and LiIon batteries is risky from a liability standpoint; people have died already from battery fires due to such charging system malfunction. Leave that to Black & Decker, Coleman-Porter. Yamaha, if they pick up a license.

Congratulations!
 
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Thanks JJ - I am very happy that everything worked out so well, BUT I always want to do better of course. I would really like to get that 5 dB (acoustic only) back, I think it is a big deal for tone. Not so much for volume, as the horns and speakers kill that. My guitar adds so much when cranking it up, just great, but does it sound better than a Taylor or a Martin when played only acoustically, of course not!

Thankfully the horns add a huge low end, and I need it now, really saves me. If this was just the small speakers without horns, it would be toast. When playing the Guild through the horns I almost always had all the bass turned off. Now with the acoustic guitar 5 dB less and not a Taylor or Martin or Guild, I need to turn up the lows, but thankfully the horns, piezo bass and amp bass brings it all back, but I would really like to have it from the acoustic guitar. That said, I am going to blow two holes thru the chamber divider to match the through body holes, but not through the speaker area.

My guitar above the chamber divider is less than 2" and a standard guitar is about 4", so that is the difference, maybe the holes will help because it will greatly increase the size of the standard acoustic guitar chamber above the horns (and through the entire body in those two area only, all horns still covered). Plus I am going to drop the nut/action a little, plenty of room.

Art are you here? Any ideas about a resonant chamber that is 2" thick vs. 4" thick? I know there is a difference, I can hear it.

Also I will seal the chamber divider, after so many things to do, I actually forgot to do that! That will help greatly.

I still need to mount the amp, but it still sounds great and plenty of power. Fitting it is the biggest challenge, but sound is not a problem at all, great!

My light but strong soundboard vibrates like crazy, almost like a drum head, you can feel it, works better than expected! If you purposely let the guitar feedback, you just touch the soundboard, and feel the crazy vibrations suddenly stop and the feedback is gone, so that means it is coming from the piezo pickup. The soundboard vibrates way way more than a standard acoustic guitar. When I touch a standard soundboard, you can feel it vibrate, but barely, so this can work in my favor. That said I want to build a Sitka Spruce soundboard (now that I know how to do it) just to compare and see what happens.

A smacked tuning fork sounds about the same on my guitar sides and a Taylor. On the head of the guitar neck I can barely even hear a Taylor, not sure why. My guitar with smacked tuning fork on the head of the guitar neck rings like a bell, great, but not sure why. The Taylor soundboard really rings out more than mine, so I know I need to improve the acoustic chamber and or soundboard in some way to get that beautiful Taylor sound, before anything hits the horns. I may need to rip the back off my Taylor and build a simplified horn system there, what???!!! This is why my second patent is so critical, it is not as defined, meaning it covers the system generally, so doing something a bit different than mine, but same concept, is covered. Hey it is filed (First Inventor To File), so I am covered.

All dragons have been slayed, but I still want to chase that slightly better acoustic sound, because that of course is the producer, the reproducer is working fantastic! I really think the larger chamber divider (and sealed) is key. I could make the guitar thicker, but that would likely be a dealer killer. It is very comfortable to play now, add another inch it would be dicey, I think I hit the limit there.

I am ahead of the patent office now, still waiting for the second patent. It has been in their office for a year now, they confirmed it was received. The standard wait now (ever since Covid) is 1-1/2 years just to start reviewing. I am getting the feeling this is going to be a life long project! Great for me because I love it, but not so great for selling the IP. I submitted the first patent about June 2019, pre Covid, and it sailed right through.

JJ thanks much for the product info, I will likely spend mucho time testing items like that, and of course I need to crank up the Tonewood amp. I still love your battery idea, will not forget that one. Plus I need to get all new data for this finished guitar in REW. Sorry for rambling on so much, but I am thrilled with progress. When I put that first neck on and it was a piece of ****, and then put the first nut on, and it was a piece of ****, I was like, oh no, I have two strikes on me. :ROFLMAO: Talk about the thrill of victory and the agony of defeat! Joe - Patent # 10,777,172.
 
As you found, the smaller resonant chamber will have less acoustic output, no surprise there- think of what a Gibson 335 sounds like compared to a full depth guitar.
A resonant chamber that is 2" thick vs. 4" thick would need a smaller port diameter to tune to the same frequency. Covering part of the port should lower the resonance, and the acoustical feedback frequency.
 
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Thanks much Art, agree and will try that. I was expecting this, but the good news is my guitar is capable of playing acoustically. Pretty good, but it is meant to play with the electronics of course, and that is where it shines.

JJ has been mentioning many ways to get effects, and I am going try try some of that, now that I have an actual finished guitar to play.

I ran into a friend that is an audio engineer and he asked about my project. When I told him the horns, speakers and amp really rock, he said how is your acoustic guitar intonation. I said thankfully it is finally perfect after some struggle. He said great, that is all you need, you have your product.

My response was that the guitar acoustically is good, but not as good an a Martin or Taylor...and that bothers me.

He said who cares? If your guitar was an acoustic guitar only, then it would be a problem, but you have the folded horns, amp and speakers, that is totally different. He said I will give you some digital small footprint equipment that will let you model any tone you want from your acoustic guitar with correct intonation, THEN send it though the amp speakers and horns. It will sound like anything you want it to. Program in a classic Martin sound, program in an electric guitar sound if you want, anything, the list of different tones is amazing. Plus of course some good EQ, up the lows if needed...

It is similar equipment that Line 6 uses (owned by Yamaha) in their modeling guitars. Anybody familiar with this company and their guitars? How do the different tones sound?

I always had Yamaha on my list of potential buyers, but I did not know they owned Line 6. Maybe they would be the perfect company to buy my IP. Hey, it is worth a try!

I have much work to do on the tone end, and in REW to measure and compare. Please USPTO, hurry up with my patent!
 
So your chamber divider is what, 1/2" thick? Try something thinner, which will give the acoustic chamber more depth and hence, volume. Dont be afraid of metal; Travis and Ovation used it. Plus if it's glued and screwed all around the periphery of all that horn routing; it'll probably be quite stiff even if thin. A sheet of carbon fiber? Masonite? Plexi, or modern day equivalent?

You might want to experiment with different sound hole diamaters as Art suggested; perhaps that gives the tone even if it's not as loud. As your friend says, so what - it's supposed to be an electrified acoustic. They have silent guitars (I have one) so in some cases, the quiet mode is useful.

Or you can forget all that and just make a full solid body electric version with dual humbuckers sunk into a solid wood top, that doubles as the horn chamber cover; think dividing board extended though the acoustic chamber to the top. You'll have to watch the weight of all that wood!
 
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I checked out Line6 (Yamaha) guitar sounds on YouTube. Very innovative guitars, love what they are doing.

It is an electric guitar, basically with a synthesizer, and it can really nail the sound of other electric guitars, great!

Can it nail the sound of an acoustic guitar with this electric guitar? I saw some very talented guys trying to do this, and they were damn impressive. Does it sound like an acoustic guitar? Pretty good I must say, but still not an acoustic guitar. Trying to do that with modeling is very cool, but def not the same.

I even saw a guy that calls them a gimmick, I do not agree with that, they are seriously nice instruments, and they have a large and loyal following.

Have you ever seen the YouTube video with Leo Kottke, Doc Watson and Chet Atkins jamming together in an airport? Now that is how acoustic guitars should sound. I bet they had them out of their cases, tuned and jamming in five minutes. Not a an electrical cord to be seen.

I believe my guitar in that kind of situation would sound like a cannon, and of course would be easier to play, cut down on fret noise and string buzz, even the best get that on acoustic guitars.

I have some new ideas to make the upper chamber larger, I am not going to settle with what I have now. Great with acoustic/electric setup, but still needs that boost for acoustic power and warmth. After all people will not just plug it in and play, they will likely play acoustically first, and first impressions are a big deal.

Right now my upper chamber is approx. 65% in size (volume) of a standard dreadnought guitar. I can get to 85% with this idea, and maybe 97%. Much to test this weekend, stay tuned!
 
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Art - you schooled me about harmonics/overtones at the start of this thread, thank you. I knew about them, but did not appreciate their importance until you told me, and I measured them in REW.

I would really like to hear your opinion regarding undertones. Some online say they don't exist, others say they are there but can't be heard. Andy Powers from Taylor seems to like them, from what I read. Plus this is in the 30-80 Hz range, below the lowest frequency of a guitar, hence undertones!

Personally I know they exist, I can hear them and I can measure them, at least with these horns, not sure about other situations. This is the "through the roof" lows I can hear when I cover my horns, just with music from my iPhone playing (although that includes a bass guitar). I can most certainly hear them when I played my Guild through these beautiful five feet long horns/waveguides. I swear it is some of the best acoustic guitar I ever heard, even with my playing. :ROFLMAO:

Forgive my crude sketching on this REW data, but I think it shows it very clearly, and I hear it!

Now the undertones on a standard acoustic guitar probably can not be heard well. The lowest is at 30 dB, I bet my ears can not hear that.

When the speakers are on and the horns are rocking, the lowest undertone is at 80 dB, easy to hear, even compared to the higher dB of all other frequencies.

Also note the undertones are in the same dB range as the harmonics/overtones, although I know the highs are easier to hear at the same level. I find this to be highly interesting. What do you think? Let me have it! Joe