Folded Horn Acoustic Guitar Patent # 10,777,172

Joe K

Member
Paid Member
2021-08-14 12:12 am
Indianapolis, IN.
Yes the board I am standing on closes the waveguide, and yes I also have a solid version as well (no hole over the speakers), experimenting with both.
Obviously different results based on capturing sound from the back of the speaker. Closed has more bass, which honestly I don't need, because I am getting so much from the waveguides. Open is noticeably loader (can't remember dB difference). The soundboard itself will also have a version with standard hole, and no hole. Amazing how trying different combinations of both changes the volume, tone, and which frequencies levels are favored.

Again the chamber divider must be fully closed and pressed hard against the body to get great results. I am only getting some feedback from a mic, and also a little with pressure transducers when I mount them within 4" of the speakers. That is where they pickup too much vibration and feedback, beyond that no feedback. The under saddle piezo zero feedback, at least with another guitar, so not a great test, but encouraging. The "chamber divider" I am standing on is very easy to make, so I can try many different types. 1/4" Baltic Birch, just cut/sand the outside/inside shapes at home.

I want to screw this and the top soundboard onto the guitar, no glue, so they can be removed easily. This is where the banjo construction influences me, and also the soundboard/skin that moves so easily on a banjo.

Since the maple is 1/4" thick, I can easily use #5-40 stainless steel screws. Brass looks better, but not strong enough. Dovetail programming should be complete this week, pretty easy, then of course waiting for machine time at work to cut it. After that I can assemble/fit.

I don't know why I decided to stand on the chamber divider, but it is pretty amazing to feel the vibration in your legs. I know not useful, but fun! I keep telling myself bottom rigid as possible so it rings like a bell, and top as thin/strong as possible so it moves like a driver cone. Have you checked out Electrophonic Innovations with the amp/speaker in an electric guitar? What do you think? I believe the amp is rated at less than 20 watts. Thanks JJ!
 

Joe K

Member
Paid Member
2021-08-14 12:12 am
Indianapolis, IN.
I was wondering how it could get any volume from those speakers with almost no enclosure to speak of really.
In some ways like the Fender Acoustasonic, which also has a small acoustic chamber, also low volume (but no speaker).

I don't see the point in making guitars that are not much louder than an acoustic guitar. You will just have to play it hard to keep up
with other instruments, then distortion happens and tone goes downhill. As I said before, when my waveguides are not covered,
the volume increase is very minimal, so Art your comment about that guitar not being much louder than an Acoustic Guitar may
very well be true, I will check it out. I still like the guitar, and their concept is good, may need some improvement, I will buy one and test.

They also get good reviews, but I wonder from who, because every once in a while they get a review from a guy that says it sounds terrible,
does he know something, or have a real ear for music, that some of the others do not, I can only wonder. I am convinced if you do not put
serious waveguides or serious horns (or a combination of the two) :):unsure: inside the guitar and make it truly like a fine speaker cabinet,
you will just have a few small speakers mounted in a piece of wood, big deal. Guitars like that have been around for decades.
Oh yeah, and will my instrument need improvement? Of course it will!

Electric guitars today are great, and have been for a long time. The Acoustic Guitar sounds great, but needs improvement.
It can be done, and not throw the baby out with the bath water, keep all the good parts (tonewood, body size, beautiful tone, portability).
Add some damn volume, a very serious improvement. Just pick it up anywhere and play, lets rock!
 
Have you checked out Electrophonic Innovations with the amp/speaker in an electric guitar? What do you think?
I did look at their website - thanks for letting me know. Of course, I cant tell if the second grille is a port or another speaker. I suspect it wont hold a candle to your invention when finished. You should ask them if they'd be interested in a license ;')
 

Joe K

Member
Paid Member
2021-08-14 12:12 am
Indianapolis, IN.
I think they might have two speakers, but thank you JJ for your support! I gave them my info on their website contact page,
we shall see if they respond. I am interested in a license deal, and other options. I really can't wait until I get this guitar assembled,
then I will have a real product. My intention is to show it on YouTube and also a website. I keep telling myself, patience. patience...:violin:
 
Of course, I cant tell if the second grille is a port or another speaker.
It's a second speaker, the guitar has stereo effects. The combined speaker sensitivity for the 3.5" and 2"(guestimated sizes) is probably around 90dB 1w/1m sensitivity, so around 103 dB at one meter with 18 watts "full tilt". In the Electrophonic video "Loud is Relative. Dillos are fun", with a Guitarmadillo playing with drums around 10 feet away, the heavily distorted guitar sounds about as loud as the kick drum when the camera/mic is a few feet from the guitar. If the guitar was played clean, the average level would sound about half as loud, -10dB.

Joe's far larger (and heavier..) horn properly executed with the correct drivers potentially could have peaks with sensitivity of near 105dB 1w/1m, though his comparison of the guitar horn only being +5dB over the Bose radio (roughly 85 dB 1w/1m) and the horn's lack of high frequency output does not sound encouraging.

Art
 

Joe K

Member
Paid Member
2021-08-14 12:12 am
Indianapolis, IN.
"does not sound encouraging" always breaks my heart Art :ROFLMAO:. That said I did finally load REW, looks great, so maybe I can come up with
some more accurate data. The Bose and my guitar are WAY loader than a standard acoustic guitar, and maybe about the same as the
Electrophonic guitar, which is 18 watts as you note. My amp is 30 watts plugged in, which I do not want to do, so only 20 watts with batteries.
The speakers are 20 watts each. Sorry about the "WAY loader" subjective analysis for now, will improve!

While the waveguides/horns provide great lows, I agree more mid/highs are needed or course. I still do not have the full guitar, so when the light
yet strong Baltic Birch soundboard is added, I am hoping it will provide more mid/highs purely acoustically, and also though the piezo pickup.
I can bend that soundboard so far with my hands it is incredible. If I tried to move a Sitka Spruce soundboard like that, it snaps like a twig.
I love Sitka Spruce soundboards, but hope for more volume with my soundboard concept.

I like your comment about my larger waveguides/horns. Since I have the room, I have been considering adding two more speakers. Maybe two tweeters.
I have room to add them in two areas, and they can be mounted similar to the 3" full range speakers, see attachment. Any suggestions for locations and
why Art, JJ and others? Thank you! Joe
 

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