A step closer for sure - is the "Actual Folded Horn Acoustic Guitar" graph;
Putting the guitar on a bed, tail toward the head of the bed, neck pointed toward the foot, laying the mic on the bed surface about 1M away from the horn mouths would be a good, repeatable setup. I think someone called it a "bedplane" vs ("groundplane") measurement setup to look for the actual FR of your horns.
The "Actual Folded Horn Acoustic Guitar" graph looks like a driver on a test baffle in an anechoic chamber; (Which, if so, I'd find kinda hard to believe and there'd be nothing to help you with, as it's just about perfect as-is. Hence my doubts; but, you know miracles abound!)
- with the random pink noise from REW playing through your dedicated amplifier, then connected to the speakers inside your guitar?
- with the tone controls set flat and playing at a moderate (but well above any background noise) sound level?
- with the noise solely coming out the two horn mouths pointed toward your measurement microphone, about 1 meter away?
Putting the guitar on a bed, tail toward the head of the bed, neck pointed toward the foot, laying the mic on the bed surface about 1M away from the horn mouths would be a good, repeatable setup. I think someone called it a "bedplane" vs ("groundplane") measurement setup to look for the actual FR of your horns.
The "Actual Folded Horn Acoustic Guitar" graph looks like a driver on a test baffle in an anechoic chamber; (Which, if so, I'd find kinda hard to believe and there'd be nothing to help you with, as it's just about perfect as-is. Hence my doubts; but, you know miracles abound!)
JJ,
All Joe's graphs are screen captures of noise or music, random. The "Actual Folded Horn Acoustic Guitar" graph has 10dB per line increments (and only extends to 3kHz), there are around 30dB level deviations between 120 and 800Hz at that particular capture moment.
The REW toolbar "measure" button allows measurement sweeps to be saved, which would allow some useful comparisons to be made, as shown in the Help manual:
If Joe used sweep measurements, he could learn what the folded horn response actually does.
Art
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Sheesh, I sure didnt pay attention. I'm hoping the pink noise response can show something leading to discussion, then a swept test for more accuracy on an instrument making sine tones - a lot. That's more complicated to do imho, as you need the gating channel connection hooked up so REW can discount the room reverb.
I mentioned before that I need zero bass turned up from the amp, I am getting it all from the waveguide/horn itself, without any distortion. I mean I play thru the uncovered waveguides with the amp bass up to 10, and there is almost no bass at all. Then I close the waveguides, and the bass goes through the roof, distorted! Then I turn the amp bass to zero, and there is huge bass through the waveguides, zero distortion, sounds great.
That said, I always had the highs/mid on anywhere from 3 to 7, experimented, liked 3 better, still highs, less distortion, but never tried ALL the tone controls at zero. When I did this, I was surprised that the bass of course was great, but also the mids and highs still sounded great thru the waveguides, distortion gone, cleanest I ever heard, AND it let me turn volume and master volume up to 10 with no distortion, and just a little amount of feedback, but only if I took my fingers off the strings. Total control, sustain for a held open chord was 20 seconds. A beast!
Then I played a standard acoustic guitar by itself, was quite frankly disappointing, never felt that way before, but by comparison, WOW. Anyway I finally have the dovetail cut in the body after waiting for machine time. Now the ball is in my court to assemble an fit! Comments welcome and thanks! Joe
That said, I always had the highs/mid on anywhere from 3 to 7, experimented, liked 3 better, still highs, less distortion, but never tried ALL the tone controls at zero. When I did this, I was surprised that the bass of course was great, but also the mids and highs still sounded great thru the waveguides, distortion gone, cleanest I ever heard, AND it let me turn volume and master volume up to 10 with no distortion, and just a little amount of feedback, but only if I took my fingers off the strings. Total control, sustain for a held open chord was 20 seconds. A beast!
Then I played a standard acoustic guitar by itself, was quite frankly disappointing, never felt that way before, but by comparison, WOW. Anyway I finally have the dovetail cut in the body after waiting for machine time. Now the ball is in my court to assemble an fit! Comments welcome and thanks! Joe
Horns are so clean, low distortion, I turn up mid/high on amp just a little to get that, but not too much. Neck fits! CNC machines
are literally accurate to 1/5 of a human hair thickness (.001"). Boy does that change everything, fits are incredible. Still needs hand work!
The human touch will never go away, ever. Check out the attachments, Art I need help for sweeps! Thanks! Joe
are literally accurate to 1/5 of a human hair thickness (.001"). Boy does that change everything, fits are incredible. Still needs hand work!
The human touch will never go away, ever. Check out the attachments, Art I need help for sweeps! Thanks! Joe
Joe,
The fret board inlays look pretty!
Amir wrote two tutorials to help you with REW:
https://www.audiosciencereview.com/...om-measurement-tutorial-for-dummies-part-1.4/
https://www.audiosciencereview.com/...om-measurement-tutorial-for-dummies-part-2.5/
The fret board inlays look pretty!
Amir wrote two tutorials to help you with REW:
https://www.audiosciencereview.com/...om-measurement-tutorial-for-dummies-part-1.4/
https://www.audiosciencereview.com/...om-measurement-tutorial-for-dummies-part-2.5/
Though well executed, I don't care much for the Specimen Horn aesthetic, and an upfiring midbass horn with a 4" fullrange on the floor would not be something I'd want to listen to for long, regardless of it's cost.
I'm obviously not Ian's target audience
Hello all - updated technical and marketing plan attached, as well as Folded Horn Acoustic Guitar U.S. Patent. Please ignore the tape on the guitar, it is not complete yet. It is also obviously unfinished, hope it looks better with stain and hand polishing. Still a work in progress, I am sure there are some corrections needed in the plan, and of course with the build. Please point them out if you would be so kind, especially Art and JJ! Our critics are our friends, for they show us our faults (Benjamin Franklin).
My wish is to design and build a guitar that sounds great - supporting data and ears required! If it sounds good, it is good (Duke Ellington) including:
Improved volume (check- 4X as loud), play easier with a bigger sound and less distortion (check), tone as good or at least close to the beautiful tone of an acoustic guitar (working on it). No external source required, unplugged (check). Charge at night like your iPhone (check). Soothes the soul (check). Thanks! Joe
My wish is to design and build a guitar that sounds great - supporting data and ears required! If it sounds good, it is good (Duke Ellington) including:
Improved volume (check- 4X as loud), play easier with a bigger sound and less distortion (check), tone as good or at least close to the beautiful tone of an acoustic guitar (working on it). No external source required, unplugged (check). Charge at night like your iPhone (check). Soothes the soul (check). Thanks! Joe
Joe,
"NOTE! Since my (folded horn) guitar is not finished yet, I play another guitar through
it for now."
You have still not verified any volume or distortion claim or ease of play, or "tone as good or at least close to the beautiful tone of an acoustic guitar". Nor have you verified operation at a level 20dB above an acoustic guitar.
As built, the magnet side of the drivers loads into a Helmholtz resonator exiting through the sound hole between the bridge and neck, the cone side of the driver through the folded quarter wave pipes.
Your PowerPoint Presentation claim that "the sound from the back of the speaker has no interference with the front of the speaker" is unverified.
If you test the speaker enclosure, you will find the claim untrue, easily verified by phase and frequency response.
The patent makes reference to using a microphone, rather than a pickup.
You will also find that 20dB SPL gain over a standard acoustic guitar using an internally mounted microphone with internal speakers is not possible.
Art
Thank you Art, I knew you would come through, you always do. Let's see where I can defend myself, and also where I realize I need improvements:
You are correct that my Patent references a microphone, you are also correct (and I have learned through testing) that 20 dB SPL gain using a a mic and speakers is not possible. This is my biggest regret on the Patent. The good news is I have tested a piezo pickup, and it works very well, without feedback. I does not sound quite as good as a microphone, but it is close. They only way I could get it to feedback is if I mounted it directly on top of the speakers, which I am not doing, it is in the soundboard. Even on top of the speaker, but about 3" away it would not feedback, so I know the soundboard is safe, since a piezo works based on pressure in the material itself. I can still use a mic with a piezo, but anything turned up on the mic above 3 is toast. Having a little mic helps for sure, but it can not be the main source. The other change I needed to make on the patent was using waveguides instead of horns. I wrote and submitted another patent called Acoustic Waveguide Guitar. It is very similar, but has those two changes, so the guitar will be covered by two patents. I know this works, because software Patent Attorneys do this all the time with small changes, and they are accepted. This patent is not granted yet, so I can not share it, but I am the FITF (first inventor to file) so I am safe. Many people think the patent granted date is the most important target, not true, first to file is. Congress wrote this into law I think about ten years ago. Plus patent trolls do this all the time, just a small change and they get a patent and rip people off, or they find a product that works and is not patented yet, they file first and win, big unintentional problem that needs to be solved. That is why I did not release any of my information until the patent was filed, and also granted.
I can not verify tone is as good or close to an acoustic guitar, I said I am working on that, so I have not claimed this yet, but I am getting good results with the correct tone settings from the preamp on the Fishman piezo pickup and also on the amp, stay tuned (do not use cheap Chinese electronics, they are junk).
I guarantee the distortion is reduced. When not using the horns the bass needs to be up to 10 to be heard, clearly more distortion. When I use the horns, they provide so much bass, I can turn the bass to 2 or even off, clearly less distortion with efficient horns, I just have not measured it yet in REW, but I will. Easily one of the greatest benefits of this guitar. I hate when people beat the hell out of an acoustic guitar to be heard, clearly distorted, you don't need to do it on this guitar, with a 20 dB increase in volume (have data, measured in REW and with a dB meter). The louder the volume, the easier you can play, the less distortion. I know it is true, I hear it every time I play this, a win!
Ok no interference from the front and back is a stretch, I should say minimal. I have them separated likely as much as possible in this design, so good, but I will consider taking this out of the specs, because I have not proven it, I will try your suggestion.
What do you think? Let me have it, and thank you much as always Art, I am very grateful for your involvement in this project. I think maybe you are the DIY Audio Godfather, I see you on other threads. I have not had enough time to view many, but I am starting to do more of that, great way to learn. Thank you! Joe
You are correct that my Patent references a microphone, you are also correct (and I have learned through testing) that 20 dB SPL gain using a a mic and speakers is not possible. This is my biggest regret on the Patent. The good news is I have tested a piezo pickup, and it works very well, without feedback. I does not sound quite as good as a microphone, but it is close. They only way I could get it to feedback is if I mounted it directly on top of the speakers, which I am not doing, it is in the soundboard. Even on top of the speaker, but about 3" away it would not feedback, so I know the soundboard is safe, since a piezo works based on pressure in the material itself. I can still use a mic with a piezo, but anything turned up on the mic above 3 is toast. Having a little mic helps for sure, but it can not be the main source. The other change I needed to make on the patent was using waveguides instead of horns. I wrote and submitted another patent called Acoustic Waveguide Guitar. It is very similar, but has those two changes, so the guitar will be covered by two patents. I know this works, because software Patent Attorneys do this all the time with small changes, and they are accepted. This patent is not granted yet, so I can not share it, but I am the FITF (first inventor to file) so I am safe. Many people think the patent granted date is the most important target, not true, first to file is. Congress wrote this into law I think about ten years ago. Plus patent trolls do this all the time, just a small change and they get a patent and rip people off, or they find a product that works and is not patented yet, they file first and win, big unintentional problem that needs to be solved. That is why I did not release any of my information until the patent was filed, and also granted.
I can not verify tone is as good or close to an acoustic guitar, I said I am working on that, so I have not claimed this yet, but I am getting good results with the correct tone settings from the preamp on the Fishman piezo pickup and also on the amp, stay tuned (do not use cheap Chinese electronics, they are junk).
I guarantee the distortion is reduced. When not using the horns the bass needs to be up to 10 to be heard, clearly more distortion. When I use the horns, they provide so much bass, I can turn the bass to 2 or even off, clearly less distortion with efficient horns, I just have not measured it yet in REW, but I will. Easily one of the greatest benefits of this guitar. I hate when people beat the hell out of an acoustic guitar to be heard, clearly distorted, you don't need to do it on this guitar, with a 20 dB increase in volume (have data, measured in REW and with a dB meter). The louder the volume, the easier you can play, the less distortion. I know it is true, I hear it every time I play this, a win!
Ok no interference from the front and back is a stretch, I should say minimal. I have them separated likely as much as possible in this design, so good, but I will consider taking this out of the specs, because I have not proven it, I will try your suggestion.
What do you think? Let me have it, and thank you much as always Art, I am very grateful for your involvement in this project. I think maybe you are the DIY Audio Godfather, I see you on other threads. I have not had enough time to view many, but I am starting to do more of that, great way to learn. Thank you! Joe
Still having trouble envisioning how this goes together. The left hand piece drops inside the guitar "frame", sealing the waveguides and leaving a space from its plane to the right hand piece, the guitar "spruce top" surface. So the rear of the two drivers exits through the cutout, into that space between the two planes, then comes out the sound hole. I assume the back plate is sealed; the two chambers between the speakers and the neck are unused, sealed space - acoustically. Is that where the amplifier and batteries go?