Resotune II

GroupDIY Audio Forum

Help Support GroupDIY Audio Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Does that mean that soon the schematics will be added to the forum and the community will be able to make it?
I am tempted because there are a few clever features to the circuit I wouldn't mind showing off, but right now my old PC that had my old working copy of Eagle (a licensed seat) is refusing to boot up. I haven't scrapped the old PC yet but don't feel lucky about recovering that old hard drive. I have read about a strategy to install a working hard drive into the PC so it can boot up and then recognize that faulty drive as just another drive. Or maybe I need to install that faulty drive into a a working PC? I am not aggressively pursuing this.

==

The real IP associated with RESOTUNE is the thousands of lines of microcode. The PC that code is in still works. I don't think I could easily explain some of the code routines. One IMO clever algo uses synchronous rectification to allow me perform a frequency sweep with stimulus tone containing the same note in 3 different octaves, then figuring out a way to measure the levels of the individual octave spaced notes.

As clever as that is, if I was starting a scratch design today I would use DSP to perform a FFT . I already experimented a few years ago with code running on a DSPic. I made a stimulus signal with a half dozen or more spaced tones, and then performed a FFT to read, rinse and repeat to quickly zero in on important drumhead resonances. This was much faster than the RESOTUNE frequency sweep.

This really isn't what the patented invention is (was). I have since stopped paying maintenance fees on that patent (6,925,880 Roberts August 9, 2005) so it is now public domain. The secret sauce algo that allows RESOTUNE to precisely clear drumheads, is exciting the drumhead with loudspeakers to vibrate at the first overtone. Then measure the return signal with a microphone. By comparing the phase of the measured (return) resonance compared to the signal I am driving the drumhead with I can impute factors about the lug tension. The magic that allows me to concisely measure one lug at a time in such a way that the adjustment converge (not interact) is the use of two loudspeakers bracketing (on either side of) the lug being measured/adjusted. The two speakers acoustically couple to the drumhead and isolate the contribution of the one lug being measured from all others. Using this strategy the lug tension can be precisely matched ignoring mechanical differences.

Technically the acoustic coupling of the two speakers alters the effective mass of the drum head very slightly altering the pitch of the natural resonance, this pitch error is inconsequential compared to the benefit of precision "clearing" (making the lugs match each other).

Years ago I tried to license this to Yamaha and they weren't interested. Drummers want a cheap smart phone ap, not a clunky two speaker gadget. I could make RESOTUNE faster and better, but not smaller and cheaper. There is probably a small market for a high end DSP version, but I am old and tired.

JR
 
How long should I support my drum tuner website? about drums I invested many hours sharing what I learned about drums.

My web host was charging me extra to support an obsolete revision of PHP so today I just upgraded to the most recent version of wordpress to support a current supported version of PHP so save the extra fees. But a year from now I could have to do the same dance.

My personal vanity website was written using an old PC software program that became inaccessible when the hard drive on one of my PCs died.

What I may have to do is capture and redo that vanity website, maybe save some of the content from my drum tuner website that is worth saving, or just let it fade away...

JR
 
I say do what whatever reduces tediousness / improves quality of life, John. Also tell the tired voice it's no good, and to go bother someone else.
 
I say do what whatever reduces tediousness / improves quality of life, John. Also tell the tired voice it's no good, and to go bother someone else.
I guess I could stop being a moderator... that can get pretty tedious.

Tired voice? Old and tired seems like a fair description for how I feel.

Go bother somebody else? I'll think about it.

JR
 
I'm in a 'life is precious, fragile, and short' sort of head space.

A few posts ago in this thread, you mentioned being tired as the reason for not improving Rezotune.
What I meant was, if you think the tiredness is simply due to getting older, reacting to it by doing less probably won't make the tiredness go away.
In fact, all it may do is speed up the process of eventually... doing nothing.

If you're legitimately exhausted, well then for goodness sake, drop some of the spinning plates.
Everyone forgives you in advance, for sake of your best life ahead. :)
 
Last edited:
Don't mean to sound cliché, or overly simplistic. I'm in a 'life is precious, fragile, and short' sort of head space.
life gets shorter the closer to the end you are at.
In your post before the last one, you mentioned being tired as the reason for not improving Rezotune.
Tired of the market response from drummers.
If you think the tiredness is simply due to getting older, I say reject that voice. If you're legitimately exhausted...well then for goodness sake, drop some of the spinning plates.
I already have/am
Everyone forgives you in advance, for sake of your best life ahead. :)
I have enjoyed a good life and continue to manage pretty well... I have mixed results getting my raised bed garden started this year (the pepper plants are slow to prosper ).

My fig tree still hasn't bounced back from the late hard freeze.

I'll be OK, do not worry about me. Me saying that I am old and tired, is a standard response.

JR
 
Programing a smart phone to do resotune sounds like a logical next step
A simple external speaker box with a mic which could plug into the phones headset jack might be all thats needed in terms of hardware .
The app could be made available for free and you could make your money back off selling the ultra simple interface box .
 
Same here. The habaneros especially are extremely slow to get going. Tomatoes are looking pretty good though.
yup... I have 4 tomato plants already thriving, my peppers are puny.
True. Does the math require two speakers? Specific geometry? Digitize the user interface, have it pair to hardware.
To be able to adjust individual lugs (for clear) that will converge to a single optimal tuning requires two speakers that bracket either side of the lug being adjusted. I could make it work with only one speaker but there was too much interaction between lugs so it did not quickly converge, kind of like manual tuning requires following a symmetrical pattern.

That would just make it more expensive.
Programing a smart phone to do resotune sounds like a logical next step
A simple external speaker box with a mic which could plug into the phones headset jack might be all thats needed in terms of hardware .
The app could be made available for free and you could make your money back off selling the ultra simple interface box .
??? that reminds me of back when I was still working trade shows and customers would tell me "all I need to do is" :rolleyes:

I stopped paying maintenance on my patent so you are free to take it and run with your idea. ;)

FWIW a friend of mine developed a smart phone app (more than a decade ago) basically what I call a "note sniffer" that works after a fashion but not as concisely as my hardware approach. I was going to promote his smart phone app on my website because I did not consider it competition for mine. But he was put out of business by threat of lawsuit from the pukes behind tune-bot. They had a patent and claimed that he infringed on their patent. In my judgement he didn't infringe but patent lawsuits are a sport for people with deep pockets. He didn't have the money to fight at that level.

JR
 
I havent the first clue about making mobile phone apps ,
There is lots of youngsters out there doing computer science though ,
Often they have to produce a mobile phone app as part of their course work ,
If you found the right person , who was a musician and had the math and programing skills to do it , it might not be that big a job .

The measurement unit with the mic and speakers only needs audio input and output , its doesnt need to communicate to the software other than audio signals .
 
I havent the first clue about making mobile phone apps ,
There is lots of youngsters out there doing computer science though ,
Often they have to produce a mobile phone app as part of their course work ,
If you found the right person , who was a musician and had the math and programing skills to do it , it might not be that big a job .

The measurement unit with the mic and speakers only needs audio input and output , its doesnt need to communicate to the software other than audio signals .
That sounds pretty easy... 🤔

I wrote several thousand lines of microcode to make mine work effectively, but I am self taught.
====

While not very fancy you could make a crude drum tuning aid out of one of those pocket recorders. Record the drum sound while tapping next to the first lug, then adjust all the other lugs to make the same pitch when tapped as the pocket recorder sample playback.

It's harder to make your smart phone app read and display the note pitch. There is some note bend when you first hit the drum, and drums can sound multiple different resonances.
circle21.gif


Budget some time to figure out how to filter the wheat from the chaff.

The lads have been working on these for a couple decades so by now smart phone apps should be dirt cheap. Note sniffers can't really clear your drum, but can get you in the ball park.

JR
 
I am tempted because there are a few clever features to the circuit I wouldn't mind showing off, but right now my old PC that had my old working copy of Eagle (a licensed seat) is refusing to boot up. I haven't scrapped the old PC yet but don't feel lucky about recovering that old hard drive. I have read about a strategy to install a working hard drive into the PC so it can boot up and then recognize that faulty drive as just another drive. Or maybe I need to install that faulty drive into a a working PC? I am not aggressively pursuing this.

==

The real IP associated with RESOTUNE is the thousands of lines of microcode. The PC that code is in still works. I don't think I could easily explain some of the code routines. One IMO clever algo uses synchronous rectification to allow me perform a frequency sweep with stimulus tone containing the same note in 3 different octaves, then figuring out a way to measure the levels of the individual octave spaced notes.

As clever as that is, if I was starting a scratch design today I would use DSP to perform a FFT . I already experimented a few years ago with code running on a DSPic. I made a stimulus signal with a half dozen or more spaced tones, and then performed a FFT to read, rinse and repeat to quickly zero in on important drumhead resonances. This was much faster than the RESOTUNE frequency sweep.

This really isn't what the patented invention is (was). I have since stopped paying maintenance fees on that patent (6,925,880 Roberts August 9, 2005) so it is now public domain. The secret sauce algo that allows RESOTUNE to precisely clear drumheads, is exciting the drumhead with loudspeakers to vibrate at the first overtone. Then measure the return signal with a microphone. By comparing the phase of the measured (return) resonance compared to the signal I am driving the drumhead with I can impute factors about the lug tension. The magic that allows me to concisely measure one lug at a time in such a way that the adjustment converge (not interact) is the use of two loudspeakers bracketing (on either side of) the lug being measured/adjusted. The two speakers acoustically couple to the drumhead and isolate the contribution of the one lug being measured from all others. Using this strategy the lug tension can be precisely matched ignoring mechanical differences.

Technically the acoustic coupling of the two speakers alters the effective mass of the drum head very slightly altering the pitch of the natural resonance, this pitch error is inconsequential compared to the benefit of precision "clearing" (making the lugs match each other).

Years ago I tried to license this to Yamaha and they weren't interested. Drummers want a cheap smart phone ap, not a clunky two speaker gadget. I could make RESOTUNE faster and better, but not smaller and cheaper. There is probably a small market for a high end DSP version, but I am old and tired.

JR
I honestly don't know how (and I truly mean this as a compliment) did you manage all of that without knowledge of advanced math or a formal education. I know some people are just clever, but I, personally, am very square and really need to dive into the books.
 
A box with a battery powered amp , two speakers , a mic and a mini USB headset adapter ,
it doesnt need a brain , youre smart phone or pc has the requisite DSP built in ,

Maybe a re-focus on the patent applied for ?
the devil is in the detail ,as we say here ,
 
A box with a battery powered amp , two speakers , a mic and a mini USB headset adapter ,
it doesnt need a brain , youre smart phone or pc has the requisite DSP built in ,

Maybe a re-focus on the patent applied for ?
the devil is in the detail ,as we say here ,
the details are the brain of course, the code in the DSP, the rest is off-the-shelf
 
Back
Top