A Decibel Meter as a Free Speed Meter?

[p1n9183]

20 hours ago, iacas said:

So bad, I'm not going to spend the ten minutes it would take to do such a thing, because I know what the results would be.

An you still took several minutes to write several posts and talk to sound engineers. I appreciate that you did!

21 hours ago, iacas said:

• temperature
• distance of max clubhead speed from the microphone
• angle (both axes) to the microphone
• clubface orientation (a face open or closed will change the frequency)
• location of the max clubhead speed (reaching peak speed at the same exact place)
• everything in the vicinity, including the shoes and clothes you're wearing, the surface you're on, etc. ideally with all of them producing virtually no noise even when moving.

 So they basically tell you is possible but you need to be very restrictive. The same thing I found on my research. 

Temperature: is not going to change much between swing A and swing B.
Distance of max club head: even the PRGR take the fastest speed recorded, not the speed at the ball. But this could be diminish by swinging several times each swing and average the results. 
Angles: also PRGR returns less speed swinging on a certain degree. 
Clubface orientation: it is also an issue with launch monitors that are not reading the center of the mass of the club. You can have a lot more club speed if your face rotation is higher and your lunch monitor is reading the toe of the club.
"Other stuff in the room": are the same from swing A to B, or you can just swing naked! haha 

21 hours ago, GolfLug said:

He said he installed a free decibel app on his phone. He himself has a PRGR apparently but if the idea had merit, others could benefit.

This is the main idea, I have a PRGR and Skytrak. There are plenty of people, more here in Argentina, that can't afford a launch monitor. Also wanted to share the idea and let it be challenged by others. I don't mind been wrong, is part of experimenting. 

20 hours ago, GolfLug said:

I would have thought that would be the first thing to do if to see if this had merit. Maybe he has.. @p1n9183?

I did and all the swings were close to 85 dbs, me swinging at 90 m/h. But I don't mind doing a proper test later in the afternoon writing down the results. I need to find and app that also have frequencies in order to test both. 

 

[billchao]

12 minutes ago, p1n9183 said:

Temperature: is not going to change much between swing A and swing B.

But it will change from session to session, from one person’s location to the next, etc. If your goal is to figure out X db = Y mph in swing speed to share with others, that matters.

[iacas]

43 minutes ago, p1n9183 said:

An you still took several minutes to write several posts and talk to sound engineers. I appreciate that you did!

You could have saved us all some time by realizing I tend to know what I'm talking about when it comes to science and tech. 😛 

43 minutes ago, p1n9183 said:

So they basically tell you is possible but you need to be very restrictive. The same thing I found on my research.

What?

The only way they would imply that it would be "possible" is if you were able to spend six figures (minimum) AND that doesn't include the swing robot that could reach peak speed at the same exact location every time.

No, they didn't say it was possible for someone like you to do anything remotely good.

43 minutes ago, p1n9183 said:

Temperature: is not going to change much between swing A and swing B.

Session to session.

43 minutes ago, p1n9183 said:

Distance of max club head: even the PRGR take the fastest speed recorded, not the speed at the ball. But this could be diminish by swinging several times each swing and average the results.

The PRGR doesn't work the same way - it samples the speed, from behind (inline with the direction of travel) with radar, and takes the highest number it registers. The distance from the PRGR isn't super relevant.

43 minutes ago, p1n9183 said:

Angles: also PRGR returns less speed swinging on a certain degree.

Clubface orientation: it is also an issue with launch monitors that are not reading the center of the mass of the club.

You're not reading. Or understanding. No to both.

The former is because of the microphones, and the latter is because a clubhead swing more closed versus more open will have a different air flow and thus a different pitch and volume. Clubheads are not symmetrical.

43 minutes ago, p1n9183 said:

"Other stuff in the room": are the same from swing A to B, or you can just swing naked! haha 

You're missing the point. How reflective some of that stuff is could matter. The sounds it generates to background noise could matter.

43 minutes ago, p1n9183 said:

I did and all the swings were close to 85 dbs, me swinging at 90 m/h. But I don't mind doing a proper test later in the afternoon writing down the results. I need to find and app that also have frequencies in order to test both.

85 dBs is generally considered ear-injuring volume.

You don't "need to find an app" because this will not work at all.

[GolfLug]

Decibels is sound 'pressure' not wave frequency. From that perspective a SGI Iron will have very different pressure wave than a blade even with the same speed and other variables considered equal. Additionally, since your phone will not be in direct path the turbulence difference (which generates the sound 'pressure) will have much lesser variance. In other words you will have convergence at one particular speed. Maybe it's this 90MPH speed with your 6i. But I doubt you will have proportional deviation above or below the speed to give you anything will reliability. 

2 hours ago, p1n9183 said:

I did and all the swings were close to 85 dbs, me swinging at 90 m/h. But I don't mind doing a proper test later in the afternoon writing down the results. I need to find and app that also have frequencies in order to test both. 

And other speeds? 80, 90? 

[p1n9183]

Here are the numbers of the test I just finished.
Firstly I tested the app Spectroid were you can messure Hz and Db. Must admit that frecuencies were all over the place and only after 5 swings I switched to another app. Decibels were not normally messured so it was useless info. 

Then I downloaded a basic decibel meter to repet the test I did earlier in the week. It was the "Sound Analyzer app" and I made 20 swings with my 6 iron. I put a coin in the corner of a tile on the floor, the PRGR 5 feet behind away from the path of the swing and half foot away from the coin (away from me) I set the phone with the decibel metter app and I swan away from the PRGR and parallel to the phone. This are both readings. 

I ordered the speed from "slow" to "fast" and inserted a graph to see if there is any correlation between the speed and the decibels. 

As spected on lower swing speeds the ambience sound was even louder than the swoosh of the club so the method was usless. But at higher speeds, beginning at around 60 m/h, it was easy to see that there was a relationship between both. They weren't growing at the same pace but it was proportional.

At least for me, for a free app in an old smartphone it seams pretty usefull to know if swing A is faster than swing B in a particular practice session. When you want more speed, all you want to know is if your new move or swing though or technical change is going to give you more or less speed, looking at the decibels is really easy to see that and you don't need to spend money on launch monitors. 
Of course, if you want someting that can compare your speed from place to place, session to session or club to club then you don't have much choice than go and get the launch monitor you can afford. 

Bonus: Linear regresion of both variables.  Y: db, X: m/h

Edited September 27, 2024 by p1n9183

[GolfLug]

Good stuff man. Gage R&R just too low for the purpose though. A for effort and original thought for sure. 

[p1n9183]

 

On 9/27/2024 at 9:58 PM, GolfLug said:

Good stuff man. Gage R&R just too low for the purpose though. A for effort and original thought for sure. 

Thanks! it was a fun experiment and I hope is going to be useful for people that like to go down the rabbit hole like i do but can't afford a launch monitor or even a cheap speed meter.

Of course I'm glad the results were positive, even better than I spected, but it is funny to see that only you took the time to post after the results were given, the only one in the thread that was open minded about the idea. The other posters that daily brought down the idea without proper arguments or proof, disappeared after been confronted with actual data. Maybe they are testing this by themselves and are in shock that they are getting the same results as me!   

 

[iacas]

48 minutes ago, p1n9183 said:

The other posters that daily brought down the idea without proper arguments or proof, disappeared after been confronted with actual data.

Uh, that's not what happened. I'm highly dubious about how your results would work going forward, you showed nothing about your setup, etc.

I trust the physics (your 3 dB over a meter is off substantially) and sound engineers over claimed "good" results.

[Ty_Webb]

On 9/26/2024 at 8:27 PM, p1n9183 said:

Here are the numbers of the test I just finished.
Firstly I tested the app Spectroid were you can messure Hz and Db. Must admit that frecuencies were all over the place and only after 5 swings I switched to another app. Decibels were not normally messured so it was useless info. 

Then I downloaded a basic decibel meter to repet the test I did earlier in the week. It was the "Sound Analyzer app" and I made 20 swings with my 6 iron. I put a coin in the corner of a tile on the floor, the PRGR 5 feet behind away from the path of the swing and half foot away from the coin (away from me) I set the phone with the decibel metter app and I swan away from the PRGR and parallel to the phone. This are both readings. 

I ordered the speed from "slow" to "fast" and inserted a graph to see if there is any correlation between the speed and the decibels. 

As spected on lower swing speeds the ambience sound was even louder than the swoosh of the club so the method was usless. But at higher speeds, beginning at around 60 m/h, it was easy to see that there was a relationship between both. They weren't growing at the same pace but it was proportional.

At least for me, for a free app in an old smartphone it seams pretty usefull to know if swing A is faster than swing B in a particular practice session. When you want more speed, all you want to know is if your new move or swing though or technical change is going to give you more or less speed, looking at the decibels is really easy to see that and you don't need to spend money on launch monitors. 
Of course, if you want someting that can compare your speed from place to place, session to session or club to club then you don't have much choice than go and get the launch monitor you can afford. 

Bonus: Linear regresion of both variables.  Y: db, X: m/h

Correlation might be there, but I don't think that really helps you get where you want to be. For example, I see a 67.4 from the sound app going with a PRGR reading of 79.0 and a 67.2 from the sound app going with a 85.0. Bear in mind most people are going to be swinging a club at roughly similar speeds most of the time, so the range of speeds with a 7 iron swing might be say 88-91 for a given player. That's fairly tight and just based on what you're showing above, you're looking at sound numbers that are going to be wider than the spread of speeds for the same exact speed every time. You've got a 6 mph swing speed difference in the table with a 0.2 difference in sound and going the wrong way. I don't think given that you'll get anything valuable out of this, even if you could set it up perfectly every time. 

Having said that, I'd think that your own ears are probably better at figuring out how loud the woosh is than the decibel meter. Our ears are very good at pinpointing a specific frequency to focus on, which the sound app won't do. Your ears are also going to be permanently about the same distance from the clubhead. It's not going to be scientific, but you could probably tell whether one swing is faster than another based on how they sound if that's what you're focused on. Certainly not going to be useful session to session, but swings back to back if you're just trying to swing faster than you did last time, you might have a chance of telling that from the sound you hear. 

[billchao]

17 hours ago, p1n9183 said:

The other posters that daily brought down the idea without proper arguments or proof, disappeared after been confronted with actual data.

Ok great, now do it again. And again. And again. And then change variables. Ambient temperature, distance of the phone, surrounding environment. Do it with different people swinging the club. Did you test only your 6 iron or did you try different clubs at different speeds?

You can't perform one test and declare your results conclusive.

[p1n9183]

On 10/1/2024 at 6:42 PM, iacas said:

Uh, that's not what happened. I'm highly dubious about how your results would work going forward, you showed nothing about your setup, etc.

Despite I explained my setup (no pictures), is not important. the important thing is to keep the same setup swing after swing. 

But hey, don't trust my testing . Do one on your own and see if the result are as bad as you anticipated earlier or have some correlation as mine did. 

On 10/1/2024 at 8:20 PM, Ty_Webb said:

Correlation might be there, but I don't think that really helps you get where you want to be. For example, I see a 67.4 from the sound app going with a PRGR reading of 79.0 and a 67.2 from the sound app going with a 85.0. Bear in mind most people are going to be swinging a club at roughly similar speeds most of the time, so the range of speeds with a 7 iron swing might be say 88-91 for a given player. That's fairly tight and just based on what you're showing above, you're looking at sound numbers that are going to be wider than the spread of speeds for the same exact speed every time. You've got a 6 mph swing speed difference in the table with a 0.2 difference in sound and going the wrong way. I don't think given that you'll get anything valuable out of this, even if you could set it up perfectly every time. 

In fact my only objective was exactly that, to probe that the woosh of the club and the speed of the club are related and is could be usefull. You are right to point out that the numbers are not perfect, but remember that the PRGR also have accurracy errors (from time to time I get reading wih my 6 iron from 100 to 110 m/h that are of course bad readings ), even the trackman have. But for a free app I think is a good aproximation. Olso knowing this you can swing 10 swing with the old way and 10 with the new way and average the results, numbers are going to be a little more accurate. 

 

On 10/1/2024 at 8:20 PM, Ty_Webb said:

you could probably tell whether one swing is faster than another based on how they sound if that's what you're focused on

Feeling from real are 2 different things. Before having the launch monitors (an event after) I would test new swing and thougth that they were more fast, just to be proven wrong after testing them with balls on the course. Maybe it's just me.  

But it could be a cool experiment if you could predict the speed of the club agianst a speed metter better than the decibel meter can.  

On 10/2/2024 at 11:48 AM, billchao said:

You can't perform one test and declare your results conclusive.

In fact is proven by science that you could know the speed of an object by the sound it produces. I think we all agree that the more speed you move the club, the more louder whoosh you generate. I tested a single time to prove my teory and results were better that I or everyone spected. Would I spend more time doing it? of course not, I suggest the idea, if someone wants to use it or dig deeper, then great. I already have a PRGR but I would love to know this a few years back to experiment further and use it for my own game. 

[iacas]

Just now, p1n9183 said:

Despite I explained my setup (no pictures), is not important. the important thing is to keep the same setup swing after swing.

I disagree.

Just now, p1n9183 said:

But hey, don't trust my testing . Do one on your own and see if the result are as bad as you anticipated earlier or have some correlation as mine did.

I'm not a big fan of wasting my time. 🤣

[boogielicious]

There is a whole bunch of more testing and analysis to even remotely show whether your test was statistically significant. I’ve done hundreds of designed experiments that were properly set up. This is not one of them and no I’m not going to waste my time repeating yours.

[GolfLug]

3 hours ago, boogielicious said:

There is a whole bunch of more testing and analysis to even remotely show whether your test was statistically significant. I’ve done hundreds of designed experiments that were properly set up. This is not one of them and no I’m not going to waste my time repeating yours.

Yes, I had already mentioned that the Gage R&R required for the level granularity is simply not enough. @p1n9183, good thought m y friend, but I would suggest you let this go. 

Edited October 4, 2024 by GolfLug