# 0.75Hz



## dvsDave (Sep 30, 2019)

I got an email for a new kickstarter product and some of the product's claims caught my eye.

This QOTD is open to all right out of the gate. Show the math and reasoning for why this product's claims are highly suspect.


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## EdSavoie (Sep 30, 2019)

Mostly because the ear bottoms out at around 20Hz?
Ignoring that, it's an awfully small driver to audibly reproduce sub-sonic frequencies on the scale of a room rather than headphon-

waaaait, is that little thing battery powered?


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## dvsDave (Sep 30, 2019)

EdSavoie said:


> Mostly because the ear bottoms out at around 20Hz?
> Ignoring that, it's an awfully small driver to audibly reproduce sub-sonic frequencies on the scale of a room rather than headphon-
> 
> waaaait, is that little thing battery powered?



No idea, it's on Kickstarter as the Banala Lite.


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## JonCarter (Sep 30, 2019)

L:ike most of such products, it's a device to make $$$ for the seller. He'll make a bunch of it before enough publicity about "Another useless product" appears and he DISappears. People will by anything.


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## rsmentele (Oct 1, 2019)

I highly doubt this device can produce a .75 hz wavelength... a 10hz wave is 112' in full length.... that's a lot of wave to push through a 3" driver....


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## gafftaper (Oct 1, 2019)

rsmentele said:


> I highly doubt this device can produce a .75 hz wavelength... a 10hz wave is 112' in full length.... that's a lot of wave to push through a 3" driver....


That's easy to solve. It just pushes the 112' wave out of the 3" driver in a straight line.


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## MNicolai (Oct 2, 2019)

Fun fact: A 10Hz wave is approximately 200 bananas long.

Bananas, being a ANSI standard measurement for distance. I've created a helpful Frequency to Bananas reference chart, applicable so long as your bananas are stored at room temperature.





EDIT: Had the incorrect Feet:Bananas conversion at the bottom. Fixed it.

1 Banana = 7.008 inches, per international standard.


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## dvsDave (Oct 2, 2019)

MNicolai said:


> Fun fact: A 10Hz wave is approximately 200 bananas long.
> 
> Bananas, being a ANSI standard measurement for distance. I've created a helpful Frequency to Bananas reference chart, applicable so long as your bananas are stored at room temperature.
> View attachment 18524


You win the internet today


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## Michael K (Oct 2, 2019)

Hm... I'll have to break out my physics textbook and notes to get you the math (when I have a bit of that free time stuff), but there is absolutely no way that will put out frequencies that low at any meaningful amount of power.


MNicolai said:


> Bananas, being a ANSI standard measurement for distance. I've created a helpful Frequency to Bananas reference chart, applicable so long as your bananas are stored at room temperature.View attachment 18524


Can I eat the bananas before I make my measurements, or do I have to wait till my state/federally required break? Does use as a measuring utensil effect the nutritional value?


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## RonHebbard (Oct 2, 2019)

Michael K said:


> Hm... I'll have to break out my physics textbook and notes to get you the math (when I have a bit of that free time stuff), but there is absolutely no way that will put out frequencies that low at any meaningful amount of power.
> 
> 
> Can I eat the bananas before I make my measurements, or do I have to wait till my state/federally required break? Does use as a measuring utensil effect the nutritional value?


No but Mike's chart has real apeal. 
Toodleoo! 
Ron Hebbard


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## TimMc (Oct 2, 2019)

It's all good until Blue Man Group shows up and the props guy "borrows" your *calibrated* banana...


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## RonHebbard (Oct 2, 2019)

TimMc said:


> It's all good until Blue Man Group shows up and the props guy "borrows" your *calibrated* banana...


I wonder if there are Imperial and Metric calibrated bananas*??* 
In my shop daze we built at least two sets for the Blue Man Group, complete with gentle rakes and a gutter across the DS edge for hosing down between performances. 
Toodleoo! 
Ron Hebbard


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## gafftaper (Oct 2, 2019)

RonHebbard said:


> No but Mike's chart has real apeal.
> Toodleoo!
> Ron Hebbard


BOOO!!!!


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## Van (Oct 2, 2019)

There was a research group, years ago, using Harmonics to induce lower brainwave frequencies in the auditory processing centers of the brain. The idea was simple enough, run a 100Hz tone in one ear, and a 101Hz signal into the other and the Nerve pulses harmonize and create a 1 Hz. Pulse in the Brain. I don't know how this would work with a single speaker as the original system required headphones to isolate the tones stereoscopically. 
I think using a motorcycle helmet with transducers firing Targeted Magnetic pulses is a much better, much more proven method of inducing particular brain waves.


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## DrewE (Oct 2, 2019)

10 Hz and 100 Hz would produce 110 Hz and 90 Hz resultant frequencies, not 1 Hz. (More generally, the new frequencies are the sum and difference of the originals.) There is not generally any need to isolate the sounds to accomplish that. There are plenty of examples in everyday life where miniscule differences in the frequency of two sounds beat at a clearly heard low frequency; one good example is flying on a twin engine propeller airplane when the engines are barely not in sync, resulting in that breeeoooaaaeeeoooaaar sort of sound.

This basic technique is sometimes used on pipe organs to obtain something resembling pedal bass stops that otherwise would need a pipe that is inconveniently long. Instead of a 16' stop, for instance, a small instrument may employ an 8' stop (2x the frequency) and--if memory serves--a 5 1/3' stop (3x the frequency) sounded together.


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## RonHebbard (Oct 2, 2019)

Van said:


> There was a research group, years ago, using Harmonics to induce lower brainwave frequencies in the auditory processing centers of the brain. The idea was simple enough, run a 100Hz tone in one ear, and a 101Hz signal into the other and the Nerve pulses harmonize and create a 1 Hz. Pulse in the Brain. I don't know how this would work with a single speaker as the original system required headphones to isolate the tones stereoscopically.
> I think using a motorcycle helmet with transducers firing Targeted Magnetic pulses is a much better, much more proven method of inducing particular brain waves.


 *@Van* Did this lead to lack of bowel control and containment issues*?? * This sounds like experiments Mr. Danley would run and / or something the German's would've experimented with in the second world war. 
Toodleoo! 
Ron Hebbard


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## Van (Oct 2, 2019)

DrewE said:


> 10 Hz and 100 Hz would produce 110 Hz and 90 Hz resultant frequencies, not 1 Hz. (More generally, the new frequencies are the sum and difference of the originals.) There is not generally any need to isolate the sounds to accomplish that. There are plenty of examples in everyday life where miniscule differences in the frequency of two sounds beat at a clearly heard low frequency; one good example is flying on a twin engine propeller airplane when the engines are barely not in sync, resulting in that breeeoooaaaeeeoooaaar sort of sound.
> 
> This basic technique is sometimes used on pipe organs to obtain something resembling pedal bass stops that otherwise would need a pipe that is inconveniently long. Instead of a 16' stop, for instance, a small instrument may employ an 8' stop (2x the frequency) and--if memory serves--a 5 1/3' stop (3x the frequency) sounded together.


However, the ear is not capable of, reliably hearing any frequency below 20hz. So if you want to influence Alpha waves you need to use freqs you can reliably hear, say 100hz in one ear, and 101 in the other. The whole point of the experiment was not to induce 1 hertz waves through the air, but instead to produce them in the brain.


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## Malabaristo (Oct 2, 2019)

I had to look up "isochronic" because I wasn't sure it was a real word. It turns out the idea is that they're not actually making a 1Hz tone, they're playing a tone somewhere in the audible range and turning it on and off at a rate of 1Hz with the idea that will still sync your brain somehow...

So, the physics of it are fine, but the neural effectiveness is still very questionable at best.


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## TimMc (Oct 4, 2019)

DrewE said:


> 10 Hz and 100 Hz would produce 110 Hz and 90 Hz resultant frequencies, not 1 Hz. (More generally, the new frequencies are the sum and difference of the originals.) There is not generally any need to isolate the sounds to accomplish that. There are plenty of examples in everyday life where miniscule differences in the frequency of two sounds beat at a clearly heard low frequency; one good example is flying on a twin engine propeller airplane when the engines are barely not in sync, resulting in that breeeoooaaaeeeoooaaar sort of sound.
> 
> This basic technique is sometimes used on pipe organs to obtain something resembling pedal bass stops that otherwise would need a pipe that is inconveniently long. Instead of a 16' stop, for instance, a small instrument may employ an 8' stop (2x the frequency) and--if memory serves--a 5 1/3' stop (3x the frequency) sounded together.



Such organ stops were usually in the pedal division with the word "resultant" part of the stop name. 32' Resultant Principal were fairly common as a cost saving. The bottom octave of a real 32' pedal stop cost as much as or more than the next 2.5 octaves. It fooled your ear/brain but probably not your trouser legs.

In electronic processing there is a device called MaxxBass, and is also available as a Waves plug-in. It works in a very similar way - using harmonics to create the impression of a sub-octave. Contrast with the dbx 500 and 120 "boom box" processors from decades back which were based around octave dividers.


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## JD (Oct 4, 2019)

15 Hz induces vomit. I wounder what digestive effects <10 Hz produce? Better get out the plastic bed sheets! 
As for pipe organs, many use a "Speaker Stop" for the 32 foot rank. Generally, you would have to double the size of the casement to pipe it as the size of the pipes is equal to the complete size of all other ranks combined, in most cases. 
And then there's the 64 foot stop....


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## TimMc (Oct 4, 2019)

Not to go off into the weeds of pipe organs but those long, large pipes need considerable air volume, pipe chamber real estate, and mechanical support, too. Those are expensive and why "resultant" and electronic pedal stops are used. The pic of the woman with the 64' pipe gives some perspective.

I think there are 2 playing instruments that have 64' stops in the USA - the Wannamaker in Philly and possibly the organ in Boardwalk Hall in Atlantic City (if they've gotten it restored to that point). The Atlantic City organ is a fairly high wind pressure instrument and some of stops have threaded pipe toes and wind chests to keep from launching the pipes into orbit.

Pipe organs can be fascinating instruments. If you have an opportunity to be in a pipe chamber while it's being played you're in for a new experience.


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## RonHebbard (Oct 4, 2019)

JD said:


> 15 Hz induces vomit. I wounder what digestive effects <10 Hz produce? Better get out the plastic bed sheets!
> As for pipe organs, many use a "Speaker Stop" for the 32 foot rank. Generally, you would have to double the size of the casement to pipe it as the size of the pipes is equal to the complete size of all other ranks combined, in most cases.
> And then there's the 64 foot stop....View attachment 18533


Along with the dual, multi-horse, three phase motors spinning the dual centrifugal blowers ramming air into the four, or more, expanded bellows with the weights on top. My favorite was the wind powered percussion section with the snare drum with three sticks: Two for playing and the third dedicated to rim shots. The concept of a three armed drummer always made me giggle. 
Toodleoo! 
Ron Hebbard


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## JD (Oct 4, 2019)

TimMc said:


> Pipe organs can be fascinating instruments. If you have an opportunity to be in a pipe chamber while it's being played you're in for a new experience.


Currently singing (temporary) in one choir where the loft is embedded in the pipe chest. Although some of the front pipes are decorative, the real pipes are directly behind. A very dreamy stereo experience!


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## tjrobb (Oct 5, 2019)

I worked for six years in a theatre from 1928 that still had the original organ. A) They are fascinating instruments. B) Actual two-phase power confuses a lot of electricians (used for the blower).


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## RonHebbard (Oct 6, 2019)

tjrobb said:


> I worked for six years in a theatre from 1928 that still had the original organ. A) They are fascinating instruments. B) Actual two-phase power confuses a lot of electricians (used for the blower).


One that's still in regular operation in our area has two centrifugal blowers each in the 25 to 30 horsepower neighborhood. The blowers fill four bellows each roughly 4' x 6' which grow from approximately 30" to a little over 6' in eight. The bellows have weight on their tops to force them rapidly down when their additional air is called upon to play sustained multi-note chords with multiple pedal pipes at high volume. I was always fascinated watching the bellows expand upon powering up then descending during play. Standing next to the bellows was like watching the organ breath. 
We used to have two similar organs in our area, one in a ~2,000 seat film theatre from the vaudville days, this is the one that had the snare drum with 3 sticks, one dedicated to playing rim shots, the other, the one still in well maintained regular operation, is in a Catholic minor Basillica. The Anglicans may have another real pipe organ but I can't attest to that (although I'm in regular contact with an Anglican who often practices on his church's organ.) 
Toodleoo! 
Ron Hebbard


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## Jay Ashworth (Oct 6, 2019)

Yep, multi-horse.

I'm told that 40-50HP motors are not at all uncommon on organs with 32' and 64' stops.

Such motors require a 480V 3ph separate service at at least 30A per leg, per motor, if not 50A.


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## RonHebbard (Oct 6, 2019)

Jay Ashworth said:


> Yep, multi-horse.
> 
> I'm told that 40-50HP motors are not at all uncommon on organs with 32' and 64' stops.
> 
> Such motors require a 480V 3ph separate service at at least 30A per leg, per motor, if not 50A.


 *@Jay Ashworth* Agreed; 277 / 480 on your side of Donald's walls, 347 / 600 up here on my side. 
Toodleoo! 
Ron Hebbard


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## Jay Ashworth (Oct 6, 2019)

In the US, 600 commences Medium Voltage (well, unless you're a Utility guy, in which case, MV is 4KV to probably 14KV), and requires much more expensive electricians.


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## RonHebbard (Oct 6, 2019)

Jay Ashworth said:


> In the US, 600 commences Medium Voltage (well, unless you're a Utility guy, in which case, MV is 4KV to probably 14KV), and requires much more expensive electricians.


 *@Jay Ashworth* Up here, north of the walls, 120 /240, 120 / 208 and 347 / 600 are the common voltages we see in homes, strip malls and light, very light, industries. 13.8 KV and 27.6 KV are the highest we'd normally find feeding larger buildings, theatres and running around university campuses. Above 27.6 KV is up poles or towers and the lasses and lads from our power companies pay us a visit. 
Toodleoo! 
Ron Hebbard


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## tjrobb (Oct 7, 2019)

Jay Ashworth said:


> In the US, 600 commences Medium Voltage (well, unless you're a Utility guy, in which case, MV is 4KV to probably 14KV), and requires much more expensive electricians.


The newest NEC bumped low-voltage to 1000V, largely to incorporate solar systems.
Utilities often go MV thru 34.5kV, as there are several large industries that use it (I know of four plants in our city, maybe more, all are in food production FWIW).


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## Jay Ashworth (Oct 8, 2019)

Yeah, the only place around here I see any delivery higher than 14kV is things like mills and stuff; everything else is transmission and sub-T voltages.


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## JonCarter (Oct 8, 2019)

But to get back to the original subject as I said a long time ago, "Like most of such products, it's a device to make $$$ for the seller. He'll make a bunch of it before enough publicity about "Another useless product" APppears and he DISappears. People will by anything.

"Emperor's new clothes" all over again.


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