Pocket Rocket
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- windshieldbug
- Once got the "hand" as a cue
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Aw, come on guys! Can't we analyze our impulses and hammer on a viola, instead!?Lays it on thick wrote:These are graphs taken with an impulse analyzer, of the frequency response of a violin (upper frequency limit of 1kHz) with and without a Pocket Rocket next to but not touching it (sitting on the same foam isolation pad.)
There is a piezoelectric pickup in a small "hammer" and another in a pickup that is in firm contact with the top plate near the bridge. The signals from lightly striking the violin from both pickups are sent to the analyzer where the striking impulse force has to fall within a preset window. The small differences that remain are scaled within the analyzer, and then averaged over a count of eight valid hits.


Instead of talking to your plants, if you yelled at them would they still grow, but only to be troubled and insecure?
- windshieldbug
- Once got the "hand" as a cue
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Probably not since each one is specificly designed for your instrument that one being specifically the next one out of the pile they pick upbloke wrote:damn...I wonder if I can get a refund...??
Instead of talking to your plants, if you yelled at them would they still grow, but only to be troubled and insecure?
- Rick Denney
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Re: Pocket Rocket
The body's characteristic resonance?pulseczar wrote:Now I know the secret to a world class sound!
http://vansevers.com/pocket_rocket.html
That's easy to determine. Hang the charlatan selling this claptrap by his thumbs, and smack him with a hammer. The resulting ring will tell you the characteristic resonance. Try it with and without the Pocket Rocket. Try it many times. Keep trying it.
Make sure you measure each ring down in the noise, so that any influence on the sound from the vent on the AC unit to the quantity of water in the glass on the table will have an effect. Then, compare the random noise from one sample to the random noise for another sample, to prove that they are different. I would be impressed if they were the same. The FTA should have something to say about that "proof".
If you just get a simple thud, which would normally indicate that the body has no acoustic resonance at all, (as would be expected from a bag of jello), then you are obviously doing it wrong. Keep trying till you get it right.
Once the perpetrator of this crap expires, the test is complete. That would be a successful test of the system--the Pocket Rocket, in that case, did indeed make the world a better place.
Rick "fighting parody masquerading as truth with truth masquerading as parody" Denney
Re: Pocket Rocket
Now, that you have given us your prepared statement and before you can be confirmed as Resident Genius, you must give us your opinion on waterboarding.Rick Denney wrote:That's easy to determine. Hang the charlatan selling this claptrap by his thumbs, and smack him with a hammer. The resulting ring will tell you the characteristic resonance. Try it with and without the Pocket Rocket. Try it many times. Keep trying it.
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- 4 valves
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Re: Pocket Rocket
Only with the right partner.Mark wrote:Now, that you have given us your prepared statement and before you can be confirmed as Resident Genius, you must give us your opinion on waterboarding.Rick Denney wrote:That's easy to determine. Hang the charlatan selling this claptrap by his thumbs, and smack him with a hammer. The resulting ring will tell you the characteristic resonance. Try it with and without the Pocket Rocket. Try it many times. Keep trying it.
Right partner:

Wrong partner:

Note lack of good wave action in second picture. Though it would be more difficult to fall off that board.
- windshieldbug
- Once got the "hand" as a cue
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- Rick Denney
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Re: Pocket Rocket
I prefer it to nuclear explosions in major American cities.Mark wrote:Now, that you have given us your prepared statement and before you can be confirmed as Resident Genius, you must give us your opinion on waterboarding.
Rick "who says that with confidence knowing nothing about waterboarding except that some U.S. military types have volunteered for it in their training" Denney
Re: Pocket Rocket
Confirmed!Rick Denney wrote:I prefer it to nuclear explosions in major American cities.Mark wrote:Now, that you have given us your prepared statement and before you can be confirmed as Resident Genius, you must give us your opinion on waterboarding.
Rick "who says that with confidence knowing nothing about waterboarding except that some U.S. military types have volunteered for it in their training" Denney
- Rick Denney
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In the radio frequency world, resonance occurs when inductive reactance equals capacitive reactance. When there is no simple resistance, such that there is approaching perfect conductors between an inductor and a capacitor, the quality of the resonance is very high. That means that it rings like an SOB. Point: The better the resonance, the narrower the band of frequencies over which it resonates.Coder wrote:I perform with my tuba and an electronic setup from time to time in coffee shops and such, using a mic in the bell, and I could see were a series of resonators might be more useful, but I could probably build what I'd need for much less than any of these VansEvers products.
There is no such thing as a broad-band resonator. In fact, it's a contradiction in terms.
Thus, any resonator used to enhance the sound of any instrument would have to be tuned to whatever note that instrument was playing to have any appreciable effect.
(Besides, it seems to me the instrument comes with its own highly tuned resonator.)
Rick "who didn't see no tuning knobs on that thingy" Denney
- windshieldbug
- Once got the "hand" as a cue
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What's a piano soundboard, then?Rick Denney wrote:There is no such thing as a broad-band resonator. In fact, it's a contradiction in terms
(And I ask that out of ignorance, not as the smart-*** I think I am... nor did any of that look close to such a device)
Instead of talking to your plants, if you yelled at them would they still grow, but only to be troubled and insecure?
- Rick Denney
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It's a good question, and it points out that my statement was perhaps a little too bold. You can have a thing that resonates over a wide range of frequencies, but it will either have to be really big, or the resonance quality will be very low.windshieldbug wrote:What's a piano soundboard, then?Rick Denney wrote:There is no such thing as a broad-band resonator. In fact, it's a contradiction in terms
(And I ask that out of ignorance, not as the smart-*** I think I am... nor did any of that look close to such a device)
When you damp the vibrating piano string by lifting your finger, the large soundboard will continue to vibrate if undamped. It attenuates much faster than the string, which indicates much lower resonance quality. It trades resonance quality for broadbandedness. Compare it with the string itself, which when unstopped attenuates much more slowly.
The soundboard is a low-quality sympathetic resonator that couples with the vibration of the string to amplify it. It needs to be broadbanded so you don't have to tune it, and you don't want it to resonate very well or it would ring more on some notes than others and would continue to ring after you stop the excitation. So, you shape it funny to smooth out the resonance peaks.
A bass drum is a low-quality resonator, and it has to be big to resonate much at all. It's specifically untuned so that it doesn't resonate on any particular frequency, which means it's broadbanded. But even if you really whack it, it still only rings for a maybe a second.
Contrast that with a large tympanum. When the head is tuned to resonate well on a specific frequency, it will ring for a much longer time. But even tympani are low-quality resonators. Compare them with the tube under a vibraphone. Those tubes are really random-size resonators, and they work because they are big compared to the vibrations of the whatever-it-is-those-wood-things-are-called. Now, compare all those to chimes. Those are high-quality resonators, and they ring much longer than any drum head however carefully tuned. But as you move up this food chain, the longer ring accompanies the narrower range of frequencies.
Rick "suggesting that a pocket resonator might have a useful tuba-enhancing broadbanded resonance effect if it was the size of, say, Avery Fisher Hall" Denney
- windshieldbug
- Once got the "hand" as a cue
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