Time to put theory into practice :wink: do you think it could be built?
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Time to put theory into practice :wink: do you think it could be built?
so easy its not funny , it will take a while , each sheet might be 1 hour in the CNC , but ill just run them while im working on my violin
a lot of glue ??/ i always have some left over epoxy from carbon fibre builds , so will use some dam expensive glue ( even some out of date stuff) , it will also water proof the partial board , was thinking of "latex rubber " coating the inside of the snail and blow holes
Well if you decide to go ahead and give it a go I will be watching with interest to see the results. Do you have any decent test gear to measure the results?
got a set up for violins , should work the same , run the speaker at set hz , use salt to see the patterns forming on the sides , the salt moves to the "nodes" area's of least movement , then i have a record player head , set up to record vibrations ,where the salt shows you ( where the salt isnt ) , so can tell what hz the box is vibrating at for each wave length the speaker is humming at , but dont have a decent mic (db accurate )
i use voice recognition soft ware for my violins , not just the spectrum analyser , its a lot easier to understand
the setup has one PC running a tone generator ( CNC's PC ) with voice recognition showing its out put ,on screen . its sound card is a 24bit , thats amped to 90watts per channel ,
the record player head runs through a preamp into a second PC with the same sound card to show a voice recognition pattern of what it saw , between the 2 screens its easy to see the difference ( yer i have PC's in my shed , LOL , 3 of them )
i place a finished violin between 2 speakers ( one is wired up wrong ) so the violin is forced to vibrate in time to the tone , the violin adds its acoustics to it , and the record player head on the bridge picks up what the violin is playing , i can then attack the bridge with a gouge to fine tune the loudness of each string , im playing them backwards because i cant play them ,
the speakers move the violin up and down , while the record player head only picks up side to side movement of the bridge , there is no feed back , and the its only the note being played has a spike , its under tones are the same as if it was played by a bow , i do have to clamp a string to the corresponding note , the spot is easy to find because the string vibrates in tune when the clamp is move into position, i open up mutable tone generators to test cords
at 90rms , its easy to make it wolf tone from way too much power ,its good , lets me see how far off i am from a wolf tone , a player would destroy the bow if they played that hard , tried to brake a string once and had all my neighbours complaining , "e" that loud sent me cross eyed
also experimenting with bouncing a IR laser off mirror tape to find out what hz the "tags" next to the F holes vibrate at , if you touch them they slow down , at the moment i use a pencil with an eraser on the end , touch the tag and see what area of the image stops
just got me thinking , find the node points of the sides of the box , and mount it by those node positions ( where is not vibrating ) , inside the outer shell of the speaker box
lay the speaker on its side , pump a fixed tone into it , shake on some salt , when it forms lines , mark the lines with hz referance , and go up to the next note and repeat , once you cover the range that the cross over will be supplying ,, look for a spot where the nodes are all the the time , or best spot , and thats your fixing position , ??? a rubber mount around the speaker hole to stop vibration ?