Hi everyone,
Somethings been bugging me about a cabinet design i have seen on a bose soundtouch 30
Which i repaired for myself.
I know the theory of how a TL works and this is used for the bass with a rather
Oddly sized 7inch woofer in the back with the trade mark tubes inside, both sides of the woofer are driving into tubes with one set shorter than the other it seems like a mini
Version of the bose cannon only folded up, its different to the wave radio set up as i have seen those too (bass is also very nice and butter smooth down to about 36hz then it starts to roll off.
However its the front that i cant figure out, we all know about the old story of the mid range
Hole which is so often bashed on the cinema stuff however i dont hear it on this and it seems beautifully smooth with sweet treble so i had a pick around in the front too and
I have no idea whats going on so i want to understand.
You have the little 2 inch tweeters one each side angled extremely outward
And they seem to give all the really sweet surround effect treble (which i like very much it sounds so well defined like the tweeters in my b&w's) behind these are no horns just a normal sealed enclosure which again i understand.
However the mids which should be non existant are great and very open and refined again
But where the hell from! Then i noticed these two different sized slots like an
Inverted triangle in two sizes about 2cm under the tweeters, these are closed at the rear
And have no drivers however they are blasting very nice midrange with definite
Horn style clarity straight out toward the listener, i thought maybe its some trick
With dsp so i cover the tweeter with my hand and the treble is gone but the mids
Are still blasting clear as day so i cover the the slots now the mids are gone and treble
Is unchanged, so its a 3 way gotta be a first for bose but how?
These slots are part of the case moulding and it would seem from covering
Each sized slot seperately they do different mids so maybe even a 4 way? But
Again no drivers there, these are closed crevices.
however the sealed enclosure for the tweeter goes
Over and behind these slots and the slots pertrude into the tweeter enclosure like an L shape so are they somehow exciting them to reasonate
With the tweeter, its very strange and i have never seen this idea before
From bose its something new, also they are loud not subtle you would
Think they have their own drivers but theres no space behind just the
Inside of the tweeter sealed box.
Any ideas? I have googled every concept i can imagine but only thing i find
Is an article about cavity noise on aeroplane doors induced by air rushing
Past, but there is no air rushing past the leading edge on these the tweeters
Actually point away from the crevices.
Edit, just pondering looking at the inside some more there is a metal insert on the end of each triangle
Point moulded into the inside of the enclosure for the tweeter, it sticks out into a long slither.
They stick out into the chamber and are different lengths and quite rigid but tapping on one with a Screwdriver
Induces a fairly loud tap in the crevice so im thinking they must act like a tuning fork resonating at different
Octaves and exciting the cavity, its wierd and if it works how i think its so alien!
Somethings been bugging me about a cabinet design i have seen on a bose soundtouch 30
Which i repaired for myself.
I know the theory of how a TL works and this is used for the bass with a rather
Oddly sized 7inch woofer in the back with the trade mark tubes inside, both sides of the woofer are driving into tubes with one set shorter than the other it seems like a mini
Version of the bose cannon only folded up, its different to the wave radio set up as i have seen those too (bass is also very nice and butter smooth down to about 36hz then it starts to roll off.
However its the front that i cant figure out, we all know about the old story of the mid range
Hole which is so often bashed on the cinema stuff however i dont hear it on this and it seems beautifully smooth with sweet treble so i had a pick around in the front too and
I have no idea whats going on so i want to understand.
You have the little 2 inch tweeters one each side angled extremely outward
And they seem to give all the really sweet surround effect treble (which i like very much it sounds so well defined like the tweeters in my b&w's) behind these are no horns just a normal sealed enclosure which again i understand.
However the mids which should be non existant are great and very open and refined again
But where the hell from! Then i noticed these two different sized slots like an
Inverted triangle in two sizes about 2cm under the tweeters, these are closed at the rear
And have no drivers however they are blasting very nice midrange with definite
Horn style clarity straight out toward the listener, i thought maybe its some trick
With dsp so i cover the tweeter with my hand and the treble is gone but the mids
Are still blasting clear as day so i cover the the slots now the mids are gone and treble
Is unchanged, so its a 3 way gotta be a first for bose but how?
These slots are part of the case moulding and it would seem from covering
Each sized slot seperately they do different mids so maybe even a 4 way? But
Again no drivers there, these are closed crevices.
however the sealed enclosure for the tweeter goes
Over and behind these slots and the slots pertrude into the tweeter enclosure like an L shape so are they somehow exciting them to reasonate
With the tweeter, its very strange and i have never seen this idea before
From bose its something new, also they are loud not subtle you would
Think they have their own drivers but theres no space behind just the
Inside of the tweeter sealed box.
Any ideas? I have googled every concept i can imagine but only thing i find
Is an article about cavity noise on aeroplane doors induced by air rushing
Past, but there is no air rushing past the leading edge on these the tweeters
Actually point away from the crevices.
Edit, just pondering looking at the inside some more there is a metal insert on the end of each triangle
Point moulded into the inside of the enclosure for the tweeter, it sticks out into a long slither.
They stick out into the chamber and are different lengths and quite rigid but tapping on one with a Screwdriver
Induces a fairly loud tap in the crevice so im thinking they must act like a tuning fork resonating at different
Octaves and exciting the cavity, its wierd and if it works how i think its so alien!
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Id love to but it seems this website is incompatible with technology from this century ie uploading from a smartphone! I have pics from when i stripped it down but it wont upload here i tried.
Mat.
Mat.
I think that file is exactly how the rear subwoofer is set up and is interesting, however the front is the really wierd part on this unit.
It does mention about sealed chambers adjacent to the driver but it seems to refer to the rear driver, mine does not have such a chamber, this manual seems to describe the sound dock 10 i owned one of these once but it didnt have anywhere near the power of this unit.
Interesting read thanks.
It does mention about sealed chambers adjacent to the driver but it seems to refer to the rear driver, mine does not have such a chamber, this manual seems to describe the sound dock 10 i owned one of these once but it didnt have anywhere near the power of this unit.
Interesting read thanks.