Hi everybody,
since nobody else - not the driver's manufacturer, nor the music dealer - could/would/did answer my request to my satisfaction, i would be truly grateful for any help on this subject.
I have an old, closed back, 66,05 litre bass (guitar) cabinet, which is hopefully soon to be equipped with a new 10" bass woofer speaker.
To enhance the bass, there is a rectangular 18 x 6 cm bassreflex port already cut into the 2.1 cm front panel (gives it a volume of 0,2268 litres, right?). I don't know the original speaker the cabinet was built for - looks like a homemade job but it's quite sturdy, well-done - so i can't figure out if the bassreflex ports size has been calculated properly or just been cut by rule of thumb ... (?)
The Thiele/Small parameters to the speaker i've already picked (an Eminence 'Legend BP102-4', small but very powerful) are luckily provided along with other technical data on the manufacturer's website.
My problem: in question is if i can use the already-cut bassreflex port as is, or if i have to alter its size - ? Therefore i would have to know how to calculate its ideal dimensions, or maybe a range of possible sizes - unfortunately, although i found lots of 'cabinet size calculators' on the net it seems, there is not one out there that allows for this special job ...
Using online calculators or simulation softwares for cabinets seem to either work to create virtual cabinets from scratch only, impossible to type in already existing dimensions(?) - or they come up with data results i do not understand, like abstract curves, frequency stuff and the likes - instead of (what i was expecting - might be a bit naive) a more clear range of possible sizes for optimum speaker operation.
My misconception? ...
I really don't expect anybody to do calculation stuff for me (!) - i just really need some hint on how to proceed:
does anybody of you guys have an idea on how to exactly calculate a bassreflex port - say, which formula to use? Which of the Thiele/Small parameters to put in use here -
and then: if using a software - how to interpret (resonant?) frequency results and such stuff to turn this abstract nonsense, ah, excuse me - this doctoral thesis into a worke horse for a working musician? ...
The general goal is to make sure the speaker is able to deliver as much bass frequency and power as possible, for it will be in use for bass amplification as a second, 'woofer' cabinet along with a powerful, midrangy 2x12" box. Both will be fed through one main amp respectively.
I would be really happy if i would hear some recommendations.
Sorry, i'm only a musician who just wants to change one bass driver ... i really didn't expect having to get a doctor's degree on physics first ... quite an unexpected challenge.
Many, many thanks for any help,
all the best, mo
__________________________________________________________________________________________________________________________________________________
Edit: Sorry, if i sub-posted this under an obviously wrong category! Didn't get this concept - i assumed "post new thread" means posting an independant thread ... my fault. damn ...
since nobody else - not the driver's manufacturer, nor the music dealer - could/would/did answer my request to my satisfaction, i would be truly grateful for any help on this subject.
I have an old, closed back, 66,05 litre bass (guitar) cabinet, which is hopefully soon to be equipped with a new 10" bass woofer speaker.
To enhance the bass, there is a rectangular 18 x 6 cm bassreflex port already cut into the 2.1 cm front panel (gives it a volume of 0,2268 litres, right?). I don't know the original speaker the cabinet was built for - looks like a homemade job but it's quite sturdy, well-done - so i can't figure out if the bassreflex ports size has been calculated properly or just been cut by rule of thumb ... (?)
The Thiele/Small parameters to the speaker i've already picked (an Eminence 'Legend BP102-4', small but very powerful) are luckily provided along with other technical data on the manufacturer's website.
My problem: in question is if i can use the already-cut bassreflex port as is, or if i have to alter its size - ? Therefore i would have to know how to calculate its ideal dimensions, or maybe a range of possible sizes - unfortunately, although i found lots of 'cabinet size calculators' on the net it seems, there is not one out there that allows for this special job ...
Using online calculators or simulation softwares for cabinets seem to either work to create virtual cabinets from scratch only, impossible to type in already existing dimensions(?) - or they come up with data results i do not understand, like abstract curves, frequency stuff and the likes - instead of (what i was expecting - might be a bit naive) a more clear range of possible sizes for optimum speaker operation.
My misconception? ...
I really don't expect anybody to do calculation stuff for me (!) - i just really need some hint on how to proceed:
does anybody of you guys have an idea on how to exactly calculate a bassreflex port - say, which formula to use? Which of the Thiele/Small parameters to put in use here -
and then: if using a software - how to interpret (resonant?) frequency results and such stuff to turn this abstract nonsense, ah, excuse me - this doctoral thesis into a worke horse for a working musician? ...
The general goal is to make sure the speaker is able to deliver as much bass frequency and power as possible, for it will be in use for bass amplification as a second, 'woofer' cabinet along with a powerful, midrangy 2x12" box. Both will be fed through one main amp respectively.
I would be really happy if i would hear some recommendations.
Sorry, i'm only a musician who just wants to change one bass driver ... i really didn't expect having to get a doctor's degree on physics first ... quite an unexpected challenge.
Many, many thanks for any help,
all the best, mo
__________________________________________________________________________________________________________________________________________________
Edit: Sorry, if i sub-posted this under an obviously wrong category! Didn't get this concept - i assumed "post new thread" means posting an independant thread ... my fault. damn ...
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