In Bass reflex box (vented)-If I make smaller box than what consequences will I have?

[eliaselias_0]

I found this little woofer:
https: / / www.madisound.com/store/manuals/seas/H1217.pdf
I like the features but the manufacturer suggests 56 liters box bass reflex for f3 32Hz.
I want a smaller box.
If I make less than what consequences will I have?
It will suit me box 30 liters.
I will have impact only on f3 or elsewhere?
There is an algorithm that shows the consequences?
Thank you!

[AndrewT]

download WINisd pro.
try different volumes and different vent lengths.
You will find that too small a box creates a "hump" in the frequency response. Great if you are using a driver/box that has a very high F3 and you want to create a bass effect by exaggerating the 2nd harmonic. This is very intolerant of room variations and can sound bad on male voice.

A slightly drooping response avoids the bass exaggeration and helps reduce that male voice sensitivity. It is easier to place in the room.

A true "Butterworth" rolloff (Q=1/sqrt(2)) looks nice, but in a room it falls between the two examples above.

[sreten]

Hi,

That driver is intended for sealed boxes not vented, ~13L stuffed.

But 30L tuned to 33Hz looks good to me, but a big box for a 6.5".
Good bass but limited bass power handing, well suited to valves.

Other options may work better, 30L can take 2 vented 6.5"ers.

rgds, sreten.

[eliaselias_0]

I am thinking to use it in a 3-way as woofer 33Hz to 250Hz.
Is it possible this?

[eliaselias_0]

Originally Posted by AndrewT

download WINisd pro.
try different volumes and different vent lengths.
You will find that too small a box creates a "hump" in the frequency response. Great if you are using a driver/box that has a very high F3 and you want to create a bass effect by exaggerating the 2nd harmonic. This is very intolerant of room variations and can sound bad on male voice.

A slightly drooping response avoids the bass exaggeration and helps reduce that male voice sensitivity. It is easier to place in the room.

A true "Butterworth" rolloff (Q=1/sqrt(2)) looks nice, but in a room it falls between the two examples above.

Thank you for WINisd pro.
Very usefull program.

[sreten]

Originally Posted by eliaselias_0

I am thinking to use it in a 3-way as woofer 33Hz to 250Hz.
Is it possible this?

Hi, its certainly possible, but it is designed for sealed 2 ways, rgds, sreten.

3 ways are very difficult to design - check out these sites/designs.

Use WinISDPro to model bass max SPL and max bass power handling.

undefinition
Zaph|Audio
FRD Consortium tools guide
RJB Audio Projects
Speaker Design Works
HTGuide Forum - A Guide to HTguide.com Completed Speaker Designs.
Humble Homemade Hifi
DIY Loudspeaker Projects Troels Gravesen

[eliaselias_0]

Originally Posted by sreten

Hi, its certainly possible, but it is designed for sealed 2 ways, rgds, sreten.

3 ways are very difficult to design - check out these sites/designs.

Use WinISDPro to model bass max SPL and max bass power handling.

undefinition
Zaph|Audio
FRD Consortium tools guide
RJB Audio Projects
Speaker Design Works
HTGuide Forum - A Guide to HTguide.com Completed Speaker Designs.
Humble Homemade Hifi
DIY Loudspeaker Projects Troels Gravesen

Very helpfull.
Thx