Subwoofer terminology

[Speakers88]

front firing

how about front firing? I always hear subwoofers described as front- firing, but have never gotten definition of what it means.

 

[Pyrrho]

how about front firing? I always hear subwoofers described as front- firing, but have never gotten definition of what it means.

It means that the woofer is on the front of the cabinet, facing forward, like an ordinary speaker. A down-firing subwoofer is one in which the woofer is on the bottom of the cabinet (typically with feet holding the cabinet an inch or two above the floor, either with or without a bottom plate below the woofer actually on the floor below the posts holding the cabinet above it).

Here is an example of a front-firing subwoofer:

http://www.svsound.com/products-sub-box-pb13ultra.cfm

Here is an example of a down-firing subwoofer:

http://www.svsound.com/products-sub-cyl-pc13ultra.cfm

Either can work well, and I do not recommend selecting a subwoofer based on such a trivial matter. I do, however, rather like the SVS cylinder subwoofers, which are all down-firing. I like them not because they are down-firing, but because they take up little floor space for their size, and are light weight for their size, and are easier to pick up and move than most other subwoofers of their size, due to having a diameter that is easy to grab onto (plus the aforementioned relative light weight). They are also excellent subwoofers, but then so are SVS's traditional box subwoofers.

 

[l0gikal1]

This was very helpful, easy to follow and understand. Thank you for all the terminology described!

 

[modernprimitive]

if anyone out there is still watching, i have questions about folded horns. about all i know about them, is that the port continually increases in size over the length of the port, and that they are supposed to provide great bass response. i would like to learn more about these enclosures if possible.

thank you.

 

[fuzz092888]

Go here for folded horn plans and then on the left side there is a link that says "forum" register and ask questions. Bill is big in the folded horn area

http://billfitzmaurice.com

if anyone out there is still watching, i have questions about folded horns. about all i know about them, is that the port continually increases in size over the length of the port, and that they are supposed to provide great bass response. i would like to learn more about these enclosures if possible.

thank you.

 

[modernprimitive]

Go here for folded horn plans and then on the left side there is a link that says "forum" register and ask questions. Bill is big in the folded horn area

http://billfitzmaurice.com

thank you very much.

 

[modernprimitive]

yeah, so, those guys over there are a little nutty about subwoofers. it's awesome. really nice bunch. full of info. pretty much convinced that i NEED two tht cabinets. i think they will make me smile. thanks again for the help.

 

[Verdinut]

Mike and I have finally figured the situation out in part due to WmAx pointing me in the right direction too.

xmax is the total excursion in a completely linear fashion, thus no distortion is introduced via the driver moving in a non-linear fashion.

excursion is the total throw of the driver used in a specific application with a certain amount of chosen distortion (chosen by the subwoofer designer). The distortion is caused by the driver moving in a non-linear fashion and is generally not audible if properly implemented. Many manufacturers/designers have a set given amount of distortion that is allowed in a design caused by allowing a driver to have an excursion beyond its xmax.

http://www.subwoofer-builder.com/xmax.htm

Xmax is supposed to mean the maximum linear excursion one way only of a moving diaphragm or cone.

 

[Bigbri]

This is the first post that I have read since joining just today. I have just learned more by reading this page than I could have ever imagined! So glad I joined, and looking forward to imbibing information and learning going forward.....Brian

 

[Bigbri]

CORRECTION: "….first thread...."

 

[ryanosaur]

Xmax is supposed to mean the maximum linear excursion one way only of a moving diaphragm or cone.

Now that I'm earnestly researching drivers for DIY subwoofers, I've actually seen companies listing Xmax as the point to point measurement, or Xmech of the driver. Very confusing.
If there is only one measurement listed, and its labeled Xmax pp, or something like that... and it's too good to be true: It probably is!

 

[Verdinut]

Now that I'm earnestly researching drivers for DIY subwoofers, I've actually seen companies listing Xmax as the point to point measurement, or Xmech of the driver. Very confusing.
If there is only one measurement listed, and its labeled Xmax pp, or something like that... and it's too good to be true: It probably is!

You know as well as I, that many manufacturers either exaggerate or don't specify in detail their spec figures, be it for amps with regard to distortion figures, frequency response etc. and for loudspeaker specs, they have a tendency to exaggerate the frequency response, the sensitivity or omit to clearly specify the dB deviation from the average output when it comes to the low or high frequency limit.