Fs Vs Fr

[nismos14 5,000+ posts]

Looking at some subs and here are my questions:

Listed FR is 10hz-400hz the FS was somewhere in the 40hz range.

Can someone explain to me why the FS is so much higher than the lowest part of the FR? I always thought the FS was relatively close to the lowest part of the FR.....

How does this particular drivers parameters affect performance?

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[nismos14 5,000+ posts]

Anyone?

 

[Warbleed 10+ year member]

Fs does NOT tell you the lowest frequency that the driver will PLAY. It tells you the Free Air Resonance of the driver. FR is Frequency Response, and is thus a rating for frequencies the driver can play.

Sometimes they specify tolerances (i.e. +/-3dB) as well. Sometimes these are fairly honest, and sometimes they are not at all honest. You have to bear in mind Fs is a DRIVER parameter, and realistically FR is a SYSTEM parameter (driver + enclosure + environment) and thus the two often will vary considerably, even if both are being given honestly.

 

[nismos14 5,000+ posts]

So in this particular driver, I can expect a different FR based on application (obviously) but if I were to utilize this driver as an IB driver how does the FS affect that? Can I expect the driver to produce good output below the FS?

 

[Warbleed 10+ year member]

So in this particular driver, I can expect a different FR based on application (obviously) but if I were to utilize this driver as an IB driver how does the FS affect that? Can I expect the driver to produce good output below the FS?

Yes, it will most likely go well below Fs in an IB application. In car applications, most drivers in an IB configuration shouldn't have any trouble going below 20Hz, even with an Fs in the 30s.

 

[nismos14 5,000+ posts]

Can I expect it to reach down into the lower depths of its FR WITH some authority?

 

[bass_lover1 10+ year member]

Not like this is that important, but at Fs, the driver's impedance will be highest.

 

[Warbleed 10+ year member]

Can I expect it to reach down into the lower depths of its FR WITH some authority?

Assuming the specs are honest, yes it should.

 

[nismos14 5,000+ posts]

Hey thanks man. On a side note, I used to go to Des Moines all the time when I lived in IA. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[Warbleed 10+ year member]

Not many other places to go really. Iowa City is pretty cool, most of the other cities blow. I lived in Ames while I went to college, but I was happy to leave that place.

 

[nismos14 5,000+ posts]

Haha, I bet. I was happy to come back home after living there a year.