help with box tuning

[1two3 16]

i bought a rockford fosgate t1500bd amp and it says its subsonic filter is at 28hz.

im buying an Xcon 15 wich says to tune (optimal) 27-34hz

going to try putting it in the optimal box size of 4 cubes.

ive heard that 33hz is the best tuning frequency all around.

i listen to all types of music and i want more sq than spl.

also heard that your supposed to tune the box about 2hz higher than the subsonic filter. (gives me tuning of 30hz)

is that true? why or why not?

what should i tune my box to?

[dbsupra 69]

You set the ssf to the tuning frequency not the other way around. Although in your case being nonadjustable that isn't an option.

You usually want the ssf 1/2 to 1/3 octave below tuning frequency. Also remember the ssf is a low frequency high pass filter. It has a rolloff and won't just magically cut off at that frequency.

The reason for the ssf is because of the xmax curve. It is the lowest at tuning frequency but exponentially higher below.

[pro-rabbit 64]

Tuning is more about the vehicle application and desired results. In relative terms, when 99% of most talk about tuning, they are talking about what an enclosure would be tuned to in an open area, not inside a vehicle.

[1two3 16]

You set the ssf to the tuning frequency not the other way around. Although in your case being nonadjustable that isn't an option.

You usually want the ssf 1/2 to 1/3 octave below tuning frequency. Also remember the ssf is a low frequency high pass filter. It has a rolloff and won't just magically cut off at that frequency.

The reason for the ssf is because of the xmax curve. It is the lowest at tuning frequency but exponentially higher below.

ok thanks but ull have to explain the "1/2 to 1/3 octave below tuning frequency" in laymans terms. i have a very limited understanding about tuning

[stiffler style 9]

33hz/2 = 16.5hz (one octave down). Half octave so 16.5/2 = 8.25hz

33hz-8.25hz = 24.75hz or 25hz. So 25hz as the lowest. (Am I correct in this very simple math?)

Your amps 28hz ssf is fine.

[codester 48]

33hz/2 = 16.5hz (one octave down). Half octave so 16.5/2 = 8.25hz

33hz-8.25hz = 24.75hz or 25hz. So 25hz as the lowest. (Am I correct in this very simple math?)

Your amps 28hz ssf is fine.

So at a tuning of 32hz I should set my ssf to around 24-25hz safely? (given all other settings are correct)

[Impious 1,476]

33hz/2 = 16.5hz (one octave down). Half octave so 16.5/2 = 8.25hz

33hz-8.25hz = 24.75hz or 25hz. So 25hz as the lowest. (Am I correct in this very simple math?)

Your amps 28hz ssf is fine.

You math is correct, except you took the long way.

33 * .75 = 24.75 = 1/2 octave