Setting SSF

[528hz 10+ year member]

Can you use the same tone or frequency you use to set the gains for setting the SSF?

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[yunvme666 10+ year member]

i know theres a way, i seen someone use on here goin of the crossover db slope and the voltage change between notes or somethin like that, which theroetically sounds right......

 

[528hz 10+ year member]

yeah I know the procedure, just making sure there isn't some type of sweeping tone that I should over a regular 40 or 50 hz tone.

 

[squeak9798 5,000+ posts]

If you are trying to set it to a particular frequency, you can use a test tone of that frequency [easiest way]. Whether or not this is the same tone used to set your gain is up to you.

Turn the SSF all the way down. Unplug the subwoofers. Grab a DMM, set it to AC volts and connect it to the amp's outputs. Play the test tone and raise the volume until the DMM reads 1.414V. Then with the volume in that same position, raise the SSF until the DMM reads 1V.

Or you can just set it by ear.

What frequency are you trying to set the SSF to? What is the tuning of your enclosure?

 

[528hz 10+ year member]

Well my box is tuned to 33 hz, so if I use the equation of SSF_Voltage = 0.707*Sub_Voltage (42.42)= 29.99

29.99 is what I need to set my SSF to on the DMM, correct? Or does that seem too low?

I will use the same 45 hz frequency I use to set my gains.

 

[squeak9798 5,000+ posts]

The formula is correct.

20*log(42.42/30) = 3db

The response is the same compared to the one I posted, just different voltage levels.

However, if you use the 45hz test tone to do this, you will be setting your SSF to 45hz.

Why would you want to set your SSF to 45hz if your box is tuned to 33hz? You'd be setting your SSF a half octave above your tuning frequency. At 45hz the SSF will have attenuated the signal by 3db. And, for example, if the SSF has a slope of 24db/oct (fairly common), at your tuning frequency the the SSF will have attenuated the signal -12db.

In order to use the DMM formula method, you need to use a tone of the same frequency you want your SSF set to.

 

[SethPhillips 5,000+ posts]

im allso curious on how i would set my ssf... sorry to thread jack...

my box is tuned to 33hz...

 

[squeak9798 5,000+ posts]

im allso curious on how i would set my ssf... sorry to thread jack...my box is tuned to 33hz...

Then you can set it to 33hz (tuning), 28hz (5hz below tuning), 23hz (10hz below tuning), 24.75hz (1/2 octave below tuning), any number in between, above or below those listed.

There's so many different "theories" on what frequency to set the SSF to that you'll not find "one" right answer. The half-octave method makes since to me as you're generally safe down to around 1/2 octave below tuning before the sub begins to really unload.

You can set it by ear if you wish. Or pick a frequency and use the method above to set it to that exact frequency.

I wouldn't really recommend setting it a 1/2 octave above tuning like the OP wants to do, however.

 

[SethPhillips 5,000+ posts]

Then you can set it to 33hz (tuning), 28hz (5hz below tuning), 23hz (10hz below tuning), 24.75hz (1/2 octave below tuning), any number in between, above or below those listed.
There's so many different "theories" on what frequency to set the SSF to that you'll find "one" answer. The half-octave method makes since to me as you're generally safe down to around 1/2 octave below tuning before the sub begins to really unload.

You can set it by ear if you wish. Or pick a frequency and use the method above to set it to that exact frequency.

I wouldn't really recommend setting it a 1/2 octave above tuning like the OP wants to do, however.

thanks squek!

 

[king ranch 5,000+ posts]

so if i have a box tuned to 34hz i should just set my ssf to around 34hz and then set my gains with a 34hz test tone

 

[528hz 10+ year member]

Thank you as well Squeak.

So I'll use a 30hz tone, but shoot for a target of 29.99v. Should I set the gain or SSF first, or does it matter?

 

[yunvme666 10+ year member]

i remember when the ssf's started popin up most people where just told to use the tuning freq. yrs ago to keep out notes it doesnt need to power or some bs....lol......