[Vedder323]

I am playing around with the integrated subs in my Strata Minis and I was just wondering if there is any way knowing what frequency I have my crossover set to? I mean, the exact HZ. Most plate amps have a low number/high number listed but thats it... Is there a sure way of knowing the in between?

[tg3]

Is there a sure way of knowing the in between?

Yes, measure it.      
You could use free software like REW and a calibrated microphone to analyze the woofer output.

[Tyson]

Yes, a mic, a mic preamp, and a free software program like REW, or HOLM Impulse are your friends.  Do NOT trust the markings on the knob of your subs.

[HAL]

Wierd,
I thought I answered this earlier this morning, but it is gone.   

Agree with REW and a mic and mic preamp to do a nearfield measurement.  Should be easy to do.

[Danny Richie]

You'll actually need to take in room responses of each speaker to see where your room gain is. Then you can use your controls to compensate.

You might also get it real close by ear. The sub n that one should really play no higher than about 50Hz and I'd start it at just off of the bottom and work my way up a little at a time.

[Vedder323]

You'll actually need to take in room responses of each speaker to see where your room gain is. Then you can use your controls to compensate.

You might also get it real close by ear. The sub n that one should really play no higher than about 50Hz and I'd start it at just off of the bottom and work my way up a little at a time.

Danny,

Isnt the crossover in the 5'' coupler dropping off at 80hz? I would think (and forgive me I really dont know) that you would want the sub to kick in right around 80-100 wouldnt you? I believe thats what the manual was suggesting but I could be off.

[Danny Richie]

Danny,

Isnt the crossover in the 5'' coupler dropping off at 80hz? I would think (and forgive me I really dont know) that you would want the sub to kick in right around 80-100 wouldnt you? I believe thats what the manual was suggesting but I could be off.

But at the crossover point each driver must be 6db down in order for it to sum flat.

[Vedder323]

But at the crossover point each driver must be 6db down in order for it to sum flat.

Ok. I am far from an audio wiz kid but I think I understand what you mean... are you saying that if the sub is set to 80hz, that would raise the frequency curve in that range?

If this is the case, why would the manual strongly suggest to stay between 80 and 100?

[Danny Richie]

If this is the case, why would the manual strongly suggest to stay between 80 and 100?

I don't know. I didn't write the manual, I just design the crossover for it.

The Atohm woofer shows to be -3db down at 88Hz in a sealed box of that size and the -6db is 64Hz. So for the sub to be -6db down at 64Hz (including an average room gain), then the setting on the plate amp needs to be between 35Hz and 45Hz.

Peaks or dips in the room could cause some variation in that though.

[Vedder323]

I don't know. I didn't write the manual, I just design the crossover for it.

The Atohm woofer shows to be -3db down at 88Hz in a sealed box of that size and the -6db is 64Hz. So for the sub to be -6db down at 64Hz (including an average room gain), then the setting on the plate amp needs to be between 35Hz and 45Hz.

Peaks or dips in the room could cause some variation in that though.

Thanks Danny.

I decided to try REW for the first time yesterday. I dont know if I did it right but I followed the help guide as best as possible. This was the measurement I have in my room without the plate amps/subs turned on.

What are your thoughts?

[jtwrace]

adjust your scaling to 20Hz to 20K Hz first. 

[Vedder323]

adjust your scaling to 20Hz to 20K Hz first.

I think this will help?

[jtwrace]

So this is your in room FR?  The mic is placed at your ear height and the mic is pointing towards the speakers from listening position.  Right?

Also, later down the road you might want to look at waterfall plot. 

Set the scaling from ~20Hz-200Hz and 167 > 500 ms

[Vedder323]

So this is your in room FR?  The mic is placed at your ear height and the mic is pointing towards the speakers from listening position.  Right?

Also, later down the road you might want to look at waterfall plot. 

Set the scaling from ~20Hz-200Hz and 167 > 500 ms

Yes, thats correct. Using the Radioshack SPL meter as my mic.

Here is the waterfall.

[jtwrace]

I also imagine that you uploaded the generic cal file for the RS meter?

So now you have your current in room FR.  To do the speakers it's going to be different.  I'll let Danny handle that as that's his bag.  I know how I would do it...

 

[Vedder323]

I also imagine that you uploaded the generic cal file for the RS meter?

So now you have your current in room FR.  To do the speakers it's going to be different.  I'll let Danny handle that as that's his bag.  I know how I would do it...

 

Thanks JT, based on what we are seeing here, what is your suggestions for my room? Am I in "bad shape"? Its obvious there is a dip between 60-120 or so?

[jtwrace]

Thanks JT, based on what we are seeing here, what is your suggestions for my room? Am I in "bad shape"? Its obvious there is a dip between 60-120 or so?

You've got some work ahead of you if you're really wanting to get it "flat".  The dip down low will be "easy" to fix the stuff up high is really wild looking (to me). 

Have you done measurements with your subs?  That's different then what your tittle of the thread says but you may want to do that too so you know what you really have as a complete system. 

*NOTE*  I can't stress this enough.  Make sure you take really good notes and or your file names are clear.  After you get a bunch you will not be able to recall what is what.  Looking at data that you have no idea what or when it's from is worse then no data. 

[Vedder323]

You've got some work ahead of you if you're really wanting to get it "flat".  The dip down low will be "easy" to fix the stuff up high is really wild looking (to me). 

Have you done measurements with your subs?  That's different then what your tittle of the thread says but you may want to do that too so you know what you really have as a complete system. 

*NOTE*  I can't stress this enough.  Make sure you take really good notes and or your file names are clear.  After you get a bunch you will not be able to recall what is what.  Looking at data that you have no idea what or when it's from is worse then no data.

I did not take any measurements with the subs yet as I wanted to get an idea where the issues are without them first.

What would be the approach for the dip?

What would be the approach for the stuff up high?

The room is very small. 10x9x10. I have some studio foam in there right behind the couch but not much.

[jtwrace]

I did not take any measurements with the subs yet as I wanted to get an idea where the issues are without them first.

What would be the approach for the dip?

What would be the approach for the stuff up high?

The room is very small. 10x9x10. I have some studio foam in there right behind the couch but not much.

Now that you have the speakers you should do a complete system measurement as it stands. 

Personally, after that, I'd do each speaker alone. 

This is a huge amount of time...

[Danny Richie]

So is that the left speaker or the right speaker. We need to see each of them.