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So last night we were on a gig in a particularly nasty untreated room, tall vaulted ceilings, 600 capacity space, just a really awful place for subwoofers or speakers of any kind, and after sliding the subs around we came to the conclusion that the corner was the best place for them. Well we wrote an invoice for 8 subs so by god we are using 8 subs the resulting frequency response was pretty wild. We set the hpf to 30hz 4th order Butterworth and it was kissing 20hz. This was unequalized response from the FOH area. That poor building was fighting for it's life and the stack was hardly working at all. I mean I walked into this wondering how low you could really go with titan horns and the answer is 20hz I guess damn that hit like a freight train. The music was all deep dubstep, leftfield bass, neurofunk, the stuff that actually does extend below 30hz and my god did that monstrosity prove a point. There was a couple times where the harmonics extended below my range of hearing which I found to be a wildly interesting effect at that spl I would be scared to be in a room with that anywhere near it's maximum output LOL

Reading along with a big shit eating grin on my face, trying to contain the emotions welling up from within, like the final hero scene of a Disney film. When, as a man, you don't want anyone else in the room/theater to know your emotions have been stirred the least... and a little something escapes the mouth, a little noise I wasn't able to contain within, a meep. In an effort to restore any man dignity I play it off as though it was a burp, stretch my arms, clear my throat, say something in a deeper tone than usual.

I'm always impressed with the lengths you guys go to get it as right as it can be. Placement, measurement, taking into account venue challenges, and tuning to overcome them. I'd bet you guys are working these gigs with way more applied knowledge than any of your direct competitors. Keep it up, I thinks it's going to pay out well for you guys.

Thanks, as always, for the detailed gig report and photos

That poor building.

IIRC, 4th order Butterworth is 24dB/octave.
So your readings are a little higher than what you would expect.
It's still great to see that result though.

Nice!

Seth wrote: ↑Sat Sep 23, 2023 8:16 pm Reading along with a big shit eating grin on my face, trying to contain the emotions welling up from within, like the final hero scene of a Disney film. When, as a man, you don't want anyone else in the room/theater to know your emotions have been stirred the least... and a little something escapes the mouth, a little noise I wasn't able to contain within, a meep. In an effort to restore any man dignity I play it off as though it was a burp, stretch my arms, clear my throat, say something in a deeper tone than usual.

I'm always impressed with the lengths you guys go to get it as right as it can be. Placement, measurement, taking into account venue challenges, and tuning to overcome them. I'd bet you guys are working these gigs with way more applied knowledge than any of your direct competitors. Keep it up, I thinks it's going to pay out well for you guys.

Thanks, as always, for the detailed gig report and photos

That poor building.

Yup.

Grant Bunter wrote: ↑Sat Sep 23, 2023 9:02 pm IIRC, 4th order Butterworth is 24dB/octave.
So your readings are a little higher than what you would expect.
It's still great to see that result though.

You are correct but I do believe Butterworth is -3db at the crossover point LR is -6db. When you sum two Butterworth filters there will be added gain at the crossover frequency that may or may not need to be balanced. I think what's happening here is the stack is still horn loaded down to below 30hz in this configuration and the 24db filter is merely attenuating 20-30hz before it actually rolls off. I don't have a sim of the t48 so it's hard to determine where xmax would be exceeded with this much horn. 30hz is plenty fine it seems though It would have been pretty neat to try shifting hpf to 25 or 20hz and seeing how it effects the low corner but I was pretty strapped for time.

Seth wrote: ↑Sat Sep 23, 2023 8:16 pm Reading along with a big shit eating grin on my face, trying to contain the emotions welling up from within, like the final hero scene of a Disney film. When, as a man, you don't want anyone else in the room/theater to know your emotions have been stirred the least... and a little something escapes the mouth, a little noise I wasn't able to contain within, a meep. In an effort to restore any man dignity I play it off as though it was a burp, stretch my arms, clear my throat, say something in a deeper tone than usual.

I'm always impressed with the lengths you guys go to get it as right as it can be. Placement, measurement, taking into account venue challenges, and tuning to overcome them. I'd bet you guys are working these gigs with way more applied knowledge than any of your direct competitors. Keep it up, I thinks it's going to pay out well for you guys.

Thanks, as always, for the detailed gig report and photos

Thanks Seth it's an honor for real. The market out here is full of mix engineers but not a whole lot of passionate system techs. We frequently get comments about the sound quality, level of care, and attention to detail. And we are frequently told by promoters that we are the best in our market sector. It's made it very easy for us to get gigs most might not get with a diy rig. For example one of our recent clients is a very well known luxury car manufacturer that rhymes with gently we set off like 20 car alarms whoops.

Wylandright206 wrote: ↑Sat Sep 23, 2023 9:46 pm
You are correct but I do believe Butterworth is -3db at the crossover point LR is -6db. When you sum two Butterworth filters there will be added gain at the crossover frequency that may or may not need to be balanced. I think what's happening here is the stack is still horn loaded down to below 30hz in this configuration and the 24db filter is merely attenuating 20-30hz before it actually rolls off. I don't have a sim of the t48 so it's hard to determine where xmax would be exceeded with this much horn. 30hz is plenty fine it seems though

A 4th order BW is 2 x 2nd order BW filters cascaded, but the arrangement of caps and resistors is altered in the cascaded section, and I think sums flat.

Wylandright206 wrote: ↑Sat Sep 23, 2023 9:46 pm It would have been pretty neat to try shifting hpf to 25 or 20hz and seeing how it effects the low corner but I was pretty strapped for time.

Errr why?
You already have measureable 20Hz. When pushing the driver below Fs the driver is rapidly increasing in excursion, which means you reach Xmax faster.
You would have to lower your voltage limit to not blow drivers...

Wylandright206 wrote: ↑Sat Sep 23, 2023 9:46 pm It would have been pretty neat to try shifting hpf to 25 or 20hz and seeing how it effects the low corner but I was pretty strapped for time.

Errr why?
You already have measureable 20Hz. When pushing the driver below Fs the driver is rapidly increasing in excursion, which means you reach Xmax faster.
You would have to lower your voltage limit to not blow drivers...
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For science. Would not actually use that in a show setting. And I mean to be fair in the past we have absolutely used the titans like that. Lower voltage limit on a huge stack with excessive headroom run a bit lower than normal. When you have that many subs you can sacrifice some output. It really just depends on the music being played. Only drivers I've blown have been from accidently slamming a titan by itself in the workshop and one had a glue failure early on. Knowing the limits of your tools means you can take them as far as they'll go.

Feckin' beautiful!
What an imposing stack of Titans. My wife would kill me if I built more. I'd have to actually take up DJ-ing to cover my addiction...
Keep up the great work!

Good job! Now you just need to build 8 more! lol

If there was any horn I'd be okay with moving 16 of it would be the t48. Most of our boxes were made with radiata pine too so they are exceptionally lightweight. Also they smelled phenomenal the first 2 years we had them time and time again this rig reminds me why I love it.

I'd also like to add, for those of you who were wondering if you should add wheels on the mouth side, or if you should leave that corner on, the answer is remove the corner and don't add any wheels. Because look at this it's frickin beautiful. It scratches some primal itch I didn't realize I had.