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Had nothing to do with the operator? :innocent:


and it's on a junk, hand me down camera that I've never used before.
ya, im sure there were lots of things a user could do to cause a camera mic to distort the sound , lower the resolution, and use a less than desireable refresh rate.... i've made lots and lots of vids with numerous cameras over the years, ive learned that they vary quite a bit. when youre recording something that moves back and forth 30 times per second ... a lot of cameras sample every 10th of a second er sumthin
 

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Discussion Starter #122
Ryan, chill brother, I'm just messin with ya! Look at the $%^ video I posted above. :eek:

I only jest about this because it drives me nuts that 98% of the people who complain about the hardware, probably never read the manual to learn how to actually use the hardware...that, and I truly hate when people see my nice photos and say "wow, you must have a nice camera". In which I usually respond "Of course, it's floats around and takes all the pictures by itself, I have absolutely nothing to do with it".
 

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LR, that looks awesome! Surprisingly flat way down low for a sealed box. It would be cool to see some full range plots with your setup. Your LCR channels look very interesting as well. What are they?

My only concern is that it looks like the sub is so big it's blocking your left channel speaker!
 

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I think your vid was pretty good, great song selection... I just received it from sub junky myself.

The sub looks like it moves effortlessly, I've been waiting to see such a huge cone to dispel the notions in my mind that it will have trouble lol.

Were you pushing it to it's limits? Maybe it is the surround that's capable of 60-70mm only going out to 30-40mm, because it looked like it wasn't really getting going.

What's the vibration at the very end of the video when it really scoots?
 

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Discussion Starter #125 (Edited)
LR, that looks awesome! Surprisingly flat way down low for a sealed box. It would be cool to see some full range plots with your setup. Your LCR channels look very interesting as well. What are they?

My only concern is that it looks like the sub is so big it's blocking your left channel speaker!
The sub, in it's "on it's side a table" form only partially blocks the woofers on the mains. I'm not worried about that since I have the mains rolled off at 80Hz THX.

I'll see about taking some full range plots when I can find more time.

As for what the mains are...they are Elemental Designs US-6T6. They are OK for the money, but I'm hesitant to recommend Elemental Designs, as I had a very lack-luster customer experience when I received the speakers, poorly packaged, and clearly damaged BEFORE shipping (the shipping boxes were in perfect condition, but speakers and cabinets were physically damaged). In fact, one of the speaker cabinets is still damaged, and after nearly a dozen calls to Elemental Designs, I simply gave up trying to deal with them. They might have some nice hardware, but they've lost me for big purchases.


I think your vid was pretty good, great song selection... I just received it from sub junky myself.

The sub looks like it moves effortlessly, I've been waiting to see such a huge cone to dispel the notions in my mind that it will have trouble lol.

Were you pushing it to it's limits? Maybe it is the surround that's capable of 60-70mm only going out to 30-40mm, because it looked like it wasn't really getting going.

What's the vibration at the very end of the video when it really scoots?
Yeah, I posted the "Clubbed to Death" video in Sub_Junky's build thread, it's been one of my favorites for quite a while now...though You Tube neutered it with compression for a while. I wrote the guy who posted the video, since he obviously supplemented the bass on the track and added the graphics, and I asked if he could do any more. I also sent him a link to this thread in hopes he might join and post. I have a feeling his videos, as simple as they are, would be popular around these parts.

I don't think I was pushing the sub to it's limits. But I'm not sure. I'm afraid of bottoming it out...I'm really not sure how dangerous that is to the sub, if it can take an accidental hit once or twice, or if I should avoid bottoming at all costs. Plus, all this messing around with levels and inputs/outputs to get REW to work, I mucked up the levels I had set that were working so well. So once I'm sure I have the final position for the sub, I'm going to rework all the levels and see that I get the most out of it, while still blending with the mains.

As for the vibration at the end of the video...well, that would probably be the whole house! LOL

The video does a big push at 27 and 21Hz, and the kitchen, my projection screen, the floor, and ceiling resonate pretty well. My fiance jokes to people at work that her "kitchen has a sympathetic resonation at 21Hz" because of this video. I'm actually going to need to velcro the floating screen to the wall, as the new sub vibrates the screen on it's french cleat. In fact, I'm wondering if I can stuff the back side of it with mineral wool and kill two birds with one stone....:dontknow:
 

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I have a feeling his videos, as simple as they are, would be popular around these parts.

I don't think I was pushing the sub to it's limits. But I'm not sure. I'm afraid of bottoming it out...I'm really not sure how dangerous that is to the sub, if it can take an accidental hit once or twice, or if I should avoid bottoming at all costs. Plus, all this messing around with levels and inputs/outputs to get REW to work, I mucked up the levels I had set that were working so well. So once I'm sure I have the final position for the sub, I'm going to rework all the levels and see that I get the most out of it, while still blending with the mains.

As for the vibration at the end of the video...well, that would probably be the whole house! LOL

The video does a big push at 27 and 21Hz, and the kitchen, my projection screen, the floor, and ceiling resonate pretty well. My fiance jokes to people at work that her "kitchen has a sympathetic resonation at 21Hz" because of this video. I'm actually going to need to velcro the floating screen to the wall, as the new sub vibrates the screen on it's french cleat. In fact, I'm wondering if I can stuff the back side of it with mineral wool and kill two birds with one stone....:dontknow:
I'll be running these songs in my car, I need more sub 30Hz material to play with!

Yeah, it doesn't look like it's nearing its limits, looks like it has quite a ways to go, but there's so many factors that could create illusions from my end... for one, it's a 21"! Then the surround that has so much more potential.

I know what you mean about worrying, what gets me is it's supposed to take quite a bit to get the 18" from its 32mm Xmax out to its 40mm Xmech with the suspension really getting tight. So being a 21" and in a sealed enclosure, youd think an EP2500 just wouldn't do it.

But I know how it is to map it all out in your head then get to real world... CLANG!
 

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I'm shocked that you are getting that much gain, I just don't understand where it can be coming from, but more power to you. Try taking another FR up to 150hz with your main speakers in play. If that comes out looking half as nice, I would erase all thoughts about purchasing an EQ system.
 

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I'm shocked that you are getting that much gain, I just don't understand where it can be coming from, but more power to you. Try taking another FR up to 150hz with your main speakers in play. If that comes out looking half as nice, I would erase all thoughts about purchasing an EQ system.
Big sealed box that rolls off slowly. If I'm reading that graph right, that is 9dB @ 10Hz of cabin gain. He is probably pressurizing the entire space and getting some gain even though it is an open floor plan. Some of that might be measurement error, the near-field measurement should be smoother but his extension is good enough for any reasonable person.

Don't worry too much about over-excursion. It should make some noise as you near the limits. You mainly would need to be careful if you had >3000W on tap and tried some program material with huge low frequency spikes. These overload gracefully (if there is such a thing) so unless you get really stupid, the driver should handle it without a problem.

Sometimes you get lucky and have a room/setup that comes out like that. I'd get some more measurements at different locations though just to get some scope of what is going on around the listening chair. If that is a good measurement, thank the audio gods and move on to other things.

Kevin Haskins
Exodus Audio
 

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Discussion Starter #130
I will get some more measurements, thanks for your guidance Kevin.

Thanks for your input Steve, I'll follow up there as well. I did have a quick full system FR, but I didn't save it. Since I didn't take my time taking the measurement, I figured I'd discard it and come back to it when I do have time to make sure it's right.

I'll post results over the weekend. Thanks for the guidance and extra sets of eyes on this everyone.
 

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EQ is for peaks only, with a null it's a wave cancelation from room reflections and no amount of boost is going to fix that. (although another sub can help smooth things out) :devil:
Room placement of the sub can help smooth things out as well...Lonely Raven, Hoist that thing up onto your couch and use the crawling for bass method. I'm sure you can squeeze that sub just about anywhere once you find the ideal spot:dontknow:

Great thread and thanks for posting the vid, that was fun. 21" subs are cool.
 

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Remarkable build and awesome accomplishment with a sealed sub. :hail:

A few questions...

What were the final dimensions?

Are you using a HPF?

What will you charge me to build two of the boxes ready for the drivers to be mounted? :bigsmile:
 

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As for the vibration at the end of the video...well, that would probably be the whole house! LOL

The video does a big push at 27 and 21Hz, and the kitchen, my projection screen, the floor, and ceiling resonate pretty well. My fiance jokes to people at work that her "kitchen has a sympathetic resonation at 21Hz" because of this video. I'm actually going to need to velcro the floating screen to the wall, as the new sub vibrates the screen on it's french cleat. In fact, I'm wondering if I can stuff the back side of it with mineral wool and kill two birds with one stone....:dontknow:
I can't believe I forgot my favorite part:

My fiance jokes to people at work that her "kitchen has a sympathetic resonation at 21Hz" because of this video.

LOLZ that got me all over again, meant to comment on it last time

Great thread and thanks for posting the vid, that was fun. 21" subs are cool.
X2, thank you very much for taking the time to record and share the entire build to now process

Remarkable build and awesome accomplishment with a sealed sub. :hail:

A few questions...

What were the final dimensions?

Are you using a HPF?
X2 again :)
 

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Discussion Starter #134
Honestly, I've not taken, nor did I calculate external dimensions. My thing was that I build this "bass on primes". The internal (airspace) dimensions are 41" X 37" X 23", which are all primes. the bracing on the inside is all done on primes as well, with no dimensions being doubled or divisible by half.

I currently have no HPF, Kevin said one was not needed with a sealed build, though I've clipped my amp once and I started to hear some noise from the driver during early sweeps before I figured out there was a feedback loop in the sound card. Once I get everything measured a few times more, and my levels sorted, I don't believe I'll need a Low Pass Filter. Eventually I'd love an amp that delivers better at low frequencies, but as it stands now, I'm very happy with this setup. I've said before, even TV shows have more impact and depth. I'm enjoying every built of the results, and they can only get better with some tweaking.

I'll work on getting some more measurements tomorrow (Sunday). While I can't put the sub in my seating location and move the microphone around (easiest way of finding best location), I will make the efforts to tumble the sub around and take measurements. I'll repeat the near field measurement, and do some full system measurements just to prove or disprove my earlier measurements.
 

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Please define good excursion vid?
lol I'm sorry! Let me just ask this, do you think you reached the driver's Xmax in this vid? If so, then illusions are taking effect. It looks like it gets out to about 1/2 its capability. This can very well be the case due to 1: Sd illusion... 8" and 10" "subwoofer excursion" can look very extreme even when it's not, while 18" drivers can look very tame even when not 2: surround... when the surround is being stretched to the max, it looks big, when its barely being used up, it looks small. This surround/cone is designed for the Sicko-X with 60 or 70mm Xmech whereas the MX is 40mm... surround has either 20 or 30mm left to go. I can PM you a couple links that would clear it right up ;)

not tryin 2 get on your nerves here.. you have what I want, and I am getting a better idea of what mine is going to be from watching yours ;)
 

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Discussion Starter #138
I really have no idea how much more mechanical movement I have left. Besides trying to measure the the mechanical movement while running sweeps, I really am not sure how I'd know if I was at the end of it's travel or not...and I'm not looking to bottom out the driver as well.

I will see what I can do though. I still have some tweaking to do.
 

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Hi there,

What is the name of that song. I know it but I can't remember for the life of me what it is called.

Great sub by the way!

cheers

graham
 
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