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Stereo Integrity's new HT Subwoofer - Page 18

post #511 of 2212
Quote:
Originally Posted by bossobass View Post

There's the rub... assuming your sub is for soundtrack reproduction, you don't know what the signal contains until you give it a spin. Recent STs (Total Recall, Wrath Of The Titans, The Amazing Spiderman, The Dark Knight Rises, etc.) have very high level 2-20 Hz content. Run the L/T'd system for max output >30 Hz and LMK what the results is with those titles. cool.gif
Source with no content below 30 Hz is irrelevant and does not require a subwoofer of multiple 18s.

Thank you.
What happens when subwoofer is underpowered ?
Say, it takes 1000w to reproduce sub-30 hz part of the signal but the amp can only deliver 500w. Is it reasonable to expect only the parts of the signal that require power in excess of the amp limits to be clipped ? or the power gets trimmed over the full passband in such a way that the overall frequency response shape is unchanged?
Edited by zheka - 1/1/13 at 11:16am

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post #512 of 2212
Hey guys,

I should know if my order is ready by the end of today. I'm going to physically drive down to SI to pick up my (and a few other members) order and bring them back to my house in Chantilly, VA.

Is there anyone else in the area that would want me to pick up their orders for them? If you are a short drive to my house, it might save a bit in shipping costs. I figure since I am doing it for a few other people, I would extend the offer to anyone else interested.
post #513 of 2212
Quote:
Originally Posted by zheka View Post

Thank you.
What happens when subwoofer is underpowered ?
Say, it takes 1000w to reproduce sub-30 hz part of the signal but the amp can only deliver 500w. Is it reasonable to expect only the parts of the signal that require power in excess of the amp limits to be clipped ? or the power gets trimmed over the full passband in such a way that the overall frequency response shape is unchanged?

You clip the input of the amp and it distorts/compresses etc.
Edited by nograveconcern - 1/2/13 at 4:41am
post #514 of 2212
Quote:
Originally Posted by nograveconcern View Post

You clip the input of the amp and it distorts/compresses etc.

would not you want to set the gain structure in such a way that the amp is the first one to clip?

anyway, for the sake of discussion let's assume that the input signal is clean.
post #515 of 2212
Guys - I took some pictures a while back I've been meaning to share comparing the SI 18" to the Dayton - enjoy!

Notes -

  • Both are really great looking drivers.
  • SI has a meaner looking surround while the Dayton has a more substantial motor structure.
  • The dayton is a few inches more shallow.
  • The SI has a shiny black basket while the Dayton has a black powdercoat look to it.
  • Both have similar type rubber gaskets on the front.
  • SI has a paper type cone while the Dayton is aluminum.
  • Both sound awesome!!
  • In multiples, both provide ridiculous amounts of output in relatively small enclosures. Far beyond what is 'reasonable' or 'necessary' even to us enthusiasts.

Going in the box...

SI 'Backside'

Dayton 'backside'

SI

Dayton

Si top / surround

Dayton top / surround

Together

Edited by Gorilla83 - 1/2/13 at 7:11am
post #516 of 2212
Nice Rilla!
post #517 of 2212
Thanks for the pics. Mean vs. Clean...so hard to pick. biggrin.gif

Quote:
Originally Posted by zheka View Post

would not you want to set the gain structure in such a way that the amp is the first one to clip?
anyway, for the sake of discussion let's assume that the input signal is clean.

No, you want to set everything up so that all portions of the system have clean headroom (6db is ideal) at your maximum listening level. If you are asking a 500w amp to put out 1000w then you are clipping the input of the amp. IOW you are 3db beyond your systems maximum capability and 9db beyond where your system's max should ideally be set and you need to turn down.

Also, if I am going to be limited somewhere, I would prefer to have more clean headroom in my amp than clean displacement in my subs. If I can handle 500w at 20hz in my sub before running out of xmax then I want more than 500w of amp available so that I never clip the input of the amp. Power is relatively cheap.

OTOH if I can produce say 125db at 20hz w/ my subs at 500w then I only need 500w because I already have enough clean headroom for my maximum listening level.
post #518 of 2212
Quote:
Originally Posted by popalock View Post

Hey guys,
I should know if my order is ready by the end of today. I'm going to physically drive down to SI to pick up my (and a few other members) order and bring them back to my house in Chantilly, VA.
Is there anyone else in the area that would want me to pick up their orders for them? If you are a short drive to my house, it might save a bit in shipping costs. I figure since I am doing it for a few other people, I would extend the offer to anyone else interested.

I look forward to hearing from you Popa, as you know, I've ordered 4x SI's and driving to pick'em up is NOT an option for me as you are almost 1000KM's away from me.

Please keep us posted on everything, the place, the subs, the people, etc...

Thanks for everything you've done so far!

Regards,
post #519 of 2212
Nice pics, Gorilla. Sure gets me excited for mine. smile.gif
post #520 of 2212
Quote:
Originally Posted by nograveconcern View Post

No, you want to set everything up so that all portions of the system have clean headroom (6db is ideal) at your maximum listening level. If you are asking a 500w amp to put out 1000w then you are clipping the input of the amp. IOW you are 3db beyond your systems maximum capability and 9db beyond where your system's max should ideally be set and you need to turn down.
Also, if I am going to be limited somewhere, I would prefer to have more clean headroom in my amp than clean displacement in my subs. If I can handle 500w at 20hz in my sub before running out of xmax then I want more than 500w of amp available so that I never clip the input of the amp. Power is relatively cheap.
OTOH if I can produce say 125db at 20hz w/ my subs at 500w then I only need 500w because I already have enough clean headroom for my maximum listening level.

I followed these instructions for the gain structure set up.

So what happens with extreme ULF content most subs/amps cannot come close to reproducing even if there is enough headroom at 20Hz ?
post #521 of 2212
The assumption is that program material that is below 20hz will be nowhere near the max for the lfe channel.
post #522 of 2212
Quote:
Originally Posted by nograveconcern View Post

You clip the input of the amp and it distorts/compresses etc.
Clip the output for sure. Clipping the input is much less certain.

Quote:
Originally Posted by nograveconcern View Post

The assumption is that program material that is below 20hz will be nowhere near the max for the lfe channel.
Which is all well and good until you find a movie where that isn't the case. Hopefully you don't damage anything in the process. And frankly, I'm not sure that is the case even now with some of the crazy stuff in movies like the pod emerging scene in WOTW.
post #523 of 2212
Quote:
Originally Posted by nograveconcern View Post

The assumption is that program material that is below 20hz will be nowhere near the max for the lfe channel.

There are spectrograms of well know titles with 3Hz content at -10dBFS. And that' s after the output signal roll off the player would have at the frequency .
post #524 of 2212
Quote:
Originally Posted by Stereodude View Post

Clip the output for sure. Clipping the input is much less certain.
Which is all well and good until you find a movie where that isn't the case. Hopefully you don't damage anything in the process. And frankly, I'm not sure that is the case even now with some of the crazy stuff in movies like the pod emerging scene in WOTW.

Quote:
Originally Posted by zheka View Post

There are spectrograms of well know titles with 3Hz content at -10dBFS. And that' s after the output signal roll off the player would have at the frequency .

Right, there are always exceptions as so many are quick to point out, so you either go all notnyt/japandave and build for it or pay attention to your program material, know your limits and turn down when playing the stupid low stuff. Unless you find some kind of variable frequency limiter there is no guarantee that you won't damage anything.

That said, I would still set up stuff so that the subs go non-linear before clipping the amp. I can listen for subs farting out and turn down that way. Others may do things differently, but I've always favored clean headroom in my amps. Power compression of the coil and the non-linear resistance of the suspension at extreme excursion make it fairly safe, in terms of mechanical damage to the spyder, to have a little extra headroom.

Re input vs output, stereodude has a better grasp of that stuff than I. If you run out of headroom the amp clips. tongue.gif
post #525 of 2212
Sweet, just got the tracking notice that my 7 babies have shipped. biggrin.gif
post #526 of 2212
Quote:
Originally Posted by bass addict View Post

Sweet, just got the tracking notice that my 7 babies have shipped. biggrin.gif

7? You making a septogon?
post #527 of 2212
Quote:
Originally Posted by beastaudio View Post

7? You making a septogon?

LOL. No, I ordered 6 18's and 1 15 for the heck of it.

I should have ordered 8 so I could have called it Octapussy to go with Rillas Big O. biggrin.gif
post #528 of 2212
Quote:
Originally Posted by bass addict View Post

LOL. No, I ordered 6 18's and 1 15 for the heck of it.
I should have ordered 8 so I could have called it Octapussy to go with Rillas Big O. biggrin.gif

That's my big O foo. haha good luck, I may just have to drive down to SI tomorrow, I don't think I will make it until Saturday...
post #529 of 2212
Quote:
Originally Posted by beastaudio View Post

That's my big O foo. haha good luck, I may just have to drive down to SI tomorrow, I don't think I will make it until Saturday...

Oops, lol.

I better get started working on my cab. My second 4000 is due in Friday and the subs will be here next week. I just need to decide if I want to start with 4 or 6. I like the tower of 6 idea, even though you won't see it behind my screen wall, I'll know it's there. smile.gif
post #530 of 2212
What can these drivers handle in a sealed setup? Say a DO box like gorillas with the Dayton's? He has 1250 watts to each driver. Are the SI's as capable with less driving it? Would a EP4000 be enough to drive 2 to max levels should I still be looking at a clone or other more powerful amps ( CV or crown)
post #531 of 2212
ep400 for two, crown5000 or cv for 4, clone for 8. nuff said smile.gif They don't need as much as the HO's to get going, very compliant, but sealed they can still take 1000 watts and be fine in smaller boxes (4-4.5 cuft)
post #532 of 2212
Dilemma resolved
Edited by Aaron Smith - 1/2/13 at 8:07pm
post #533 of 2212
Mine and my brother's will be arriving in Richmond, VA tomorrow. biggrin.gif
post #534 of 2212
Thanks beast that's what I was looking for
post #535 of 2212
So for a single driver in a sealed enclosure, I hear 4.5-6 cu ft - go larger with less power. I'm going to make one of these as an 'end table', something like a 24" cube on small legs, downfiring. Plenty of bracing and the driver would bring volume down below 6. The idea is bang-for-the-buck. I'll make one to start (first DIY speaker), see how I like the output, and probably add another when funds allow.

What would be the most cost-effective way to sufficiently power the SI 18 in such an enclosure? I was originally recommended a 500w yung plate amp for $200, but I'm wondering if that wouldn't be enough power?
post #536 of 2212
It should work pretty well, but you'll want to mod the amp to lower the high pass filter to something like 5 to 8Hz and bypass the boost circuit. In 6ft^3 (170L) you can only put ~500W on the driver without exceeding xmax (with a 5Hz HPF).
post #537 of 2212
just get the behringer ep4000 and have the other channel as backup when you inevitably build the OTHER endtable smile.gif they are about $275 right now from Walmart last I looked.

Get dual 2 ohm voice coil config and you can run them stereo 4 ohm and be golden at a little over 650 watts per driver once all is said and done
post #538 of 2212
stereodude's suggestion is also good, or you could just drop the box size a shade and be comfy with 650watts
post #539 of 2212
Quote:
Originally Posted by beastaudio View Post

stereodude's suggestion is also good, or you could just drop the box size a shade and be comfy with 650watts

Guess what Fed Ex just dropped off?
post #540 of 2212
Quote:
Originally Posted by robertcharles View Post

Guess what Fed Ex just dropped off?

Pics or it didn't happen!!!!!!!
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