SVS Subwoofer: Cylendrical v/s Box

Lowell_M

Holydoc wrote:

Doh! I just noticed this. So if you were not upset at IronMike, then I have turned into the guy whose dog you kicked?

For the life of me, I could not find anything offensive that I posted.

I was talking about SKsolutions trying to whoop on Sid.

Dr. Spec

Ron Temple wrote:

Hey Ed,

Have you had a chance to listen and compare the new driver's yet?

No, but my former PB2+ is still floating around locally and the new owner will be ordering two 12.3 woofers for it when they go on sale. We'll do the install and see how they sound.

Holydoc

Dr. Spec wrote:

No, but my former PB2+ is still floating around locally and the new owner will be ordering two 12.3 woofers for it when they go on sale. We'll do the install and see how they sound.

I have not even looked to see how hard a speaker swap out will be on the PB12/plus. I would like to get the 2-3db increase that the 12.3 version offers. Is this swap out something that anyone can do without messing up an already great thing?

Sorry if this is a stupid question. I am just in fear of messing up my SVS by trying to improve it.

Dr. Spec

Vr3MxStyler2k3 wrote:

When I saw Doc post, I thought I might be in for a verbal beat down, but I am pleasantly surprised. Cool.

I based my bracing assessments on what Tom and co. have said about their enclosures, that since they were 1" thick stock, they didnt need the bracing.

Ive seen the internals (pictures) of the ISD 2 and all it had was a middle x brace - which to me isnt enough. But I like overkill anyways.

Dosnt change the fact they are top notch either way.

Sid you are largely past the point of needing (or deserving) verbal beat downs........a few years ago - sure, different story.

It's not so much the panel thickness on an absolute basis, as the panel thickness relative to the unbraced surface area. This dictates flex potential under pressure and also the panel's resonance frequency.

If you like overkill, you'll like this pic........Triad Gold InRoom PowerSub enclosure. The opening in the rear is the amp cut-out.

Dr. Spec

Polkmaniac wrote:

Just to give you an idea of what their biggest cylinder looks like in a typical room...

I went with a cylinder because, as you can see, floor space is limited at the front soundstage, and the box sub that is the equivalent of that 16-46 wasn't going to fit anywhere in that room.

I'm thinking a little symmetry is never a bad thing..........how about another on the left?

Dr. Spec

Holydoc wrote:

I have not even looked to see how hard a speaker swap out will be on the PB12/plus. I would like to get the 2-3db increase that the 12.3 version offers. Is this swap out something that anyone can do without messing up an already great thing?

Sorry if this is a stupid question. I am just in fear of messing up my SVS by trying to improve it.

Takes about 20 minutes - all you need is a screwdriver and a helper to hold/disconnect the woofers. Sometimes you need to tilt the cab a bit to get one started and then you can get your fingers under the basket edge.

SKsolutions

a_mattison wrote:

Sid, Did you kick that guy's dog or something?...Steal his girlfriend?

Your explaination makes perfect sense.

No, it's just the incessant and unintelligible yammering I can't take. To try to explain something you must first understand it, not just read the Cliffnotes. I don't care if the "jargon" is icorrect, but don't try to explain something in an oversimplified and quick rant like it's the definitive word. Life must be so stresfull hawking teenagers their DJ equipment.

VR3

Blah Blah Blah

Dude, get over yourself.

Lowell_M

SKsolutions wrote:

So, if I'm reading this right, it has nothing to do with standing waves, frequency length, enclosure absortion, cone damping, or resonant frequencies. Cool, I'll buy a Radio Shack sub and strap some guitar frets to it. Maybe some strings too.

...Talk about yammering and jargon.... In the context of the point being made there was no need for your additional jargon. Simple fact is..they were talking about sub box shapes and the need for bracing in a box due to the fact that the box can and will flex due to pressure exerted on the walls. Thus, causing air and sound to move differently in the box and make things sound weird...etc. A cylinder will not flex in this manner...etc, etc etc... I found it interesting since I have never considered the magnitude of the pressures that are fluctuating inside that box.

Lighten up.:eek:

SKsolutions

a_mattison wrote:

...

Thus, causing air and sound to move differently in the box and make things sound weird...etc. A cylinder will not flex in this manner...etc, etc etc... I found it interesting since I have never considered the magnitude of the pressures that are fluctuating inside that box.

I was speaking of yammering, yes. I did not, however, pontificate on it's propensity to propagate, but I was sure someone would avail themselves to it. I especially appreciate sentences that begin with "Thus,", and the use of the ubiquitous "weird" to quantify complex systems.

Like Xenon

Cheerio-

VR3

Look...

I know your just itching in your britches to get this thing out. Why dont you just tell us how this works the "correct" and "professional" way so youll just shut the heck up.

People like you annoy me, because you can spend 2 hours telling someone about something with all your correct terms - words that, if you havnt figured out - no one understands. Are you bilingual? Well, Im not - when a spanish speaking person comes in the store to buy something and cant speak english - I dont understand a freaking word he says.

Its not much different than you telling a beginner to HT/Audio how an enclosure reacts to the woofer.

So put down the tape measurer, stop trying to compare and contrast yourself over the internet and realize that no one is that interested in the subject to go that deep into it. And if they are, they have the whole wide internet to go through to obtain it. I doubt they will need you to explain it to them.

But I'm sure thats what you would like.

Lowell_M

SK put some thought into that last one. Excellent use of 'P' words. Must be the mostest smartest guy ever.

Starting sentences with "Thus" and ending in "weird" is my favorite. Actually, ending the sentence with "weird" was my way of just finishing the sentence because I realized I was wasting my time.....OH..here goes more of it...weird....

mrbigbluelight

SVS subwoofers.

Now, as the proud owner of an Athena AS-P4000..

......Hey ! Where do you think you're going ? Sit back down !!

....I feel I am emminently qualified to speak on the subject. Or not.

The point I would make is that ANY flat surface will bow when pressure is put on it. Put a 10-foot 6x6 across your back deck, stand on it, and it will bow.
Not much, mind you, unless you've been hitting the potatoe chips too heavily, but it will flex under the additional pressure.

The duct work that comes off your furnace at home is flat. To keep it from flexing excessively when the blower comes on (adding pressure to the inside of the duct work), sheet metal workers put the flat sheet in a brake and cross-crimp it (make a slight x). Works the same as bracing, and reduces sheet metal pop (noise) greatly.

My point/question would be this: although you may not see any obvious visible cross-bracing inside a subwoofer's enclosure, doesn't mean it's not there.

"Huh" ?

Is the wood on the inside of a Stradivarius violin planed flat (smooth) ?
Nope.
It has various thicknesses, strategically placed at one point by a craftsman who had his stuff together. How this craftsmen performed his art/magic still isn't exactly understood, but the result is this:

The extremely minute differences in thickness allows extremely fine differences in flexing on the soundboard that (among other factors) gives a Stradivarius violin its unique qualities.

Perhaps this method of varying wood thickness can be used as a bracing method inside a audophile level subwoofer. Using the sheet metal analogy, the equivalent of a "crimp" could be made by planing/routing a crimp (or "x") across the interior surface.
This would provide additional "bracing" that is not readily visible to the naked eye. Help to break up any sound-induced surface roll if you will.

Well, now that I've succeeded in boring you snotless, I shall retire.

I have to get back to researching HSU and SVS subbies. My daughter and son-in-law are having their 2nd anniversary in a month and a half, and I'm putting together a HT for them (so they can get rid of their Ensignia system).
Got everything but the subbie and the center.

P.S. a cylinder also flexes, but....perhaps anther time.