Sealed box for Mule????

[mulester7]

.....ok, listening chamber is 14X20X8....two B12-Plus/4's, one in each corner of the front....two 2-way 40 inch tall front mains sitting one each, on a B12....mains have 1 inch soft dome tweeters, 8 inch woofers, and transmission lines....mains image at about 58 inches from the floor sitting on the B12's....seek small cannons to be positioned just inside the B12's, about 18 inches off the floor on a skeletal stand of 2x4's, and the inside-side subwoofer element of the B12's will fire through the skeletal 2X4 stand the small cannons are sitting on....the small cannons will be cut from 50 down, and probably around 130-150 on top....the volume of the small cannons will be brought up against the mains until they are actually balancing the mains, then I will bring up a little B12 under the small cannons....there will be the critical balance for no mud, along with no mud coming from phase lapovers between the two lows....I have two-way rears full-range also, but will leave them out of it until correct balance and no mud comes from the front....maybe, haha.....

 

[mulester7]

I'm 99.9% certain Mule has 2 of those crates they call subs, but I don't know for sure if he's running one or two Crown K1 amps. His sheetrock in that room must be falling apart.

.....Buck, each B12 is being pushed by a strapped K2, and I don't listen to stuff at sheetrock cracking levels....I may grab about 10 seconds of "really loud" sometimes, but I honestly maintain moderate levels about 95% of the time.....you can't beat headroom on any speaker really, but especially on a sub....and guys, I can't act flootey over having two B12's....Tom made it possible....

 

[WmAx]

.....ok, listening chamber is 14X20X8....two B12-Plus/4's, one in each corner of the front....two 2-way 40 inch tall front mains sitting one each, on a B12....mains have 1 inch soft dome tweeters, 8 inch woofers, and transmission lines....mains image at about 58 inches from the floor sitting on the B12's....seek small cannons to be positioned just inside the B12's, about 18 inches off the floor on a skeletal stand of 2x4's, and the inside-side subwoofer of the B12's will fire through the skeletal 2X4 stand the small cannons are sitting on....the small cannons will be cut from 50 down, and probably around 130-150 on top....the volume of the small cannons will be brought up against the mains until they are actually balancing the mains, then I will bring up a little B12 under the small cannons....there will be the critical balance for no mud, along with no mud coming from phase lapovers between the two lows....I have rears full-range also, but will leave them out of it until correct balance and no mud comes from the front....maybe, haha.....

Mulester, the solution is then simple: a proper active crossover, at about 85-100 Hz range, at least 24 db/octave rate, low passing the subs, high passing the mains. The possible issue may be found with the very large cabinet size of the subs[not the fact that they are ported, as I mentioned earler]. If SVS did not use sufficient internal wave dividers or very substantial internal acoustic dampening, then resonances will occur that will cause loss of clarity/coloration in the lower midrange/midbass when using subwoofers with cabinets of these dimensions into the upper bass/midbass range. If they do indeed cause this problem, then you would have to use another set of stereo subs as I suggested, but bandpassed to the 45-100 range, as as an example. Use of a pro level DSP is required for this complexity of subwoofer crossover, as I mentioned earler. I don't see any other immediate options that would let you have the quality of bass reproduction that you apparently desire. Please describe the current method used to actively crossover the speakers to the subs. Or are you using the mains full range? What's going on?

-Chris

 

[mulester7]

are you using the mains full range?-Chris

.....yes, Chris, the mains are receiving a full-range signal....but they are two-way....I am soon to parallel two like-mains on each B-12 cabinet, to bring a little more low end to the mains.....

 

[WmAx]

.....yes, Chris, the mains are receiving a full-range signal....but they are two-way....I am soon to parallel two like-mains on each B-12 cabinet, to bring a little more low end to the mains.....

Mulester: please explain what you mean by: "I am soon to parallel two like-mains on each B-12 cabinet".

You need to stop using the mains full range. This is causing loss of audio fidelity. You must crossover the mains to the subwoofers using a phase coherant network in order to have optimal integration. Are you using a reciever or a seperate amp/preamp setup for the mains? I ask this because it will be easy to insert the proper hardware into a preamp/amp component set-up. More difficult in most applications where an integrated/reciever is used. If the reciever has built in active crossover system, this should be tried, but in many cases the options available will not be sufficient in such a system, in order to achieve optimal sound quality.

-Chris

 

[mulester7]

Mulester: please explain what you mean by: "I am soon to parallel two like-mains on each B-12 cabinet".

You need to stop using the mains full range. This is causing loss of audio fidelity. You must crossover the mains to the subwoofers using a phase coherant network in order to have optimal integration. Are you using a reciever or a seperate amp/preamp setup for the mains?-Chris

.....Chris, I now have one main on each B12....I have another pair of mains coming just like the ones I have....I am going to have twoooo, ha, mains paralleled on each B12....you are referencing 3-way mains when you say it is not good to let the mains eat all the way to the floor concerning full-range against subs, trust me....I have a McIntosh C-26 pre-amp and K2's everywhere, Chris....bass management, as with surround recievers, doesn't apply to 2-ways nearly as much....it will be there, I already hear it in my head....and, haha, I've already tried two mains paralleled, sitting on one B12, listening to the left channel....what I need more than anything, is all the components here to play with....where's a bank I can rob?.......

 

[mulester7]

.....guys, let's look at real-life here just a bit....my 4.2 system accents the front mains....the rears make the mains suddenly 10 feet wider concerning the sound-stage....isn't this what happens with you surround receiver guys?....when you are watching a DVD, aren't you like looking through a plate glass window into the scene?....why do I want sounds coming from behind me that do anything but widen the front?....why is it bad for the low end to be directional to the mains?.....

 

[WmAx]

.....Chris, I now have one main on each B12....I have another pair of mains coming just like the ones I have....I am going to have twoooo, ha, mains paralleled on each B12....you are referencing 3-way mains when you say it is not good to let the mains eat all the way to the floor concerning full-range against subs, trust me....I have a McIntosh C-26 pre-amp and K2's everywhere, Chris....bass management, as with surround recievers, doesn't apply to 2-ways nearly as much....it will be there, I already hear it in my head....and, haha, I've already tried two mains paralleled, sitting on one B12, listening to the left channel....what I need more than anything, is all the components here to play with....where's a bank I can rob?.......

You can not randomly run two drivers across the same band out of significant relative phase rotation, and expect optimum integration. That's exactly what you are doing when you run the main speakers full range along with the subwoofer. As the response rolls off from the main, the phase rotates, misaligning with the subwoofer, and the same occurs at the upper range crossover point of the subwoofer where it crosses over. You must use a properly crossed over network if you want optimal results, and to ensure the flattest frequency response. So far as directional base, I already stated what made bass seem to be directional in former posts. By creating an inherantly directional subwoofer to simply add-on the system is not a good idea, if the objective is to have a properly operating system.

Also, running two full ranges side by side as you are planning will reduce dispersion linearity, as you are now reducing the horizontal polar response[dispersion] linearity further by adding a significantly larger driver radiation surface in the horiztonal plane. Also, the speakers are designed with a shelf function called a baffle step correction[relative change of radiation space vs. frequency wavelength as the cabinet face becomes small in relation to such frequencies]. This accounts for the speaker baffle width. By doubling the effective width by placing two speakers next to each other, you will cause an alteration of the midrange frequency response.

-Chris

 

[mulester7]

You can not randomly run two drivers across the same band out of significant relative phase rotation, and expect optimum integration. That's exactly what you are doing when you run the main speakers full range along with the subwoofer. As the response rolls off from the main, the phase rotates, misaligning with the subwoofer, and the same occurs at the upper range crossover point of the subwoofer where it crosses over. You must use a properly crossed over network if you want optimal results, and to ensure the flattest frequency response. So far as directional base, I already stated what made bass seem to be directional in former posts. By creating an inherantly directional subwoofer to simply add-on the system is not a good idea, if the objective is to have a properly operating system.

Also, running two full ranges side by side as you are planning will reduce dispersion linearity, as you are now reducing the horizontal polar response[dispersion] linearity further by adding a significantly larger driver radiation surface in the horiztonal plane. Also, the speakers are designed with a shelf function called a baffle step correction[relative change of radiation space vs. frequency wavelength as the cabinet face becomes small in relation to such frequencies]. This accounts for the speaker baffle width. By doubling the effective width by placing two speakers next to each other, you will cause an alteration of the midrange frequency response.-Chris

.....Chris, you go deep with theory....I get in the thick middle of it using my ears, and fight for what I want....it's different with a 2-way mains regiment, I promise....there ain't a whole lot of phase on the lower end to step on with subs, especially off the floor sitting on the B4's, but I will not lose the dispersion from almost five feet off the floor with the mains....two of my mains sitting side-by-side on one B12 sound great projecting one channel....once again, two sound like three....the area of powerful imaging is staggering....I need no center, just balance, but may use a pair of speakers just like the rears for centers one day, as they are the perfect full-range to augment the mids against my mains' resolved highs....the lower end of paralleling two of my mains sitting on a B12 is stouter also, with three ohm watts hitting the paralleled six ohm speakers....you know me, Chris, haha, I will report as I receive, incorporate, and tweak....you're posting as if I have death-dealing problems facing me with my sound system, Chris....I promise, I don't....just obstacles to overcome applying experience.....

 

[WmAx]

If you are happy with the [inferior as compared to what could be obtained with my recommendations] performance that will be achieved by doing as you plan, then of course, that's all that counts.

-Chris

.....Chris, you go deep with theory....I get in the thick middle of it using my ears, and fight for what I want....it's different with a 2-way mains regiment, I promise....there ain't a whole lot of phase on the lower end to step on with subs, especially off the floor sitting on the B4's, but I will not lose the dispersion from almost five feet off the floor with the mains....two of my mains sitting side-by-side on one B12 sound great projecting one channel....once again, paralleled, two sound like three....the imaging is staggering....I need no center, just balance....the lower end is stouter also, with three ohm watts hitting the paralleled six ohm speakers....you know me, Chris, haha, I will report as I receive, incorporate, and tweak....you're posting as if I have death-dealing problems, Chris....I promise, I don't....just obstacles to overcome......

 

[mkossler]

.....edit....many thanks to Brian and McKesslor for my now having an avatar.....

Hmm - McKesslor...well, you got close anyway, Mulie

Maybe I should change my nick to McKossler, seeing as I am Irish-German. It's a great combination - we like to drink beer, and we like to fight about it

Back on topic, I think WmAx makes some points that are hard to argue with, pal. I'm sure you have the resources to re-configure if you don't llike what you end up with, but a single investment to get what you (and your ears) want would seem to be the fastest path to your audio nirvana.

Cheers!

Matty K

 

[Buckeyefan 1]

Mule,

Are you using a set of Rane PE-17 5 band parametric eq's with your B12-Plus/4's?

Are these sub's "just too low" for music, regardless of equalization?

Finally, do your front mains go any lower than 150Hz at +3 dB? Or, I should ask, 50Hz at 0 dB?

 

[mulester7]

Hmm - McKesslor...well, you got close anyway, Mulie

I think WmAx makes some points that are hard to argue with, pal. I'm sure you have the resources to re-configure if you don't llike what you end up with, but a single investment to get what you (and your ears) want would seem to be the fastest path to your audio nirvana.

Cheers!

Matty K

.....Matty McKossler, a thousand pardons, and I wish you posted more often....after dumping the emails and not seeing a post by you anywhere close, I took a stab....many thanks for bringing the avatar home for me.....

.....and I believe the most direct path for solving my nirvana would be smaller sealed enclosures, but, I ain't wantin' to build anything at this time....will either order a Cadence X-sub, or go to a car shop and see what boxes and drivers they got....but with a sealed box, here comes the need for power, and a Behringer 2496 or a Paradigm X-20 at least, if not an X-30....with the Cadence sub, the full-range signal to the sub would already be bottom-cut at 50, 80, or 120, coming from the satellite outputs of the Paradigm X-30 I already have, and the Cadence can cut the top.....Matty, thanks for recognizing my audio nirvana....do you feel my intense pain in this crisis?, haha.......

 

[mulester7]

Mule,

Are you using a set of Rane PE-17 5 band parametric eq's with your B12-Plus/4's?

Are these sub's "just too low" for music, regardless of equalization?

Finally, do your front mains go any lower than 150Hz at +3 dB? Or, I should ask, 50Hz at 0 dB?

.....Buck, I am using a Paradigm X-30 for the B4's....I generally have the top cut from 50-75.....

.....the B4's have a different sound from other subs I've heard....there are not elements down-firing into a plate, nor elements front-firing direct....oscillations are sorta' sawed out the front window/door....two elements are on each side with one about six inches behind the outside one with a sealed air space between them....one side of two is wired in two parallel circuits....the other side of two is wired in out-of-phase series, and is out-of-phase with the paralleled side....standing in front of the box, all the drivers are moving the same direction, left to right, or right to left....clear as mud?....oscillations are produced in the inner cavity and pushed/projected/sawed out the window/door of the side opposite, from the side that has the small SVS logo plate....yes, the side with the small name-plate goes toward the wall behind the sub....

.....most people would love what the B4 produces and be done with it....most people who prefer down-firing, would listen to larger down-firing subs and be done with it....I gotta' have more punch from front-firing small cannons in the middle of the mix, now there it is....all the talk about phases out-of-whack and it won't work are not getting a great deal of attention from me....I know it will work just fine....the only things to be careful of is volumes and mud from phase overlap.....

....my front mains are two-way floor-standers, Buck, with only one soft-dome button tweeter and one 8 inch woofer....the woofer is geared more toward the low-mids up....wouldn't change that for love or money....just needs some help lower down, and paralleling two will help the low end some....if there is a need for help past that, the help is out there....I will find it....where's my flashlight?.......

 

[Tomorrow]

Mulie-with-new-avatar,

You seem to have rejected out-of-hand any experimentation/discussion of larger mains with more significant passive sub support. Why is that? It seems you are perhaps causing yourself a problem without need. But maybe you've tried and found wanting most full-range floor-standers. Or maybe I've forgotten some piece of this wandering thread.

But for me, this thread has activated a new question. Does a sub with a larger enclosure not only make more depth available (than its smaller brethren), but also loosen its blast measurably(the cannon of which you speak and seek)? I am caused to think about the pros & cons of the SVS PB12-ISD versus the same sub in V configuration. You can plug up that big ol' V-box, but is it still as tight as it's smaller cousin? Dunno.

 

[mulester7]

But for me, this thread has activated a new question. Does a sub with a larger enclosure not only make more depth available (than its smaller brethren), but also loosen its blast measurably(the cannon of which you speak and seek)? I am caused to think about the pros & cons of the SVS PB12-ISD versus the same sub in V configuration. You can plug up that big ol' V-box, but is it still as tight as it's smaller cousin? Dunno.

.....very good question, RJBudz....am up with coffee in hand, still sweatin' from a HOT bath....gits the blood going quick....I hit the hay early last night to do something this morning.....

....yes, RJBudz, SVS offers an entry-level ISD 12 inch subwoofer element in a box for music, THE PB 12 ISD, and a LARGER box for Home Theater, the PB 12 ISD/V....plugging the smaller box for music would be unthinkable for me, but one plug in the box intended for HT could be nice....but you would have to jack the volume a little, as the sub's tuning just hit Earth-dirt, and buried the nose-cone a little....everything moved down frequency range-wise with the port plug or plugs, as the internal pressure is not being released as readily flowable through the ports....correct, the sub's tuning just went unnatural.....but like I said, Home Theater, down to 16, or 12, if the unplugged port or ports didn't whistle, maybe......

 

[WmAx]

But for me, this thread has activated a new question. Does a sub with a larger enclosure not only make more depth available (than its smaller brethren), but also loosen its blast measurably(the cannon of which you speak and seek)? I am caused to think about the pros & cons of the SVS PB12-ISD versus the same sub in V configuration. You can plug up that big ol' V-box, but is it still as tight as it's smaller cousin? Dunno.

The problem that may arise with a massive size subwoofer cabinet responding to higher bass frequencies is centered around the enclosure's signficant parallel dimensions. The system will resonate, if a frequency approaching and or meeting 1/2 the wavelength in air, is reproduced within that cavity, and if that cavity does not impliment substantial measures to prevent this effect. The amplitude gain achieved in such a cavity is substantial. You have to account for the crossover slope, because if the center freqency of the cavity is 180Hz[keep in mind that affected frequencies extend in both directions from this center frequency, it's not just one single frequency that is affected], for example, then a crossover rate of 80Hz at 12dB/octave would not be sufficient. A 24db/octave rate would probably be cutting it close, and may still result in some audible resonance -- but it needs to be analyzed on a case by case basis.

-Chris

 

[MacManNM]

Mule,
I think what you really need is a several band active crossover. You can set it to send everything from 30Hz down to the B-4's, then use a channel to send 30-70Hz to a pair of suspension subs (a good 12" driver in an over damped enclosure forward firing of course) and finally 70 Hz and up to your mains. Using separate amps for each, and a parametric Eq on the top to clean up any resonance. This should fill in the gap you have in that lower mid bass region. The parametric Eq will allow you to compensate for the roll off of the 12” in the sealed enclosure. By setting the x over frequencies correctly you should be able to minimize any phase issues in your room, and should sound quite nice.

 

[malvado78]

My Suggestion

Mule...

If you are looking for the small cannon effect there is one option not yet explored....

Figure out a way to wire a couple of cannon so they go off with the bass. There is precedence for this... In the 1812 Overture. Many time they have used real cannons for the cannon part of that piece instead of drums.

You may not want make them front firing as you said earlier though for it may get fairly tiresome of needing a shower whenever using your HT from the power residue you are covered with.

These may work for you.

Front Firing Cannons

Although I'm not sure how the crossover will work....

 

[mulester7]

Mule...

If you are looking for the small cannon effect there is one option not yet explored....

Figure out a way to wire a couple of cannon so they go off with the bass. There is precedence for this... In the 1812 Overture. Many time they have used real cannons for the cannon part of that piece instead of drums.

You may not want make them front firing as you said earlier though for it may get fairly tiresome of needing a shower whenever using your HT from the power residue you are covered with.

These may work for you.

Front Firing Cannons

Although I'm not sure how the crossover will work....

.....Malvado, you may have just found my answer.....you think they would take plastic for the cannons?....

.....Malvado, I'm coming to you live and in person from the library again, for real....my modem went haywire yesterday around noon when the power went off....now I have an orange light in the middle of two greens, when three greens is normal....I'll be back eventually.....thanks for the response......