Are 8's the new 12's?

[IamDeMan 5,000+ posts]

The easiest isobaric configuration to implement is best described as a clamshell. Two speakers are mounted face to face, in this case on the lower subwoofer baffle. A picture showing the clamshell isobaric configuration in a sealed box is on the right. The outer driver is wired out of phase to produce the correct mechanical movement. This has the desirable side effect of helping to cancel driver non-linearities.

http://www-personal.engin.umich.edu/~jglettle/section/pyramids/subs.html

From what I think I know, minimal output increase over a single driver but space requirements are half of a single drivers requirements.

 

[helotaxi 5,000+ posts]

There's actually no output increase over a single driver you're only moving the same amount of air. The effects are a decrease in Vas and an increase in Mms (keeping Fs the same) but it takes 2x the amount of power to get the same output. The tradeoff for the decrease in efficiency is the decrease in Vas allowing the use of a smaller box. The benefit is pretty much lost on an 8 which is already wanting a box so small that porting it requires a port displacing as much air as the enclosure volume.

Isobaric setups became popular back when the typical 12" sub had a HUGE Vas with a low Fs (really efficient but not much on the power handling) leaving them wanting a massive enclosure. To make the enclosure practical for a car you would use 2 drivers in an isobaric configuration allowing for single sub output and response in a box that was half the size of what the single driver wanted. The drivers were really efficient, so the loss in efficiency wasn't that much of an issue and a fair sacrifice to get a sub into the car that otherwise wouldn't have the room.

Modern subs generally have a tighter suspension (lower Vas) and a heavy moving assembly and are effectively an isobaric pair in one driver. There's a reason that you need a ton of power to get a lot of the newer subs really moving! Doubling up something like that into an iso-pair just doesn't make a lot of sense an really is a waste from a monetary standpoint.

 

[CBFryman2 5,000+ posts]

Tang Bands **** hard, they are quiet and don't sound that great. I havn't tested the Assassins as they were supposed to send us one to test but never did. Honestly, I havn't used another 8 that performs like the RE8 does for the price the RE8 used to go for. FYI, I did 140's with a single RE8, still do, my highest is a 146 so far. It didnt take THAT many of them to do it.

Mid 140's in a completely daily system. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

Assasins kick ***. Better than RE's IMO.

 

[80INCHES 5,000+ posts]

There's actually no output increase over a single driver you're only moving the same amount of air. The effects are a decrease in Vas and an increase in Mms (keeping Fs the same) but it takes 2x the amount of power to get the same output. The tradeoff for the decrease in efficiency is the decrease in Vas allowing the use of a smaller box. The benefit is pretty much lost on an 8 which is already wanting a box so small that porting it requires a port displacing as much air as the enclosure volume.
Isobaric setups became popular back when the typical 12" sub had a HUGE Vas with a low Fs (really efficient but not much on the power handling) leaving them wanting a massive enclosure. To make the enclosure practical for a car you would use 2 drivers in an isobaric configuration allowing for single sub output and response in a box that was half the size of what the single driver wanted. The drivers were really efficient, so the loss in efficiency wasn't that much of an issue and a fair sacrifice to get a sub into the car that otherwise wouldn't have the room.

Modern subs generally have a tighter suspension (lower Vas) and a heavy moving assembly and are effectively an isobaric pair in one driver. There's a reason that you need a ton of power to get a lot of the newer subs really moving! Doubling up something like that into an iso-pair just doesn't make a lot of sense an really is a waste from a monetary standpoint.

//content.invisioncic.com/y282845/emoticons/thumbsup.gif.3287b36ca96645a13a43aff531f37f02.gif//content.invisioncic.com/y282845/emoticons/2thumbs.gif.fdc3ba010dbb42b61704534b46d02fe4.gif//content.invisioncic.com/y282845/emoticons/word.gif.64b12e39f936af3b4fff38a1c0bd0244.gif//content.invisioncic.com/y282845/emoticons/iagree.gif.15d6c075ee8d3913ba26866d06993068.gif

couldnt have said it better myself

80

that reminds me of the old b52 subs made for cars...oor how bout the redline g&s design subs....oh yes those bring back memories

 

[ibanender 10+ year member]

Never said they did (for the eleventieth billion time). I was comparing like model subs. For someone who knows t/s perameters, you sure are acting dense about such a simple concept.
The point wasn't specs are the most important, the point was you talk about doing things scientifically, until you decide your experience trumps it.

Yet another lame person attack. *yawn* Yes, like I said before, unless Ive added weights to subwoofer spiders and tested the affect on Fs (and F3), I must really be one shitty *** car audio dude. //content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif

If Ive learned, why are YOU continuing? Aparently Im suppose to bow my head low and back out of your presence?

No, you only seem to ignore posts comments and sources that contradict you.

You were comparing like model subs, and you've admitted and given an example of your own, that were in fact different subs all together. For being "like model subs" they are awefully different.

Experience IS science. You don't find the outcome of an experiment without doing the experiment. Theories are just that. They aren't fact till the theory has been tested and a conclusion is drawn. You can't t/s param and mock up all you want, but what it does in the real world is what counts.

What source contradicts me? Others have backed up my points because THEY GET IT. You are completely missing the entire point of everything I've said. I don't know any other way to explain it, it's been put in terms a 13 year old can understand. If you can't walk away from this thread without understanding (when I think you say you do now, but apparently not really), then you just keep on doing what you do and keep smiling. Ignorance is bliss.

 

[ibanender 10+ year member]

Yeah, the message got lost in the battle LOL.
I'm sorta thinking about running an 8 setup. I think I need to make you my best-friend 80 so that I can ask you dozens of questions about box building. I'm really getting interested in making new boxes, trying out some stuff and I just finished a room downstairs (kinda a basement) to start building boxes.

I have a seriously crappy box right now and I want to try out some new designs.

I'm running 10's right now and I want to try out my RE 8's that I got for a really cheap price when they were running that sale a year or so ago.

I like the RE8. They sound decent but are usually a bit peaky around the 45 hz area. They do OK for SPL, but there are better for around $100 or less. The only real flaw with them is that they can and will bottom out if you aren't careful. Once they bottom out, they are done for.

 

[ibanender 10+ year member]

//content.invisioncic.com/y282845/emoticons/thumbsup.gif.3287b36ca96645a13a43aff531f37f02.gif//content.invisioncic.com/y282845/emoticons/2thumbs.gif.fdc3ba010dbb42b61704534b46d02fe4.gif//content.invisioncic.com/y282845/emoticons/word.gif.64b12e39f936af3b4fff38a1c0bd0244.gif//content.invisioncic.com/y282845/emoticons/iagree.gif.15d6c075ee8d3913ba26866d06993068.gifcouldnt have said it better myself

80

that reminds me of the old b52 subs made for cars...oor how bout the redline g&s design subs....oh yes those bring back memories

Advent made a box like that too, they pushed it for SUV's and vans pretty hard.

 

[audioholic 5,000+ posts]

You were comparing like model subs, and you've admitted and given an example of your own, that were in fact different subs all together. For being "like model subs" they are awefully different.
Experience IS science. You don't find the outcome of an experiment without doing the experiment. Theories are just that. They aren't fact till the theory has been tested and a conclusion is drawn. You can't t/s param and mock up all you want, but what it does in the real world is what counts.

What source contradicts me? Others have backed up my points because THEY GET IT. You are completely missing the entire point of everything I've said. I don't know any other way to explain it, it's been put in terms a 13 year old can understand. If you can't walk away from this thread without understanding (when I think you say you do now, but apparently not really), then you just keep on doing what you do and keep smiling. Ignorance is bliss.

//content.invisioncic.com/y282845/emoticons/eyebrow.gif.fe2c18d8720fe8c7eaed347b21ea05a5.gif

You just never give up, do you? You are like a dog that just wont quit humping my leg. Even after Ive resigned myself to letting you finish humping, you continue on and on.

Ive told Pl8er I wont continue this, and I wont. Maybe you would be big enough to do the same? If you want to pm me, feel free. Otherwise, get off my jock.

Have a nice day.