Sub woofer question

audi-a6

audi-a6

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Probs a dumb question, but dont ask, dont know........

I want to upgrade my sub to a vibe space 15" dvc 2ohm rms 1200w but i dont want to really change my amps, I have 2 x vibe mono box 600w rms @ 2ohm amps, can i run one amp to each voice coil as each coil is 2ohm ? amps are identical and i can keep settings exact same too.
 
Yes of course you can - you'd need to ensure you feed them with the same signal, not left to one and right to the other but left & right to both
 
and would the 1200w rms still apply or would it be reduced, i imagine it is 600 per coil?
 
you cannot simply put an amplifier onto each coil of the speaker
the gains must be matched or the speaker will try and tear itself into two pieces and when this happens it could damage one or both amplifiers

the best way to do this is by using a test tone and a multimeter and reading the voltage which is being sent from the outputs of the amplifier to the woofer
 
Yeah i thought that, iv decided any way to change amps, so i can just run one amp instead of 2. Its easier lol i can get a nice 1500w rms @ 2ohm vibe amp at a fairly good price, just need to decide now as to wether i go for the vibe space 15 or dual blackair 15's any one know which would produce the deepest bass?
 
why vibe ???
there are lots of other makes which are far more capable and have better reliability
 
dunno, its one of those things, i have used vibe for years and trust their quality and sound......

what else would you suggest? im trying to achieve hi db but at the same time i want the car to shake with bass, iv managed to tear my self away from vibe speakers and gone over to infinity, 2 sets of 6.5" components in all doors and a pair of 6x9s on the shelf all amped up so volume wise i have achieved my acquired level i just really want lots of bass now but costing lots of money, again comes to vibe, good deep loud bass and good bang for buck
 
for that kind of sound i would be looking at something from ground zero , fi , spl dynamics
bit more money , but louder and considerably better built
 
i like the look of the ground zero's,,,,,,,,,,,,,,,,, i feel my credit card crying to come out!!!
 
the 15" looks good on the other hand, they dont handle alot of power though do they
 
If by 15" your talking about vibe. Then vibe are ****.
Google or youtube search sundown audio sa-8. You can get them in 10 or 12" flavor. But you will be surprised,

Like i said will blow any vibe 12 or 15 out the water. And many other makes for that matter. Don't let the 8" part fool you
 
saying that, as there only 8", i could build an enclosure that could house 4 of them, as they only require 0.3 cubic foot
 
audi-a6 said:
the 15" looks good on the other hand, they dont handle alot of power though do they
Click to expand...

audi-a6 said:
no, i ment the sundown 15"
Click to expand...

thats becasue they dont lie about there rms and max power like vibe,

i work at halfords and we are vibes seller, but i dont rate them

i had some slicks and powered them at there rms power and they didnt last long.
 
best i could find

8"

http://www.youtube.com/watch?v=FexmSSeGt3s

12
1 Sundown audio Sa 12 on 1200 watts - YouTube


i had a sa8v1 and the v2 is even better, seriously dont let an 8" fool you.

2 of these in a 3cuft box with a 4"d x 5"l port will shake your car apart.
any they do hit low for 8's



forgot to say i had mine running 900wrms all day long, i still have the amp actaully, but stuck a nice big hole in the sub, its in the loft keep meaning to get it reconed so just have a jbl 1000 in atm and to be fair its diffrent but enjoy no so much bass now, maybe im getting old
 
your not one of those that belive every thing they hear and read are you.?

i had mine in a 1.5 cuft box running 900wrms, lasted well over a year before i damaged it, and not by the voice coil.

just google them they hit lows, there a suberb sub, im not going to say any more then that, if you wanna stay with vibe then be my guest, but stick one or two sundowns in and your never use vibe again. or a 15" sub.

thing witrh a 15" sub is its VERY sloppy, your sub will be missing ALOT of notes, and itll be like night and day between the two.
 
na, just trying to understand a new brand lol......... so surley, am i not better off playing it save and go for the 12", not to sloppy and can hit most required notes, also, what kind of power can these handle as was just looking on you tube and they all running different power? eg a guy running one 15" (800w rms) on a 1200 amp?

Sorry for all the questions, but i dont want to go buy new subs (no matter what the brand) and just blow them or have them tuned wrong..... I suppose thats why i have always stuck with vibe, as i know there limits
 
thing is with vibe, you have to stick with the rms and hope it can handle it,

you go with proper named brands like my self with a jbl 1000watt sub, its rms is only 300watts but will handle 1000w all day long, and is currently at 900wrms on my amp.

now you have to look at cone surface area, but you also have to consider excursion

for example and numbers are to simplify calculation, and may not be spot on

take a 15" sub that has a surface area of 100cm3 and a 8" sub that has 60cm3 cone area

if the 15 excursion is 1 inch it moves 100cu cm3 of air, and the 8" has 2", for example the sa8 has 2" excursio, itll move 120cu cm3 of air

so the 8" can move more air then the 15" theoretically, thats how its so loud for such a small speaker, its not only how big, but how much air it can move, and it has a large motor to push and pull the air.
 
Im defo hooked on to them, just trying to decide on size, I know your saying 8's but i like i deep hard punch, which i think i will only get from a 12 or 15, im going to run 2 any way so would you say go for 2 ohm dvc or 4 ohm dvc? Iv got a amp which i could run them off for now which is something like 940 @ 1ohm 1460 @ 2ohm so that should be plenty of power?
 
yer the 8 hits as hard as the 12,

also your amp dosnt put out higher rms with a higher ohm, did you get them mixed up

just look at this

2 Sundown Audio SA-8's on a SAZ1500D Roof Flex in HD - YouTube

single Sundown SA8v2 153.3 dB - YouTube

Sundown Audio SA-8 V2 D2 - YouTube

4 SA-8 V2 Stupid lows - YouTube



if you can find me any other 8" sub or 12 or 15 that hits like that ill eat my own pants

if you read and understand my comment about cone area and rxcursion you would understand how a 8" sub can hit as hard and low as a 15"
 
ok let get a bit more technical,

its all math.... just times the X-max by the area... that will tell you which pushes the most air.

to figure this out, pie x R^ x X-max


sa-8

3.149 x 7.5 = 23.615

then times by xmax which is 16.5mm
so 23.615 x 16.5 = 389.68875

sa-12


3.149 x 11.5 = 36.21
then times by xmax which is 19mm

so 36.21 x 19= 688.05

compare that to a vibe 15"

3.149 x 14.5 = 45.66
then times by xmax which is 14mm
45.66 x 14 = 639.44


so as you can see the vibe comftable beats the 8 but is beaten by a 12"

even still the 8" is close to 400cumm3 of air movement,

so 12" would provide more low then the 15"

what sub do you have now?
 
its a little more complicated than simply xmax as well
there are a whole heap of thielle small parameters which affect all woofers , but reading a manual or specs doesnt tell you how there going to sound hes not entering an spl competition he wants to listen to music loudly

and the best way to do that is to use a simple sealed enclosure , not ported
 
audi upgrades
What are you talking about?

Theile small parameters determine how the speaker works. What i worked out is how much air the sub can push.
By calculating the area of the cone by how far the cone travels.

Im just doing that to compare the vibe to the sundown one.

And a 12 sa will push more aire then a 15 vibe. Meaning the sa will be louder then a vibe simple as. Don't complicate things further by talking about theile small parameters
 
And yea a sealed is best for daily listening but ported is beat to achive the loudest bass or spl
ok if i replace the word push with compress then would that mke you happier? For exaple the sa8 has a massive motor cable of pushing or compressing the enclosed air with alot of force. Thts how a 8" sub from sundown sounds so loud.

Dont underestimate what the sundown audio subs can achive
 
Last edited:
i am running 2 x vibe slick 15's, sealed large enclosure and 2 x vibe 450rms amps......
 
boost-addict said:
yer the 8 hits as hard as the 12,

also your amp dosnt put out higher rms with a higher ohm, did you get them mixed up

just look at this

2 Sundown Audio SA-8's on a SAZ1500D Roof Flex in HD - YouTube

single Sundown SA8v2 153.3 dB - YouTube

Sundown Audio SA-8 V2 D2 - YouTube

4 SA-8 V2 Stupid lows - YouTube



if you can find me any other 8" sub or 12 or 15 that hits like that ill eat my own pants

if you read and understand my comment about cone area and rxcursion you would understand how a 8" sub can hit as hard and low as a 15"
Click to expand...

yeah it does, 2ohm is higher than 1 ohm, i know usually it is not the case see here http://www.vibeaudio.co.uk/manuals/old/blackbox_bass4_blackboxbass5.pdf mine is the "bass 5"
 
thielle small parameters give an indication of how the woofer is going to respond to a given frequncy and box size
pretty important when your talking about listening to a woofer playing music

but off course absoloubtedly no consideration when used in an spl system ...

yes a ported enclosure is louder than a sealed enclosure given the same power but with a ported enclosure you also have
a portion of the sound which you cannot play as the woofer will unload and **** itself below the tuning frequency and try and turn itself inside out (this is where you generally try and add a subsonic filter to try and stop the really low stuff getting to your woofer )
this isnt a consideration when you use a sealed enclosure as the air pressure helps stabilise the cone suspension so a sealed enclsoure will play all the frequency range and a ported enclosure wont

its upto the thread originator what he wants in his car but give him all the facts not just how to get louder and make it sound worse
 
thank for info, iv always preferred sealed enclosures any way, as you say, they help to hit most notes.......... this is why i have also been hooked 15's as they can hit the lows that i want, dont get me wrong, im not doubting the sundown sa-8'S i just think that 8's will look lost in my car as also i like the boot stuff to look good, if i could afford it i would have 4 x sa-8's just so it looks good lol but a bit over the top.... so at the moment given that the sa-15's dont seem to get a lot of wows im inclined to go with the Orion hcca 15 or the t-rex from Db audio.......... "boost-addict" i am grateful for your advice on the sun downs as they have lead to me to a whole different world of speakers........

"dualmono" so for sealed enclosure, is it better to go bigger or stick to manufactures limit. Although i want a high db level and want to be able to hit ultra low frequencies. the rest of my set up can handle the db's.

Has there ever been talk of putting different sub sizes together? IE a 15 sealed to handle the ultra low and a 10 or 12 ported to handle volume and a more frequency range?
 
usually a speaker which has been devolped to work in a sealed enclosure has a reccomended range for which to get the optimum performance from it ..... you stick in that range but tend towards the upper limit on box volume
the other option you have to hit the very very lows without killing anything is to add another driver
this could be as simple as using a pair of woofers in a common enclosure or as complex as using a well designed and built
isobaric enclosure which uses 2 woofers in the same space as the maximum for one driver but one driver fires into the back of the other ... this gives a very very good extended frequency response right down to the lowest of lows but doesnt give an overall increase in actual spl level

i wouldnt advise putting differant sized drivers in to run the subbass as they will then suffer phasing problems and issues while trying to get the pair to work together ...even if one was left unpowered it will still cause issues
 
ahh, okay, well im still deciding on what sub to get, as i said earler im tempted with an orion hcca 15.... if i had one of them in a proper vented box, would that be enough?
 
only you know how loud you want things
the only thing i will say is if your serious about music stick with a sealed enclosure

if you just want to listen loud an orion 15 in a large ported box will definately be loud but itll also sound like ****
 
cool, well its sorted, got a 15" orion hcca, with a 3 cu ft ported box with port plug being custom made, so i can have the best of both worlds, just amp to sort now..... hifonics? any good?
 
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