Adire Shivas

I'm looking to buy 2 adire shivas for my car. They were recommended to me by a friend that said a lot of competitors use them in db drags. Everything i have been reading about the subs are related to home theater however. If i do go ahead and buy these, do i need a ported box for them, and if so, what should it be tuned to? I'm probably going to by a Sony class-d amp to power both for now, but i will buy another amp when i have enough money. if anyone can help, please reply to this post and thanks. The link to the amp and subs are below.

amp - http://www.sounddomain.com/sku/SONXM3001SXD
subs - http://www.adireaudio.com/cd/shiva.htm
 
Look here...

In addition to contacting Dan @ Adire, for some 'user' feedback, go here: http://www.soundillusions.net

this board saw the adire products get popular by users doing well in comps (one his 150.xx outlaw db's with only 500 w RMS)

as far as porting vs. sealed- the AdireAudio.com website has a LOT of info on how to configure their drivers for specific use.

If you're going to compete in dbdrag, et al, you'll likely end up porting the sub(s) just below you car's transfer f(x) freq. (ie: cabin gain point) b/c it'll reinforce the program material at that point.

DigitalDesigns has done a lot of work on porting VERY big boxes at pretty high freqs (40 - 55hz)- it produces a lot of sound (albeit at 'one note')

do some searches there on "cabin gain" and "transfer function" and read- most of those q's have been asked and answered. Also, search for those users who run Shivas and tempests there are at least 1/2 doz. who'll be on there every day.

Personally- try to figure a box that has 2 ports- so that one of 'em would be plugged for daily use (with a proper/low porting freq) and when their both opened/unplugged, you're up to your specific "competition" frequency. If not, you'll likely tire of the monotone bass.

Adire products put out great SQ, don't waste it just for the sake of DBs. With port pluggin/unplugging, you can have your cake and eat it too.
 
okay ive been reading about the shivas, and people say that you can put more watts through one without having it bottom out if you put it in a sealed enclosure. how does this work? also, i definetely WILL NOT COMPETE with my sound system. i want it for personal enjoyment only. therefore, i need accurate deep bass. should i still go with the ported box?
 
Just a general note, but most bass drivers will have higher power handling when placed in a sealed enclosure.

Personally, I would recommend the use of a sealed enclosure, space permitting. The bass will be tighter, and you will likely have usable output below 20hz, especially when factoring in cabin gain and the fact that you are using dual drivers. As mentioned earlier, a ported enclosure may result in "one note" bass, which can get particularly irritating.
 
Thunderbird said:
okay ive been reading about the shivas, and people say that you can put more watts through one without having it bottom out if you put it in a sealed enclosure.

yes and no. sealed boxs can increase the powerhandling of a sub- mechanically- ie: they can keep it from bottoming out at the lower end of the spectrum- but they cannot keep the VoiceCoil from frying if too many electrons are pass through it. There's a big difference.

Sealed box design, allows for smaller boxes and usually a very smooth response graph; esp in cars. You see, as the 'reference' plot 'drops', the car's cabin gain makes up the difference. Low ported boxes can produce an overabundance of very low bass in cars.

Thunderbird said:

how does this work?
read this page: http://216.150.71.139/audioinnovation/theories.html for a buncha good info.



Thunderbird said:

also, i definetely WILL NOT COMPETE with my sound system. i want it for personal enjoyment only. therefore, i need accurate deep bass. should i still go with the ported box?

go sealed- in car, you jaw will drop at the lowend power and accuracy.

(and you'll have more trunk space left over)
 
Re: amp?

Thunderbird said:
also, anyone have any idea what volume the sealed box should be?

see the adire site- they've done a lot of work on the subject- they're the ones to ask (or 'read' their PDF files, first)


Thunderbird said:
how about my amp? do you think it will be adequate to power both subs in a sealed enclosure until i get another one?

I'm not crazy of Sony car amps (personal opinion of course, but i prefer less flash and more go- like Zapco or PPI PC models)... but $0.50/watt is hard to beat.

but based on the numbers (600 x 1 at 2 ohms) that'd give each 300 watts- plenty for inside your car for casual listening.
 
Well I always say go big or go home so if you have the dough go for Rockford-Fosgate amps. Pop a RF Power 1000.1 on each Tempest and watch the SPLs climb. Some more informed car audio enthusiasts will probably be able to recommend something else, but as fas as I know RF is a good way to go.

PS..Never mind me...if this is useless info then I will go crawl back into my hole...I blame school...yes...thats it...

[Edited by baby_huey0 on 11-18-2001 at 07:41 PM]
 
Re: Deepness?

Thunderbird said:
Talked to a friend today and he was doubtful about the shivas having "deep bass or pressure", but he said that they have SPL qualities, which are just 'loud' subs. are the shivas SPL subs or do they really hit you with the bass? if anyone has aol, my sn is qwerty2002, IM me sometime! thanks

If they put out good SPL numbers, they put create pressure. I don't know of any difference between 'pressure' and 'spl' - in how you describe him using them... I thought they were the same, or rather, SPL is a measure of sound pressure. The 'depth' has to do with freq. response of the output- and the shivas are definitely not lacking there. You friend should download the datafiles on the drivers from AdireAudio and model the curves himself. (or maybe he's trying to justify the $$$ he spent on his subs ;-) )

Technically, if a sub can do the following it can be both loud and clean:

1) flat freq response
2) able to be put in a box producing moderate or smaller Qtc
3) pistonic action- ie: no cone flex
4) good excursion P2P (point to point) in the 'linear' range (ie: the Bl product doesn't fall too far [71%?])
5) power handling

-sure the nitpickers will want faraday coils, but i'd take one without.

for example, some 'very' efficient and small box designed "SPL" subs don't go deep at all. Some, no matter the box size, can't be made to have a Qtc of under 1.0 (ie: not tight bass). The shiva is not one of these.

Anyways...

For the spec lovers, their Fs is 21hz,

here's some numbers for the math/fact lovers out there:

[IMGDEAD]http://www.hakalugi.net/misc/shiva.gif[/IMGDEAD]

Remember, in reality, a driver can go both "low" and "loud" - just don't expect it to be in a small enclosure doing so.

You'll note that most of those are 'home' subs. A 'car audio' market sub that would best the Shiva (based on Vd) is this one: (the 12" Mass by audiomobile)

[IMGDEAD]http://www.audiomobileinc.com/images/2010s-ani.gif[/IMGDEAD]

You see the "little brother" Evo on line 3 in the table above, but even that one (at $199) can't best the $115 Shiva. The one with the fancy graphic will. But for the $329 it costs.... get 2+ Shivas and it's all over.


[ps- i do not own shivas.]

edit- added the name of the Mass.

[Edited by hakalugi on 11-19-2001 at 04:19 PM]
 
Re: Re: Deepness?

hakalugi said:
If they put out good SPL numbers, they put create pressure. I don't know of any difference between 'pressure' and 'spl' - in how you describe him using them... I thought they were the same, or rather, SPL is a measure of sound pressure. The 'depth' has to do with freq. response of the output- and the shivas are definitely not lacking there. You friend should download the datafiles on the drivers from AdireAudio and model the curves himself. (or maybe he's trying to justify the $$$ he spent on his subs ;-) )

eat that craig! =P
 
The Shivas are perfectly capable of going deep; my HT sub is 6db down at 16hz...

As for the SPL's, well, a single shiva can more than hold its own. During several passages in a number of DVD's, the Shiva driver was pushing out DEEP notes (sub 20 hz) with such high SPL that the enclosure was hopping up and down, and that was with a mere 200 watts pushing it. Now take TWO of those drivers, and factor in cabin gain... dual Shiva's will more than suffice for any amount of reasonable (or unreasonable for that matter!) music that you will be playing in your car while you're still in it :D
 
To make a sub "hit deep", you simply have to design an enclosure for it in the same manner as you would for home use, except using the proportions necessary to fit inside your trunk. Just make sure the enclosure is heavily braced, and if you use a ported enclosure, that the ports are front-firing, so as not to be blocked by your back seat or back of the trunk cavity. If you have test equipment, you can measure the response levels and use an equalizer to achieve better response.

Also, flat response is *desired* in all frequencies that your subwoofer reproduces, particularly the lower octaves. There may be some confusion here between a flat response and "one note bass." A flat response means that you will achieve fairly linear distortion and SPL's until you reach your cutoff frequency. Most inexpensive car subwoofers don't achieve flat response, nor do they have low cutoff frequencies. These poor attributes often attribute to that "one note bass" villain which claims so many of today's poorly designed car audio systems (excluding competition setups, which are designed intentionally for that purpose.)

Also, a friend of mine has a pair of inexpensive Sony X-plode amps powering his twin subwoofers, and he's yet to have any failures or problems with them. They put out more than enough power for his fairly inefficient drivers, and are more than suitable for tolerable listening levels.
 
Re: car?

Thunderbird said:
How do i make sure the subs hit deep in my trunk?

read this: http://www.installer.com/tech/aiming.html


Thunderbird said:
Isnt it 'bad' if the response at lower frequencies is flat?

in theory, yes. the idea with a sealed sub in-car is that, the 12db/octave roll-off is somewhat countered by the cabin gain.

here's what a shiva in a sealed box looks like anechoic (yellow line) vs. green line (ported low):

[IMGDEAD]http://www.hakalugi.net/misc/shiva3.jpg[/IMGDEAD]

your car will fill in the natural slope off...



Thunderbird said:
Also, are sony amps trash or quality? I dont know of anyone that has one...but it seems to be the only one that i can afford that has the features and enough power for my subs..

it is plenty of watts per dollar. goto the forums like: carsound.com, soundillusions.net, sounddomain.net, elitecaraudio.com, and do a search on the model #, then ask around for customer testimonials. i have nothing against Class D. At such a deep discount my main sticking point ($$ spent on kewl paint and graphics in flating cost) is moot. But there is the question of $$ spent on paint and graphics over parts/build quality. whomever you buy it from, just make sure they (at least) offer a 1 yr. (retailer backed) return/exchange policy.

and if it's "1 ohm stable" running 2 shivas at 2 ohms should be fine.

give it a try

[Edited by hakalugi on 11-27-2001 at 10:02 AM]