Adire Vs. Id

Discussion in 'General Car Audio Discussions' started by PolkMM, Mar 11, 2004.

  1. PolkMM

    PolkMM Full Member

    on your package deals you have 2 brahma 10s for $670, but you sell them individually for $330
    am i missing something?
    does the $330 not come with free shipping?
     
  2. PolkMM

    PolkMM Full Member

    and i was just wondering on the kodas b/c im putting about 200 watts on my momos crossed over at 50Hz, but they dont have near the x-max as the kodas.
     
  3. sandt38

    sandt38 Full Member

    Monthly special :) forgot :). My bad, you are correct. All Adire Car Audio now comes with FREE shipping in the lower 48 states.

    The Kodas will positively scream with that amp. Be a bit more modest with the gains, but the low extention will blow your mind. 100 watts will get them hammering like SOBs :blowup:
     
  4. PolkMM

    PolkMM Full Member

    the brahma 10s sensitivity is 82.3, but at the bottom it says "This is true reference efficiency; for voltage sensitivity at 2.83Vrms, add 3 dB for series (4 Ohm) wiring and 9 dB for parallel (1 Ohm) wiring"
    what does that mean?????
    -Cody
     
  5. nismo

    nismo Full Member

    short story long... :oops:

    2.83v @ 8 ohm is 1 watt...that is true reference efficiency. 2.83v @ 4 ohm is 2 watts (or +3 dB from reference efficiency). they rated it this way because a lot of companies will rate at 2.83v or at .5 meter to make their efficiency appear 3 dB higher. its a common misconception amongst n00b's that more efficient subs are louder, so its just a way of cheating the ratings. anyhow, the way to tell if your ratings are cheated, is if it says "sensitivity @ 2.83 v" and the driver is NOT 8 ohm. if it says "sensitivity @ 1/2 meter" then likewise its rated incorrectly. on 4 ohm speakers it should say "sensitivity @ 1 watt" and possibly include "@ 1 meter".

    that being said, efficiency ratings mean very little, because they change with excursion. if Bl is completely linear, doubling power would add 3 dB, but because most motors are still conventional topology when you double power you DON'T get 3 dB.

    what does this mean for you? well if you have a low efficiency driver like the brahma 10 @ 82.3 @ 1 watt vs. another sub thats say 85.3 dB @ 1 watt...and you move up to normal power levels (say 250-500 watts), the brahma may very well be MORE efficient due to less loss of motor strength -- thats the benefits of Bl linearity. that way, you end up with more output for your dollar.

    moral of the story: DON'T HANG ON REFERENCE EFFICIENCY BECAUSE THE RATINGS CAN BE WRONG AND Bl LINEARITY IS MORE IMPORTANT!

    eric
     
  6. sandt38

    sandt38 Full Member

    Thanks Nizzy. Excellent explination. You saved me alot of typing :p
     
  7. PolkMM

    PolkMM Full Member

    I thought the sensitivity rating DID mean it was louder...I mean I know theres a lot of other things to factor in, but thats interesting. So I really shouldn't pay attention to that? I know the ID Max 12" has a sensitivity rating of around 93. I couldn't find what the 10 was but I assumed it was around 90. I was thinking that if I put 1000 watts to each ID it would be almost as loud as the Brahma with 1500 watts going to it. Sorry for my ignorance...lol
    -Cody
     
  8. BlkX

    BlkX Full Member

    It does make a difference...

    The IDMAX would be louder with less power more than likely, but you sacrifice box size when comparing it to the brahma. The brahma definitely needs more power, but you can use a much smaller box (probably .5 cu ft vs. 1.0 cu ft if comparing the brahma 10 to the IDMAX 10). 2 IDMAX's with 1500w would probably be louder than a single Brahma with 1500w....theoretically it will be.
     
  9. sandt38

    sandt38 Full Member

    Nonsense.

    The Brahma will get louder with 800, or 1500. The Brahma doesn't "need more power" either :rolleyes: . The Brahma will hammer along with 1000 watts very easily, and 600 watts as well. Nizzys explination of BL linearity say enough in this regaurd I think.

    Doubt it?

    Where's Geo? He's heard both Networkguy's IDMax and Brahma... I know Networkguy's opinion, and I am sure Geo will back it up.

    You cannot take a single number like Sensativity and say "this woofer will be louder" without a better understanding of the other numbers, and what they mean. You also cannot take a number like that and say it will be louder no matter what power you give it... this is such a sweeping generalization it is not even funny.

    Sensativity, Cody, is really a BS figure. It can be manipulated to look like whatever the Mfg wants it to be... Please recall Nizzys answer:

    Bear in mind that even if the # were factual, that how loud it is depends on a whole lot more than sensativity. However, a very efficient driver will require a larger enclosure... so that is 1 thing to remember when looking at that figure ;)
     
  10. PolkMM

    PolkMM Full Member

    is the brahma a dual 2 ohm speaker?
    I'm asking because if I want to get this sub later this year I'll have to be able to wire it to 4 ohms
    -Cody
     
  11. geolemon

    geolemon Full Member

    The IDmax was impressive, in that it had the output capabilities of two IDQ's on the same amplifier, both in medium-sized sealed boxes...
    We had about 1200w going to the IDQ's (which is much more than they were rated for at 600 each, but they took it daily), and temporarily swapped the IDmax for them, same car, same amp.

    Honestly, they sounded quite similar, which is impressive, two 12's replaced by one. ;)

    Unfortunately, it was a while ago that I heard the IDmax, and it was an older generation of the IDmax.

    The Brahma IMO sounds better, more realistic... but realistically, either would be appropriate in even an SQ competition vehicle.
    There's no doubt the Brahma has more linear excursion.


    The question of "which subwoofer is more efficient" really isn't an issue, because a driver's efficiency doesn't hold much relevance.

    YOU control efficiency, because YOU control what enclosure you put the sub in.
    I could take a Brahma, and design an enclosure that it would reach full output with 500 watts, and I could conversely design an enclosure for the IDmax that would require more than it's thermal powerhandling for it to reach full excursion. ;)
     
  12. geolemon

    geolemon Full Member

    I actually didn't read this thread before...

    I generally avoid threads that concern two subwoofers, with a "vs" in the title. B)
     
  13. sandt38

    sandt38 Full Member

    It is a dual 2 ohm driver, and don't worry Cody, it is a fairly efficient driver
     
  14. PolkMM

    PolkMM Full Member

    Thanks a lot for everyone's help...I've decided to go with the Brahma...and sandt38, ill be hitting you up sometime b/t september-december of this year for a couple of 10s
    thanks again!
    -Cody
     
  15. chadillac3

    chadillac3 Full Member

    It is a dual 2 ohm driver, and don't worry Cody, it is a fairly efficient driver [/b][/quote]
    I guess that depends on your definition of efficient...

    The one major knock in the ME/CA&E (can't remember which one) was that the Brahma is quite inefficient.

    Even Dan Wiggins has said that this is the tradeoff they chose to get the super small box performance with a great low end. IIRC, he basically said something to the point that power is cheap nowadays, so they decided to compromise in that end.

    IDMAX has less low end and needs a much larger box, so as a result it is quite a bit more efficient.
     
  16. flawlesskid

    flawlesskid Full Member

    I think we will all agree that enclosure determines efficiency for the most part, but 2 different woofers, similar allignments, and same power, are you telling me that driver efficiency is still a non issue? I highly doubt this to be true. Give the brahma an enclosure built to a .707 allignment, and do the same for an idmax. Give them the same amount of power, and i'll bet that the IDmax would be the louder woofer. I'm sure you can build an enclosure to make the brahma the louder woofer, but with all things equal, driver efficiency matters if comparing is what you're doing. Driver efficiency as a deciding factor aint worth it IMO though.
     
  17. BlkX

    BlkX Full Member

    I think we will all agree that enclosure determines efficiency for the most part, but 2 different woofers, similar allignments, and same power, are you telling me that driver efficiency is still a non issue? I highly doubt this to be true. Give the brahma an enclosure built to a .707 allignment, and do the same for an idmax. Give them the same amount of power, and i'll bet that the IDmax would be the louder woofer. I'm sure you can build an enclosure to make the brahma the louder woofer, but with all things equal, driver efficiency matters if comparing is what you're doing. Driver efficiency as a deciding factor aint worth it IMO though. [/b][/quote]
    This is my point exactly. Enclosure size will ultimately determine the efficiency of a driver, but given the manufacturer's recommendations, the IDMAX will be louder. Sure you can change the box size and have the brahma murder it, that's easy.

    A perfect example is Courtney's w7 setup vs. my w7 setup. Mine's in a 1.7 cu ft sealed box and his is 3.0 cu ft ported. We both have relatively the same power (i may give up 1-200w to him), but the output is far different. I'd be willing to bet he's at least 6-8db's louder than me, 10-12db's louder wouldn't be surprising...

    I'm speaking solely from the standpoint of having both drivers in a .707 alignment as Courtney said.
     
  18. geolemon

    geolemon Full Member

    As far as the same alignment... that could be true.. or not, we don't really know.. but the IDmax having a higher Fs, and known tighter gap tolerances might support that theory...
    The IDmax only having a 2" former compared to a 3" former of the Brahma however might just as well mean less winding length suspended in the gap, which would be advantage Brahma. ;)

    So I don't want to venture a guess either way...

    But I generally don't look at things by alignment so much as box size...
    That definitely isn't to say I don't look at Qtc with interest, because I do...

    But to me, my mindset isn't like:
    "Sub A, in a 0.707 alignment is an enclosure of ____ cu.ft., an F3 of ____hz, and has an efficiency of ____ dB (at ___hz)."

    Rather, I think like this:
    "Sub A, in an enclosure of 1.5 cu.ft. has an alignment of ____ an F3 of ____hz, and has an efficiency of ____ dB (at ___hz)."

    And with respect to that...
    Networkguy was the one who's IDmax we swapped in to see how it compared to dual IDQ's... he had a sealed box, I don't remember how large...maybe 1.5-2.0 cu.ft.

    He later purchased a Brahma to replace the IDmax, and it exceeded the IDmax in all ways - in that enclosure...
    It was louder, on the same amp.
    It did extend lower.
    It did sound more realistic.

    That's how I know they compare... but there's no doubt that the Brahma, in that same enclosure, must have been a lower Qtc alignment. I wouldn't personally consider that unfair. ;)
     
  19. flawlesskid

    flawlesskid Full Member

    Personally, i'd expect a brahma in an enclosure almost twice the recommended enclosure size to be more efficient, thus possibly or rather louder than the idmax. I'm not partial to either, so thumbs up to whichever works best..

    Also, i'd like to think that not considering qtc when comparing woofers A and B would likely turn out to be unfair to one or the other. As stated, box size determines relative efficiency, so it has to be considered if you're gonna compare. Sub A in the same enclosure as Sub B is gonna cause an unfair comparison.
     
  20. sandt38

    sandt38 Full Member

    I am saying just that Cort...

    BL linearity is the reason. Motor strentgh will not fall off with a flat BL driver like it will with the typical parabolic driver. Look at the BL curve, it is easy enough to see. Referance efficiency at 1 watt means zero when we get to 500 wattts and motor 1's BL is falling off while motor 2's BL is still the same. Lemme ask you, how often do you drive down the road listening to your driver with 1 watt?

    Chad,

    Smaller enclosure size always means the driver is less efficient. There is always a tradeoff. However, I wonder if you have ever had your hands on a Brahma. Without ever having had the ability to use one of the drivers and experiment with it (because quite frankly there is no other driver with it's ruler flat BL) you will never be able to understand it's behavior. Motor strength in a ported box is MONSTEROUS at tuning. I had to weld a steel plate below my trunk floor to stop the trunk from flexing. This strength is massive through it's excursion. Unloading is immediate and rather surprising. Sealed box strength is obviously similar. The flat motor strength also creates added efficiency at higher excursion as well. The driver is so easy to use, so forgiving in box size/type/power/etc. it is impossible to make the assumptions you are making without laying your hands on 1 and playing with it.