help with crossing over eminence alpha 6a /apt80

[vj]

ok i have 10 eminence alpha 6a's and 10 eminence apt80 supertweeters in my truck. theyre not in yet, but soon.

whats the best crossover points for these? on the 10 alpha 6a's i will have a MA audio hk898 amp, and on the 10 tweets ill have a MA audio hk298. 5 on each channel running @ 1.6 ohm each.

what is the reccomended power to put to these? just go buy the manf ratings?

thanks for anyone here who can help!

VJ

[wg_ski]

> ok i have 10 eminence alpha 6a's and 10
> eminence apt80 supertweeters in my truck.
> theyre not in yet, but soon.

I sure hope you have some serious woofage to go along with these. The Alphas have about 10dB more output per watt than most "car" speakers do, and the tweets are another 10dB above that.

> whats the best crossover points for these?
> on the 10 alpha 6a's i will have a MA audio
> hk898 amp, and on the 10 tweets ill have a
> MA audio hk298. 5 on each channel running @
> 1.6 ohm each.

Xover at 2.5-3k, as steep as you can.

> what is the reccomended power to put to
> these? just go buy the manf ratings?

The tweeters can handle about 7 real watts of continuous power. Can be used with 25 watts of amp per tweeter actively crossed over if you keep it out of distortion. With the system Eq'ed for reasonably flat response, you won't be putting more than a couple watts into the tweets when it gets uncomfortable to listen to. They're 10+ dB more sensitive than the mids.

The A6's are good with up to 100 watts or so per unit if you're going all the way down to meet a sub. They'll distort from nonlinear excusrion before you can really hurt anything. You can hit them harder if you're using it as a true midrange (400 Hz and up).

The real unknown is how much power you really have. None of the entry level amps can put out their stated power. Some are inflated by a factor of two, others by four. The only thing you can really trust is your own measurements. Barring that, understand that 50 cents per watt is as good as it ever gets. If an amp costs $100, it can put out at most 200 watts, bridged, into the minimum impedance that it will drive.

> thanks for anyone here who can help!

> VJ

[vj]

> I sure hope you have some serious woofage to
> go along with these. The Alphas have about
> 10dB more output per watt than most
> "car" speakers do, and the tweets
> are another 10dB above that.

i have 4 15" subs with about 3500w rms to each...should be enough :)

> Xover at 2.5-3k, as steep as you can.

i never understood what people meant when they say "as steep as you can"

but set the crossover at 2.5 or 3k, and up?

mids: ? - 2.5/3k (where the tweets take over?)

> The tweeters can handle about 7 real watts
> of continuous power. Can be used with 25
> watts of amp per tweeter actively crossed
> over if you keep it out of distortion. With
> the system Eq'ed for reasonably flat
> response, you won't be putting more than a
> couple watts into the tweets when it gets
> uncomfortable to listen to. They're 10+ dB
> more sensitive than the mids.

the amp i have for the tweets (going by rated power) will be about 50w rms to each tweet, im going to keep the gains real low though on those.

> The A6's are good with up to 100 watts or so
> per unit if you're going all the way down to
> meet a sub. They'll distort from nonlinear
> excusrion before you can really hurt
> anything. You can hit them harder if you're
> using it as a true midrange (400 Hz and up).

what should i cross the mids at then? i dont want them to distort, i just want them to play loud. im not sure what im going to cross my subs at yet, but i know since i dont have midbass, i dont expect these aplha's to pickup where the subs left off. i know ill be missing those frequencies, and im fine with that.

> The real unknown is how much power you
> really have. None of the entry level amps
> can put out their stated power. Some are
> inflated by a factor of two, others by four.
> The only thing you can really trust is your
> own measurements. Barring that, understand
> that 50 cents per watt is as good as it ever
> gets. If an amp costs $100, it can put out
> at most 200 watts, bridged, into the minimum
> impedance that it will drive.

some amps do theyre rated power, some dont. i have to disagree with that, becuase you cant really say that about all amps, theres some amps that can be had for 400 dollars, rated at 1500w rms @ 1 ohm, and tests have shown 2k wrms + out of them.

[wg_ski]

> i have 4 15" subs with about 3500w rms
> to each...should be enough :)

That may be overkill - if you only have a couple hundred watts going to mids and highs. I'm using 2 ordinary 12's with four A6 mids and it gets to live rock concert levels.

> i never understood what people meant when
> they say "as steep as you can"

4th order or steeper. Those tweeters only have a 1" voice coil.

> but set the crossover at 2.5 or 3k, and up?

3k if you're going to blast it.

> mids: ? - 2.5/3k (where the tweets take
> over?)

I cross over at 90 Hz from sub to mid. The Alphas only make it down to about 90 before rolling off - and that's in a small ported box. If you run them sealed or IB you may need to prop up the midbass a bit.

> the amp i have for the tweets (going by
> rated power) will be about 50w rms to each
> tweet, im going to keep the gains real low
> though on those.

"Rated" power means wide band noise, run through a passive crossover. 1" VC horn tweets can handle 7 watts of power, period. 7 watts into those things is ear blistering loud. But using a larger amp for headroom is how you normally use them.

> what should i cross the mids at then? i dont
> want them to distort, i just want them to
> play loud. im not sure what im going to
> cross my subs at yet, but i know since i
> dont have midbass, i dont expect these
> aplha's to pickup where the subs left off. i
> know ill be missing those frequencies, and
> im fine with that.

90 Hz seems to work ok with these. I only feed them with 75 watts each and my ears distort before they do. If you REALLY want it to get loud and you need a lower crossover frequency, cconsider the Beta 8 midrange. You can hit them pretty hard at 70 Hz and not have a problem. And they're a little smoother on the top end, believe it or not.

> some amps do theyre rated power, some dont.
> i have to disagree with that, becuase you
> cant really say that about all amps, theres
> some amps that can be had for 400 dollars,
> rated at 1500w rms @ 1 ohm, and tests have
> shown 2k wrms + out of them.

Never seen that. IME, an amp that puts out 2000 watts costs 1000 dollars unless it's hot.