Too much power 4 XXX6.5 RE's

I have been planning on running a JBL PX600.2 on a set of the new resonant engineering XXX 6.5" components. It seemed like a good match since the are rated at 150w rms and the amp puts out 180w(cea2006 rated). The specs for the 6.5's have been released and the are 2ohms. The amp is rated at 290w @ 2ohm load. I'm wondering if that may be too much for them. They are a really stout mid though. something like 12mm or 13mm excursion. they also require either a sealed or ported enclosure. I got all this info from RE and BladeIce.com. So would this bee to much for them?? This is a thread with a pic of the new RE line. Just scroll down to see the XXX 6.5 comp set. http://www.talkaudio.co.uk/vbb/showthread.php?t=59474&page=1&pp=25&highlight=xxxPioneer DEH-P980BT, Zapco DCREF1000.4,Pioneer TS-C520PRS, Adire Extremis, MTX TA91002, TC Sounds TC-3000 15"

It's only too much power if you turn it up too loud. I have no problem running my components with 2x their rated power, because I like something called dynamic headroom. Basically, audio is a complex waveform that is a series of large peaks superimposed on a small average voltage. The relationship between the two is called crest factor, and is expressed in dB. Most music I listen to has a crest factor between 3 and 10dB. For those not familiar with the dB scale in relation to power, that means at a constant impedence and frequence (not realistic but fine for this example) the amps will be asked to put out short duration pulses that are between 2 and 10 times the power. The IHF peak power measurements don't mean much to me because of the way they're tested (1kHz, 10mS pulse, etc). That peak power is required at low frequencies, and can put a huge amount of stress on an amp's power supply. By over-rating the amplifier compared to the "rated power" of the speakers, I ensure that my amps always have enough umph left over to reproduce those peaks cleanly and without any artifacts (slew rate limiting, current overload, etc). That said, if you're more interested in volume than quality, you can easily melt the voice coils of that system with the amp you're looking at. With careful application of judgement and a little bit of common sense it shouldn't be an issue. -daveThis is not a sig. This is a duck. Quack.

Underpowering with cheap amps kill speakers! Having a larger amp allows to to increase headroom and sound quality. Just be carefull in choosing x-over points, don't try to get 40hz out of a 6" in a door! Also loading down amps into stupid impedences just causes problems. I'm a pro audio engineer and run triamped systems using amps that are 2500W a channel into 1" compression tweeters. This is the amount of power recommended by JBL for these tweeters. The gains are turned down and haven't blown a single unit(@ $400 a diaphram) Quality power, headroom, and some common sence and you'll be fine. In my truck I'm running Zapco C2k-4 (x2) and a C2k-9.0 all on 2 pair of Quart QM comp sets and a single JL sub. No blown drivers, no distortion. Your JBL amp is a good choice. Good Luck!

This is true...clipping an underpowered amp is more likely to clobber a driver than too much juice, but either way can be used quite well if you take the time to set up your gains properly. Audiocableguy- I to am a sometimes PA guy, sometimes recording guy, and all the time electronics guy. "Overpowering" isn't required in this application nearly as much as it is in live PA work, simply because CDs doesn't have the dynamic range of a mic'd kick. The most dynamic disc I've ever seen, and I looked for a long time, only had 13dB of dunamic range on it, and it was a true rarity. Probably 85% of the mainstream discs have less than 6dB of dynamic range, and a cxrest factor even lower. Using a big amp with that kind of material is more likely to cool a voice coil or bounce a former off the backplate. Like I keep saying, a little intelligence when setting system gains, and more importantly, system gain structure, will take you a long way, no matter who you are and what you use -daveThis is not a sig. This is a duck. Quack.

those drivers are INSANE , i never seen anything that beefy for 6.5 ever............. everything stolen :(

Workin on a new system :)

Peace in the middle east

Well, correct me if I'm asking for too much here. I want to be able to go ride around with my girl and have the sound be clean. Of course it won't be at a high volume with her in the truck. I also want to be able to ride around with my friends and have it still be clean just alot louder since they will have to keep up with the 2 RE XXX 15's in the back. The 15's will be powered by a JBL 2200.1. There will be 2 RE 8's to go along with this system so I was thinking I could set the x-over's a little higher for the mids. I'm not planning on trying to set the gains by ear since it would be too much money to waste burning something up. I'll have to find a local shop with the tools to set the gains right. I'm choosing these 6.5's due in part to RE's rep and the fact that they use the XBL2 motor, which I'm sure Steve will like.Pioneer DEH-P980BT, Zapco DCREF1000.4,Pioneer TS-C520PRS, Adire Extremis, MTX TA91002, TC Sounds TC-3000 15"

dpaton, Yes I agree with you on the dynamic range of CD's and not needing the same headroom as for live music. The pro-sound example was used to show that maunfactures will suggest power that is over the stated handling for a reason. The amount of power over is dependant on the application. This shows that headroom is important and underpowering can be a bad thing. I'm not suggesting that a 1000 wpc channel amp is the correct choice for a 6.5" comp set either. If a set is rated for 200 watts, a 350 wpc amp is not sooo huge that it is a waste of money. The point is having addition power available and the correct gain structure can only help. As far as setting gains by ear, unless you are competing and it really matters, you should be able to get the gains pretty close.

T.Hill wrote: I'm not planning on trying to set the gains by ear since it would be too much money to waste burning something up. I'll have to find a local shop with the tools to set the gains right. I'm choosing these 6.5's due in part to RE's rep and the fact that they use the XBL2 motor, which I'm sure Steve will like.

Like was just mentioned, you can set the gains by ear pretty closely. The "best" way to do it is to make sure that everything in the signal chain clips at the same point, head, eqs, amps, so that you maximize both dynamic range and SNR. Not being able to do that with tools, you make some educated guesses about things (6V preouts into an amp with a min 4V sensitivity, turn the gain all the way down, use the level controls to bring up the quietest channels to taste) it shoudl be fine. If you've trained your ears to recognize the soudn of flat pink noise, you can use that. Otherwise take a piece of music you know really well and start form the bottom up at that you consider "loud enough" going from min gain to whatever sounds right on each amp. I only do one side at a time, just to make it easy, and then match it on the other side (pull one side of the RCAs from the head or the amps to acomplish this). -daveThis is not a sig. This is a duck. Quack.

Thanks for the info on how deep they are. I didn't have the information yet. I am taking off the bottom of my door panel and fabricating a new one just for these mids. It's already made for a 6.5" mid, but not one of this size. RE says that it needs .08 to .15 cubic feet for a sealed enclosure which is what I'll end up going with. It will also do a ported which is just insane for a component set. I haven't heard of the Extreme's that you talk of, but I'll go take a look at them. Thanks for you help everyone!Pioneer DEH-P980BT, Zapco DCREF1000.4,Pioneer TS-C520PRS, Adire Extremis, MTX TA91002, TC Sounds TC-3000 15"