Type-r's keep blowing!

[75MonteCarlo 10+ year member]

Hey all, well I had 2 type r 12's in a 4th order bandpass, and I didn't bother to break them in, and I bumped them as hard as they could go for about 2 weeks, and then one of them blew on me, cracked the cone real good and detatched the spyder. So anyhow, I got that one replaced for free and bought a prefab box just so I could get some bass until I can afford to build a cutsom box, or go with a tcab. Anyhow the prefab is built to spec for the drivers pretty well. its ~1.7 cubes per side, slot ported, im guessing tuned to 35 or 40 Hz, with seperate chambers for each sub.

Anywas, I put the non-blown type R along with the new type R into this box, and this time I break them in for a good hour or two at least of playing time, being loud, but not pounding hard. I gradually worked my way up in volume until I had them bumping real good these past two days because its been melting out, and I know not to bump subs hard when it's freezing cold outside. Anyhow, all goes well for a while, these things get nice and loud, shakes everything in the car, blows my zippo out when I try to light a smoke, and i'm quite happy. Then today (2nd day of playing them loud) one of them messes up and startes making a clicking noise that I could hear in the car.. so I get out and watch, and its the older sub that was in the old box with the one that blew. Sure enough, its not getting as much excursion as the replacement type-r, and its making this clicking/clacking sound on all the beats. The port also smelled like burning electronics.

Here's what i've got powering them: A Rockford T10001bd amp, birthsheet says 1440 rms @ 1ohm. Both subs are dual 4ohm V.C. and I have them wired in series down to 1ohm, so they should be getting around 720 rms each. Now I know that alpine recommends 500rms, but what i've read on here, and from what people have been saying, these things should be able to take 720 daily with no problem. Am I wrong? Is there something i'm missing here that could be causing these subs to blow on me? I have the gains on the amp turned down to about 70%, and they sound like they're set correctly, plus I have the HU Bass level turned down to -3, so I should not be clipping the power.

What is causing this? Or do I just have really bad luck and i've gotten two bunk subs?//content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

Click to read more...

 

[Chevyaudio 5,000+ posts]

You need to set your gains with a DMM. sounds like you might be sending that amp into clipping.

 

[vosschs 5,000+ posts]

gains ay 70% seems pretty high i think.... but what do i know

 

[Lakota 5,000+ posts]

How high the gain knob is turned up varies in different applications, so 70% or whatever doesn't really say much. Sounds like you have been clipping the subs.

 

[SBLAZER]

maybe u are clipping the subs and playin them below tuning, causing them to blow. i say put ya gains half way and adjust bass boost on HU accordingly. not a bad setuo u have. u shouldnt have a problem wit em on that power. wha electricals upgrades do u have?

 

[75MonteCarlo 10+ year member]

Well I definately blew one, it put the a massive circular crack in the center of the cone with cracks spidering out from it, looking like a chipped windshield on my sub..

Electricals, nothing. I have plans for a 200 amp alt in the excessive amperage group buy, and i've got a motomaster eliminator spiral cell batt (basically the same as an optima) oh and i've got a lil 0.5 farad cap on there, just leftovers from my first system.

I noticed one thing tonight: the subs bump when I switch tracks, and when I turn on the HU. Also, if I have the volume all the way down, and the remote punch turned all the way up, you can't hear any music or beat, but the subs will slowly start making a sine wave.. i'd guess around 35 hz or so, and they just buzz (at a decent volume, loud, but not pounding).. I was talking to a guy tonight who told me that the new rockford amps are subject to power surges, and that I was probly getting power surges to my subs.. But then half an hour later he told me about a guy he knew that hit 300 dB with 4 juggernauts.. so i'm not sure if he knows what the **** he's talking about.

 

[Pyro_By_Nature 5,000+ posts]

In rare instances bandpass boxes have been known to kill subs.A lot of extra pressure on the cone..... My guess is that's what happened to them.If the spider became deteched even partially it'll sound horrible.Just an annoying clicking.

RF amps subject to power surges? lol riiiiiiiiiight.

 

[iagrdshaka 5,000+ posts]

The enclosure along with the clipping led to their demise. Im sure most woofers can take clipping and not blow, but that enclosure added more stress, till the woofer couldnt take it.

 

[theCybe 5,000+ posts]

^ as above, this likely has little/nothing to do with gains.

Either the SSF was improper (or nonexistant) or as noted, the enclosure pressure was too much. I'd like to see pics - you said the cracks start from the center of the cone? Be a hell of a hit to make enough pressure to crack it w/ air through the VC former, likely stress on the diaphram cracked it.

 

[Raven 10+ year member]

Type R's use a special motor cooling technology. It's really dependant on cone movement, so they don't take clipping at all. Combine that with a bandpass enclosure that really restricts cone movement, add them being overpowered AND clipped, and you have a perfect formula for a dead Type R or two.

 

[Raisedin305 5,000+ posts]

they're type r's thats why

//content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif I knew some one was going to say something stupid like this when I opened this thread, jump off the bandwagon...
Anyways, if you have your amp set how it was when you blew them get a DMM and check your gains and let us know what it reads.

 

[406er 10+ year member]

in a stupid band bass box thats tuned high and posable over doin it on the gain plus no SSF. and some lows i think your over-excurted your subs

 

[JimJ 5,000+ posts]

i think your over-excurted your subs

I highly doubt he went past Xmech in a 4th order BP...

 

[406er 10+ year member]

^^^^

just an idea

 

[Raven 10+ year member]

SSFs are not needed in bandpass. SSF are just to keep the woofer from going over xmech when playing under tuning. They are NOT needed in an enclosure that's purpose is to limit excursion.