95Honda

This type of thing should never be covered by the manufacturer. You should have removed the plastic cover from the back of the motor, this may have really been a big part of your problem....... I would just plan on sending in the driver for a recone, and paying for it.

I built a small vented box out of 1/4" aluminum about 4 years ago. I think the price of raw materials would be at least $200 now, not to include the 10 hours or so it took me to fabricate and TIG weld the whole thing together... Heavy Metal - Forceaudio

You gave the sub too much power, that is the only thing that can fry it like that. It has nothing ot do with gains, clipping, tinsel leads (it is a 100% myth that clipping hurts tinsels) or anything like that.... From some of your symptoms, it also sounds like the amp may have issues.... If that amp is screwed up, it could also be putting out components other than the audio you would normally hear (dc, HF oscilations, etc) and you could easily destroy the sub without even playing it loud.... But again, this is only because you overpowered the sub...

The cooling does have an effect on thermal capacity, a very large effect in some cases. But, this isn't really effected by the waveform, this is the point I am trying to make. In my test I chose 170Hz because that was the lowest frequency that could be used that would be able to thermally fail the drivers within 1 minute and drive the speaker to its full excursion limits. At 20Hz mechanical failure set in within roughly 5 seconds at the power levels used in the test. One of the big issues is that a speaker can't even produce a square wave anyway. It doesn't really start and stop as quickly as people think, there is ringing and dampening involved. When you get up there in frequency even a square wave has the cone moving back forth alot more linearly than you may think. Put your hand behind your pole piece driven with a sine wave and then a square wave. You can feel the same amount of air movement..... All the cooling tricks that are used still work fine when anything but a sine wave is played. This is the nature of the beast so to say... I am not on the tech team anymore because I had asked a while back to be taken off because I didn't have the time to be on here and one jerk off in particular (not any of the staff) really pissed me off... Lol.... I am really busy and don't often have the time to be on here... I'm waiting on a flight to Afghanistan at the moment for a few days of electronic systems troubleshooting they need me to do and then I'll be back around.... I can elaborate more at that time. -Mike

Like I said, some people will never understand this..... But hey, I am not going to argue this point anymore in this thread.

No it doesn't effect cooling, in the slightest. I did a complete test on it here- The Clipping effect test - Forceaudio Most people don't understand this......

Again, there is nothing wrong with pushing an amp 100% beyond it's limits (full clipping) as long as you don't exceed the continuos thermal rating of the voicecoil. A speaker doesn't know or care what waveform it is given. Where people get into trouble is if they have an amplifier that will put out 1000 watts RMS before clipping and they connect this to a subwoofer that is rated at 100o watts RMS. When driven into clipping, the amplifier produces more power than 1000 watts (the 1000 watt rating is given when producing a sine wave) duw to the different waveform(s) it is producing. This is what causes the thermal failure, the increase in power, not the clipping. If it took 1500 watts of a clipped signal to blow the sub, the subwoofer would have blown just as fast if it was connected to a 1500 WRMS amplifer that was at full power but not clipped..... People just forget this fact and blame every burnt coil on clipping, when in reality, it has nothing to do with it. Think of it this way, when manufacturers rate an amplifier, they (hopefully) rate the output power while producing some sort of low distortion sine wave. Now if they rated the same amplifiers while producing a square wave the numbers would increase, they may almost double depending on the power supply..... But still, if you had an amplifier that was rated to produce a 1000 watt square wave, it would never blow a 1000+ watt RMS speaker unless the speaker manufacturer fudged the power ratings, or they were not based on real world constant power. When you have amps that are over 1000 watts it's real easy to blow a sub. There really aren't many, if any at all, that can truly handle 1000 watts, indefinetly.... Some things heat up really slowing, especially if they have very effective cooling means, but eventually, you can almost always cook just about any sub.... And most people blame this on clipping when really, it is just not the case...

If the sub is truly rated at 1000 watts RMS, even with a 500 watt amplifier you could never blow it, even if you were a tard driving the amp into full clipping.... Clipping doesn't hurt anything anyway, it is too much power that fries a voicecoil. People don't realize it, but alot of music we listen to (especially some rock) is heavily compressed and contains large amounts of clipped signals.

You'll proably be just fine. I don't think the surround on those is anything spectacular. Just take your time.

I would look elsewhere. I don't think you could even get a kit anymore for that, and if so, it probably would be a small single ended amp. When you are talking that power, you are looking into at least push-pull with EL34s or something similar. Additionally, the dampening on tube amps (especially something cheap with a cheap output transformer) can be poor at those frequencies. I built hundreds of tube amps working for Audioprism/Redrose music in the early 90s. Buy a cheap plate amp and make a cool box for it if you want to go DIY. It'll work well and you'll be much happier.

No. It just means how far the cone can travel before something breaks.

I would still try and contact Orca/Zalytron. Those are nice subs, mine had that same motor on it. I would also post this on diyaudio.com, you might have better luck.

Honestly, you would loose pretty much most of the good things about that sub if you have it reconed by anyone other than Focal. I can't recall, but is that a polyglass cone? If so, that is pretty much the heart of that sub, everything else is pretty conventional. I am not sure if you can get a Focal recone, I would see if Orca still is around. Kimon Bellas used to be the guy for Focal stuff in the US, but I haven't dealt with him for 10 years. Google both Orca and Kimon and see what you get. I would also contact Zalytron, as they are one of the biggest Focal DIY importers... Good luck, and honestly I wouldn't go with anything but Focal softparts (if you can even get them). I have owned several of the Focal subs, including the original 15" Polyglass subs from 15 years ago. They are really nice, but again, geared tward something completely different that the places mentioned for recones in this thread...

Kind of on the first half, no on the measuring part. You can't measure the impednace with an ohmeter, only the DCR. To measure impedance the system has to be under power (can't test with an ohmeter with anything else connected to the sub) and you must either due this with an impedance bridge, current vs. voltage (not very accurate using cheap meters), a specific measuing device (Dayton woofer tester for example), etc.... Also, you can't ever wire up your subs to .5 DCR. The DCR will always be lower than the average impedance. For instance, if yuo have a sub with a nominal .5 ohm coil, the DCR will be lower, say .4 ohms, even lower maybe. Theoritcally, at some frequencies, you might be right down near DCR, so your .5 ohm sub could be presenting your amp with a .4 ohm or less load. Remember, when manufacturers spec out an impedance for a sub, it is an average....

Actually, a port (hemolitz resonator) and a T-line are not even remotely the same. A port works off of resonance, a T-line is non-resonant. A port has a tuning, T-line does not have tuning, it has a cut-off determained by physical length, wavelength and stuffing density. Kind of a big missunderstanding with T-lines....

There is no such thing as "Impedance rise". There is an impedance curve, and this goes up and down, so it rises and falls. Don't get hung up on "rise", because it is only the case half the time. The main things that cause your impedance to change is the different resonances the complete alignment has. You can calculate this using just about any of the modeling programs out there. They take all the things like box size, vent resonance etc into account when predicting impedance. But again, this is only a prediction.... The best way to determain your impedance curve, and more importantly the impednace at whatever frequency or range of frequencies you intend to use, is to measure this when the system is complete. If you are trying to get every last bit out of your amp at the very lowest impedance before it cooks itself to death, it would be nice to know what that impedance actually is. Another little tid bit, the overall impedance will never be below what you measure as DCR with an ohmeter. This is true at any frequency, in any box, at any power level. So if you read say 2.3 ohms DCR with an ohmeter, your system impedance will never dip below this....

I don't know off the top of my head, I also am not sitting at my home PC with BBPro, so I can't model for you. Just download WINISD or a similar program, it will help you learn a little along the way. Set the Qtc around .75 to .8 without any stuffing and see if that will be small enough for you....

There is absolutely nothing wrong with running 2 different amps on one sub. Additionally, matching the amps is trivial. It will not hurt the sub in any way if the signals are completely different. You will just have more loss the less they are matched in phase (shouldn't be an issue with 2 identical amps set the same). The only reason you match the level is so that each amp is running out of steam at the same time, that way one amp isn't already taxed while the other is at say 50%. In the voicecoil, no matter how you wire it, if the signals are in phase they are additive, if they are different levels, they are still additive. If they are out of phase they begin to cancel. This doesn't really hurt anything. The coil doesn "work against itself", instead the magnetic field weakened, or not built.... It doesn't overheat anything as long as you don't exceed the thermal ratings of the coil. There are literally millions of passive DVC home audio subwoofers around the world that have been operating on combined stereo signals (huge phase and level differentials) for decades without any issues.... As they should....

If you want it to sound good all around, just put it in a box with a Qtc around .7-.8. You might be surprised at how small it is with this driver... I have 2 of these exact drivers in my Home Theater right now. They are probably one of the lowest distortion 18" drivers with decent stroke ever made. Better quality than any of the newer XBL2 stuff from CSS, Exodus, etc.... They sound great sealed, in fact thier Qts is almost ideal for this....

You'll probably be buying new subs soon......

No, the magnets have nothing to do with XBL2. XBL2 refers to gap geometry (dual gaps). Many XBL2 drivers use single magnets. In fact, the Parthenon used single stack magnets, this was the highest stroke driver Adire ever built, the protoytpe I saw could do over 4" one way...

The amount of magnets have nothing to do with the "flux field". It is mostlty the gap/magnetic circuit (steel) part. More magnets are used for clearance, and a little (like more than exponetially dropping benefits) more flux, but again, not much. They are much cheaper than high flux steel, that is why you see 2, sometimes 3 or 4 stacked. It is lot cheaper to stack 3" of magnet than machine a 3" thick top plate. Lots of magnets also sell better, lol... All XBL2 subs are not bottomless designs, this varies from sub to sub and has nothing to due with "XBL2", it has to due with voicecoil clearance. Every XBL2 sub I have owned (a shit load) will reach mechanical limits, just not always the rear of the voicecoil former. I have shredded 4 tumults from the triple joint smacking the top plate, this is not bottomless. XBL2 reaps the benefits of a flat BL curve similar to an underhung motor. I personally think it performs better than underhung within the price range. But XBL2 also uses a shorter coil with less surface area and has lower thermal limits than similar overhung motors, but it does this with much less Le, which is a good thing.. The early XBL2 subs were low end monsters, but this really was primarily due to a really well suited set of T/s parameters for this. They had tons of clean linear stroke (1" more 1-way) low Fs and a mid Q. Add that all up and you get a sub that eats on the bottom, XBL2 helped keep the distortion low within the excursions limits. The lack of "high end" was usually due to the exxagerated low end and the fault of the end user.... Shorting rings and farady loops aren't fads, they have been used succesfully for many (like 20-30) years to lower Le....

Most of the time when someone farts around with a DMM trying "set thier gain" they have wasted time... Lol.. Then, if they think they have done it right, most of the time they have just given themselves a false sense of security and thier next thread is "My FI Q stopped working, how do I get my money back???" I am not trying to come off ass a smartass, it is just hard not to sound that way when you read this everyday on car audio forums for 10 years...... There doesn't need to be an article on this. The gain control sets the voltage gain of the amplifier. That's it. If you need more info, google "Amplifier Voltage Gain" there will be plenty of information there.... To be honest, these days at least, you don't even need a gain adjustment (as far as the sub amps are concerned) 99% of the time. It is just one more thing in the signal chain to foul up someone...... And if you are so running the ragged edge of power handling that if you ever so slightly drive your amplifier into clipping and this single event causes the slight increase in power to fry your sub, you have other problems and shouldn't blame this on snything but yourself...

It is just a waste of time. Especially if you only have one sub amp and are not trying to match a ton of amps.... Here is why- Most people have no idea what impedance they are setting the voltage gain of thier amplifier at, therefore they have no idea how much power the amplifier is actually producing... Most people don't have true RMS voltmeters Most people don't have a clue that the gain adjustment does nothing but set the voltage sensitivity of thier amp. They also don't have a clue that it was only put there by the manufacturer to overcome maximize S/N ratio and match HU output levels, NOT to "Keep anything bad from happening" Set it all you want, if you are a tool, you will still find a way to overdrive your subwoofer Clipping doesn't hurt anything....... Don't argue this unless you are willing to complete an in-depth test with accurate test equipment and publish your results as I have... If you can't tell when your subwoofer is overdriven by ear, and are putting faith in your "setting gain with a DMM" you need to buy an amp that has drastically less power.... Many of the posts I read dealing with this on here make it painfully obvious that many people have no idea how to use test equipment accurately/correctly Seriously, it is 99% mental masturbation with this on here. One amp? It's easy. Turn the F'n gain all the way up, especially if you have a variable subwoofer output on your HU. If you don't have a variable subwoofer output, you may not have to turn it up all the way, maybe just set it near the nominal pre-out voltage of the HU. Listen to music and don't overdrive your sub. That's it. It takes 5 minutes and no test equipment. If you can't handle this, you are out of your league as far as your equipment goes...

You've just wasted all your time. Like Adrian said, without a load it was meaningless. Also, without knowing if it is even reading true RMS, it is again meaningless using any equations. Additionally, without accurate measurement, you don't have a clue what impedance you are dealing with.... Everytime I read one of these threads it just makes me realize how much time people waste with this. Especially when you see numbers like 45.678 VRMS.... LOL...