95Honda

Would you mind elaborating on that more? OK, and dammit sticky this or something because this is getting ridiculous these days... LOL... The voltage gain of an amplifier is the ratio of voltage applied to the input vs. the voltage produced at the output. This is expressed in db. An average voltage gain for a high power sub amplifier is somewhere in the vicinity of 30 db, or 5x the voltage doubling. This would mean that if the amplifier was presented with 2V on the input, it would present 64V on the output. You need to remember that audio amplifiers are voltage sources, they attempt to maintain a fixed voltage level into different impedances. Try not to forget this, it is important. This is why amplifiers have different power ratings at different impedances, because the rails will always try and swing the same voltage with the same input, and then the output stage will source the differing amounts of current required to maintain the constant voltage into the varying impedances. Ok, so we understand that amplifers are a voltage source. So now, lets look at an amplifier without a gain knob, like many older amps and most home audio amps. They have a fixed voltage gain (this is published when usable specs are actually given by manufacturers) and if we know what the voltage gain is, we know exactly what input drive will produce full ouput power into any impedance. We know this because if the amplifier is rated at say 100 watts at 8 ohms it has 29VRMS output capabilty before the rails are exhausted and clipping sets in (square root of W*Z) And we know if the amplifier is rated with 30db of voltage gain that roughly 900mv on the input will produce 29V on the output and is the maximum power (900mv * 30db = Apr. 29V) Now lets look at the amplifer with a gain knob. I has adjustable voltage gain. They usually give you around 10-15db of adjustment in overall volatge gain of the amplifier. Why isn't it expressed as db on the knob? Because most people wouldn't understand how db relates to voltage (a 6b increase doubles the voltage). So instead, they do the math for you and write a voltage level that cooresponds to the gain amount (like 200mv to 8V) and put that on the amp so you can set the voltage gain of the amp. Why do they do this? #1 so you can match multiple outputs of multiple channels/amps. #2 to increase the S/N ratio. #3 as a marketing gimmick..... #1 is easy and needs no explanation. #2 is also easy, but I will explain. The more voltage gain an amp has, the more it amplifies everything. This includes alternator whine, white noise (hiss) and everything else. The less volatge gain the amp has, the less it amplifies everything, including all of these noises. So, the lower you set the voltage gain while still being able to get the power you need out of the amp (you have sufficient voltage drive from your source) the less overall noise the system will have. This is also where matching the H/U output to amplifer gain comes into effect. #3 Would most people on here buy an amp with a gain knob or without one, if everything else was exactly the same? Think about it.... The most expensive amplifiers in the world do NOT have gain knobs. Look at any Krell, Mark Levinson, Pass Labs, etc and you will see this..... AND DAMMIT, speakers don't care about clipping.... If you are listening to any Jimi, Metalica or G-n-R, you are listening to clipping, and alot of it.... And I bet your speakers are doing just fine.... Speakers don't like too much power, that is what kills them. It kills them thermally if the enclosure alignment permits, and kills them mechanically if the enclosure alignment permits... That's it... That's all...

The speaker doen't cae if it is a clipped signal or unclipped, power is power and heats up the voicecoil the same. 100 watts of any signal is 100 watts. I have tested this. Thoroughly. The gain knob is simply there for matching H/U voltage drive and decreasing the system noise floor. The gain setting of an amplifier simply sets the voltage gain, nothing else. If you have a 1200 watt amp, it can put out 1200 watts, reguardless of gain setting. If it puts out say, 1200 watts at a certain setting, and you increase ANYTHING ANYWHERE in the signal chain, you will drive it into clipping. It is much simpler in every aspect than everyone makes it out to be.

I think it set me back almost $2K. The chassis was almost $500 with all the aluminium (that was over $100), stroke-sanding and anodizing... But to buy something like this new would be at least $5K+, so it works out in the end......

This type of crap is what helps people ruin their equipment. If you don't have something informative to offer, do not post anything.

Nothing changes in the motor. There is NO conclusive data on break-in as far as damage... In other words, people don't really know what they are talking about... Let it rip or take it easy, it won't make a difference.

No problem. Glad it worked out for you. -Mike

PM me your phone number.

Are you going to try both subs in the exact same box or are you going to try them in the same alignment?

You can kill that sub with that amp. Don't send more than 900 watts to it in your box. There isn't a single person on here (so far) who has completed an objective power measurement on this amp (and no, clamping the amp in your car with a sub hooked up is NOT objective), so all of this "doesn't make rated power" BS is all heresay... Don't pay attention to it all...

Well, yes, that makes all the difference.... With that box and tuning, anything near 1000 watts will more than likely damage the woofer a few Hz below tuning and anywhere in the 40-60Hz region. So plan on a SSF and limit yourself (you really have to do this on your own!) to around 900 watts. If you are worried you can't limit the power to 900 watts, buy a less poweful amp and don't overdrive it, or buy a 450 watt amp and do whatever you want and not hurt anything.... And be almost just as loud....

It all depends on the box. And no matter where the gain is set, you can get full power out of that amp.....

Additionally, nobody knows what the "rated" power is of that amp, Hifonics doesn't list it. All they say is 2600 watts RMS. This doesn't mean anything. It could be rated at 10% THD for all we know, and in that case, it probably makes it's "rated" power. Again, tough to say with this kind of amplifier and advertising...

You won't see many, if any objective power measurements on this or any other car audio site. If anyone measures the power output while in a car and hooked up to a speaker, it is meaningless. It puts out what it should for the price...

Is this a joke? Seriously, you need to read those white papers and go through Martin Kings site before you waste more time or damage your drivers. They spell everything out. Especially the kind of line dampening to use. This is absolutely NOT how you dampen a T-line...

Download WINISD or Boxplot 2.0 Run the numbers, then double check back on the site with your results. You'll never figure out how to do any of this if you don't attempt some on your own... Also, don't use particle board... Ever... It really sucks both acoustically and structurally....

The T/S are done with small signal analysis. It won't change them to measure the coils in parallel.

Should be fine.

You'll notice, I am one of the only people who has consistently said the opposite... Also, I have always stated the opposite.... Additionally, a driver like the BTL (in the correct alignment) will always produce more SPL at any given voltage than an innefficient alignment such as Bob's little sub... I have always seen the direct proportionality of Le to back EMF. You traditionally see drivers with permable core metals, shorting rings and short voice coils have lower Le and Back EMF. I completely understand what back EMF (voltage) is and why it is produced. I know how an armeture works. I also understand what makes it worse. I also know what mittigates the problems associated with it, and what exaggerates the problems... You don't have to agree with me, that is why this is a forum. We aren't arguing either, we have different points on this. Don't take it personally...

Read the white paper(s). 30Hz? Shoot for 5-6ft stuffed. Finish at Sd. Start at 1.25x Sd. That's a T-line... If you aren't stuffing, it needs to be alot longer than that (A LOT longer), that is why ALL proper T-lines are stuffed.... T-Lines ARE NOT for SPL, there are NOT as efficient as a ported enclosure above resonance....

The gain setting will not limit your amplifier output, you still could be using every watt that amp will make... The sound difference between sealed and ported is non-existant assuming both are aligned properly. A ported box has the potential to have more output for an octave or so below tuning vs a sealed box below resonance. As far as sound quality, you'll have about a 1000 opinions, and none of them really matter. You have to try and hear it for yourself....

How much are those?

Were both lines on each side of the woofer the exact same length? If they were, they were cancelling each other within the pass band of the line... I didn't realize until I saw the last pictures what you were actually doing.... You had 2 identical outputs, about 1' from each other 180 degrees out of phase.... Not a good thing for much below 80Hz or so..... Trying building a straight forward 1/4 wave stuffed line.... Then you will hear what a T-line is supposed to sound like... You'll lose alot of efficency making a bandpass with a T-line on one side vs. a standard port do to line loss...

Here is a link to a big carpeted build I did a while ago- http://www.forceaudio.com/showthread.php?t=201&page=4

Don't ask questions on a car audio board about 1/4 wave line length.... Table 1 here gives you line length: http://www.quarter-wave.com/TLs/Alignment_Tables.pdf Notice driver Fs and bass boost aren't part of it. Seriously, if you are interested in T-lines, read this entire document....

It doesn't matter where you set your gains with a 5000 watt amp, you can still get well over 5000 watts..... There is no minimum power for any sub. Period. The more power you have the louder they will play with more non-linearities. The less power you have the less louder they will play with less non-linearities. The power required to get full output from any subwoofer is box alignment dependant and has nothing whatsover to do with the RMS rating...