help me figure out what i did wrong

[kickass audio]

Alright, so i had a previous topic on here that was locked because nobody would stop spamming my shit. So before you think of posting if you are planning to post bullshit get the fuck out and post dump somewhere else. Im here to learn how to not screw something up not get this thread locked too. Thank You.

So here was my thread before it got locked. http://www.stevemeadedesigns.com/board/topic/130763-aa-smd-18-blown/page__pid__1845113__st__80#entry1845113 I am trying to gather all the information i can about what i may have screwed up or need to improve on before i put my system back together in 2 years. Any and all help that is related to this topic is greatly appreciated.

Just so you guys know how i set the system up. I did it exactly as follows:

1.) Set the eq on my radio completely to flat, loudness off, fade/balance to 0 and put my o-scope on the rca outs of the radio. Since i know the radio has 4v pre-outs i figured i was about the 4v ballpark for RMS voltage so i connected the alligator clips on my 440plus and then played a 0db tone to see what the radio would clip at first.

2.) When i was playing the 0db tone i could get the volume as high as 28 out of 35 before it would start to clip on my o-scope. Also what i did to really assist with noticing the clip was changed the refresh rate after i noticed a hard clip just like Steve showed in his old gain vids. To do this i pressed "t-base" on the scope and then pressed the f-key to "fast" until it was basically focused on just one peak and valley of the sine wave. That helped me fine-tune the volume to see truly what volume level was clipping at. Then when i went to test the subwoofer outputs on the radio i noticed that the voltage was super low so with my radio i could turn the subwoofer setting up all the way (15 out of 15) and not have any clipping as long as i didnt turn the radios volume up past 28. So i did exactly that and for the front, rear, and sub outputs i had a RMS voltage reading of 3.98v. Not bad.

3.) Now that i knew the radio would only go up to 28/35 i went directly to my 3sixty.2. I grabbed my laptop and set the eq on flat for every channel, turned the dbr settings up to 0, and made sure the crossovers were all turned off for all the outputs. I played the same 0db tracks i used when finding the clipping of my headunit. So i had turned the gain setting on the 3sixty.2 down all the way for all the inputs and grabbed my rca's and proceeded to use the alligator clips to put on the end of the rca so i could test it. I turned the gain on the 3sixty.2 up until i noticed that the 440 had a clipped signal then backed it off. And as noted before i used the t-base function to zoom in and inspect the peak and valley for any flat lines and it was free. (note: i noticed that the clip light on the 3sixty.2 was spot on to when i noticed the peak and valley starting to get a flat line so i was double sure it was good so far). I repeated this step for ALL the rca's coming out (left front, right front, left rear, right rear, subwoofer, center) until i knew that all the rca's were nice and clean.

4.) Now i moved onto my amps. I removed the alligator clips from the 440's probes and then inserted them into my mids/highs amp. I made sure the amp was set to full-pass just like my 3sixty.2 and that everything was still on a flat-eq setting. I barely had to turn up the gain on the amp itself due to the high voltage output that the 3sixty.2 gives so it didnt take me very long to find where the amp would clip at. So i did that for all the channels of my mids/highs amp. Then i moved onto my sub amp. Same thing, eq on flat, subsonic set all the way down and lowpass set all the way up and bassboost turned off. It was just like my mids/highs amp where the gain barely had to be turned up before it would clip.

Once that was all done i then went on to program my 3sixty.2 and in the next post here is how i did that....

[bkolfo4]

In one of my posts, I mentioned - don't forget to check for faulty equipment. A bad RCA cable, DC offset from the amp, etc. Anything like that can cause a lot of current to be sent through the sub coils while there is no cone movement. No movement, no cooling.

Keep in mind that your amp is well over the rated power of the sub. While other people are using a lot more than rated power, there are too many other variables to play the "other people are doing it" card.

Those are just a couple of ideas that assuming you set everything up 100% correctly could still be the reason you ended up with a fried, expensive subwoofer.

[kickass audio]

Ok so now here is how i setup my 3sixty.2...

1.) Unplugged all the rca's going from my 3sixty to the amps.

2.) Played the pink noise (or its white noise, idr the name of it, whatever the one is that comes with the 3sixty.2 when you purchase it lol) track on my radio.

3.) Went into file>new install>oem source

4.) Followed the on-screen prompts and waited like 10-15 mins for it to figure out the freq response of my headunit. Once that was done it knew where to set the eq curve to make a flat response for the outputs which is what i want to have. I dont want to have a crap ton of bass and no mids or highs. I want to have it equally distributed.

5.) Once that was done i proceeded to measure how far my speakers were from my head when sitting in my seat. Since i have the amp setup so that the front output on the 3sixty.2 is for just my mids and the rear output of the 3sixty.2 is intended for the tweeters i set it up like that. So i plugged the distance i measured into the 3sixty.2 program.

6.) Then i went to set the crossover settings on the 3sixty.2. For the mids (front left and right channel outputs) i set it to bandpass of 80-1500Hz with a 12db crossover slope. For the tweeters (rear left and right channel outputs) i set it to highpass of 1500Hz with a crossover slope of 24db. For the subwoofer i set the lowpass to 80Hz with a 12db slope, and for the infrasonic i set it to 28Hz with a 24db slope.

7.) I reconnected all the outputs of the 3sixty.2 to my amps and played some music. I noticed that my tweeters were super loud and sounded like they were going to blow right up. Since i couldnt turn the gain on the amp down any further and didnt want to play with the gain level on the side of my 3sixty.2 i went into the program and turned down the dbr setting for my tweeters until it sounded clear and didnt have any bit of a crackling sound to it. Then i noticed that my mids were somewhat over-powering my tweeters so i turned the dbr down from 0 to -5 and it sounded great for me there. I proceeded to my subwoofer which sounded just fine with the whole system at 0 but i decided to turn it to -3 so im not railing on the amps or sub with that much power.

8.) Since i figured the 3sixty.2 was doing all my crossover settings i left the crossover on the amps alone (stupid move on my part i believe as you will find out below)

I left the system like this for 5 months without any problems until one day the damn woofer sounded like it bottomed out or unloaded on itself. IDK what happened but it to me seems like the infrasonic filter on my 3sixty.2 just turned off for 3 seconds and then turned back on. I was listening to some young jeezy and we all know how low his songs go, well right when the bass note dropped it was great for a few hits and then out of nowhere all i hear is that SMD slamming to all hell and made the sound like the coil slammed into the bottom of the motor. Im not sure if it did or not but when i got home i noticed that my dustcap was laying on the floor by my batteries next to the box. It wasnt broken or anything but must have slammed into the pole piece of the woofer and made it pop right off. Well no problem for me, i grabbed some glue and put it back on and it worked like a champ for a few weeks until it happened again. Same thing low note played and where it normally filtered it out it went straight to the sub and it was wayy below my ports tuning level. So this time i figured it was the 3sixty.2 flaking out on me and i proceeded to ask Tony D'Amore on my facebook for assistance with how to get a decent setting on the amps crossover setting to help take over for my 3sixty.2 if it fails again. Heres what he advised i do:

1.) Turn off the x-over settings for the subwoofer on my 3sixty.2 just temporarily

2.) Play a test tone of where you would like to have the crossover/infrasonic filter at (i made a 28 and 80Hz test tone through audacity) and measure the voltage that your amp puts out on full pass with that tone playing.

3.) Take 3/4 of that voltage and that is the voltage you want to achieve when turning the infrasonic and lowpass on your amp.

4.) Once you have the 3/4 for your infrasonic and lowpass proceed to turn the x-over settings back on through the 3sixty.2

I did just that and it never bottomed out so i thought i was nice and happy with it. Well that lasted for awhile until two of the 4 tinsel leads on my SMD 18 broke clean in half. Now im at right where i am now, with no sub im my truck at all. lol. PLEASE HELP ME!!!

[kickass audio]

In one of my posts, I mentioned - don't forget to check for faulty equipment. A bad RCA cable, DC offset from the amp, etc. Anything like that can cause a lot of current to be sent through the sub coils while there is no cone movement. No movement, no cooling.

Keep in mind that your amp is well over the rated power of the sub. While other people are using a lot more than rated power, there are too many other variables to play the "other people are doing it" card.

Those are just a couple of ideas that assuming you set everything up 100% correctly could still be the reason you ended up with a fried, expensive subwoofer.

Can you please advise me how to check the dc offset?

As for the equipment i did put a old 750w rms sub on the amp for a few and it played just fine. I didnt go full volume with it because there no way in hell that sub would take that power. lol. I did have a faulty RCA cable for the amp when it was first installed where the connector would come loose and make the amps volume go up and down a lot. I found out that it was the rca and replaced it after the 2nd it happened. It never did that since. And i totally understand the "other people are doing it" stuff, im a firm believer in the whole tv speech of "dont try this at home" with my system and plenty of other peoples systems too. I noticed what you said with no movement no cooling and when i found out just how warm the sub gets when its not moving and sitting stationary i then would play the sub at 1/2 volume about 2 blocks away from my destination and slow back it down from there to give it some time to help cool off before i turned the truck completely off. Since i did that it never got warm to the touch so i figured it was good.

[kickass audio]

Also on a side note i just want to Thank everyone who did contribute to my previous thread to help me figure out what may have gone wrong. I apologize about how i acted right off the start but as Steve mentioned i was beyond pissed with breaking a nice sub like the SMD. Granted there were a few d-bags that just had to put their 2 cents in i am all calmed down now and am ready to learn how to fix any and all mistakes that i may have made with this system so that its perfected when it gets re-installed in 2 years. Again sorry about my piss-ass attitude i showed off the start and thank you for any relative help you can provide me and maybe other people who stumble upon this thread too.

[kickass audio]

lets bump this bish. help me out