Advanced Discussion

Okay, so i think i fucked something up in my 86 GMC S-15 that deals with electrical, go figure right.. Everything was working perfectly, then.. i connected my (2) D3100 XS Power batts with (2) runs of 0AWG wire (pos n neg) and something (idk what) happened and this is the results... I started my truck (got low voltage) and my Head Unit didn't turn on, along with amps. I put a test light on my 15amp Radio fuse in my fuse box by my kick panel and no power, so i pulled it and it wasn't blown but i replaced it anyway. Then put a test light on it and still no power. I pulled my Head Unit to check the factory 10amp fuse and i got the same issue, no power but not blown. On my f…

http://www.sciencedaily.com/releases/2007/06/070603225026.htm we can we expect to see these in amplifiers? and how much more efficient would they be if 30% or more of the heat was turned into electricity? what about lining sub boxes with piezoelectric crystals to make electiricity from the sound subwoofers produce. and have that electricity go back to the amplifier/capacitor.

I was reading a port area article on here. Port Area - SSA Car Audio Forum Utilizing the recommendations from other in that article and going back and looking at white papers from various manufacturers from the likes of JL, JBL, and Boston Acoustics etc,,, I notice that their port size recommendations are in the 3-4" area. Even on woofs that are known to be seeing 500+ watts. Why? After looking at those enclosure recommendations it is very apparent that the port noise is going to be horrendous let alone compression. Also utilizing the port area calculators in the above listed topic, I noticed that port resonance frequencies drop in frequency the larger the port diamete…

Bl/Mms is constantly turning up everywhere to describe the "acceleration factor" of a driver. This is totally wrong! The "acceleration factor" or "speed" of a driver is determined only by the bandwidth of the driver and nothing else. In reality the "fastest" driver or the one with the quickest rise time is one that can play the highest frequencies! Here we will use a picture to help explain the situation. In the following we show time from left to right, and amplitude from top to bottom. - Picture courtesy of Cool Edit 96 - www.syntrillium.com We have 3 complete sine wave cycles showing with a period of silence between each. The first one we shall say is 20hz, t…

Got my hands on a FLUKE TiR thermal imager for the day so I figured I do a little testing on the heating and cooling of my subs/amps. So Playing my system full blast for about 4 1/2 minutes (usher-daddys home off decaf's zip 14) The main frequencies peak at 39hz, 38hz, and 26hz. Subs just starting to get stinky(clipping a tad to see how hot I can get them) Subs are in a 17C.F C-pillar wall after displacement, tuned to roughly 28hz. Subs are (2)18" AA Mayhem D1, amps are (2)Colossus XXV clamped at 2,800 RMS each. First image was taken within seconds after turning down the volume to 0. Shows the center(dustcap area) of the sub being roughly 132 degrees, and just next to…

Ok before I get flamed I know I'm retarded for what I did to this amp.. Ok here is the deal I tried using another brand of bass knob so I had a clipping light.Well long story short it worked for about 5 seconds and blew the inline fuse. I tried reconnecting the AP knob and a new fuse it blew right away as soon as it powered up. Then same thing With no knob connected I checked inside the amp everything looks and smells ok did a few more test with a small fuses and used speaker wire as a jumper i can't get the power light to even come on for a secondbut the amp is turned on by the remote.. the top lights up just not the power or protect led's The amp is **** near new just w…

I need some help with the best way to hook up my subs. Right now I have one of my Punch P2D210 sub hooked to the B side and the + to the + and - to - like the manual said to do. Would I be better hooking the Sub1+ to the A+ and Sub1- to the B- ? With two subs Punch (P2D210 x 2) am I better off hooking Sub1 + to A+ and Sub1 - to A- / Sub2 + to B+ and Sub2 - to B- OR Amp A+ to Sub1 + / Sub1 - to Sub2 + / Sub2 - to Amp B- ? OR if none of these are are the best way then just let me know the best way. Thanks for the help. Picture of current single sub ( + and - are on B posts)

I'm thinking of purchasing a cheap broken amplifier off ebay just to try to learn to repair it. I'm a fairly fast learner and am good at learning new things, so it seems like it might be a fun challenge... What's exactly involved? I know I would need a test power supply (computer psu?), dmm, soldering kit... Is the basic technique to just look for components that are burnt or have failed and replace them?

Hey guys, I am having the following issue with my amp: The protection light comes on as soon as it powers up and it stays on. If I leave the amp on for a minute or so I can feel it getting really hot on the corner where the fuses are located on the bottom. The side of the amp is where it is getting hot and it looks like maybe a transistor over there (you can see if by looking in past the fuses). I have a Kicker amp that works just fine using the same power, ground, and remote wires. Memphis quoted $175 to fix it. I think it could be an easy fix if its just a bad transistor. I know how to solder and I've taken an amp out of its heatsink before to work on it but ended u…

Alright, so im working on a design for a new box for my NS 18. i am running a saz1500d on stock alternator and soon to be (hopefully) a new xs power battery(probably d5100) im gonna do it right at 5 cubes tuned to 35hz, so it will still be good for daily, and get me a little more spl for when i compete. so since i plan on competing as much as possible i was wondering how much port area to have. ik everybody says 12-16 but i was wondering if i should go more or less or just stick within that range. ik there are some people on here that are really smart when it comes to this subject so thanx in advance. also, is 35hz a good tuning for daily and a little bit of competing or …

i talked to a rep. at DC and he said i need 17inches of port area per cubic foot of airspace. how can i tell the port area of a round port? im going to be building 4, 4" in diameter ports, that will be tuned to 33HZ. the box is going to be 5cubes when its all done. i just dont know if i i will have enough port area to keep the port noise to a minimum. any help?

What aluminum alloy is best for electrical? Im asking because im using very thick and wide aluminum buss bars on my next build.

I have saved a little money for some wood, and still have glue, clamps and screws from my other box. I wanted to give building a T-line a try since i have heard fairly good things about them. It's just a for fun box, for my 12" visonik i got a while back. Amp and power and all that is covered, it's going in the house for now (no car til who knows when >.<). it's for music, primarily low notes in rap music. i was gonna try for a tuning of ~27-29hz. Now on to the hard part. I havent had alot of computer time recently, but in the time i have had, i couldnt find a calculator for a 1/4th wave transmission line. The specs i can give you for my sub: 250rms rated (takes dou…

pretty much my truck is telling me no to this system. I installed my box, wired my subs, wired the amp, fired it up... nothing amp comes on, zero output to subs. I do hear a whine through the door speakers if I rev the engine. -installed new RCA's -I have a 1/0 copper wire running to the frame as my ground. and after no sound I grinded the frame down to bare shiny metal. -checked all the fuses. -checked all the wires. -Rechecked all fuses and wires. -moved and jiggled the whole length of RCA -took the remote wire out and jumped a wire from the power to the rem When I turn the volume up on the HU as soon as a hard not comes through, the amp hits the subs once then goes int…

I need to know exactly what mechanical failure is to a sub woofer. I know this is a rookie question, but I need some technica answers as I think it's the reason for my sub's death. Or can a sub even break due to this. I am 110% sure it wasn't because of thermal failure. The voice coils look brand new when I took it apart. Yes I took it apart and ordered a recone before asking. I know part of it was due to playing freq. lower than box tuning and using bass boost. What part of the sub breaks or what does the coil look like when it dies mechanicaly + 1,000,000 other questions I have but i'll start w/these. Thank's.

I'm not sure if this is in the correct forum or not, because this isn't quite as technical as the other topics I searched through, but hopefully this one will do. I've got a friend from work who's son has an amp that is not working. I don't know a whole lot about amp repair, but I know how to check diodes, transistors, and simple stuff with a meter (no oscilloscope at my disposal unfortunately), so I am just taking a look at it for him. I dont have a whole lot of description about what the amp is doing, but from what he tells me, the amp will come on, won't go into protect or anything, but the subs will pop and them hum continuously. The first thing that came to my mind i…

Hey all, I've built plenty of enclosures and done 1 wall that I was able to build outside and slide in through the hatch but my next build I need to go as large as possible so build inside, and thats quite a change from slapping screws in, flip the box, drop more in. Can I get some links to build logs that have good pics of this please... I have been searching and found almost none that really help. Thanks! Krypto

I'm looking into buying a 15" BTL fully loaded. My question is, can I tune my box lower than the recommended fs frequency? If I did, would it affect the sub in a bad way? Poor sound quality? Just wondering if there would be a negative effect on the sub. I think the fs frequency on the 15" BTL is 37.9. I like low frequency hip hop and want to tune my box low like 30 hz (at the lowest 25 hz). Is this not a good idea, what would be the result?

hey whats up, I am learning about enclosure design and tuning and was wondering about two terms "imp rise" and "unloading". I breezed through a thread on imp rise and got some very good information. Its the unloading part that im not to clear on. I have a 15" Fi BL Loaded and think that I have damaged it due to unloading (I think). My question is how does it affect the subwoofer, what kind of damage can this do, can a recone kit fix the sub if broken due to unloading. I was having problems where my sub would cut out then cut back in for some reason as I was playing low frequencies. The amp was not clipping or going into protect as I could see all the LED's while this…

someone should do this with a voice coil and make the sub-woofer super efficient!!!

Hi guys, i am writing a paper about the behavior of woofers tied in with resonance, tuning and such, the behavior of a woofer under stress (i.e. during use) and a detailed diagram of all the parts of the average woofer. i am focusing on these main topics: A) resonance/tuning 1) movement at and around the tuning frequency 2) the uses and benefits of diferent tunings, uses; musical and competitions B) Behavior under stress 1) impedance rise 2) thermal compression 3) box rise + the effect of tuning on it C) mechanical parts 1) Moving parts 2) suspension/soft parts, and effects of different styles of suspension materials 3) cooling technologies Thanks for taking the time to r…

So, what is the cause of "moving air"? There are two possibilities in my mind that I think would create this. #1. Air Displacement from the motion of the moving cone of the subwoofer. #2. Actual pressure (sound waves) moving the air inside of the car. In scenario #1 the key to moving the most air would be to have the most cone area, the most excursion of the subwoofers and to have a sealed box (ports have an opening in them so technically a port would help the equalization of air pressure inside of the car) This would also explain why Randy Kubek pretty much has a mobile wind tunnel because he has always ran sealed boxes. ( for reference) In scenario#2, there is much …

I have not put to much though into this but I was just wondering if this would be a great charging system for car audio. The way a hybrid vehicle works is it runs off battery power at low speeds and at idle. The only way gas is used is when the voltage drops past a certain level to charge the batteries. This would be ideal for competition use as the charging system is geared toward the idle to low rpm range. There are multiple batteries in a hybrid setup and I am sure that the charging system would have to be pretty beefed up to charge a hybrid vehicle. A regulator could be used to change the voltage at which the charging system kicks in. If you were to have a high power…

First off I have two alpine pdx 600.1amps each amp is producing over 700 watts I want to buy 2 fi ssd 12s run 1 off each amp anyway here's the questions when ordering I'm asked about flatwind coil yes or no copper coil yes or no and bo power. Could someone explain this to me and what I should do to answer these questions thanks

I have a f150 std cab and im about to do a blow threw .. i only have room top to bottom for 12's but if i ever wanted to go bigger i have a idea how i could make it work. I just have not seen many people or any one ever build a box like this. Now t-lines work off of 1/4 wave and a 6th order is like a ported box with ports on both sides of the sub.. what would happin if i built a box and made it were there was port on the front and back of the sub like a 6th order but the ports were all 1/4 wave like a t-line just front and back.... the box would be huge because of the simple fact that each port would be around 9 feet long lol but hey i got a long bed truck so it dont m…