opinions from the masses, spl on a budget

Ok so I should have probably done this first, so I'll make it short and sweet. I drive a 1991 Ford Escort GT, hatchback, and the setup I have currently is a MA12D4 wired bridged to a RF P8004, sounds ok, but I'm smelling a bit of voice coil after bumping hard for about 20 minutes or so. I listen to mostly dubstep, and that itself is rough on subs because of the constant bass. What would be a more efficient setup that I could sell mine to replace with? I am big on SPL, I used to love SQ, but now I'm looking to see how far away I can be and still feel the music. Sorry to have so many useless posts, but I only get a chance to post in my offtime which is rare/never. Keep in mind the escort is ALL open space, being a hatchback and all, and it's hard to really come up with much that is functional for what I'm wanting. I'm looking to get as loud as I can without needing: upgraded alt (even though that's in the works as we speak), May contemplate a deep-cycle battery if the suggestion is good enough, and I'm working on a moderately strict budget (other than what I make cycling through audio equipment). Give me a couple suggestions and an estimate of how much it should cost, and I'll tell you whether its feasible or not. I'm not wanting to shatter glass, but when I pull up next to that punk kid who thinks his sony Xplod setup is so grand, I want to make HIM feel it. Looking for: at least 800rms, accepting more gladly! I also only want to utilize one single 12, DVC as usual, and a class D amp. Also something that is functional with at MAX a 2 cu ft box, including sub/port. Thanks much everyone!DJ Jack Ripper, Car audio noob (sort of)

At least the 91 Escort has a charge lamp so you can use an ordinary relay as a battery isolator... (no need for voltage sensing isolators). (Search my posts for UIBI; also at mp3car.com) If you get an second battery (AGM), it should be next to the amp. But keep in mind that a deep cycle will not handle high current as well as a cranking battery. But your battery choice depends on your driving profile - ie, the alternator's ability to supply the required voltage (current), and how much reserve time you require when it isn't (ie, the amp's run time on the battery). The alternator should be selected with the above in mind as well (obviously!).

Well although it probably eats up a bit more fuel, I have my idle set a bit higher at around 1000-1200rpm, so that it continuously charges the battery. A cranking batt is more what I'm looking for? Interesting. What all would be needed if you were going to build a 1000-1200W Rms setup? 800 rms is the LEAST I'd do, but that depends on the sub/box/amp setup, as far as acoustics go, and how much the aforementioned 3 could put out and how loud I could get it without having to recone anything. Looking for something I can rebuild if need be, I know the repairable subs are a bit more expensive, but shoot me some ideas. Thanks Oldspark for the tips, I'm putting everything I learn into a folder and going to reference it when I am ever in doubt. Scary part is I was being serious :) I have a folder with 3-400 items JUST on escorts. Little tidbits here and there. I plan to make it a PDF someday and give it to my fellow scorters who ever have questions about the small stuff nobody takes notes about. Can you give me a brief synapse of what a chargelamp does? I'll go more in depth when I have more time on my hands. Thanks!DJ Jack Ripper, Car audio noob (sort of)

3-400 items... LOL! Yeah - I have non-too-common vehicles from the 1960s & 70s, even a rarish 1986 (Piazza/Impulse). Let's see - my Isuzu folder has... thinking... counting... 11.5Gbytes under it. (That doesn't include /forums nor /batteries...) And one day I might continue my conversion of paper notes to soft documents... Yeah, one day and a half! Now, audio... Oh crap - where do I start? Firstly - upping idle speed... naughty naughty green house gases (I have to write you the Riot Act), but I am obviously dealing with someone smart enough to know to do that to ensure charging. (IOW - yeah man, I respect you already - so that makes two naughty boys!) Though you may not always have to charge above eg 13V etc - the charging/driving profile may be enough to recharge the battery. But then there is whatever voltage you need/desire for the amp output, but more ion that below... Audio - I read so much crap about powering audio systems, especially on audio forums. But not all or not always - some IMHO have the right info. (And the "experienced" people I meet seem to know the same...) But f.ex - those that reckon get a bigger (or more) battery(s) INSTEAD of up-sizing the alternator... If the alternator isn't replacing lost charge, more battery merely extends reserve time. How will that be recharged? A wall outlet, or driving without LOUD for a while? And if a higher voltage means a higher output power, then ytf would they want to run on batteries (12.6V and lower) instead of the alternator at say 14.4V? If voltage means power, then the power at 14.4V compared to 12.6V is 30% higher! [ IE - (14.4/12.6)**2 = 1.30. That's from P = V**2/R where "**2" aka "^2" means squared; ie, V^2 = V**2 = V*V or VV (V times V) - InOtherWords Power is proportional to VV. ] [PS - sorry for the math! But that's FYI, DIY, etc...] But IMO there is one typical contradiction.... If it's a high power amplifier, then it must be using an SMPS. IE - a Switched Mode Power Supply to convert to a higher voltage.    [ For a 12V system, "high power" means an output greater than about 200W into 1 Ohm. That again is from P = VV/R, eg: (14.4V x 14.4V / 1 Ohm) = 207W being the max power possible into 1 Ohm at 14.4V with 100% efficiency. ] 1200W into 1 Ohm means VV = 1200W/1 = 1200, hence V = 1200^(0.5) aka v1200 (the square-root of 1200) = 34.6 = 35V. (Sanity check: VV/R = P = 35V x 35V / 1Ohm = 1225W.) So, for 1200W into 1Ohm, you need at least a 35V supply. You don't get 35V from a 12V system without SMPS. (At least, not practically for high currents...) But SMPS can typically have a range of input voltage, bit not the output. That 1200W output should be fixed at (say) 35V. It might be 36V or 38V in practice to allow for output transistor or FET voltage drops, but it should be a fixed or constant set voltage. [ That might be a bit technical, but in my experience, SMPS are fixed outputs. EG: dc-dc converters (as used in amplifiers) might have an 8VDC to 16VDC input range but will provide a fixed 12V or 19V etc for laptops etc. Same with AC inputs - a shaver or PC SMPS may take 110VAC to 260VAC but provide fixed 5VDC & 12VDC etc outputs. ] Anyhow, that SMPS versus "linear" behavior contradiction is one for the audio or amp buffs to figure out, or explain to me if they have a rational answer. (Sorry, but don't use max current input unless you can explain the varying output! I've killed that one before too.) I see many amps that claim higher output power with increasing voltage. In fact, they seem to be totally resistive - ie, from P~VV, Power at 18V compared to 16V will be (18x18/(16x16)) = 1.265625 = (26.5625 = ) 27% higher. In that case, although IMO they are not simply an SMPS, they then do want a higher input voltage. So ytf to so many advise more battery rather than an bigger alternator? Have they already reached their 250A or 350A alternator limit and can't add any more? Or why not use 7-cell batteries? (Ok, so some comps ban them...) Then there is the strange contradiction where caps REDUCE peak SPL, yet they advise AGM batteries near the amps. Why AGM? Because they have lower ESR than flooded cells. Why use caps - because they too have low ESR. So why not use flooded cells near the amp if you want higher peak SPL? (Sure - must be in a sealed vented enclosure.) Oh yeah - I forgot - lower ESR means "faster" supply of current.... Everyone knows that higher resistance slows down electricity... (NOT!) And apparently low ESR is so important, yet they swap their cranking battery for an expensive low ESR type, and then have 3m (10') of 4G to the amp which has almost as much resistance as the AGMs internal resistance (~ESR). Add the ground resistance to that.... (And many claim that chassis/body resistance is higher than a fat cable...) Furthermore, many reckon an AGM cranking battery will not last as long as an equivalent flooded battery (for daily use etc, and somewhat dependent on what "equivalence" means), so why not keep the original flooded cranking battery? If adding an AGM, then for Pete's sake, ADD it - and as near the amp or target as possible; don't substitute the distant standard (or flooded) cranking battery. Then there is this deep-cycle versus cranking situation. Deep cycle usually means a slow but DEEP discharge - as with camping, solar etc. Sure, they might be able to supply high currents, but it stresses their lesser plate area. Crankers however have thinner but more plates, hence a larger surface area able to supply higher currents. But thinner plates do not like DEEP discharge. Their application can be interchanged, but at the expense of life. Of course, there are those that are suited to both deep cycle and cranking - they have more AND thicker plates - and are still the same size and weight as dedicated deeps & cranks of the same rating. (IOW - yeah, right. IMO they are a compromise, else a deep cycle that is big enough to supply a high current which is enough for "cranking".) Maybe audio buffs use deep cycle because they want maximum time on one battery without charging. Personally I'd probably rather 2 crankers that can supply high current with less stress, and then provide similar reserve time - and tolerate a much higher recharge rate. But in terms of current stress, maybe 2 deep cycles instead overcome that issue... So may POVs. So many arguments. IMO so many contradictions UNLESS they are talking about specific circumstances. Some obviously have no concern for battery life (ie, cost); others do and spend more up front but less over time. Are batteries like people's backs? It's the straw that breaks them... you may have lifted engine blocks for years, then you lift a drink bottle and BANG! If two lifted those blocks, you'd still be drinking....? I know the above may not be helpful, but it may indicate why IMO people need to think about what it is they want, and then specify that to us (or just me?). LOL - I think of another the12volt poster wanting a 4kW design, then claiming success with much cheaper standby AGMs (ie - not for cyclic use) before he has even used them - and even then, no where near a 4kW system! And he was so worried about the right wall charger, yet expected to only need to charge them ONCE a month (not once per use or cycle!) - ytf would he need a charger.... equalisation; for AGMs? But I hear the sun in Florida is pretty strong these days.... And BTW - I'm not having a go at you. Like I said, you have already demonstrated an understanding for the need for a charging alternator. Did I mention bigger batteries instead of an alternator...? Yep - there I go venting again. Now, the easy part - the charge light. Maybe look at oldspark battery bank w/possible solar (2nd page) about 7th reply down where I link to the same diagram in 3 different the12volt threads. I've been meaning to combine & update UIBI and related charge-light threads for ages - there are bits everywhere including at mp3car.com. And I have lost track of where the latest diagrams etc are - I suspect now they are in emails unless I am thinking of some off-air ones (not on public forums). I thought I had much newer stuff here on the12volt. That oldspark battery bank w/possible solar thread has lots of my ramble with my last (on page 3) linking to Car and Deep Cycle Battery Frequently Asked Questions (FAQ) 2011 (English Version) - especially the Battery.Zip download - that's a great battery resource. It should be consistent with what I wrote above, but some stuff (like NOT keeping batteries paralleled) is beyond BatteryFAQs scope, though it is referred to albeit implicitly, or through links elsewhere. Ah yes, another short reply....

Wow. Interesting, I'm gonna have to do a bit more research into this. Any suggestions for a cost efficient setup that produces up to 120-140dB. I would only get a battery if completely necessary. What brands should I avoid? I believe my MA is fried, but it wasn't in great condition to start with. I have tried Cadence and was impressed with the CVLW122. I'm trying to keep it simple, one 12, one amp and just simplicity that can make at least a 120dB. Thanks a bunch sir!DJ Jack Ripper, Car audio noob (sort of)

you should be able to make a decent setup with about 1000 watts. you shouldnt need a new alternator but the big three is always a good idea. the thing that will make or break your system is always going to be your box design. you can make a single 12 hit hard with 300 watts with the right box. and just the opposite, if you dont have a good box design then you could get terrible results no matter how much power you throw at your woofer.you have a hatchback so it shoudnt be too hard to make something sound nice.

Well if I do need a higher output alt, I can get that done. It's gonna cost a bit because my Ford has a Mazda engine (1.8L GT), and a mitsubishi alt. Go figure. Anyways... Another question I had that is probably going to warrant a facepalm... Inline fuse is 60A, my amp has 3 40A in the amp itself. I keep blowing the 60A under the hood, and I'm not really sure what size I should get to be safe (and to stop spending 3.50 every 2 days). 100A? 150A? The MA is pretty much done for, it's making a rattling noise and it's got friction when you press gently in on the cone, so I'm guessing that one is fried. What I would like, is something I can bridge each voice coil to each channel, run a Y splitter from the RCA's to the front and rear channel inputs on the amp, and do it that way. Is that advisable or am I mixing up a whole mess of isht that I shouldn't be messing with?DJ Jack Ripper, Car audio noob (sort of)

the 100 amp fuse should be good. you blow the fuse every week because the amp is trying to pull more than 60 amps of current but it isnt a dead short so the fuse wont blow immediately. instead it just goes through heat cycles and it gets weaker every time you crank your system up. but realistically you could use any fuse rated higher than the total rating of the fuses in all of your amps in the system.. the main fuse under the hood is really just to protect the power wire and your car from catching on fire if it gets shorted out somewhere along the line. so instead of your wire getting hot and melting and catching your car on fire, the fuse blows and stops the current flow. why would you WANT to run each voice coil to a different channel? there is nothing really wrong with it but that really is just a rig method people use when they have a badly mismatched sub and amp. just get a mono amp and make sure it will be stable at whatever ohm load you plan you wire your sub to.

Ok well the amp I have is a 4ch rf P8004, and it's not bad per se but what I'm wanting is something simpler like a mono or a 2ch. I paid 150 for the rf and part of me feels ripped off... Either way, it'll work until I can get what I want and I can transfer the rockford into my project car. Anyone remember me griping about the MA? Well, I've accomplished something today I never thought possible... I fused the voicecoils.... It won't flex in or out, it's now a 23lbs paper weight. Anyone got any sub suggestions for me? Something illobly have to buy once, preferably available with a recone kit? I'm looking for 'make you sick' spl. I know I won't get up to steve meades level, but I want something worth the money I'd shell out for it. What would work well with the amp I have? Thanks guys!DJ Jack Ripper, Car audio noob (sort of)

Bit of an update... I still have the RF amp, but I acquired a Sundown Audio Nightshade V1 12" driver. From talking to the guys at sundown, they have told me a bit about the sub and just from the specs they've told me, it's a pretty impressive sub for the 150 I paid for it. It was taking the 800 watts from the RF amp until it blew the underhood 60A clear apart. Oh well... I need a larger capacity fuse underhood, and from what I've read, the AGC fuses only go up to 80A. Hmm... I never posted the above... Got the large style blade-type fuses. 100A in it currently. Woot.DJ Jack Ripper, Car audio noob (sort of)