altoncustomtech

I have the same HU and it has a fantastic set of controls with it's crossovers, eq, DTA etc. but it can be a bit overwhelming if you're not familiar with what all that does or how to use it. In the NORMAL mode it will run the crossovers in the most basic way they can be set. It will only allow high pass filtering for the front and rear speakers and low pass for the sub at 60hz, 90hz, and 120hz. MOST people run their components at around 90hz on the high pass filter, depending on the speakers and amp you may even be able to get by with 60hz. It's no big deal to turn them on and play with which frequencies give you the best sounding response as in your case in that mode it won't do much and you don't have to worry about hurting anything with it. When you turn on the filters it's going to reduce the amount of bass/midbass that plays through the Focal's, plain and simple. The frequency you set it to determines what frequency in the bass/midbass it starts to filter. Not much more to it than that, just keep in mind it's not a shelf or an instant reduction that NOTHING below that plays. It has a roll off, like a hill, and if you think of the frequency setting being at the top of the hill, the frequencies below that setting are gradually reduced in strength as you go farther down the hill. Hope that helps to make some sense of it.

Here's a quick rendering. Final specs after adding the double baffle is 2.99cuft NET tuned to 32hz with the same 47.25sqin of port area. I was able to get the double baffle in without really eating up any of the internal volume thanks to the extra volume that was in for the bracing. Onto the pics. So, at this point if you like it, I can finish the design and get you the cut sheets. Two quick questions: 1. Do you have a router with a roundover bit? I can show rounded edges on the enclosure, port, etc. 2. Do you know how you want to finish the enclosure? (Colors, carpet, vinyl, bedliner, etc.)

Awesome - thanks for working that up. I would like to have a double baffle on the face of the box, if possible, so that the sub can be flush mounted. Forgot to mention that in my previous post... As for the sub & port orientation, they'll need to be facing the rear of the car. It'd be great if the port was on one side of the box & the sub was mounted on the opposite side, but this is not necessary... center-mounting the sub would also be fine, if that's easier. Thanks again for the help, Alton. Much appreciated Alright, double baffle within the 20" it is. Placement on the box isn't really any kind of issue for me designing. I'll draw something up real quick and you can see if it's what you're after or not.

A few reasons I suppose. One is weight, not necessarily for the truck but for my benefit since I'm making it easy to remove so things don't get damaged when I haul stuff in the back. Another is curiosity, because I've never used it before and want to see what the differences are. It's supposed to be easier to work with as well which will be of benefit, or so I've read, which is one of the bigger reasons to me. I swear MDF has to be the hardest material, next to concrete, on blades. I may be picky, but it seems like blades just don't hold a great cutting edge with MDF for as long as they should. My saw goes from sliding through like butter to having to use more steady pressure than it should, and definitely more than it started to, take to cut it. Although that's also working with the blades that are available at the stores around here. Ordering higher quality blades might circumvent that, but they can get expensive fast and since I don't do this for a living it's hard to justify the cost.

I still don't understand the problem with this. As long as it's not being switched with any real power on it there shouldn't be an issue. I used to have a test rig for installing speakers/components/etc. that had six double pole/double throw and four double pole/single throw non-shorting switches mounted in a box with long pigtails in it that allowed me to connect it between the amp/speakers or crossover/speakers to do instant phase reversing on individual drivers from the drivers seat. Never had any issues doing that, though I did use high quality switches and would turn it down before making the switch anyway. Made an instant and easy way to test phase relationships in a car, I should really build another one now that I think about it.

I can take pictures of my trucks if you like, the Jimmy has the switches in the jam, and as I mentioned before the big truck doesn't.

You don't need to sit behind the car, back into the parking space. As far as the door chimes, look at the door jam and see if it has a switch there. A lot of newer cars put the switches in the door latch and all you have to do is take a screwdriver and push the latch back as if the door was shut and the lights/chimes stop. Then just pull the handle and it will pop the latch back open so the door can shut correctly. I do it all the time in my '07 Chevy 2500 work truck so that I can listen to the radio with the doors open while working on meters, transmitters, valves, etc. on our pipeline without the damn chime going on constantly. Just have to remember to pull the handle and open the latch back up before closing the door, that really sounds bad if you don't, lol. If it does have a switch in the door jamb, just find a simple little wood block or something to wedge in there and hold the switch in, voila same thing as above the chimes are defeated.

Under the hood, behind the grille tells me he's planning on using it to hear the movies outside of the vehicle or something like that. I don't understand the point past that though as if it were me I'd just disable the interior lights, back into the parking space and open the doors if I were going to sit outside the vehicle in lawn chairs or something like that to watch the movie. I'm also trying to understand why Nick is so against a switch to the speaker though. I mean, in a higher powered configuration it wouldn't be good to switch it with the volume turned up, but otherwise I don't see the issue.

I agree with rick, there's WAY more to it than them just adding the subs and not being happy with it. I would imagine they cut corners to fit the boxes in the vehicles and didn't have good box designs, coupled with a completely different alignment with the vehicles acoustics and they got bad results from poor planning. At least that's my guess on their comments, you're not going to go from awesome to horrible adding more of the exact same sub that was working awesome unless you just plain screwed something up, plain and simple. Now, You've definitely got some good room to work with. Were I in the same shoes as you, I wouldn't hesitate on another pair of DCON's and I do have plans for a quad DCON c-pillar wall build for a project vehicle at some point in the future, but that's me and wouldn't worry about a few other peoples mishaps and flaws.

Just for a quick run through the numbers, at 30" W x 15" H x 20" D I was able to get 3cuft NET tuned to 32 with 47.25sqin of port area at 3.5" x 13.5". That's a straight up simple L shaped slot port enclosure with a little bracing and no double baffle or anything. We'd have to play around with numbers a little more to get room for a double baffle, 45's, and that sort of stuff, no biggie. That should be a fairly well rounded enclosure. Do you have a preference on sub and port orientation?

I would like to add I've found a really great way to get the measurement for stripping the wire to a T. If you insert the wire before stripping it into the compression fitting to the point it stops, then either mark or begin stripping the wire right where the nut ends it will strip it to the perfect length every time for a perfect connection. I too love the compression fittings, although I know there seems to be a lot of people who don't, I have yet to have a problem with any of mine either. Nice video and it looks like a heck of a product.

I'm quite certain the 66mm xmax rating on the DD isn't just both directions, but the absolute mechanical limit in both directions. Everyone else measures the XMAX by the BL method so there's no way to compare the DD specs to anyone elses. I'm sure if you were to measure the Sundown's mechanical limits that it would meet or exceed that of the DD, but it doesn't matter because it's not really usable. Once the coil exceeds a certain point in the gap it's not doing any good anyway and distortion goes way up which is why everyone specs it with the 70% (IIRC) BL rating. I think all that's right, Quinten, Sean, and Brad would be much more knowledgeable in this area.

I agree completely.

to the forum!! You've made a fantastic choice on your sub and the RF amp should be a great match IMO. You're correct, D4 coils will be needed, wired in parallel, for a final 2 ohm load on the amp. As for the box specs, they're right HERE on the SSA site on the enclosure recommendations tab, but your thoughts of 2.5cuft NET tuned to 32hz is accurate and the sub should do very well with it. SSA's optimal recommendations are from 2.5cuft to 3cuft. Post up the dims and we can help you out with a basic design, no problem.

The filtering is typically done right at the high voltage rails with capacitors and rectification in an A/B amplifier and on the output stage in a class D IIRC. Class A/B doesn't typically present the problems with noise because its fairly easy and inexpensive to filter that signal at that point in the chain with caps and diodes or rectifiers. With class D almost all the filtering has to be done at the ouput stage because the high frequency (square wave I might add) has to go through the output fets thats modulated by the input signal. The inductors knock the edges off the digital part of the signal to make it a sine wave again. The problem there lies in the "cheap" part as high powered inductors that can filter everything as it should be are Not as cheap as caps and diodes/rectifiers. Class D amps work very very similar to a high frequency variable speed motor drive system (I think that's the right name). The difference is that instead if modulating the duty cycle with a constant variable and no need for any filtering an amplifier modulates the duty cycle with the input audio signal and filters the output for playback through a speaker. Now, I could very very well be off on a few of these details but I think I have remembered the just of it all correctly. For a person to make their own filter bank for a class D amp it would need to consist of a very high power handling inductor with the right millihenry value to not also filter the needed audio signal. Capacitors would also be useful as the entire filter is basically just a high powered LPF in the first place. I would never suggest anyone actually build this for use in any case by any stretch of the imagination. If you suspect a piece of equipment is malfunctioning you should have it inspected by a capable person. Or if you suspect one to be built cheap then don't buy it and save your money for something more reputable. In any case it takes more than JUST bad or cheap filtering to cause the failures as distortion, installation, program material etc. all play a part in the final signal the speaker sees. Get enough kinks in that chain and failure will be imminent, the same goes for ANYTHING audio related. To the OP, you said you had a local shop test the amp, what exactly did they do to test it? If all the did was hook it up and listen to it play they didn't really test it. At the minimum they would have needed to put an oscilloscope on it to verify there was absolutely no DC in the output and the high frequency the amps power supply switches at is WAY above anything audible (in most cases) and even if it were in the audible range you'd never hear it because the natural inductance of a subs coils would filter it down anyway and it may not even be a high enough level to be heard over the music signal. Test equipment would be the only way to know its there and just because you can't hear it doesn't mean it can't potentially do damage. Shizz, building a filter bank from a coil and caps would really only be useful for inquisitive testing purposes and ideally only with an amp that had known noise issues. I think the vast majority output clean enough signals that they never cause a problem. It's the rare odd case where all the wrong things happened at the wrong time for a long enough time frame to lead to this kind of failure.

The problem is that you're dealing with AC voltage, the rectifier is going to do it's job filtering no matter which direction the current is coming from (whether it's a half wave or full wave rectifier, it won't matter) so you're going to rectify the output from the amp as well. I know where you're going with the thought, but it's not applicable for this. Why not build a filter bank, such as the amps should have for starters. Also, the control of the back EMF in the amp is measured as it's damping. IIRC class D amps don't have near the damping A/B does due to the output coils that are in place to smooth out all the digital noise in the first place. I think its food for thought.

Vids look good and the box came out fantastic! Awesome score too, are you liking the sound of the XCON's as well as the output?

so subwoofer build error and amp build error is out of the question? companies make mistakes FI basically blames large korean amps sending microwaved signals but OP has a quality sundown..... if all but 1 had a coating then there's still no way for them to touch each other and short out OP even noticed something funny about the sub before the fire It has nothing to do with the sub itself, really. Even though his amp is a Sundown, it still operates on the exact same principles as any other amp. To add to what Nick said, what typically happens is that the high frequencies of the power supply that convert the vehicles 12v power to the +/- higher voltage for the amp to create it's output with doesn't get filtered like it should. Now whether it's by shotty design (cheap amps) or as the case may very well be here that something in the amp has failed, it's still the same cause. The OP may be able to test for it by connecting a DMM with frequency measurement and ACV to the output of the amp with no RCA's attached. If he sees a high frequency on the output and is able to measure anything above a minimal (< tenths of a volt) amount of AC voltage then he definitely has an issue with the amp. The best test would be with an O-scope, but not many people have those lying around. Fi sub or not, I think this would have happened and I'm sure it's related directly to a failure in the amp itself.

No, the amp has a lpf. Also aimone, he didn't specify what else he is going to have hooked up to it. I figured he planned on running the rest of his speakers with the HU's internal amp and in that case he can setup the outputs as subwoofer outs according to the specs on Alpines website. Otherwise, yeah, the sub amp has it's own LPF and therefore there would be no issue. As I mentioned before, I think the real issue is in why the OP is asking whether or not the HU will work with his equipment. Whether it's misinformation, misunderstanding or just plain still learning we need to know why he's asking the question to really help.

Why wouldn't it, or any HU for that matter? I'm curious why you're asking if "X" HU will or won't work with your amp and subs. Input to my curiosity would likely be more beneficial as I think your issue resides there and not in your choice of HU.

I'm answering based solely on the fact that I think you're fairly serious in asking and I don't think it would hurt to give a serious answer or two. Keep in mind that my answers are based solely on my limited experience and opinions so they may or may not amount to a hill of beans and may or may not conflict with fact or other member's personal views or preferences, and will not be anything but my most honest thoughts. Truconcept, on 20 Mar 2013 - 09:48, said:Hi guysThe last forum I was a member on misguided me terriblyPlease help me with some questions I have thanks! 1. can i use 2 ground wires for lower resistance?Sure, not sure why you think you need it.2. are 5/7 eq band head units pointless for a bass head since the eq shouldbe at 0 anyways?No. IDEALLY the EQ should be flat, but that would require a PERFECT speaker and installation which will NEVER happen, especially in car audio. An EQ can be adjusted up, but gains need to be readjusted when doing so and the proper way to adjust any EQ is to CUT or lower frequencies FIRST, then raise the ones that still need it (of which there will be few if any and almost no boost in most cases)3. why is a 4v headunit better than 2v?Technically, it's not. The only advantage a higher output voltage has over a lower one is the possibility of keeping induced and existing background noises at bay due to the level of the music signal being considerably higher than that of the noise signals, essentially like a higher SNR (signal to noise ratio). While that can be shown on an oscilloscope, it's audibility is pretty much a moot point with a quality installation and when quality equipment are in the signal chain.4. do you guys with multiple alternators have custom belts made?In the most extreme cases they might. Most auto parts stores carry an unreal variety in lengths. I find it hard to believe a "custom" made belt would really be any tougher than an off the shelf one.5. what specifically is in an expensive amp that a cheaper brand does nothave?Quality components, better board layout, better overall design. The quality of the capacitors, transistors, copper on the PCB, etc. all play a part in the total cost of a unit. Better R&D means more money spent to ensure a products quality and reliability. At least those used to be the main reasons for the difference, in today's market it's pretty much a wash. Another thing to remember is that it's not that the cheaper amps are horrible in the sense they are complete crap in the reliability realm, as most last as long as anything else when used properly. The biggest problem with them and the reason most people hate brands like PA, Boss, etc. is because they claim power ratings that the equipment couldn't output if they were hit by lightning.6. how can these guys patent a basket design? is it their reward forfinding the most effecient design first?While ANYTHING can technically be patented, when hours of hard work, design, etc. go into designing something AND it is truly unique then it can have it's own patent and IMHO the person/people who did all that hard work have every right to do so. It protects that hard work from being copied by others and profited from.7. why don't people use the 21" incriminator death penalty more oftenin builds?Space. A sub that big, the enclosure it requires, cost associated, etc. all play a part in it's usability. Not to mention that cones that large are subject to stress issues. While the enclosure size itself is about the same as alot of other popular 18" subs the real estate the sub takes up on the face can limit where and how it can be installed. It's typically much easier and more practical to use an 18".8. what is the difference between A class spl and C class spl?I can't offer a great deal of insight here without knowing the specific sanctioning body you're referring to. For that matter a little bit of reading on the information from that organization will likely answer your question. I think the difference is comparable to the different classes in AMA. 9. Car audio shows seem like a sausage fest, is there a lot of fighting anddrama?LOL From my limited experience attending shows, no. While it's no secret that the vast majority of car audio enthusiasts are indeed guys, there's plenty of girls to look at, lol. As far as the fighting and drama, people + alcohol = trouble. There are idiots at every gathering and while I'm sure it happens from time to time, of all the shows I've attended I've only seen one fight and it was because of an idiot grabbing another idiot's girl's ass. Subject for confrontation in most peoples opinions I think. 10. If I get metered and only score a 100, will some idiot be around 2 makefun of me?Probably. There are idiot's everywhere. You can in turn make fun of that idiot when he blows his shit up trying to beat your 100.11. Do a lot of cars get broken into at these events?In my experience, no. There's an awful lot of people around all the time at most events, I don't think it would be terribly easy to do. At the same time I'm sure it HAS happened before, I just wouldn't think it's a common occurrence.12. If I bring my girlfriend, do I have a better chance of guys giving me ademo?Yep, it's a requirement that showing tits is the only way to get a demo, LOL. Dude, the majority of people are there to show off their stuff. I can't imagine the chances change, much, with or without a girl by your side. Some people are strange tho and I can't speak for everyone.13. Are there any "unspoken" rules at a car audio show? (no touching, no pics without permission?)I think it's proper etiquette to ALWAYS ask before touching ANYTHING that belongs to someone else, it's just good manners. Pictures of the car itself probably aren't a problem, but I would ask permission before taking close pics of the equipment, install etc. just in case the owner is funny about it. 14. Do they sell beer at car audio shows?Depends on the venue I think.15. Do people often sell used amps/subs ect at these shows?Most of the time yes. What better place to sell something audio related than at a car audio show? I have been to a couple of shows that didn't allow that in the venue during the show, but those were a bit different.16. Is it ok to bring my innocent 11 year old cousin to a show or would iregret it?Almost all shows are definitely family oriented. There's always some girls walking around with some skimpy outfits on but I doubt anything he's not seen before and hopefully not anything he's not interested in seeing more of.17. what is the most popular subwoofer wire?Okay, this one doesn't make any sense. Speaker wire is speaker wire. 12AWG is sufficient and often overkill for pretty much every install and the vast majority of terminals can't fit anything larger than 8AWG.18. is loud bass on a boat something people do?I'm sure it's something that some people do, just like car audio, if one has an interest in it.

I've never used anything but my ears to set gains, unless I was gain matching amps, but that's an all together different scenario. Like 95Honda said, using a DMM to set the gains is arbitrary at best. Depending on the recording level of the tone as well, all those variables change every time you go to set the gain, and once you're playing music it's completely useless. The best thing to do is get out music that you're VERY familiar with, preferably a real recording not digital music. Turn up the volume to the highest listening level the rest of the speakers can handle without distortion and stress. Now turn up the gains slowly while listening for distortion and stress from the sub and smelling for any overheating. Do this carefully, listening closely and making adjustments as you go through a few songs. At this point it will be set pretty close and you have to remember the recording levels, bass levels and types all vary from song to song making it important to have your ear tuned in to what everything is doing at all times.

to the forum! I have to agree, that's a great lineup of plans for the car. I would highly suggest looking at SDS (Sound Deadener Showdown) sound deadener and reading the information on the site there. Don really knows his stuff and his products reflect the vast knowledge he possesses. Not that the Dynamat products aren't good, but his information and products will likely save you some $$$$ and the entire treatment is extremely effective. If you're limited on space the single 15 or pair of GCON 10's would kick some ass but you can get more cone area and potentially more output while keeping the great SQ the subs have to offer with a pair of the GCON 12's if you have the room for a proper enclosure. Whether it's a pair of 10's or 12's the KX1600 would be plenty of power and the 1200 for the single 15 is great. There's no need to get crazy with power to get awesome output from these subs. I'm real interested in hearing your thoughts on the QS65.2's too. I've considered pulling the trigger on a set for awhile now. Most importantly, be sure to post up pics in a build log!