Jump to content

ds1919

Members
  • Posts

    191
  • Joined

  • Last visited

About ds1919

  • Birthday 03/16/1965

Profile Information

  • Gender
    Male
  • Location
    Nevada City CA
  • Interests
    Family,Audio,VWs,Gold Mining,Ungs,Soccer

ds1919's Achievements

Newbie

Newbie (1/14)

17

Reputation

  1. well I think becaue of today's larger more powerful amps are so demanding on our alternators - be it stock or custom, we find we need some sort of "backup" power supply to compensate for when the alternator is unable to supply the power needed. This is where caps and batteries can come in handy, provided their contribution, is just that - a contribution, not a burden to the system, both electrical and stereo. Granted, the battery holds more power than a cap, but at lower resting voltage. Caps hold a higher voltage, but less storage capacity. Which one is better? Which one is useless? Which one works in which scenario the best, or at all? Audioanonymous - that setup would be great to run some tests with. Like perhaps using straight bass tones and/or sinewaves, and timing how long the caps work, spl meter, etc etc. Then if you have batts, could do the same there.....That system looks like it could be great for a controlled test (same conditions throughout the testing).
  2. Yes, there is proving it on paper, and also proving it in reality. Now, having 3 kids and no time, I cant do much for another 9 years when my youngest (hopefully) moves out! It would be great if some fellow SMD'ers could take on some "controlled" research/experiments. If you dont understand the term "controlled", then, well, your findings may not be accurate enough to make a solid conclusion. Nevertheless, I/we would still be interensted in you projects. Lets get some testing going!!!
  3. Naw not yet, just a lot of my own incoherent ramblings and perceptions and misunderstandings lol. I think I added like 5 comments yesterday. But no, he hasnt chimed in yet, and I'm all caught up with the thread. have you read the Glass Wolf article yet? its pretty good stuff! And they didnt even go into Mohs, Siemens, voltage vs current traveling directions, or anything related to physics.
  4. but I thought the alt didnt have to keep the batt at 14v. Once the batt charge voltage is reached, doesnt the batt stop requiring the charge? Or does the alt constantly force the 14v thru the batt, which in turn acts like a resistor due to its own ESR?
  5. yeah I hear what you're saying, that the battery will not hold anything more than its floating/fully charged voltage. And I understand your statement about batteries can only produce so much power, but I dont fully understand how that is so. Do you mean that a car battery will produce, on its own, up to say, 11.5 volts? And after that the alternator must charge it to its floating voltage? And another question, how is it so that the battery is a constant drain to the alternator? I understand and agree that the alternator voltage is around 14v, and the battery is around 12.5v (give or take a few on each). But once the battery has been fully charged by the alt, and is resting at its floating voltage, doesnt the battery then become "passive", and will not do or need anything until the total system voltage drops below the battery floating voltage? This is one of the things on the Glass Wolf article that I dont understand.
  6. wow just finished reading the entire Glass Wolf article. Its a must read for all on here if you havent yet. Now I think I'm getting a clue as to what was going on with my electrical/charging and audio system. I had a thought of getting a large high value cap for my redo, but I think now I'm not going to. I have a feeling it was not only doing nothing for my system, but was dropping voltage. Hmmm
  7. According to that Glass Wolf article with the link mentioned above, Richard Clark mentions "There is a very important concept to understand about energy storage. A capacitor actually stores electricity. Batteries don’t. Batteries have the potential to produce electricity by means of a chemical reaction
  8. are you sure? Doesnt the sulfuric acid and lead, thru ionic chemical process make power?
  9. oh forgot to add that my systems never really required 260a of power. Mostly they prolly needed about 180amps, so the alt, I believe, should have only needed to supply about 180-200amps. This is where I would scratch my head, wondering why my lights would dimm on heavy bass peaks. It made me wonder if the caps were sucking power etc....
  10. this has been an interesting topic for me for prolly the last 10-15 years. Since 1999 I guess. I've always wondered how much they contributed to the power supply of a system. In my own relatively modest car systems, I did notice a difference in the tightness of the bass when I used a cap. But that was when I had 300-500Wrms amps and that was it. Later on I started using class D mono amps at 1500-2000Wrms. At the same time I upgraded my alt to a 260a DC Power alt with upgraded reg, dual strands of Knu 00 for the Big 3, etc etc. Even with this "El Primo" electrical wiring (everything done correctly etc), and with a couple caps near the sub amps, I still experienced dimming. It made me wonder if the caps wee of any use anymore, now that the current demand of the larger amps possibly far exceeded the usefulness of the caps. Last week I ripped out my system (amps and subs and caps), and am in the process of redoing it. I will be leaving out the caps for good, and installing (in the rear) two Kinetic HC2000 batts with 102Ah each. 0ga wire to connect to each other and to the power wiring. I am interested to see if my old caps were causing a bottleneck, or constantly draining and charging thus causing strain on the system. It makes me wonder if caps, to be of any use in a car audio system, must be the focus of the design. In other words, you gotta build your system around the caps' capacity, otherwise they will not work correctly and will be a burden to the system. Unlike batteries, which are possibly or most likely a 100% added benefit to ANY system of ANY size.... One thing I have not read on this thread (yeah Im all caught up on this topic now lol) is that batteries make power, and caps store and release it. Thats a big difference, especially since car audio systems are constantly demanding and then not. So batteries seem to be less burdensome than caps because they can make their own power, causing less strain to the alternator, whereas caps are constantly recharging, causing some factor of strain/draw to the electrical system/alternator.... I dunno if any of this is accurate or not. Im glad this topic is being discussed in full detail, I cant stand those one line posts like "caps are crap dont get them".... I need to know why, if so....or if they're possibly beneficial in some circumstances/configurations. btw. my front batt is a red top Optima. I'd rather use an XS or Kinetic, but I cant find one that will fit (jeep takes a small and low batt and the kinetics are too tall and hit the hood. My HC1200 is too tall).
  11. hey daily! where you located? Lol I remember the mini truck dayz, I had a chevy luv dumped 5 1/2", could scrape mcdonalds litter down the street lol. That was when I lived in the east bay, san ramon, now I guess kinda expensive. hey send me the model of that 15" eclipse, I can see what size box/port works best. Right now I'm running four of the Sundown SA8v.2 D2s. I just took out my custom set of 15s. I might put them back in to see how they sound with my new amp once I install it (Ampire 2kWrms class A/B).
  12. My box is 2 cu ft for four SA8v.2 D2 subs. thats the internal box volume. I also have a slot port, dimensions are 9.5" x 3" x 22". Its all the room I had left in the trunk to get the port to work. My tuning is around 36hz. A 1.0 cu ft box for all 4 subs wont sound good. For a temporary sub system, before I finished my box, I had two Skar vvx8 subs in a tiny box, about .3cu ft per sub. They sounded horrible in there, and the subs didnt look healthy at larger volumes. Specs are similar for both brands, and so they do need a minimum of .5 per sub. Figure .1 cf for the displacement of the magnet and stuffing, so you want internal box dimensions to be a minimum of .6-.7cf. And ported is a must, they love ported. Sealed doesnt sound good. You may want to look into perhaps building a setup with two 8s and one or two 12s. You;ll get the snap from the 8s as well as some lows, and also some truly deep lows with the 12. that has always been my favority setup, and I may switch to that.
  13. Damian here, livin in the gold bearing foothills just east of Steve. Been a bass head since 1984. Yeah, almost 50 years old and I just cant stay away from this shit! My kids are almost deaf but thats okay lol....
  14. lol. Before I built my box for my SA's, I put two in like a .5cf ported box. Thats like .25cf per sub. Sounded like shit. why? cause the design of the sub is Fs at low 40hz. Box tuning was like at 90hz. Couldnt handle hardly any power before they started flopping and popping. You wanna build a box that works with the woofer, and port tuned (if you want ported) properly. The smallest a v.2 should be in is a .5cf, and the largest is .75. You could go larger, and the box tuning will be deeper, but you may not get a needed spike in the low end, just a smooth deep rolloff with no punch. If you're board of stereo stuff, speaker repair should be fun. I've done a few in the past years ago, not lately, too impatient. But if you get real good at it, there is a job for you anywhere! There aint enough good speaker repair people anymore
  15. enclosure design and tuning also depends on how the manufacturer designed the sub. Some design them for sq, some for spl. So their box recommendations reflect their design goals. I just finished (today) building a box for two SA-8v.2 D2's. I already had a nice well built box at 1.828125cf. Then I added in the 0.08 for sub displacement, 0.0625 for internal matting, 0.015 for wiring, and another 0.03125 for stuffing. That gave me a net volume of 0.7253125ft3 per sub. As jacob stated earlier, the larger the box, the longer the port length. For a 3" diam, I needed like 17", which I didnt have. So I had to go with a 1.55" diameter at 4.5" long. Its the correct tuning, but possibly restrictive due to the smaller diameter. However, upon listening to the setup, it sounds fricken awsome! I'm ditching my dual DVC 15" subs for these. More musical, goes just about as deep, doesnt take up as much space, super tight bass. I like them a lot. I'll be designing another box for 4 of these SA-8's. Oh yeah back to the subject. For these subs, it seems like Sundown's box recommendations are spot on for sq and spl. There's a whole lot of electrical (capacitance, inductance, frequency impedance, etc) and mechanical criteria that changes with box size and tuning (port lenght/diam). They've already figured it out, and I can say it does sound great.
×
×
  • Create New...