Huh?

Discussion in 'New Member Introductions' started by PolkMM, Dec 13, 2003.

  1. PolkMM

    PolkMM Full Member

    Hey all,
    Well, first, let me introduce myself. I’m Cody, I have no records, never competed in any type of audio competition, and own no company…lol. If you haven’t guessed by the screen name, I run polk. Probably the only one in this forum that runs polk…But I love it just the same. I came to this forum seeking knowledge. I’m a regular on the polk forum, but we don’t have the resources like this forum does to provide the type of information I’m looking for. But anyway, what I got when I came here was far more than what I expected. I was looking at the post "the beast" when it started, now called "george." When I saw the first post, I thought I was really going to like this topic. I knew it would be full of information from a bunch of guys that really know their shit. 7 posts later, I was completely lost. I looked in topic "Important: Tutorials... No Need To Ask, They Are Here," maybe I missed it, but I did not really find what I was looking for. What I am looking for, is, online tutorials that can even get me, possibly the most "audio ignorant" on this forum, up to par with what all these letters mean(in REALLY good detail…lol), how they affect the driver, and what does that mean in terms of what I hear. Letters as in Vas, Qes, EBP, IMD IIRC, T/S, Vb, Qtc, Qts, well, you get the point. Some of these I may have heard of before, or know what they are, just don’t realize it, but the majority I’m sure I don’t know. By looking at some of these posts, I also find out that my crossover points are much different than some of yours. Me being the newbie (I’ve had about 2 years of car audio experience, I’ve heard a lot of in car set ups, but I’ve never heard an ED sub or an Adire sub in my life, I’ve always wanted to listen to the Brahma, because I’ve heard so many great things about it, but never got the chance to, also, any experience of mine does not come close to the depth you guys go into) and you guys being the people who know a lot more than I do about this, I could definitely use some help. If you look at my signature, you can see what I’m running. Its all in a full size extended cab truck. The subs are in a dual chambered sealed box with an airspace of .88in^3 per chamber. My crossover points are 100Hz for the MM6s, 80Hz for the 4x6s, and 80Hz for the subs. I’ve read some of you have your mids crossed over as low as the low 60s. The reason I have my mm6s crossed over at 100, is pretty much so I can turn the gain up, and they won’t distort at higher volume. I’m running 225watts to each crossover, they’re rated at 125watts I believe(and trying to build boxes for these in my doors is just more work than I want to do.) My sound stage is a little in front of me. I’m missing some frequencies b/t 80 and 100, but I hope to end that by amping the 4x6s and trying to pull the sound stage back so it’ll be right on top of me(which is where I want it.) But could someone explain to me why you have your mids crossed over so low? Do some of you run 3 ways and that’s why or what? Also, if you want to take a look at what I’m running, here’s a link to a post I made click here, just scroll down, and there’s 4 links to pictures of what it used to look like, as it has changed a little since the pictures were taken. But if someone could help me find a link to some good sites to explain some of the stuff listed above to me, or even a link to a topic made a long time ago(on this forum or another) that discusses this, I’d appreciate it.
    -Cody
     
  2. geolemon

    geolemon Full Member

    I've got a great thread for you to read...
    Let me introduce you to my "home" forum (although I've honestly been enjoying this place much more, lately B) ):
    CAF thread on T/S parameters

    The article posted by Polecat (who happens to be a top Kicker guy) is a really good one. Should answer most of your questions.

    I'm also pretty good with the specs, if there's any remaining questions after checking that one out, but it's a reasonably complete document. I'd be glad to take a stab at any questions after you check that out!

    Also, check out my links page:
    My links page
    There's some interesting stuff on there that I think would appeal to you, and some links to good references.
    I'm in the midst of redesigning my whole site, updating my list of links... it's going to include that thread that Tracy (polecat) posted, and a few other doozies I've got bookmarked. B)

    ...interestingly, I don't have Basic Car Audio and Electronics (formerly the famous Eatel.net site) linked on my page... be sure to check that one out too, for a nearly exhaustive encyclopedia style site on car audio. Very nice site. I note though that they have just changed their domain name.

    Anyway, that should give you a bit to check out... hopefully not too much!
    Regard them as reference sites, things to reference when you have specific questions. Good resources. :gunsmilie:
     
  3. geolemon

    geolemon Full Member

    Your Xover points seem quite normal.
    80hz is simply the normal standard for a subwoofer crossover. Couldn't be an more normal.
    So, you'd expect that you'd run your full-range speakers at least down to 80hz. You aren't far off.
    You generally do want your front speakers to cover as much of the frequency spectrum as possible, because that's what establishes your imaging, your realism (or not ;) )... which means for the real SQ guys, running them as low as possible (down to 50 or 60hz even, as you've observed), trying to get that "bass up front" illusion going.

    Your rear speakers, by contrast, you'll want to run as few frequencies to as possible... particularly, you want to kill them from playing any high frequencies, because the higher the frequency, the better your perception of sound-source location... and it's not natural to have sound coming from the rear. That's not how concerts are, that's not how sound is recorded. Music is recorded in "Stereo" - 2 channels - not 4. "Quadrophonic" died in the 70's (it was rather gimmicky), and 5.1 (DVD) is utilized in movies, not in musical recordings. Even DVD-A is recorded from what essentially work out to 2-channel masters (technically, masters have more than two channels... but from a recording position standpoint, I mean).

    There are also some very interesting acoustical considerations to be made.
    I've written an article that you should check out, regarding phasing anomolies and absolute phasing, acoustics in your interior, due to the very inherent varying speaker-to-ears pathlengths that exist in your vehicle... and why the more that exist, create more anomolies... why more will harm more than it will help... and even descriptions of situations where you might legitimately want to run rear speakers, and if so, how to maximize their advantage / minimize their degradations. B)

    Hope this is helpful!
     
  4. sandt38

    sandt38 Full Member

    Cody, check here for some TS param explinations.

    Also feel free to ask questions about whatever you don't understand. Hey, we were all new at this at one time. While many forums are geared around insulting and belittleing of those who aren't well versed in the hobby, I'd like to think that we can still remain polite and informative enough for you to feel comfortable to ask. Hell, those guys had to learn it from somewhere too. And consider this, what greater resource for CAT is there then somebody learning the ropes who becomes a wizz, who learned it here? Where will that persons loyalties lie? We want you to understand what we are saying, we don't want you to walk away frustrated and confused.

    I started that thread with the beginner in mind. But once we get some of these guys going technical we all venture off into left field :p . If you find us going off over your head, please ASK. I wanted to add to Dan Wiggins post to hopefully help the beginner understand the principles of the TS he explained.

    In my car (SD page, a bit old, but more detailed in some aspects, or This is a newer page) I use only a set of 6.5 Comps (100 watts per side) and a single 12 inch sub (1700 watts). My comps are crossed at 50Hz, my sub at ~65. I run a single set in the front for a more realistic soundstage. When you drive down the road, it sounds like the music is coming from right in front of the driver, at about nose level. When you run too many speakers frequencies overlap, get sloppy, come from all over creating auditory confusion, and all sorts of ugly things. If the speakers are distorting and you have all that power, turn your gains down, cross them lower (turn off all bass boost, "loud" or "media expander" functions.

    As far as missing frequencies, try reversing the polarity on your subs ;).
     
  5. PolkMM

    PolkMM Full Member

    thanks a lot guys
    ill definetely look into those sites you listed
    ill play with the crossover points a little, i have them set there b/c thats how ive seen a lot of systems crossed over at, and never really had a chance to tweak it to how i want it
    and i dont have any type of bass boost on, IMO, theyre worthless, the ones rockford fosgate have on their amps seem to be absolutely horrible, they make everything really sloppy
    so how did you like my little system?
    its not great, but its pretty good considering its my first...
    -Cody
     
  6. black00

    black00 Full Member

    too many words...must be about sq...

    :D welcome to the forum....

    my name is marshall my friends call me "poohbah" ........i'm nobody important.....

    Hi :bye:
     
  7. PolkMM

    PolkMM Full Member

    lol, yeah, im not too big into SPL
    thanks for the welcoming :D
    -Cody