GenVibe - Community for Pontiac Vibe Enthusiasts

First, a little background . . . my questions are near the end of the post.OK . . . just bought an amp today (and installed it myself - with MUCH help from a good friend - I suck at such things) and now my car sounds like I want it to sound. I still need to adjust all the settings on the amp (like I know how to do THAT!) but here's what I have . . . Head Unit - Premier DEH P790BT Front Speakers - Infinity Reference 6022i 6 1/2" coaxialsRear Speakers - Polk DB650 6 1/2" coaxialsSubwoofer - Pioneer TS-W256DVC 10" (350 Watts Nominal) (sealed enclosure)Mono Amplifier - Alpine MRP-M450 (400 Watts RMS x 1 at 2ohms)I've turned the high-pass filter off on the head unit . . . I think the four speakers can handle the full range if I don't crank the system up . . . I've been listening to it without the sub for about a week now and they do pretty darn well. When I turn the high pass on, it kind of "thins out" the music and it starts sounding a little overprocessed (did that make any sense?) . . . I have the sub set to -5 and the LOUD setting set to OFF. I have a custom EQ setting with the classic "rock n' roll" settings . . . a little high on the bass and treble with a bit lower midrange. I've had to turn the treble down a bit as I go because those Infinity Reference speakers are just so dang crisp. I involuntarily "blink" when there's a sharp snare hit - it's just very crisp and clear. I have the sub settings on my deck set to 80Hz. I just picked that because it's in the middle. I don't really know what I should have that set on. My amplifier settings are . . . gain - about 1/2 way upBass EQ - about +4 (on a scale of 0 to +12)LP filter - 75Hz (on a scale of 50 to 200Hz)My questions are:What should my amp gain levels be based on my system setup? You'll probably say I need to download some test tones and do some tests to determine the proper gain levels. But I'm not a basshead - I just want balanced sound with full range. Do I really need to set the gain that precisely?Should I be using the bass EQ (on the amplifier) or should I just set it to 0 and adjust the bass settings with the head unit? There are just so many options.How do I go about setting the LP filter on the amp? Should I match it with the settings I have on the HU? As stated above, my HU is set at 80Hz, and my amp is currently at 75Hz. Does a lower setting (e.g., 50Hz) mean that the sub will output only frequencies below 50Hz? And what will provide the cleanest, purest, most naturally balanced sound? Would that come from allowing the sub to play a wider range of frequencies, or a lesser range? Thanks for taking the time to read my post. Here are some pictures of my setup. Future plans - dump the 10" sub and buy an 8" Polk or Kicker with a smaller sealed box (space saver to please the wife). Future Future Plans - have a custom enclosure built into the spot where the stock sub is sitting OR trade that panel & enclosure for a standard one (and give up the idea of a custom box - SO EXPENSIVE!)

Well Eric,I gotta say i REALLY love post like this, you are really on your way to becoming audio literate...!!! I really like seeing all of the pertinent information listed just the way you have it... I do hope you learned a lot from your friend helping you with the amp install, we all have to start somewhere...Now, as far as HU settings... once you get the sub and amp back into the mix, you'll WANT to use that 80hz high pass on the deck. This will take the lower range out of the mid-high region, as you have already noticed. It will thin out the sound, but the sub should take over and fill it back in. This is WHY crossovers are used.. Right now you have 2 crossovers working the same thing but set differently. On the deck you have it set to 80hz and on the amp you have it set to ~75hz.... you should pick one or the other, not both... I would turn the "bass EQ" off for gain setting and then after you are done, you can play with it to taste... I cannot tell if you are able to defeat the crossover on the amp (not use it) or not? is that an option? Does it have a switch that looks similar to HP/AP/LP??? If it does, you will want the AP (all pass) setting. If not, use the amp crossover and defeat the deck crossover... Make sure you set the deck sub level output to 0 for gain setting, then you have a range of setting you can put the level to... I use this a lot depending on my mood, i can turn the bass up or down... Do you still have my instructions for setting gain (yes, it means you have to DL a 1000hz (1kHz) and a 60hz test tone, shouldn't be to hard to find) ??? You should consult http://www.bcae1.com/ on the ins and outs of gain setting, the topic is about 1/2 way down the topics section and has a really good tutorial on it... It's a little work, but it is very worth it...

Just to make sure I understand . . .use the high pass filter on the deckset either the deck or amp low pass filter to zero / don't use bothmake sure everything's set to 0 when I adjust the gainAnd . . . should the low pass filter be set to 200Hz? or 50Hz? Which setting will give more accurate sound?

Quote, originally posted by ericamity »Just to make sure I understand . . .use the high pass filter on the deckset either the deck or amp low pass filter to zero / don't use bothmake sure everything's set to 0 when I adjust the gainAnd . . . should the low pass filter be set to 200Hz? or 50Hz? Which setting will give more accurate sound? 1. Yep, you can try different setting, but you really want to remove the low bass from them, so they can do thier jerb.... mids and highs... 2. Yep, unless you set them the same, then IIRC they double up, meaning if the deck is 12db/octive and the amp is 12db/octive you end up with 24db/octive slope..3. Yes, you want to set the amps INPUT sensitivity (or gain) to the decks output. After you can play with the various EQ's and boosts... Low pass is just as subjective as the HP, but once you get over ~100hz the subs start playing mid-bass information... I tipically set around 100 for the sub, so they can pick up some of that mid-bass... but the lower it is the more efficent the sub will be... The main thing with subs is the weight of the cone... at say 60hz that cone is moveing out away from it's resting point 60 times per second... and in away from it's resting point 60 times per second... (to make a full waveform) Now consider that at say 125hz... that cone is going CRAZY and all of that weight has to be controled somehow.... Much of this is done by the box, but some definitly is done by the amp.... Now consider what is happening when you have a RANGE of frequencies going to a sub and it is playing them ALL at the same time, including harmonics... WoW

I have it all set . . . but the only problem is that I don't seem to be able to turn "off" the LP filter on the HU. I also can't turn it "off" on the amp. So right now, I have the deck set to 100Hz (I'm assuming that means all frequencies up to 100Hz will be allowed to go to the sub) and I have the sub set to 80Hz. My thought was that the sub (being at a lower setting) would override the HU. Dunno. Thanks for the responses. Without you this wouldn't be much of a forum (at least not for me) . . . thanks again.Eric

Well, if you can turn off either, set them the same...