chio987

ok. i finally got around to build a box for my sub and need to know hoto tune it right (or is it whatever i think sounds good) like should i adjust the low pass, bass boost, then gain. or bass boost, low pass, then gain?? i don't understand what 40-350 means on the low pass or 0- +12db on the bass boost.

here r the specs of the sub

Model--------------------RFS-1815
Nom. Impedance--------------8
FS (Hz)------------------------27
RE (Ohm)----------------------6.7
LE (mH)------------------------2.87
QMS----------------------------3.90
QES----------------------------0.59
QTS----------------------------0.51
VAS (cu.ft)-------------------11.336
VAS (liter)--------------------321
Power (Watts RMS)-------150
Power (Watts Peak)------300
SPL (dB @ 1w/1m)--------93
X-MAX (inches)------------0.23
X-MAX (mm)------------------5.9
Speaker Dis. (cu. ft.)--------0.107
Mntg. Dia. (in.)----------------14 14
Mntg. Depth (in.)-------------6-3/32

if some one could even paint little marks on the pic to show where u would adjust them, that would be great.

Thanks

EDIT: lol, o ya. it's a 800 watt pyramid amp PB-580

chio987

anyone or am i asking a question that can't be given an answer?

Half-FastRacing

Chio -

I stumbled upon this site a few years ago. You will be interested in #63 (Gain Controls - Found on menu on right, scroll down) at first, but I suggest reading the website in it's entirety.

http://www.bcae1.com

You will probably also be interested in #84 (Electronic Crossover vs. Passive Crossover)

To any and all that find this site useful...give back and buy his CD version of the site.

chio987

thanks for the help. that's a good site, i've been there once b4. but i didn't understand one word of that. but it seems that i don't want to turn the gain up all the way or something and i'm guessing that u'd need to know what head unit i have and i'll have to try and find out what the vrms is (vrms??)

TomP

What size fuse is on the amplifier?

Also, yes, we'd need to know the rest of your system, other amps, speakers, etc.

chio987

the info for the sub and amp r in the original post....i can't find a DAM thing on the HU, not even on clarion's web site mines a DRX-6475 and the closest they show is a DRX-6575z. here's a pic....40Wx4

EDIT: believe it or not that pic was scanned, so if u need a bigger pic, let me know (idunno if u even need the pic)

Half-FastRacing

Chio - It says right on the picture you scanned...on the bottom left corner of the deck...4volts. According to the www.bcae1.com website, you would set your gain/level to 4 volts.

Just to let you know, your amp makes 500 watts RMS when bridged into a 2ohm load...but you will be putting an 8ohm load to it (That is if you have a single voice coil 8ohm sub as described in your first post). This means an 8ohm load should bring that amp's output in the 125 watts RMS range. This is fine seeing as your sub is rated to handle 150 watts continuous.

Although you have an efficient sub (93dB sensitivity), I am not sure it will reach the levels you may want. Is the box ported or sealed? You will definitely want to put the switch to "low pass" and from experience (no documented source), I would set the frequency to 80hz (15" sub may need lower)...or close since the dial doesn't have that exact number.

I personally leave bass boost at 0. But having an 15" 8ohm sub may lead you to turn it up. Just avoid clipping/distortion. A test and tune type thing with bass boost.

Edit: I now see that your amp doesn't have a numerical setting for the level...so all that you read and learned is out the window. Just turn up the dial until you hear distortion at 70% volume...then down a hair...lol

chio987

sry i forgot about the fuse, it's a 20 amp

Half-FastRacing, so should i put the gain to 4v. my HU goes to vol. 33 and i almost never go above 20-21. so i should put my vol at 20 and turn up the low pass until it distorts? and do those # on the low pass the frequency?? it's a 3cft sealed box

the gain should be like the pic??? i didn't even realize what that 4V HVO thing was. EDIT: the pic on the right

chio987

T.T.T.

Half-FastRacing

Chio - I think it would be less confusing if we focused on the picture of the amp you posted.

First thing, turn off your bass boost (0dB) and turn your level to "min"

According to the picture, it looks like your low pass frequency is at a good place to start. Move the "Crossover Mode" switch to the low pass position (it appears to already be there in the picture). Turn the volume way down....10 or so...and put your ear to the cone of the subwoofer(this is why the volume has to be low). Can you hear any treble coming from the sub? If so, turn the dial counter clockwise towards "40" until the treble is much quieter or gone.

Raise head away from cone of speaker. With your level still at "min". Turn the volume up to 20...turn up the level slowly, trying to listen for distortion. When you find that point, turn the level down just a hair so that the distortion is no longer audible.

Lastly, time for the bass boost. If needed at all, keep volume at 20 and slowly start to raise bass boost from 0dB towards...but no where near 12dB. This is another test and tune thing...Your ear should tell you when to stop.

chio987

i think i understand. and i don't have anymore questions, i'm just posting to say thanks to everyone :hail: