I realize that the usual advice is “change the settings and go by your ears”, but I’m such a novice that I’d like to get some opinions about what settings to start from.
I have a 2000 base Miata with:
1) Alpine CDE-105B head unit (http://support.alpine-usa.com/produc...E-103BT_EN.pdf),
2) Alpine PDX-F4 amp (http://support.alpine-usa.com/produc...0PDX-F6_F4.pdf), bridged to provide 200 WRMS at 4 ohm to the sub,
3) Polk db571 full range 5x7 door speakers (http://www.polkaudio.com/caraudio/sp...systems/db571/),
4) Polk dB1001 tweeters (http://www.polkaudio.com/caraudio/db/specs.php) wired in parallel with the db571’s, presenting 4 ohms, and
5) Bazooka BT6028DVC 6 inch 8 ohm Dual Passive Tube subwoofer in the trunk, (http://www.bazooka.com/products/mobi...ssive-Tube-P26) wired parallel presenting 4 ohms.
a) The HU (CDE-105B) amp is off. It has these settings:
i) bass center frequency = 80 Hz, 100 Hz, 200 Hz, 60 Hz,
ii) bass bandwidth = 1, 2, 3, 4 (narrow to wide),
iii) treble center frequency = 10.0 kHz ,12.5 kHz, 15.0 kHz, 17.5 kHz,
iv) high pass filter frequency = OFF, 60 Hz, 80 Hz, 100 Hz,
v) loudness contour = on/off,
vi) defeat = on/off.
b) The amp (PDX-F4) has a crossover, variable, 30-400Hz (-12dB / oct ), Low-Pass/High-Pass/OFF for both front and rear channels. Front channels are set to Low-Pass 80Hz.. Rear (sub) channel is currently set to High-Pass 80 Hz,
c) Front speakers have a range of 52Hz-22kHz and a sensitivity of 93db,
d) Tweeters have a range of 4kHz-23kHz,
e) Sub has sensitivity = 100 dB , and frequency response = 35Hz-250Hz.
I have two pair of Harrison Labs FMOD High Pass Crossovers (12db per octave slope, one pair 30 Hz, the other 50 Hz, one pair to be returned) that I plan to put in series with the sub for eliminating infrasonics, and a Brand-X LXSCAP17 1.7-Farad Capacitor for the amp.
Whew. So my question is: What do I do with all these settings? Should I:
I) Overlap the front and sub channels on the amp, say 100 Hz HPF for the sub and 80 Hz LPF for the fronts, per http://www.soundstage.com/maxdb/maxdb200101.htm, or set them both to 80?
II) Set the amp’s bass center frequency to 80 Hz with the widest possible amount of boost, and the treble frequency emphasis to 15 kHz or 17 kHz, per http://www.caraudio.com/forum/head-u...equencies.html?
III) Bazooka Tech Support recommends the 30 Hz bass blocker, so that seems easy, the 50 Hz one goes back to Amazon ... My first thought was since these are first level devices, the rolloff would be higher at frequencies below the nominal, say 50 Hz, so I would go with 50.
Also, lacking an oscilloscope like Richard Clark recommends at http://www.davidnavone.com/heresHow/...evelSet222.pdf, I had to resort to a procedure like that at http://www.polkaudio.com/forums/showthread.php?t=17905, “turn it up til it distorts then back it off”, except that I could not get any distortion at sound levels I could stand. I can’t find anyone around here who has or is willing to use a scope, and don’t really want to buy one for a single use.
I appreciate you reading this far, and would appreciate your comments even more.