Okay so about 8 months ago (give or take a couple months) I installed a setup in a 1965 Mustang. Upfront it has a yellow Optima and 120 amp alternator (yes, I know that needs to be upgraded and it will be). The head unit was an old Custom Autosound USA-1 (a real POS) but is now a Retrosound Detroit motor 4 (the head unit isn't as important but both are designed to fit the original dash with no cutting). I hoped a new radio would fix my issue but it didn't. Four Kicker (junk, in there when I got it) speakers in the cab powered by some four channel Kenwood. Then the subwoofers are 2 Alpine Type R 12s wired to 1 Ohm in a custom sealed box powered by a Hifonics BXX3000.1. I dont know how you guys feel about Hifonics but long story short it isn't the amp I clicked "buy now" for. Forgot the cubes of the box but it was within spec when built.
Anyway this setup used to be beyond loud enough (mainly older rock but the occasional rap demo for a friend) however one day I noticed the bass was quiet. With the bass knob, I have to max it out to get quiter output than 1/4 to 1/2 of a turn used to get me. Keep in my mind I set all my gains with an oscilloscope as well. Playing a test tone the subwoofers still seem to get very loud but when playing a song the four cab speakers usually overpower the bass, before it was the other way around. The sub amp has 1/0 guage wire and a bare metal ground to the chassis where a large bolt is located for the bumper. My RCAs measure 2.85-3v. The day the bass seemed quieter nothing had changed from the previous day. Solid connections to the amp, 1 ohm at the subwoofers (yes I checked everything with a multimeter), about 3 volts at the RCA, gains set with an o-scope (-5db), and I recently took out my box to reseal it and double check the subwoofer's wires as well as their suspensions. Everything seems to check out. I've been through the settings in my radio as well. The cab speakers are much louder than the bass. I'm open for any suggestion and willing to double check anything I already have. If everything seems to check out then why might my bass have gone quite to never return?
As another note, the amplifier still pulls enough to get some voltage drop (headlight flickering). Before the bass went quiet, there would be no voltage drop when at a comfortable listening volume (1/4-1/2 on knob). Now there almost always is voltage drop when at a comfortable volume (knob maxed out). Further more, if P=V^2/R is any indication of wattage then this amp puts out around 1900 watts with a clean signal output. I'm not sure how that wattage compares to the wattage it put out when the bass was louder however it may be significantly lower than the stated 3000 due to manufacturers lying and a weaker alt (this amplifier could put out more with a better alt.). I don't think it's the amplifier dying?
I apologize for the long unorganized post. I've been working with this setup all day and have a massive headache. Thank you to everyone who took their time to read it.
Anyway this setup used to be beyond loud enough (mainly older rock but the occasional rap demo for a friend) however one day I noticed the bass was quiet. With the bass knob, I have to max it out to get quiter output than 1/4 to 1/2 of a turn used to get me. Keep in my mind I set all my gains with an oscilloscope as well. Playing a test tone the subwoofers still seem to get very loud but when playing a song the four cab speakers usually overpower the bass, before it was the other way around. The sub amp has 1/0 guage wire and a bare metal ground to the chassis where a large bolt is located for the bumper. My RCAs measure 2.85-3v. The day the bass seemed quieter nothing had changed from the previous day. Solid connections to the amp, 1 ohm at the subwoofers (yes I checked everything with a multimeter), about 3 volts at the RCA, gains set with an o-scope (-5db), and I recently took out my box to reseal it and double check the subwoofer's wires as well as their suspensions. Everything seems to check out. I've been through the settings in my radio as well. The cab speakers are much louder than the bass. I'm open for any suggestion and willing to double check anything I already have. If everything seems to check out then why might my bass have gone quite to never return?
As another note, the amplifier still pulls enough to get some voltage drop (headlight flickering). Before the bass went quiet, there would be no voltage drop when at a comfortable listening volume (1/4-1/2 on knob). Now there almost always is voltage drop when at a comfortable volume (knob maxed out). Further more, if P=V^2/R is any indication of wattage then this amp puts out around 1900 watts with a clean signal output. I'm not sure how that wattage compares to the wattage it put out when the bass was louder however it may be significantly lower than the stated 3000 due to manufacturers lying and a weaker alt (this amplifier could put out more with a better alt.). I don't think it's the amplifier dying?
I apologize for the long unorganized post. I've been working with this setup all day and have a massive headache. Thank you to everyone who took their time to read it.
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