Bass Louder and softer sometimes... Bass subwoofer problem - Bass loss

BassErex

CarAudio.com Recruit
Hello! From above, sorry from too long entry, I wanted to present my problem well. And I'm asking for advice :)
.
I have weird problem of bass from subwoofer. I fight with this about 4 years On two cars: Mazda 323f Ba and Mazda 6.
Sometimes bass is much better and softer. and sometimes i can feel better presure, but car body shake is the same. Mostly my bass sound is SH*T (sorry).
I see voltage, and if bass is very very nice, no diference with voltage drops ( Reading from amp terminal)
Voltage drops are small, so, its cant be a problem
My system on today:
Mazda 6 2007r Wagon 2.0.
Hifonics BRX 12000 + Audio System XIon 15-1000 (Wired 2 ohm)
Rodek 2180A + STX pa 1000 coppy on rear seats (Sorry, its not good but should not make problems, on mazda 323f ba the music was from the doors and this same problem)
My Head Unit is now alpine cde 178bt
My power:
- Lithium YINLONG 2 Packs (80ah) in trunk
-Alternator 300a (14,5 - 15,4V)
Wires Power:
- 2x 50mm2 from alt to batt (Sorry i dont know how Ga or Awg, I;m from polen) All wires 100% copper
- Sub Amp Hifonics 2x 50mm from terminalls (about 0,70m lenght)
- Rodek 1x 16mm2
Grounds Wires:
-1x 50mm2 from alt to chasis, and from chasis to batt
-1x 50mm2 from engine to chasis, and from chasis to batt
- 2x 50mm2 from battery to nearest chasis point
- Hifonics Grounds 2x 50mm2 is from lithium batt terminall, per ground wire is about 1,5M lenght (its problem? too long?)
Problem is going on this two amps, amp from music i have too diference with bass, are louder can be.
I checked:
- Grounds, looks nice
- Connections fuse, power wires, Sub speaker wires. (no lose)
-Rca connections on HU and amp, very tightly.

About this 4 years i tested:
Much amps (Emphaser ea 2500, Vibe Mono 21k, kicx ad 1.400)
Subs (2x 15 excursion sxx 15v2, Pa subwoofer, clarion sw 3012)
3-4 of PCS rca (I now from sub have Pride diamond)

Kenwood x7200dab Hu, and pioneer 3500ui.
Speaker wires.
Sometimes bass loud and soft can back but not always if:
I REconnect amp power
Change Port subwoofer (to lower or higher tuning)
Bass can back if i a few times put subwoofer to trunk, roof, trunk roof, trunk roof, can sounds be better.
Bass like run away, if most offen i restart engine.
Today i checked all connections, In sub box terminal very nice
tightened. Speaker wires are good.
I have a osciloscope, no distortions from hu and amps but:

My weird looks:
Volume on hu max 35
to 10 sound bass going up, 10 to 15 stop to sub, but music going up WFT?
I tried to see voltage output from hu, and i have problem to Get nice output voltage,
Cliping at 4,4v, but i put Preamp source USB is FULL, and i have full no cliped voltage about 4 volts on 32-33V on radio with Bass boostloudness off and flat EQ.
On aux From my xiaomi on full preamp source on hu, i have on good music max 1,2v.
I Set my gains property clean, with full clean voltage output Hu, but with sound quality and hitting bass, no diferences...

Any questions? Too long grounds amps? Thanks.
 
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Do you have large temperature differences where you live? I live in Norway, and in winter time when it is -10 Celsius out side. The low frequency sound signature is different until the subwoofers warms up and the suspension softens. I can hear the same in summer time if it is very hot, the bass is softer and deeper. It is not a big audible difference, some don't notice, but I certainly do.
 
Do you have large temperature differences where you live? I live in Norway, and in winter time when it is -10 Celsius out side. The low frequency sound signature is different until the subwoofers warms up and the suspension softens. I can hear the same in summer time if it is very hot, the bass is softer and deeper. It is not a big audible difference, some don't notice, but I certainly do.
Yes, I have a difference, but my difference is HUGE. The difference can be so big, as if I had a sound system in about 150-200 dolars (with wires amps subs LOL)
in the meantime I added good components about 5000 dolars.
It also played well in the cold, but sound like, resistance change in warm temperature. And sound may be worse about next engine start...
For those who are looking for a problem: Look for the cause of the tension on amp bodies,
or in other places
I'm sure that's the cause of problems. This same issue i have at home, but i have not grounded home, my leds in home if are switch off, glow gentlies. And sounds from my PA amps at home is also different!

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!!! UPDATE!!!
Hello again. On this season i upgraded sytem to 500Farad super caps. Result? this same.
I sent the amp and it was checked and brought to life (RECAP) but efect? BadAss Bass.

BUT!!! I know the reason, why bass is sh*T
Its a
GROUND LOOP! This is a.. phase shifted, but in a signal.
that explains it, why bass in garage is awesome, but in car no...
Moving sub, bass can back (Ground loop Feedback)
Ground loop can induction voltage (on my amp body) Thats right!
I have Noises on bass amp and werd sinusoidal wave (distorted)
The noises is this same with connected rca and disconected. 0,3-0,5 volts noise.
But i dont know how fix this issue.
connection Source with preamp and amp2 from the bass amp terminall not working.
When i good no iduction voltage (Source ground with 1mm wire only with source body, outside car and back to trunk witch rear doors and to - supercaps, amp) be fine but if i start amp, voltage up to 0,2 volts.
I found a video that describes the problem, but I can't quite understand it. Whats wires itp.
Any help? https: //www.youtube.com/watch?v=xbinXh1ZSqk&list=LL&index=1&t=492s

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Hi, i dont have front battery, all audio equipent is connected to the battery in trunk.
Have you tried running a ground from the main battery to the back, where the amp is? You don't ground it to the amp. You just ground it to the point where the amp is. Also, if you have a battery isolator, it might be interfering as well.

Have you also tried grounding the shielding on your RCA's?
 
Have you tried running a ground from the main battery to the back, where the amp is? You don't ground it to the amp. You just ground it to the point where the amp is. Also, if you have a battery isolator, it might be interfering as well.

Have you also tried grounding the shielding on your RCA's?
  • Jun 15, 2023
    Hello! From above, sorry from too long entry, I wanted to present my problem well. And I'm asking for advice :)
    .

Hopefully, in the last year, he got it all figured out! ;)
 
Have you tried running a ground from the main battery to the back, where the amp is? You don't ground it to the amp. You just ground it to the point where the amp is. Also, if you have a battery isolator, it might be interfering as well.

Have you also tried grounding the shielding on your RCA's?
I checked exactly what it looks like, its only a weird output from amplifier. Engine off, rca unpluged on amp, speaker wires unpluged, and.. I have 0,512 volt noise, (sometimes about 420 hz sometimes above 800 hz noise). If i start engine or plug rca, nothing change, i have too this noise, DC output on 0,3 volt drop on music is about 0,2 volts on my amp! lol. What to do in such a case?
 
Uptade: since I started using a ''good'' resistance meter. on my side it is UNIT 204+ i see loosing performances.
Resistance beetwen SUPER CAPS and MY amp input is with off system 1 ohm, amps on 13 ohms, on playing music with 0,3v drop i see 80-300 ohms!!! sometimes ground be okay and high resistance go to + wires.
The problem: Conncector on a connector is loose several ohms. And next problem is wires, between connector from supercaps and to cable sleve i read 5 ohms with only amp on!!! (37% loose power)
This is a connection loss issue. search only with reading resistance to fix problem!!!
 
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BassErex

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