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

[BassErex]

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.

Click to read more...

 

[1aespinoza 10+ year member]

Any questions? Too long grounds amps? Thanks.

From your description, it sounds as if you have Auto Volume Leveling active. I know you have aftermarket radios and two different vehicles, but it sure sounds like that is the issue.
A quick test is to connect your phone direct to the amps and use it a few days. This will tell us if the issue is the audio source or the amplifier section.

 

[BassErex]

From your description, it sounds as if you have Auto Volume Leveling active. I know you have aftermarket radios and two different vehicles, but it sure sounds like that is the issue.
A quick test is to connect your phone direct to the amps and use it a few days. This will tell us if the issue is the audio source or the amplifier section.

Hello. Sorry,

It wasn't written this. I checked this way. seem to be better (Bass cleaner). but still missing more effect, maybe because output from phone is about 0,1 volts?
I also tried connecting My hu to my old Lead acid batter without any other instalation connected. (custom HU instalation is one 4mm to trunk battery power and this same ground, and remote). The effect was worse

 

[1aespinoza 10+ year member]

seem to be better (Bass cleaner). but still missing more effect, maybe because output from phone is about 0,1 volts?

So with the phone method you had no fluctuation, only the lack of better output from the amps? With less power they play fine. If so, then maybe your subs are playing beyond their capacity in the box you have them now. I think the term for that is called offloading. Don't quote me on that.
Was the box made to sub specifications or for SPL purposes?

 

[BassErex]

So with the phone method you had no fluctuation, only the lack of better output from the amps? With less power they play fine. If so, then maybe your subs are playing beyond their capacity in the box you have them now. I think the term for that is called offloading. Don't quote me on that.
Was the box made to sub specifications or for SPL purposes?

I had an impression, that was better. softness was missing, maybe actually the installation of the car affects my HU, or signal?
Or rather, an electromagnetic field? When by signal boost from phone with equalizer, maybe everything would be fine.

My sub xion 15-1000, Excursion sxx 15 x2 v2. boxes is made for SPL/Sq, Boxes designed and made by a person, who does good results in car audio.
It just seems hard to me that it could be the box's fault.
for the my previous car (mazda 323f ba) I put 18' pa subwoofer, which shouldn't play good.
then i had 18p1000fe beyma 4ohm in 145l netto box and 42hz tuning on amplifier Kicx ad 1.400 and HU pioneer deh 3500ui.
I had a bad install then, 16mm2 ground and bad 7mm power wire.
First test subwoofer on normal music, didn't make an impresion. But! when music go under 40hz, bass was amazing.
I played songs from 30 to 40hz. It was the longest good sound for me, 3 weeks of awesome bass, after this time bass align with frequency above 40hz. Conclusion, the problem was all time with this 3 weeks, but above 40 hertz...

It's hard for me to explain this problem..
Sound like, as if the phase was far away, but delays on HU no diferences with this...

Edit: i'm called to ex owner my alpine cde 178bt. His sources he dind not have conquered and more, he had a strong signal on rca,
I wrote to the person, who had Kendwood X7200dab. He had the same, Sub level on hu was even below zero, no boosted anything, and he has volume to max output about 22-24vol. I had on this kennwood volume about 29-31 and sw +7 from 10...
Voltage on Hu isn bad, only remotes to amps dropning voltage from 14,6 to 14,34.

 

[1aespinoza 10+ year member]

I had an impression, that was better. softness was missing, maybe actually the installation of the car affects my HU, or signal?
Or rather, an electromagnetic field? When by signal boost from phone with equalizer, maybe everything would be fine.

I have thought of this issue all day and still coming up blank. I do suspect the signal but you said previous owners had no issues with either radio. You mention maybe trying a signal booster like an equalizer; I thought more along the lines of a line output converter. But this does not get us to the core issue.

My sub xion 15-1000, Excursion sxx 15 x2 v2. boxes is made for SPL/Sq, Boxes designed and made by a person, who does good results in car audio.

Do you know the specifications of the box. I found this spec sheet for your sub.

It just seems hard to me that it could be the box's fault.

Oh yes. A bad box can make a good sub sound terrible. You say the old set up sounded great from 40 hertz on down. Above 40 hertz it was not good. This sounds more like an SPL box rather than an SQ box. You are missing out on the upper bass notes that your front stage cannot fill in. So I am leaning more towards a improperly tuned box or wrong x-over settings.

 

[BassErex]

I have thought of this issue all day and still coming up blank. I do suspect the signal but you said previous owners had no issues with either radio. You mention maybe trying a signal booster like an equalizer; I thought more along the lines of a line output converter. But this does not get us to the core issue.

Do you know the specifications of the box. I found this spec sheet for your sub.View attachment 49706


Oh yes. A bad box can make a good sub sound terrible. You say the old set up sounded great from 40 hertz on down. Above 40 hertz it was not good. This sounds more like an SPL box rather than an SQ box. You are missing out on the upper bass notes that your front stage cannot fill in. So I am leaning more towards a improperly tuned box or wrong x-over settings.

The pa sub played awesome under 40hertz music, but only 3 weeks. Then this time, never did not play good (I didn't change anything in the settings).
My box for xion 15 is about 110L netto and 35hz port tuning 8' aeroport
Excursions subs is about 200l netto and 33hz port tuning with 8' aeroport, (I can change ports to get 25hz tuning, and 40hz tuning)
My Xover: HPF 100hz for Music, and sub 80Hz from 18db octave (I hear diferences with change filters cutting hz, but its not very big diference.)

 

[1aespinoza 10+ year member]

Excursions subs is about 200l netto and 33hz port tuning with 8' aeroport, (I can change ports to get 25hz tuning, and 40hz tuning)

I could not find specifications for the X-Ion 15.

My Xover: HPF 100hz for Music, and sub 80Hz from 18db octave (I hear diferences with change filters cutting hz, but its not very big diference.

Those settings look good. I set mine by ear. All subs have their unique sound. I was using a conventional sealed 12 with the Low Pass at 80Hz/24dB. I changed to flat subs and had to set Low Pass at 65Hz/24dB.
Do you have the specs of the sub you are currently using?

 

[BassErex]

I could not find specifications for the X-Ion 15.

Those settings look good. I set mine by ear. All subs have their unique sound. I was using a conventional sealed 12 with the Low Pass at 80Hz/24dB. I changed to flat subs and had to set Low Pass at 65Hz/24dB.
Do you have the specs of the sub you are currently using?

That's the problem, we couldn't find manual.
But
i think, Box came out pretty well.

I try to pull signal from my OLD hu pionner, who play in the car Renault Kangoo, i have there Clarion sw 3012 + **** Crunch amp100w , but its play much cleaner, and there are no such circues...
I suspect the my Audio system would work there perfect
Despite the poor acoustics.
In mazda i have sound profed Roof with 1x 2mm Russian matt, 2x 2,5mm Bitmat Ab 25 and Bitmat K9s.
Trunk 1x 2,5mm bitmat ab 25, and tailgate trunk 3x 2mm russian GB 2mm matt.
Diference before and after soundproff is Zero :/

 

[Jimi77 5,000+ posts]

One note wonder box??? Try plugging the port and see what happens.

 

[1aespinoza 10+ year member]

That's the problem, we couldn't find manual.
But

Wait, the spec sheet I posted above is for these 15" SX X-Ion. Is the current box close to those specifications?
BTW, nice set-up, very clean. On another note, wagons are awesome for bass systems.
According to the manual, you need a 70 square inch port per sub. The 8 inch aero port has 50.24 square inches.
Port length should be 11.8 inches long.

 

[BassErex]

Wait, the spec sheet I posted above is for these 15" SX X-Ion. Is the current box close to those specifications?
BTW, nice set-up, very clean. On another note, wagons are awesome for bass systems.
According to the manual, you need a 70 square inch port per sub. The 8 inch aero port has 50.24 square inches.
Port length should be 11.8 inches long.

To Audio system Xion 15, No manual on net, On sxx 15v2 box is made for subs, yes port too small :/ but I don't think that's the reason (my friend have **** low quality subwoofer, but its play better for sound quality). If in another car the same equipment will be able to sound better.
However, I will look for the cause of the car's electrics

One note wonder box??? Try plugging the port and see what happens.

I tried all possibilities. Its can work, but only for short time and problems back :/

 

[BassErex]

UPDATE:
I think, problem found,
I didn't really notice anything else... So
Talking to someone about this problem, I mentioned it that giving multimetr cables to ground connect amp, and to amp body, i see voltage on multimeter, on my Hifonics brx 12000, when i give multimeter wires to ground and amp body, voltage is about 11v and dropping, it can drop to 0 volts but on lower voltage ( under 1 volt) voltagr drop is slow.
Hecking voltage on rodek 2180a, no droping, voltage this same what the battery...
Now i tested voltages: Rodek: 0,000v volt, BRX 12000 0,7v.

It was the same with another subwoofer amplifier, so amps is fine.
Today ride from my work, bass so nice, soft, loud and feel good presure on body....
it must be a problem,
it can also affect rca signal, if i put on rca connector ground multimeter wire, and for body car i have this same voltage (0,7 and drooping)
Do you know what this is about?

 

[Doxquzme Premium Member]

I've been building loudspeakers for 40 years, and the way I read the spec sheet, you are about 50L (net) to small on the box for 2 of these 15" woofers. This might sound decent on some playback and not on others, not how it should sound on anything! Gross internal volume for two drivers should be 180L gross (150net) tuned to 60Hz (vb) which will yield a 50hz response (which would be almost 4 octaves down, so I'm not sure what they are telling you there). Given the Vb and the tuning frequency of 60Hz, 57Hz would be your 3db down point, not exactly low in my book but not atypical for a larger driver. You can't just tune a box to your liking, where you think or want it to play; it needs to relate to the specifications of the woofer, the box and the woofer work together. According to the specs you list for the SPL box (the smaller option in this case), you need 180 liters of gross volume (this is the volume before negating the woofer drivers and the port displacement), 75 liters of net volume, or Vb at 75L per chamber (150L net for two drivers), and the port they recommend is 30cm x 12.5cm or 375 square centimeters, for the rectangle port opening with a length of 27.5cm. I didn’t do the conversion from round to rectangle (375sq cm is equal to an 8.25" port, maybe?), but I am guessing the port you are using is completely wrong. The resonant frequency (the point where the woofer vibrates undesirably) for this woofer is 35hz. Unless you are using a subsonic filter crossed at 20Hz, you shouldn’t tune below 35hz. This box does not appear to be correct for two woofers (not even close). The box you have is half the size it needs to be. These woofers are never going to perform correctly in this enclosure. It is important to note, larger woofers do not necessarily and in most cases, do not play as low as 10’s or 12’s usually do, or at all for that matter. 15’s rarely play lower than 12’s, they just move more air (are louder). Try disconnecting one of the woofers, closing up that opening (temporarily) and see if the sound is more to your liking. I think you need to think about starting over on this box. I have BASS box pro and can run the specs if you need, for an extended bass box tuned to 35-40, but it looks like it will be on the order of 6-8 cubic feet given the parameters that I found ( https://www.carhifitwente.nl//Files.../Product/3m9ky7D682XXT075Y3ZXm6T8mQ9100pf.pdf), that’s a REAL big box! Thid subwoofer, with a Qts of .83 and an EPB >50 is meant for ported, not sealed enclsures. Stuffing the port will not change this. These woofers are meant to perform best in ported enclosures.

 

[JohnPD]

What is your voltage drop? Ideally you want it less than .05v difference from what it is at the battery, and what it is at the amp, and anywhere else you test it.