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I’ll do you have a friend with a stereo?   I’d see how it sounds putting  his box in your car and running it with their amp and then just running wires to your box in your car from their amp

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7 hours ago, CstrokerV said:

I’ll do you have a friend with a stereo?   I’d see how it sounds putting  his box in your car and running it with their amp and then just running wires to your box in your car from their amp

I don't have. I did test the system with another amp another box and another Radio results were the same. This led me to believe that there was no problem with the signal from Radio up to the outputs of the amp, led me to believe it's the car acoustics, namely its shape. Under the trunks carpet there is a hollow area for the spare tire. This car version has instead of the physical spare tire a small flat tire kit, so that the area under the carpet is very hollow.

 

I still need to eliminate the possibility that the whole signal is clean from source to output. I think I will buy an O-scope, in spite the fact we have already tested that the signal is clean at that shop, in spite the fact this amp has a clip indicator but whatever, I want to do this alone.

 

Back to that hollow space under the trunks carpet, I seriously think that's causing this bass overload @ around 50Hz. Because this topic is so long, I will have to quote my earlier posts, when I specifically said that once I set on the GraphEQ the 50Hz Band to Minus 6db (max) bass output is way cleaner (this with the sub in the trunk, where it shouyld always be). Also when I put the sub box on the back seat it reproduces the same cleaning effect with a flat EQ, so without reducing the output of 50Hz band.

 

The subs output with a sine sweep 30hz-120hz sounds weird.

30 - 42Hz ok-ish but still a bit overmphasized

43 - 48Hz this is very weird, as the bass output silences, I get a huge dip right here, it's like that hollow space is cancelling these waves

49 - 65Hz ok-ish still overmphasized

66 - crosspoint (80Hz) again a huge dip, bass output silences.

* all of these happen when the sub is located in the trunk area, it doesn't matter it's firing position or its position whatsoever

Now when I play the same sweep when the sub is on the back seat I get a clean output no overemphasis and no dips.

 

I am thinking that hollow space under the trunks carpet doesn't allow this car to be pressurized like it should. In my other car Peugeot 206 once you lift the trunks carpet everything is bare flat metal like you see below, there is no hollow space for the spare tire. 

 

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That makes no sense to me about the spare tire well .. I’ve  had cars that loaded fine with them... can you fit the box there ?  Or have the shop build the box into it see if that helps...  lol just talked to my friend he’s 6 foot and with the depth of a havoc 18 give a few inches he was never comfortable driving but might of fixed that if we designed the box different it was sealed so who knows

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It's the only thing left in the equation, that hollow space. I don't have a custom box for that tire well there and I don't intend putting anything in that hole. I think I may need to somehow seal that location with some custom thick mdf plates and need to think of a good rubber isolation or something.

 

The trunk is like a second sub box for the passengers isn't it? Like how the car is a third sub box for someone standing outside. That is why I am thinking that that hollow space is the culprit. It's ruining the bass output as it makes its way to the passenger side.

 

Quick throwback, I remember since I got the first sub in this car, it sounded like this since the very beginning with different amps, different Radios, different cables lol. It sounded like this since I got it upgraded, has this "uuuuuuuu" sound, every bass note from those overemphasized fre intervals (30 - 42Hz and 49 - 65Hz). I remember this clearly. The bass sounded like this since the very beginning lol. SO yeah, the trunk must be the culprit!

 

I have changed so many things I invested over 4k in this and I hope this is the reason why and once I isolate that tire well hollow space I will know.

 

 

I found a specific video on youtube. The guy testes 2 sub-amp combos with an OEM Radio.

1st combo: an active sub

2nd combo: a passive sub with a separate amp.

The trunk of that car has that tire well which starts to deepen only at the hole, but it's not that hollow like mine is, mine is 10cm deeper and then it deepens even more for the spare tire to fit.

 

So as the guy tests the 1st combo with the active sub, everything is nice. Then tries the other combo and his face is exactly like my face lol. The video has CC subtitles too, what he concludes with the 2nd combo ist that bass is overemphasizing.

Link to video: https://www.youtube.com/watch?v=TFpfAfIofOY skip to the 24 Minute to see his face. He didn't explain why it sounded like that with the second combo. He just stated that the power of that Mosconi Pico amp is somehow not compatible with that sub...

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2 hours ago, Qwiz said:

It's the only thing left in the equation, that hollow space. I don't have a custom box for that tire well there and I don't intend putting anything in that hole. I think I may need to somehow seal that location with some custom thick mdf plates and need to think of a good rubber isolation or something.

 

The trunk is like a second sub box for the passengers isn't it? Like how the car is a third sub box for someone standing outside. That is why I am thinking that that hollow space is the culprit. It's ruining the bass output as it makes its way to the passenger side.

 

Quick throwback, I remember since I got the first sub in this car, it sounded like this since the very beginning with different amps, different Radios, different cables lol. It sounded like this since I got it upgraded, has this "uuuuuuuu" sound, every bass note from those overemphasized fre intervals (30 - 42Hz and 49 - 65Hz). I remember this clearly. The bass sounded like this since the very beginning lol. SO yeah, the trunk must be the culprit!

 

I have changed so many things I invested over 4k in this and I hope this is the reason why and once I isolate that tire well hollow space I will know.

 

 

I found a specific video on youtube. The guy testes 2 sub-amp combos with an OEM Radio.

1st combo: an active sub

2nd combo: a passive sub with a separate amp.

The trunk of that car has that tire well which starts to deepen only at the hole, but it's not that hollow like mine is, mine is 10cm deeper and then it deepens even more for the spare tire to fit.

 

So as the guy tests the 1st combo with the active sub, everything is nice. Then tries the other combo and his face is exactly like my face lol. The video has CC subtitles too, what he concludes with the 2nd combo ist that bass is overemphasizing.

Link to video: https://www.youtube.com/watch?v=TFpfAfIofOY skip to the 24 Minute to see his face. He didn't explain why it sounded like that with the second combo. He just stated that the power of that Mosconi Pico amp is somehow not compatible with that sub...

I have a oem spare tire space under my current box with no ill effect... you do not lose pressure due to that space since it doesn't just leak out of there through a hole. 

 

The video you mention shows that tiny prefab box with two equally shallow mounted subs, all spells disaster for sound quality or spl. You are running a subwoofer at 4 ohms nominal, when it is playing it will easily go beyond that maybe into the 6-8ohms. Buy an amp that can deliver rated power at 4 ohm or wire at 2 or 1 ohm with an amp that can handle that impedance. 

 

Have you tried moving the subwoofer box to face the port and subwoofer upwards (towards the roof)?

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About that box with those subs why do they spell disaster, was that the aim of its designers? Why does it sound so badin comparison to the other sub box? I think I know what you are trying to explain, you are trying to explain the Impedance vs. the DC Resistance. But that still doesn't explain why it's sounding bad. The tire well in that video is not that hollow or deep like mine. On my car, once I take the plastic cover from the trunk, I can see the tire well, but cannot access it fully yet, it's starting to deepen itself 10-15cm down from the base height of the plastic cover and only then the tire well starts to deepen. If I want to access the tire wells bare metal, I need to first take the plastic cover out, then disassemble another plastic rectangular piece which surrounds the main plastic cover, and only then. So just imagine that under that plastic cover there is a lot of space, like roughly 60litres or more.

 

Yes sir I did that too, I played with the position and firing with NO improvements. I am going to disassemble the whole trunk and leave just bare metal. It will not be just bare metal because I have dynamat all over the tire well and trunk area and see if that makes a difference, with only the sub in that place.

If it's not the trunk area then what is it? The new sub is perfect in a perfect box, the amp and radio are not cheapos, as well as the radio, what is it? If I could just get my hands on an o scope and test the output of the amp, to be 100% sure it has a clean wave. I tested the signal already by changing the amp and the radio and things were the same. But just to make sure an O scope would be the best.

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Your spare tire well has nothing to do with this you're talking about what cubic foot of space?

 

I really think it's something you're really over looking or some incorrect husbandry of your system

 

too bad you aren't stateside local to me I would not mind trying to figure out what's wrong with your set-up

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That area under the carpet is roughly 2 cubic feet maybe more. I am sorry after recalculating it it's maybe closer to 4 cubic feet, unlike I stated in the pic, it's pretty big basically.

 

I also really want to think what you're thinking, I wish this so hard.

 

If I had one of you guys near and I knew you have heart for fellow bass heads, I would have payed you at least 200 euros just to diagnose and tell what is going on. Just tell me like:" ok so this was it..."

 

Bass output is ok as long as that goddamn box is not located in the trunk. On the back seat seems fine.

 

I am going to disassemble and take out the trunk cover and the other separated panels and leave the whole trunk empty with the spare tire well place in sight. Gonna give it a test.

 

Another thing I am going to do since I have so many subs. The newest sub is a 10 inch 2x2 Ohm and the other I wanna hook up just to mess around is the jl 12w3v3 1x4 Ohm. Gonna hook them both to the JL amp see if that makes any difference.

 

Aaron the way you are seeing it is as if somehow the signal is being distorted straight from either the amp or the HU. Isn't this what you're thinking? Because I have already eliminated that possibility. Also if an amp has a clip indicator on it and at the same time the amp is putting out a distorted signal no matter the power reproduced, does its CLIP indicator light up in that situation too? Like you could have the clip indicator which I do on my Jl amp, you could have it also as a sign telling you the amp is not working good?

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Video of disassembled trunk https://www.youtube.com/watch?v=_udVX2JjOpo

Video of the best sub location with satisfying bass output no cancellations https://www.youtube.com/watch?v=iLMICWKFl8Y

 

In the video I have Front HPF 100Hz 12db, I found better settings meanwhile, Front HPF 63Hz 12db. Those door speaker are not cheapos, at higher volume they generate quite some pressure in the legs feel them vibrating.

 

Once I move the sub in the trunk everything shatters to pieces. It sounds so horrific when it's in the trunk lol. Let me make this clear again. Once I move it to the trunk, it sounds extremely disturbing like distortion amplified, this NO MATTER THE SETTINGS, you go change phases slopes points eeverything is the same, it is a one note bass generated more or less depending on freq, very weird... I might seal that gap in the future with some mdf plates somehow to make the trunk area similar to that of Peugeot 206. I didn't know the car played such a crucial role in bass rendering. I think it was pure luck in the beginning.

 

If you watch the second video, even the camera mic doesn't distort very much the sound it makes is almost similar without distortion, for what comes to my ears in comparison to the audio of the video. So maybe you could judge a little bit if that bass note is clean or not.

 

Anyway if you take from your time to watch the videos would mean a lot to me, maybe someway somehow you have another view on this. Thank you all who have replied and taken their time. Thank a you

 

PS: Still breaking in the sub so no excessive power was introduced to it

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So these are the results. Sub on back seat OK. Sub back in the trunk not OK.

 

If the reason is not the cars acoustics, then why is this happening? You're telling me I still have muddy sloppy bass all the time, only when the sub is on the back seat it masks the impression of a clean output or what?

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