Under-Seat Subwoofer Issues

This thread is going in circles.

HK and KIA stated that they did not want to take up boot / trunk space with a full size sub. So the solution was to split it into two smaller subs and mount them under the seats.
The aim was to improve low frequency sound to enhance the bass coming from the doors. Very low frequency sounds in hi-fi are designed to be non-directional, so if set up correctly you should not be able to discern where the sound is coming from - in this case under your seat.
If you want to prove the subs are working do the dollar test - they certainly are working.

Most bass sound that you hear will come from the mid and bass woofers in the doors, these are the frequencies your ears are more attuned to.
For me there is more than adequate bass in the system, +4 shakes the car just nicely!

If you want more bass in your music then you probably need larger woofers not necessarily a bigger sub.
The HK is a great system but obviously not to everyone’s taste.
 
I took delivery of Kia stinger gt 2020, two weeks now. I tested the sub using low frequency sound recording used for testing home theatre sub. The function of a sub is to play low frequency audio and you should feel the thump. I did the same paper test to see if they are actually wired. Yes they are wired and makes the paper move. But any speaker will do that. This does mean it is functioning as a sub. In my car, all the base is coming from the large speakers at bottom of the door and it is boomy and defining even at low volume with base set to 0. I have booked it in for this to be rectified, as I have doubt that the woofers are not behaving as Subs. I have also noted that switching between comfort mode and sports mode does not change the Bimodal exhaust notes. It sounds the same. The demo in a show room, changed the exhaust notes when switching between comfort and sports mode. I am very disappointed with KIA. There is no quality control by KIA to make sure dealerships are doing all the checks and balances before you take delivery of your vehicle. It ruins the whole experience of getting in and driving your new ride.
 
I have also noted that switching between comfort mode and sports mode does not change the Bimodal exhaust notes. It sounds the same. The demo in a show room, changed the exhaust notes when switching between comfort and sports mode. I am very disappointed with KIA. There is no quality control by KIA to make sure dealerships are doing all the checks and balances before you take delivery of your vehicle. It ruins the whole experience of getting in and driving your new ride.

This is correct, there is no difference between Comfort and Sports mode. The demo could not have had an OEM bi-modal system.
 
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By far the best audio quality is obtained directly from the Samsung Galaxy regardless if it's outputed via BT/AUX/USB.
Out of curiosity I tried android auto for the first time & the same audio file playing via android auto was terribly muffled.
The quality was unacceptable - So I ended up removing android auto from my phone since I didn't find anything particularly useful from it.
 
I took delivery of Kia stinger gt 2020, two weeks now. I tested the sub using low frequency sound recording used for testing home theatre sub. The function of a sub is to play low frequency audio and you should feel the thump. I did the same paper test to see if they are actually wired. Yes they are wired and makes the paper move. But any speaker will do that. This does mean it is functioning as a sub. In my car, all the base is coming from the large speakers at bottom of the door and it is boomy and defining even at low volume with base set to 0. I have booked it in for this to be rectified, as I have doubt that the woofers are not behaving as Subs. I have also noted that switching between comfort mode and sports mode does not change the Bimodal exhaust notes. It sounds the same. The demo in a show room, changed the exhaust notes when switching between comfort and sports mode. I am very disappointed with KIA. There is no quality control by KIA to make sure dealerships are doing all the checks and balances before you take delivery of your vehicle. It ruins the whole experience of getting in and driving your new ride.

Identical to my 2018. Don't get too excited about it being rectified any time too soon or think that your dealer has anything to do with it...
 
From interior to exterior to high performance - everything you need for your Stinger awaits you...
Resurrecting an old (and long) thread. Mine work but I find them to sound "flabby". I did find the video interesting where they talk about venting them to the outside-kind of reminds me of an aperiodic enclosure or infinite baffle. If I get around to it I might try a different shallow woofer in that space of (if I get really ambitious) an up front subwoofer under the glove box pushed waaaay far forward to maximize space.
 
I know this thread is old but if you want to hear/ feel the subs play this:

 
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I hope my subs wake up. 1k miles. I feel no bass. I read the thread. Imma use USB and center and set all to 0. My new stinger doesn't have the advanced menu I seen some ppl.show. ... I feel like my subs do nothing. I'll find out tomorrow with a dollar lol. No 1 ever seen if there was a setting on the amp?
 
I hope my subs wake up. 1k miles. I feel no bass. I read the thread. Imma use USB and center and set all to 0. My new stinger doesn't have the advanced menu I seen some ppl.show. ... I feel like my subs do nothing. I'll find out tomorrow with a dollar lol. No 1 ever seen if there was a setting on the amp?
I followed someone’s advice here and set the eq in Spotify to, if I remember correctly, “rock” which increased bass and treble. Now it’s like I’m in a different car.
 
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From interior to exterior to high performance - everything you need for your Stinger awaits you...
I hope my subs wake up. 1k miles. I feel no bass. I read the thread. Imma use USB and center and set all to 0. My new stinger doesn't have the advanced menu I seen some ppl.show. ... I feel like my subs do nothing. I'll find out tomorrow with a dollar lol. No 1 ever seen if there was a setting on the amp?
Are you on “On stage” surround sound mode and +8 bass or higher, +4 mid & +2 treble? If so it should be loud and vibrate all the mirrors at 8-10 volume with most lossless audio and even HD radio. Just don’t expect to feel boom from under the seats, as that’s not how this and most high end audiophile systems are designed.
 
Also, the crossover I think it set really low, so only a good source with the right frequencies will fire them. When they are firing, they work rather well for a stock sub.

^ this ... i think they are crossed over at around 40-ish Hz, which is very low. if you want to hear them, use a music app with an adjustable EQ (i use Poweramp), and boost the low freqs (31Hz, 62Hz) and you will hear/feel them.
iWqas6PeqnqDxKXj3Jy9V9S0lsdmM47k3eEf_iP6U0Ut0x8m8RbHcKP0HXU2WckE4mWr=w2560-h1440


with that being said, i listen to mostly thrash/metal that typically doesn't get that low, so the underseat subs rarely get any work for me. i do like my bass tight and accurate, so i added a powered sub in a sealed enclosure with a higher lowpass cutoff frequency, so i get the hit from a bass drum better.
 
so i added a powered sub in a sealed enclosure with a higher lowpass cutoff frequency, so i get the hit from a bass drum better.
Which one?
 
Which one?

Kicker powered sub i had in my last two cars :D

10", sealed enclosure. super easy install, especially in the Stinger with the battery in the rear ... no remote turn-on wire needed - has auto turn on, and no Line Out Converter needed - has high level inputs.

its not going to shake the neighborhood, but that's not what i wanted it for. i keep the bass level around 11 o'clock, and that works for me.

shopping
 
I hope my subs wake up. 1k miles. I feel no bass. I read the thread. Imma use USB and center and set all to 0. My new stinger doesn't have the advanced menu I seen some ppl.show. ... I feel like my subs do nothing. I'll find out tomorrow with a dollar lol. No 1 ever seen if there was a setting on the amp?
I bought a new Stinger GT in January. Next day went back to the dealership as I could hear nothing from the Under seat Sub woofers. They checked another brand new car in showroom. Same. No sound. They said they would get it checked out.

Meantime I found several posts online then did tests myself.

For the majority of music these subs do NOTHING. Subs do not emit music, only a deep base and only when a track has a very deep base frequency.

If you are interested google "I saw the light" Daryl Hall and Todd Rungren. Use a video downloader and drop that Video onto a USB and straight into the Stinger. Set the base up and you will feel the base.

To confirm drop a dollar bill or something similar onto the sub woofer under the seat, we don't have dollar bills we have dollar coins ha ha here in Oz so I used a lotto ticket.....you will see it vibrating. It proves your sub woofers are working. I am not an audio guy but the air pressure changes of the sub woofer when the amp decides there is a low enough frequency to direct it to the sub woofers will enhance the Bass coming from the door speakers.

But you will NEVER hear any music coming from sub woofers if that makes sense.....
 
From interior to exterior to high performance - everything you need for your Stinger awaits you...
I've posted this pic in other threads, but this is an input RTA for the underseat subwoofers. You can see the crossover is around 40-45hz, which is pretty deep bass, especially for a shallow ~7" speaker.

The subs do technically work, but you really don't hear them.

sub1 oem.webp
 
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Kicker powered sub i had in my last two cars :D

10", sealed enclosure. super easy install, especially in the Stinger with the battery in the rear ... no remote turn-on wire needed - has auto turn on, and no Line Out Converter needed - has high level inputs.

its not going to shake the neighborhood, but that's not what i wanted it for. i keep the bass level around 11 o'clock, and that works for me.

shopping
Cool

did you use a front door woofer channel as the input for this sub? or the sub channel?
 
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Cool

did you use a front door woofer channel as the input for this sub? or the sub channel?

pretty sure i tapped the front door speakers at the amp ... to avoid the extreme low pass filter on the factory subs.
 
Is there a diagram somewhere of the sound system from the head unit to each speaker? Sorry to hijack. It'd be nice if we could upgrade the amp, for instance, with something plug and play. Pipe dream, I'm sure. But overall the sound system needs just a bit more power in my ears.
 
Is there a diagram somewhere of the sound system from the head unit to each speaker? Sorry to hijack. It'd be nice if we could upgrade the amp, for instance, with something plug and play. Pipe dream, I'm sure. But overall the sound system needs just a bit more power in my ears.
Hello Kazz, and long time no chat. But have to admit I don’t understand what you and some others on here mean by needing more power or loudness.

Not saying it will ever be comparable to an aftermarket system with 1000s of watts & powered 10”+ subs, but with the correct settings & input, anything over volume 13-15 shakes all the mirrors and is almost deafening loud.

HK’s 720w & 15 speakers is pretty substantial for a good high end stock system and it would cost thousands more to do marginally better. I’m just betting it’s more a matter of input quality & settings vs. not enough power/volume.
 
From interior to exterior to high performance - everything you need for your Stinger awaits you...
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