[Avetiso]

Hey everyone,

I tried searching honestly for a good 2 hours but couldn't find the information I was looking for.

I am upgrading the HiFi system in my sedan to an X2 1100.5, and I will be adding a subwoofer in the rear of the car. I will also be removing the rear deck speakers and there is almost never anyone in the rear of the car and I'm not looking to get into complicated DSP tuning for rear fill... I just know myself to know that my motivation will burn out before I get there.

So I want to use the underseat woofers as midbass's. Ideally, I was going to find a set of the Kicker SSMB8's, but I can't find them anywhere. I want to avoid the SWS-8's for this reason as well, as many people have complained that they are weak as midbass speakers.

Are there any modern and easily available speakers that people know fit into the HiFi enclosure under the seat, where I can also find or make any necessary spacers relatively easily?

Perhaps I'm wrong to desire this, but I was hoping to get 4 ohm speakers all around, and many of the drop in replacements are 2 ohm. This amp does 150w per channel and 500w on the sub channel.

If there are no good, modern options that are *not* designed as replacement speakers specifically for BMW (hard to believe, but maybe), which of the commonly suggested drop-in replacements would excel as midbass at 4ohm?

I was initially leaning towards MB Quart, but I have heard that they suffer quality issues lately. The other option I considered was Jenhert, but they seem out of stock and they are about $200 (plus VAT and shipping, I assume) which seems a little pricey when options like the Kicker SSMB8 used to exist.

I'm planning on pairing these with Alpine S2-S40C for the doors, and the sub is a 10" Arc Audio with just a regular box, no molded enclosures or anything.

tl;dr Are there modern options that are similar to the Kicker SSMB8 that are not the SWS-8 series, fit the HiFi enclosure, work good as midbasses, and are freely available? Bonus if it's 4ohm (but I may just need educating on whether or not trying to get everything to match 4ohm is worth doing).

Thanks!

[Peter Morrin]

I am in a similar situation to you. My research suggests there are a number of 8" drivers that can be made to fit the underseat enclosures, but the enclosure configuration itself is what is limiting the mid-base performance.

The concensus seems to be to cut out the sheet metal below the speakers and vent them into the cavity between the plastic under-belly tray and the sheetmetal floor. This allows the speakers to run as infinite-baffle and apparently improves their performance. There is debate about how much road noise is allowed into the cabin using this technique, concern about the amount of moisture in the cavity space, and a general concern about cutting through the steel floor of the car.

It seems that the underseat location is only good for the frequency range of 80-200 Hz. Some say only 80-150 Hz. Base-heads would want a sub-woofer for the lower frequencies and there is concern that the range between the under-seat drivers and the 4" mid-ranges in the doors is too great. You would want to get a feel to how your 4" mids perform at 150 Hz.

I am still doing my research, so please post what you find out.

[ctuna]

For the underseats.
Jehnert XE 200's if you can find them.
Audiotec Fisher Match series cheaper .
I would worry more about the quality of your amp or amp/dsp than the
ohms of the speakers.
Many other companys make BMW drop in's now .
https://mosconi-america.com/?s=bmw

Yeah it's hard to get around the gap between 4 inch and 8 inch speakers.
Even with DSP.

Do you want Hi Fidelity mid range or do you just want your car to fart?

[Avetiso]

Originally Posted by Peter Morrin

I am still doing my research, so please post what you find out.

I ended up going with an MB Quart set for the woofers under my seat. They are just branded differently as HiFonics, but it's the same speaker.

I couldn't find anything else. Jenherts were sold out everywhere I looked. So were Rainbows. I was going with a full sub setup in the back so the SWS weren't relevant to me.

If I could do it over again I'd probably save the money and just get the Vibe Optisound off ebay. You can get the two underseats for $200 shipped to the US from the UK. I don't believe that the difference between the underseat subs is all that important in the grand scheme of this, especially if you have subs to provide most of the bass.

Second choice would have been Gladens, but I really don't think I'd notice anything between the options, anyway, and I didn't want to go through analysis paralysis.

[Avetiso]

Originally Posted by ctuna

For the underseats.
Jehnert XE 200's if you can find them.
Audiotec Fisher Match series cheaper .
I would worry more about the quality of your amp or amp/dsp than the
ohms of the speakers.
Many other companys make BMW drop in's now .
https://mosconi-america.com/?s=bmw

Yeah it's hard to get around the gap between 4 inch and 8 inch speakers.
Even with DSP.

Do you want Hi Fidelity mid range or do you just want your car to fart?

I couldn't find Jenherts anywhere. The Jenhert website says out of stock, and that one shop in New Jersey that people mentioned a few times is out of them, too. They said they don't know if they'll ever get more stock.

Many of the BMW speakers mentioned on the forums over the years aren't available anywhere, otherwise I'd have gone with a full rainbow set a long time ago.

My car farts between gears all the time.

[Onizukachan]

You don’t want midrange reproduction form under the seat anyway, just 80 on down, so apologies if I don’t get why people are so against the SWS which pair nicely with the factory midranges amd take over with authority right about where those lose it at about 90hz. You have to overlap the xover by some 10hz or so but nothing major. Iirc iwas at about 83 hp mids, 90 low pass SWS with a 36 db octave xover on mids and 30 db oct on subs.

[Runnin'Rich]

I’m in the same boat as OP

Thanks for mentioning the Vibe speakers, I’m going on a trip to the UK soon so could be an option.

I too have wanted to buy Jehnerts XE200 for a while.

I already upgraded my Hi-Fi system to EPS speakers with PP86DSP amp, except the subs are still HIfi. Pretty disappointed with how basic it sounds to be honest. Hopefully replacing the subs will bring everything together so I don’t regret the money I’ve already invested.

How about EPS subs or logic 7’s? Maybe they are equivalent to the vibes?

[brooks1005]

People are going to laugh but these work great. I have the s677 pkg on my e92 and wanted to upgrade. A certain US company seems to be selling this exact woofer on their site. I am also using this brands 4in and 4.5in speakers. Both have made a huge difference in sounds and clarity.
https://www.aliexpress.us/item/32568...2usa4itemAdapt

Another is LQ Audio which is another brand that a US vendor has relabeled for themselves.

[Avetiso]

Originally Posted by Onizukachan

You don’t want midrange reproduction form under the seat anyway, just 80 on down, so apologies if I don’t get why people are so against the SWS which pair nicely with the factory midranges amd take over with authority right about where those lose it at about 90hz. You have to overlap the xover by some 10hz or so but nothing major. Iirc iwas at about 83 hp mids, 90 low pass SWS with a 36 db octave xover on mids and 30 db oct on subs.

I'm actually running my underseats from about 90hz to 200hz and handing off to mid 4" CDT CL-42s at 200hz, and I'm pretty happy with how it sounds. I have 2 10" subs in the trunk, so I don't use my underseats in the same range as the subs. I quite enjoy the sound at the moment. I make small adjustments here and there over time and I think I'm getting things blending pretty well.

I'll admit I believed a lot of the bad press about the SWS-8. I ended up going with an MB Quart analog (HiFonics, same speaker, though) for the underseats. Overall pretty happy. They do the most work when playing drums in rock songs.

[Avetiso]

Originally Posted by Runnin'Rich

I’m in the same boat as OP

Thanks for mentioning the Vibe speakers, I’m going on a trip to the UK soon so could be an option.

I too have wanted to buy Jehnerts XE200 for a while.

I already upgraded my Hi-Fi system to EPS speakers with PP86DSP amp, except the subs are still HIfi. Pretty disappointed with how basic it sounds to be honest. Hopefully replacing the subs will bring everything together so I don’t regret the money I’ve already invested.

How about EPS subs or logic 7’s? Maybe they are equivalent to the vibes?

I have a friend that has an individual audio setup in his E93 M3, and while it's definitely great on clarity, I'm overall not a huge fan of how it sounds relative to the price of the speakers. I decided early on that I was going to prefer aftermarket speakers for the money before I even started buying anything.

The MB Quart analogs I have under the seat sound pretty good. They get muddy when you try to push them (in my opinion), but I'm happy with them playing between 90 and 200 hz (plus whatever slope they have on either side, my amp is a 12db/octave).

[Avetiso]

Originally Posted by brooks1005

People are going to laugh but these work great. I have the s677 pkg on my e92 and wanted to upgrade. A certain US company seems to be selling this exact woofer on their site. I am also using this brands 4in and 4.5in speakers. Both have made a huge difference in sounds and clarity.
https://www.aliexpress.us/item/32568...2usa4itemAdapt

Another is LQ Audio which is another brand that a US vendor has relabeled for themselves.

Dang, those do look just like the Ghosts, I believe. I'd be curious to see a side-by-side and see if they are in fact the exact same speaker or if they just copied the grill.