[jpt99]

Originally Posted by pierreye

You can use this to tap from 12v source. Or any 12v DC regulator will do.

This?

[pierreye]

If you are not sure on the power source just use the miniDC Isolator. You can use the REM out to turn on/off your power amp. REM in is to turn ON/OFF your MiniDSP 2x4 HD.

Refer to below link for integration. Treat the stereo input in the documentation as underseat Left and Right Input. Channel One and Two for underseat Left and Right Output. Channel 3 (sum of 2 input) for Subwoofer output. Try out 70hz LR 24db/oct between your underseat sub and subwoofer first.

https://www.minidsp.com/applications...ub-integration.

[jpt99]

Originally Posted by pierreye

If you are not sure on the power source just use the miniDC Isolator. You can use the REM out to turn on/off your power amp. REM in is to turn ON/OFF your MiniDSP 2x4 HD.

Refer to below link for integration. Treat the stereo input in the documentation as underseat Left and Right Input. Channel One and Two for underseat Left and Right Output. Channel 3 (sum of 2 input) for Subwoofer output. Try out 70hz LR 24db/oct between your underseat sub and subwoofer first.

https://www.minidsp.com/applications...ub-integration.

Originally Posted by pierreye

If you are not sure on the power source just use the miniDC Isolator. You can use the REM out to turn on/off your power amp. REM in is to turn ON/OFF your MiniDSP 2x4 HD.

Refer to below link for integration. Treat the stereo input in the documentation as underseat Left and Right Input. Channel One and Two for underseat Left and Right Output. Channel 3 (sum of 2 input) for Subwoofer output. Try out 70hz LR 24db/oct between your underseat sub and subwoofer first.

https://www.minidsp.com/applications...ub-integration.

Don't understand this: Channel 3 (sum of 2 input) for Subwoofer output. But I'll research it.

Regarding the amps, the ACM has a BYPASS option, which I will use, right? The sub amp doesn't. I guess I would set the amp crossover the same as what I set on the minidsp?

[pierreye]

Originally Posted by jpt99

Don't understand this: Channel 3 (sum of 2 input) for Subwoofer output. But I'll research it.

Regarding the amps, the ACM has a BYPASS option, which I will use, right? The sub amp doesn't. I guess I would set the amp crossover the same as what I set on the minidsp?

Do not set the amp crossover similar to minidsp. If you do this, it will stack the low pass filter. Do a bypass in the amp crossover and only use miniDSP digital crossover. I would suggest try to research how to integrate multiple drivers using crossover, EQ and delay. The goal is smooth transition from multiple drivers. For example, mid bass driver for underseat sub covering 70hz to 180hz and sub bass driver from 20hz to 70hz. The slope will determine how steep you want to transition from each driver. The nearer your crossover to limit of the lower freq of your driver, the steeper you need to set the filter (in terms of higher order, you will see option like 12db/oct which is 2nd order and 24db/oct which is 4th order). Since this is lower frequency we don't have to worry about speakers off axis response pattern.

[jpt99]

Originally Posted by pierreye

Do not set the amp crossover similar to minidsp. If you do this, it will stack the low pass filter. Do a bypass in the amp crossover and only use miniDSP digital crossover. I would suggest try to research how to integrate multiple drivers using crossover, EQ and delay. The goal is smooth transition from multiple drivers. For example, mid bass driver for underseat sub covering 70hz to 180hz and sub bass driver from 20hz to 70hz. The slope will determine how steep you want to transition from each driver. The nearer your crossover to limit of the lower freq of your driver, the steeper you need to set the filter (in terms of higher order, you will see option like 12db/oct which is 2nd order and 24db/oct which is 4th order). Since this is lower frequency we don't have to worry about speakers off axis response pattern.

Originally Posted by pierreye

Do not set the amp crossover similar to minidsp. If you do this, it will stack the low pass filter. Do a bypass in the amp crossover and only use miniDSP digital crossover. I would suggest try to research how to integrate multiple drivers using crossover, EQ and delay. The goal is smooth transition from multiple drivers. For example, mid bass driver for underseat sub covering 70hz to 180hz and sub bass driver from 20hz to 70hz. The slope will determine how steep you want to transition from each driver. The nearer your crossover to limit of the lower freq of your driver, the steeper you need to set the filter (in terms of higher order, you will see option like 12db/oct which is 2nd order and 24db/oct which is 4th order). Since this is lower frequency we don't have to worry about speakers off axis response pattern.

Been doing more research, and am contemplating whether to remove everything and install an UP7 amp with my Mobridge DA-1. The UP7 contains all the features of my current set-up plus additional power to the front/rear doors. It would be an all-in-one system, besides the trunk sub/amp. Plus the AF DSP software is quite user friendly. I would have to confirm whether the harness from my previous Match 82DSP is compatible with the UP7. It looks like it might be. Thoughts?

[pierreye]

No experience with Mobridge DA-1 but looks like workable. You will need to disconnect 2 rear channels behind the seat which doesn't really matter for 2 channel music. It does simplify the setup.

Here's the link someone doing exactly what you have in mind.

https://www.2addicts.com/forums/show...8&postcount=36

[damack]

Looks like Audiofrog will make a shallow 8" sub soon. I'm not sure what the fancy numbers mean but I know some of you do. Thoughts?

[Billfitz]

It has lower sensitivity than the stock hi-fi woofer, so if you were to do a simple driver swap it wouldn't be as loud, requiring around 110w to equal the output of the stock woofer at 50w. If separately amplified its 250w power rating and 10mm excursion capability would allow it to go louder than the stock woofer.

[GeorgeR]

Originally Posted by damack

Looks like Audiofrog will make a shallow 8" sub soon. I'm not sure what the fancy numbers mean but I know some of you do. Thoughts?

AudioFrog makes excellent drivers and I assume this will be well received. As part of the GS line hopefully it will be affordable as well. It is not nearly as shallow as some of the other top premium options; not sure if it would fit and if you tried, it would take a lot of customization.

Other Car Audio forums lean towards the Audio Development W800neo, Illusion Audio C8-W, and Focal Utopia 8WM for under seat woofers in BMW's. It should go without saying, those installing these woofers are also adding powerful aftermarket amplifiers and high end DSP's. Most will also have a sub-woofer.

[Soul_Glo]

Spent over an hour reading this thread from start to finish. How interesting is my life? I have HK but want a bit more lows. I considered swapping out the under seats for SWS and adding a separate amp. At the end of the thread I decided to keep my trunk sub and shift it to my G20. I need a custom box though. I find the JL w6 12" heavy so will go for a JL 6w3v3 (4 ohm). It's tight, punchy and, throws like a 10"

Underseats is still very tempting. Technic never got back to me about the harness despite buying three off him in the past.

[Virginijus]

Hey, Guys.

Have just read full thread and still have few questions.

I have F30 LCI with base audio - no tweeters and no separate AMP.

I want to make an upgrade to have a proper sound quality and almost all comparisons are Hi-fi or HK to something at OEM side. In my case I have base system.

So to my knowledge AMP is main upgrade in Hi-fi and HK systems, so in my case it is absolutely necessary. So 3 steps of what I see at this point:
1. I try to get only AMP with DSP installed and see how the base drivers work from there.
2. Add 2 way system in front door.
3. Add under seat subs.

Let me know your opinion how many steps I should start with as I am not going to do installation myself, so the price differs if I choose to do upgrade in one or two steps.

Additional question is has anyone heard of these (Zapco made): https://www.esbcar.com/bmw-sub-1

Thanks for the answers!

[Encanto]

- Replace all OEM speakers with aftermarket -front component set, rear coaxials, 8" woofers.
- add aftermarket amp+DSP - Match UP 7DSP, Helix P SIX DSP MK2, JL Audio VX600/6i, Mosconi One 70.6 for example.

Replacing all OEM speakers is a must when adding an aftermarket amp+DSP, IMO. They just not sound any better with more power.

Originally Posted by Virginijus

Hey, Guys.

Have just read full thread and still have few questions.

I have F30 LCI with base audio - no tweeters and no separate AMP.

I want to make an upgrade to have a proper sound quality and almost all comparisons are Hi-fi or HK to something at OEM side. In my case I have base system.

So to my knowledge AMP is main upgrade in Hi-fi and HK systems, so in my case it is absolutely necessary. So 3 steps of what I see at this point:
1. I try to get only AMP with DSP installed and see how the base drivers work from there.
2. Add 2 way system in front door.
3. Add under seat subs.

Let me know your opinion how many steps I should start with as I am not going to do installation myself, so the price differs if I choose to do upgrade in one or two steps.

Additional question is has anyone heard of these (Zapco made): https://www.esbcar.com/bmw-sub-1

Thanks for the answers!

[SD Convert]

Originally Posted by Encanto

- Replace all OEM speakers with aftermarket -front component set, rear coaxials, 8" woofers.
- add aftermarket amp+DSP - Match UP 7DSP, Helix P SIX DSP MK2, JL Audio VX600/6i, Mosconi One 70.6 for example.

A few items to add here for the budget conscious:

• The HiFi drivers are fairly good, without the sticker-shock I would expect from BMW. For the HiFi system, the door mid-bass drivers (65-13-9-264-944) are $62.63 and the tweeter (65-13-9-220-750) is $43.84. (EDIT: @Billfitz lists some other good options below)
• I believe the base package has a 6.5" "sub". To go to the 8" sub, you'll probably need new under-seat sub boxes. I don't know if these are sold separately from the sub. The HiFi sub price is $252 per side at GetBMWParts.com (65-13-9-210-149 and 65-13-9-210-150), and the picture appears to have the box as part of it. This will probably end up requiring a call/trip to the dealer to figure out. If you've already got the 8" subs, this won't be a problem.
• If you're on a tight budget, a used HiFi amp should be able to tide you over with the HiFi drivers until you can find the $1K to upgrade it. Only go with stock HiFi subs with this, as the other subs will probably sound worse, either by being inferior or by needing more power.
• Good luck with the wiring. This is close to what you'd need, but you should verify with the vendor (they're responsive) that it will work with the HiFi amp.

[Encanto]

OP has base (Stereo) system, not HiFi.

Originally Posted by SD Convert

A few items to add here for the budget conscious:

• The HiFi drivers are fairly good, without the sticker-shock that I would expect from BMW. For the HiFi system, the door mid-bass drivers (65-13-9-264-944) are $62.63 and the tweeter (65-13-9-220-750) is $43.84.
• I believe the base package has a 6.5" "sub". To go to the 8" sub, you'll probably need new under-seat sub boxes. I don't know if these are sold separately from the sub. The HiFi sub price is $252 per side at GetBMWParts.com (65-13-9-210-149 and 65-13-9-210-150), and the picture appears to have the box as part of it. This will probably end up requiring a call/trip to the dealer to figure out. If you've already got the 8" subs, this won't be a problem.
• If you're on a tight budget, a used HiFi amp should be able to tide you over with the HiFi drivers until you can find the $1K to upgrade it. Only go with stock HiFi subs with this, as the other subs will probably sound worse, either by being inferior or by needing more power.
• Good luck with the wiring. This is close to what you'd need, but you should verify with the vendor (they're responsive) that it will work with the HiFi amp.

[SD Convert]

Originally Posted by Encanto

OP has base (Stereo) system, not HiFi.

Understood. That's why I provided information to upgrade to HiFi, instead of going full-aftermarket. There's a HUGE price savings and it's also a nice quality bump compared to the base.

[Billfitz]

I wouldn't buy OEM drivers except at used prices. While they are very good they're not deserving of the price they go for. These are just as good, and the price is right:
https://www.parts-express.com/4-glas...odels--292-490
https://www.parts-express.com/1-tita...odels--292-498

Note that the prices are for a pair.

[SD Convert]

Originally Posted by Billfitz

I ditched the cheap capacitor on mine, and went to third order filtering at 4kHz, which made them run much cleaner. I also added second order low pass filters to the midbasses. The stock arrangement had none.

Is there any chance that you could post a schematic or connection list for this crossover? Keeping the mids out of the tweeter is likely to help the overall sound. It should also be an inexpensive upgrade.

Win-Win - We need more of these

[Encanto]

Originally Posted by SD Convert

Understood. That's why I provided information to upgrade to HiFi, instead of going full-aftermarket. There's a HUGE price savings and it's also a nice quality bump compared to the base.

There is no upgrade to HiFi without a complete OEM HiFi harness. There is no “huge” savings, and the work to retrofit just the OEM harness is not worth the sound quality improvement.

[Billfitz]

The original OEM setup doesn’t have crossovers between the midranges and tweeters. It only has a cheap capacitor that keeps the midrange out of the tweeters. It doesn’t do a very good job of it, leading to distortion. There’s no filtering on the midranges to keep the high frequencies out of them, so literally a quarter of the high frequencies are lost going to the midranges that can't reproduce them.

This third order high pass filter is sixteen times more effective than a single capacitor in blocking midrange from the tweeters.



The low pass filter is second order. By using a third order high pass with a second order low pass polarity issues are avoided.



These are the parts:

8.2uf cap: https://www.parts-express.com/dayton...citor--027-426

20uF cap: https://www.parts-express.com/dayton...citor--027-436

0.1mH coil: https://www.parts-express.com/dayton...-coil--257-020

0.2mH coil: https://www.parts-express.com/dayton...-coil--257-024

These filters tap into the wiring to the drivers. The tweeters normally plug into the midranges, so you have to create a ‘Y’ in the wire leading to each midrange. One leg of the wire goes to the low pass filter and then to the midrange, the other goes to the high pass filter and then to the tweeter. The capacitor on the factory wire between the midrange and tweeter is discarded. The components can be hot melt glued and plastic zip tied to perf boards for placement in the doors.
https://www.parts-express.com/red-pe...5-x-5--260-180

[SD Convert]

Originally Posted by Billfitz

This third order high pass filter is sixteen times more effective than a single capacitor in blocking midrange from the tweeters.

https://billfitzmaurice.info/images/...z highpass.jpg

Would it be useful to bypass the metalized poly caps in the high-pass with a small (0.01uF) film & foil cap? My recollection is that the film & foil caps have a much lower ESR than metalized poly caps, due to construction materials and methods. This might make a few dB difference in the top octave, and it's cheap ($2 per crossover).

[Billfitz]

That technique is sometimes used with high value non-polarized electrolytics, and what's used to bypass the NPE is a poly.

[RocketBoots]

Originally Posted by Billfitz

The original OEM setup doesn’t have crossovers between the midranges and tweeters. It only has a cheap capacitor that keeps the midrange out of the tweeters. It doesn’t do a very good job of it, leading to distortion. There’s no filtering on the midranges to keep the high frequencies out of them, so literally a quarter of the high frequencies are lost going to the midranges that can't reproduce them.

This third order high pass filter is sixteen times more effective than a single capacitor in blocking midrange from the tweeters.

https://billfitzmaurice.info/images/...z highpass.jpg

The low pass filter is second order. By using a third order high pass with a second order low pass polarity issues are avoided.

https://billfitzmaurice.info/images/BMW/Low pass.jpg

These are the parts:

8.2uf cap: https://www.parts-express.com/dayton...citor--027-426

20uF cap: https://www.parts-express.com/dayton...citor--027-436

0.1mH coil: https://www.parts-express.com/dayton...-coil--257-020

0.2mH coil: https://www.parts-express.com/dayton...-coil--257-024

These filters tap into the wiring to the drivers. The tweeters normally plug into the midranges, so you have to create a ‘Y’ in the wire leading to each midrange. One leg of the wire goes to the low pass filter and then to the midrange, the other goes to the high pass filter and then to the tweeter. The capacitor on the factory wire between the midrange and tweeter is discarded. The components can be hot melt glued and plastic zip tied to perf boards for placement in the doors.
https://www.parts-express.com/red-pe...5-x-5--260-180

Did you measure the mid and tweeter to arrive at your design? If not, how did you determine what value caps and coils to use?