[joehoe]

I've been doing research on upgrading my F30 with HiFi (base) audio, and need some advice on which path would be best. I am trying to keep it in a budget, no more than $750. I agree with some of the other forum members that the stock speakers sound decent, but the under seat woofers are the main weak point for me. At higher volumes, I can hear the woofers begin to distort (Can anyone tell me if that's the woofers distorting or is it the amp clipping?)

It has come down to two upgrade paths for me:
1) Buying a used Bimmertech amp, seeing how the sound improves with the mids/highs and the under seat woofers. If the woofers still don't sound good, then replacing with Earthquake SWS's.
2) I have an Alpine MRV-m500 amp laying around, buying some Earthquake SWS 8's, installing that all together, and hopefully calling it a day if the set up sounds good to me.

My questions are for set up #1, will I notice a large improvement in clarity of the stock low/mids/highs? Also, will the Bimmertech amp push enough power to the woofers? The amp only pushes out 70 watts RMS/140 max, and I've read that the SWS woofers need 150 RMS to really notice an improvement.

Question for set up #2 if for the people that have gone this route, how does it sound in your experience?

I've also considered using the Alpine MRV-m500, buying a stealth box from visual ice, and installing a trunk sub. However, I feel that I would still hear the underseat woofers distort at higher volumes.

Any thoughts or suggestions are appreciated, TYIA

[Billfitz]

The Earthquake is one of the very few woofers that will actually outperform the stock under seat woofers, but it needs power to do it, preferably 150 watts each. A separate amp would be best. As for clarity, that's not a sonic characteristic below 150Hz, so it's a non-issue.

[Wgosma]

Re: #1- amp greatly improved sound quality/definition with hi-fi speakers, good upgrade. Did this with used older 82DSP BimmerTech amp and was very satisfied. Being able to 'tune' the amps profile is really great feature; speaker time alignment makes a real impact, tuning by ear using the Audiotech-Fischer software is pretty easy and quite effective. (Car is 2012 X3; got an X3 specific tune file from BimmerTech, did some tweaking of it as mentioned).

Sub upgrade you've mentioned makes sense- the real lows are what is missing w/stock.

The $500 I paid for that BimmerTech amp; was more than worth it- limited budget....do the amp only and you will be very pleased.

Good luck/Bill

[eleven11]

I'd upgrade the amplifier first.

Considerations:

1. JL Audio XD600/6v2 ($600 MSRP) + Technic Harness ($90 MSRP)
   
   
2. Audiotech Fischer MATCH UP 7BMW Amp/DSP ($1000 MSRP, sub-$750 on eBay new). Unlike the Bimmertech Amp (PP86DSP), this pushes more power to the sub channels.
   

Of course, there's a used market for both of these options.

[joehoe]

Thanks for the input guys

Originally Posted by eleven11

I'd upgrade the amplifier first.

Considerations:

1. JL Audio XD600/6v2 ($600 MSRP) + Technic Harness ($90 MSRP)
   
   
2. Audiotech Fischer MATCH UP 7BMW Amp/DSP ($1000 MSRP, sub-$750 on eBay new). Unlike the Bimmertech Amp (PP86DSP), this pushes more power to the sub channels.
   

Of course, there's a used market for both of these options.

Good to know the JL audio and technic harness is an options, thanks.

[Wgosma]

...speaking of these Earthquake SWS subs - I'm reading a comment here and there that installation (in place of stock under seat subs) my require modification of the 'enclosure' - any input on that? (car is an F25 X3).

Thanks/Bill

[joehoe]

Originally Posted by Wgosma

...speaking of these Earthquake SWS subs - I'm reading a comment here and there that installation (in place of stock under seat subs) my require modification of the 'enclosure' - any input on that? (car is an F25 X3).

Thanks/Bill

One post on the forums showing the install had the member shaving down a small part of the inside of the enclosure. I also saw a member selling some Earthquakes in the classifieds that came with spacers, so I am assuming those were so that you didn't have to shave anything down? Not 100% sure on this info though, hope someone else can chime in.

[W211F30]

OP: I just completed audio drop-in upgrade and couldn't be happier..

I started out with BimmerTech amp pp82 (used), bought it from a fellow forum member.
But the woofers were a bit weak, so I bought the earthquake sws (new), and the sound quality has improved. I didn't stop there tho... bought a used bavsound stage 1 from another forum member, and the sound quality is superb!

[joehoe]

Originally Posted by W211F30

OP: I just completed audio drop-in upgrade and couldn't be happier..

I started out with BimmerTech amp pp82 (used), bought it from a fellow forum member.
But the woofers were a bit weak, so I bought the earthquake sws (new), and the sound quality has improved. I didn't stop there tho... bought a used bavsound stage 1 from another forum member, and the sound quality is superb!

Thanks for the info! So far I am actually on the same upgrade path as you right now. I purchased a used BimmerTech amp PP82, and installed that yesterday. Hopefully I can find someone selling some undreseat subs, if not I'll buy them new like you.

Question, I've read and also Billfitz above says the Earthquakes need about 150 RMS to sound good. How do they sound with the Bimmertech amp to you?

I'm going to try the Stock hi-fi speakers for a while, and only upgrade those if i find an absolute need to. (Or find a really good deal on the forums )

[Wgosma]

Originally Posted by joehoe

Thanks for the info! So far I am actually on the same upgrade path as you right now. I purchased a used BimmerTech amp PP82, and installed that yesterday. Hopefully I can find someone selling some undreseat subs, if not I'll buy them new like you.

Question, I've read and also Billfitz above says the Earthquakes need about 150 RMS to sound good. How do they sound with the Bimmertech amp to you?

I'm going to try the Stock hi-fi speakers for a while, and only upgrade those if i find an absolute need to. (Or find a really good deal on the forums )

Continuing to follow this thread...I'm interested also to hear how well the Earthquakes perform w/o external amp. I'm running 82DSP unit in 2012 X3, standard hi-fi speakers - sounds very good but bass is lacking.
Thanks/Bill

[Billfitz]

Originally Posted by joehoe

Question, I've read and also Billfitz above says the Earthquakes need about 150 RMS to sound good.

They don't need that much to sound good, they need that much to reach full output. In order to go lower than the stock driver they have to give up sensitivity, ie., how loud they'll go with a given input voltage. That lower sensitivity can be made up for with power, and they have the necessary excursion to handle that power. If they go loud enough for you without 150w each all well and good.
The trade off between enclosure size, low frequency response and sensitivity is defined by Hoffman's Iron Law: http://www.salksound.com/wp/?p=56
Hoffman's Iron Law is one of the reasons why most claims of getting much better results with a replacement driver alone are advertising hooey.

[W211F30]

Originally Posted by joehoe

Thanks for the info! So far I am actually on the same upgrade path as you right now. I purchased a used BimmerTech amp PP82, and installed that yesterday. Hopefully I can find someone selling some undreseat subs, if not I'll buy them new like you.

Question, I've read and also Billfitz above says the Earthquakes need about 150 RMS to sound good. How do they sound with the Bimmertech amp to you?

I'm going to try the Stock hi-fi speakers for a while, and only upgrade those if i find an absolute need to. (Or find a really good deal on the forums )

BimmerTech PP82 and EQ-SWS combo is a good combo, but you may need to tune it with AudioTech.. But then again sound quality is subjective.

[HansC.]

I just did a major overhaul of the base stereo in my 340i (2019 F31) I went with Focal fronts, rears and woofers; all driven by the relatively new Alpine PDP-E800DSP (8×100W) configured to drive the woofers in parallel mode so, in effect, 4×100W for the doors+2×200W for the woofers. I don't see/hear a need for more low end and punch is amazing.

I coded my HU EVO to hifi line out and ran the line outs directly to the amp in effect bypassing the ASD. I then coded the ASD to HIFI and ran the ASD output as input 5 on the amp thereby allowing me to configure ASD levels from Alpine’s DSP tool – pretty neat

The Alpine amp fits perfectly in the rear left well.

After some hours of DSP tuning I became very very happy with the result.

I know that the above is above your budget but I bring it up as an alternative to the proposals you will more or less always see (AudioTech/BimmerTech etc.)

[joehoe]

Thanks for the input HanC

Updates for anyone who may have been in the same boat I am:

Was looking at used MatchUp7 and Bimmertech amps, found a Bimmertech one for a good price. Installed into my Hifi (Base) with stock speakers and subs. After messing with different tunes, everything is working really well. There is a noticeable increase in volume (40% - 50% depending on music source), and the stock speakers sound decently clear. The bass response is much improved. I think the flapping from the subs before were from the stock amp beginning to clip/being underpowered. I will probably add a trunk subwoofer down the line, and forgo replacing the underseat woofers.

Of course music quality/sound is subjective. My previous car I had Infinity Kappas speakers with a JL W3 12 inch in the trunk. The F30 does not get near as clear as that, but the Bimmertech amp upgrade did make a large enough improvement that I am happy I did the amp change first.

[delecz]

Originally Posted by HansC.

I just did a major overhaul of the base stereo in my 340i (2019 F31) I went with Focal fronts, rears and woofers; all driven by the relatively new Alpine PDP-E800DSP (8×100W) configured to drive the woofers in parallel mode so, in effect, 4×100W for the doors+2×200W for the woofers. I don't see/hear a need for more low end and punch is amazing.

I coded my HU EVO to hifi line out and ran the line outs directly to the amp in effect bypassing the ASD. I then coded the ASD to HIFI and ran the ASD output as input 5 on the amp thereby allowing me to configure ASD levels from Alpine’s DSP tool – pretty neat

The Alpine amp fits perfectly in the rear left well.

After some hours of DSP tuning I became very very happy with the result.

I know that the above is above your budget but I bring it up as an alternative to the proposals you will more or less always see (AudioTech/BimmerTech etc.)

@HansC

I have the same Alpine amp as you do (PDP-E800DSP). I find that the amp tends to lower its volume (overheat protection activated). This is being reported by several people on YouTube as well.
Do you have any issues? I am also running my two SWS (2 ohm) subs in parallel. I'm thinking of replacing them to 4ohm pairs and trying if that helps.
Cheers

[Billfitz]

Two 2 ohm drivers in parallel is a one ohm load. Don't do that. Your amp has eight assignable channels with 2 ohm capability, two of them should be assigned to the woofers.

[delecz]

Sorry my bad. I meant to say that the amp is on parallel mode (2 channels in parallel mode), driving a single 2 ohm woofer/load.
So I have 2 woofers configured this way using 4 channels from the amp.

Impedance per channel on amp is configured as 4 ohms

[Billfitz]

You shouldn't be having a problem. If you go to higher impedance woofers you'll reduce output. I suspect you're just trying to get more out of the unseat woofers than they can give. Big bottom only comes from big drivers in big boxes.

[johnung]

Originally Posted by joehoe

One post on the forums showing the install had the member shaving down a small part of the inside of the enclosure. I also saw a member selling some Earthquakes in the classifieds that came with spacers, so I am assuming those were so that you didn't have to shave anything down? Not 100% sure on this info though, hope someone else can chime in.

I've run across two different spacers for use under the front seats in a BMW with the Earthquake 8" subwoofers- either the SWS-8X (4-ohm) or SWS-8Xi (2-ohm).

1) made by Earthquake, this spacer has two RCA receptacle jacks on the side with two pigtail wires to connect to the subwoofer. This would work well if you are using RCA speaker output jacks from your amp or Line Output Conditioner. Cost is $20/pair. Earthquake part number R8SWS

2) made by Technicpnp. These appear in photos to be a little more substantial. Instead of RCA jacks, this spacer has a stock receptacle that matches the plug on the stock BMW Subwoofer wires. This would be easiest to use if the intention is to replace the stock underseat subs with Earthquake subs. I am not clear on whether the stock BMW subs are 2-ohm or 4-ohm so choose your Earthquake model carefully. $65/pair Part# SWS-8

[Billfitz]

Those aren't RCA, they're binding posts, like these:
https://www.parts-express.com/parts-...pair--091-1152

RCA plugs and jacks should never be used for speaker connections, as that would make it much too easy to connect the output of an amp to the input of a receiver, CD player or whatever, with the result being magic smoke.

You'd use the Technicpnp if you're using the stock wiring to the woofers, the Earthquake if you're putting in the heavier gauge wire that they should be used with.

[delecz]

Originally Posted by Billfitz

You shouldn't be having a problem. If you go to higher impedance woofers you'll reduce output. I suspect you're just trying to get more out of the unseat woofers than they can give. Big bottom only comes from big drivers in big boxes.

Actually there was a hardware issue with my amp and just got it replaced. The new one works fine. The older one had issues where it would automatically turn the master volume down by iteself due to an overheat warning (Strange because it was always running between 30-40 C).

Anyway the replacement amp I received don't have this issue.

[HansC.]

Originally Posted by delecz

Actually there was a hardware issue with my amp and just got it replaced. The new one works fine. The older one had issues where it would automatically turn the master volume down by iteself due to an overheat warning (Strange because it was always running between 30-40 C).

Anyway the replacement amp I received don't have this issue.

Sorry for seeing your post late - Yes, I had the same issue. My amp was replaced twice; first due to the amp completely forgetting DSP settings and the second time because of the master volume going down over time - strange behavior. I btw just just swapped the car for a 2019 X3M40i so a new owner will be enjoying the upgrade.

/HC