Anyone replace the subs under our seats with the Rockford Fosgate T3-BMW-SUB 8?

[Travis1807]

Power BMW® 8” Direct Fit Subwoofer
T3-BMW-SUB
The Power T3-BMW-SUB is an 8” slim subwoofer designed as a direct fit replacement/upgrade for select BMW® models. Speaker features a BMW® factory connector and 150 watt power handling capacity.

Size 8"
Power Handling (Watts RMS)150 Watts RMS
300 Watts Max
Speaker ConnectorCustom BMW® Terminal
Shipping Weight3.85 Lbs. (1.7 Kg.)
Fs (Hz)38
Qes0.63
Cutout Diameter7.7 in. (195 mm)
Nominal Impedance4-Ohm
Voice Coil Diameter2.0" (50.80 mm)
Mounting Depth1.2 in. (31.2 mm)
Qts0.49
Qms2.26
SPL (dB @ 1w/1m)88
CEA-2031 CompliantCEA-2031 Guidelines
Vas (Liters)40.6
Xmax (mm)7
Re (Ohms)3.7
Le (mH)0.61

//www.rockfordfosgate.com/products/details/t3-bmw-sub/

This sub is a direct replacement for the 8 ohm sub that comes with the B&O sound system (not sure about the HK system) This sub is rated at 3.7 ohms so you should get a good deal more bass out of them.

If anyone has made the switch to these I would really appreciate a review on them.

[J///MJ]

Is it really worth messing with the B&O system? Because that's what I have :

[Nuckle]

Originally Posted by J///MJ

Is it really worth messing with the B&O system? Because that's what I have :

Not in my opinion but others feel that it is. I think the B&O system is pretty nice for being an integrated factory system.

[botis1028]

I agree that the B&O has potential - it’s much better than my F10 M5 B&O. I just cannot figure out the proper Equilizer settings.

What is everyone running for optimum sound??

[iconoclast]

If this is plug and play as it states and will improve the punch that the B&O system is lacking I would considering installing them. Has RF quality improved over the years? I don't recall them ever being a high end audio equipment company but what many HS/College kids put in their trunk.

[Jenner]

Looks identical to the OEM part...just 4ohm rather than 8ohm. That's how they are getting their power increase.

I would skip on this and use the Earthquake BMW replacement subwoofers like I did. The price is great and so is the improvement in sound.

Everything you need to know is in post #26. This link should take you directly there:
http://f15.bimmerpost.com/forums/sho...5&postcount=26

[Travis1807]

Originally Posted by Jenner

Looks identical to the OEM part...just 4ohm rather than 8ohm. That's how they are getting their power increase.

I would skip on this and use the subs I did. Everything you need to know is in post #26. This link should take you directly there:
http://f15.bimmerpost.com/forums/sho...5&postcount=26

i went yo your post and checked out the link through amazon. It looks like Earthquake carries a 2ohm version. thoughts compared to the 4ohm??

[Jenner]

Originally Posted by Travis1807

i went yo your post and checked out the link through amazon. It looks like Earthquake carries a 2ohm version. thoughts compared to the 4ohm??

Based on my personal experience you don't want the 2 ohm for 2 reasons.

1) The B&O amp is expecting a 8 ohm load. When you lower the resistance you increase the power, which in turn produces more heat/strain on the amp. The extra bump in power from 8 to 4 is plenty and should be well within the headroom of the B&O amp. As I said in my link above I did this on other B&O systems with no issue. 2 ohm might work but could overheat the amp and wear it out prematurely or trigger thermal shut downs if you play it loud for too long.

2) The 4 ohm earthquake replacement subs hit so much harder and play so much louder I had to turn down the bass enhancement setting and EQ significantly compared to the factory subs. I think the 2 ohm would play too loud, relative to the other speakers that you would end up with a very bass heavy boomy system at low and normal volumes that could potentially sound worse than the factory subs overall.

So the short version is you don't need or want the 2ohm. There are no pros to them only cons IMHO.

[Travis1807]

Originally Posted by Jenner

Based on my personal experience you don't want the 2 ohm for 2 reasons.

1) The B&O amp is expecting a 8 ohm load. When you lower the resistance you increase the power, which in turn produces more heat/strain on the amp. The extra bump in power from 8 to 4 is plenty and should be well within the headroom of the B&O amp. As I said in my link above I did this on other B&O systems with no issue. 2 ohm might work but could overheat the amp and wear it out prematurely or trigger thermal shut downs if you play it loud for too long.

2) The 4 ohm earthquake replacement subs hit so much harder and play so much louder I had to turn down the bass enhancement setting and EQ significantly compared to the factory subs. I think the 2 ohm would play too loud, relative to the other speakers that you would end up with a very bass heavy boomy system at low and normal volumes that could potentially sound worse than the factory subs overall.

So the short version is you don't need or want the 2ohm. There are no pros to them only cons IMHO.

Appreciate the info. thank you

[bluelodge400]

After reading your subwoofer upgrade post, I am doing the exact same thing.
I went to install everything on Sunday but I did not have the T50 Torx socket to unbolt the seats. So hopefully I can get to it this weekend.

I think the hardest part with the B&O system is trying to find the right EQ settings.

Originally Posted by Jenner

Looks identical to the OEM part...just 4ohm rather than 8ohm. That's how they are getting their power increase.

I would skip on this and use the Earthquake BMW replacement subwoofers like I did. The price is great and so is the improvement in sound.

Everything you need to know is in post #26. This link should take you directly there:
http://f15.bimmerpost.com/forums/sho...5&postcount=26

[Jenner]

Originally Posted by bluelodge400

After reading your subwoofer upgrade post, I am doing the exact same thing.

Awesome I hope you are as pleased with it as I am. Let us know!

[m32]

sub'd

[botis1028]

Can anyone help me with the equalizer settings? I love listening to music in car but could not figure it out

[Jenner]

There is no one size fits all. Depends on the music and your own ear/preference.

[Ryan5034]

I bought 2 ohm earthquakes at first and they are too loud. Buy the 4 ohm ones. You will probably still have to turn the bass /eq down some.

[Djvolume]

Can anyone share their experience compared earthquake to bavsound subs? I currently have the bavsound once installed

[Travis1807]

so i just replaced my B&O subs with the 4 ohm earthquake subs. it took about an hour and a half and was totally worth the time and money. the installation was straight forward and I'm happy with the results. these subs aren't anything like having a sub in a box with a good amp but they are a 100% improvement over the B&O's.

[bluelodge400]

Hi Travis, I finally got around to replacing the B&O subs as well. Overall, it is a very nice improvement. It’s a good amount of “thump” over the stock subs. I am still trying to dial-in the EQ settings.

Here are some takeaways for anyone thinking of doing this quick mod:
For $230 and a little over an hour of your time, this upgrade was well worth it. It’s a much easier mod than trying to replace the orange side markers(I gave up trying to install those damn things!). I was surprised to see that the B&O’s were a little heavier than the Earthquake’s but the Earthquakes do pack more of a punch and have a noticeable improvement in sound quality. The only downside to this install was not having the ability to reinstall the grill covers. The seats were very easy to remove and realign. Use a Torque Wrench set at 45-50lbs when reinstalling the seat bolts. You don’t want to over or under tighten the bolts.
The pink OEM wire clip does not need to be cut. The wires can be removed from the clip and paired to the sub wires. I used electrical tape to attach them.

[Ehloo]

Do you have pics of the exposed subs. Have two young kids and they are messy monsters. Not having some protection with the covers would force me to the RF or Bav

Originally Posted by bluelodge400

Hi Travis, I finally got around to replacing the B&O subs as well. Overall, it is a very nice improvement. It’s a good amount of “thump” over the stock subs. I am still trying to dial-in the EQ settings.

Here are some takeaways for anyone thinking of doing this quick mod:
For $230 and a little over an hour of your time, this upgrade was well worth it. It’s a much easier mod than trying to replace the orange side markers(I gave up trying to install those damn things!). I was surprised to see that the B&O’s were a little heavier than the Earthquake’s but the Earthquakes do pack more of a punch and have a noticeable improvement in sound quality. The only downside to this install was not having the ability to reinstall the grill covers. The seats were very easy to remove and realign. Use a Torque Wrench set at 45-50lbs when reinstalling the seat bolts. You don’t want to over or under tighten the bolts.
The pink OEM wire clip does not need to be cut. The wires can be removed from the clip and paired to the sub wires. I used electrical tape to attach them.

[alvav]

Audison, Focal and Rainbow also have direct replacement subs. I'm thinking that they are more in line with the B&O quality. Twice the price of the Earthquakes, though. Anyone try one of these?

[Ryan5034]

I used these spacers with the earthquake subs and the covers fit just fine.

https://www.amazon.com/Earthquake-So...ake+spacer+bmw

[Twin Peaks]

*Subscribed*

For any of you who have measured or can direct me to the information for B&O. What is the mounting depth of the subs under the seats? Using the Earthquake subs, have you maxed out volume? If so how did the subs handle it, was there a smell or tapping sounds or any issues? I have a very eclectic taste in music and listen to everything so more bump under the seats sounds like a great upgrade to me!

My factory B&O sounds great but like others mentioned, the bass turned up starts to sound punchy at low/mid volumes.