E90Post
 


The Tire Rack
 
BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Technical Forums > AUDIO/VIDEO + BLUETOOTH + Electronics/Alarm/Software > Is 250W RMS too much for Logic 7 stock underseat woofers?



Reply
 
Thread Tools Search this Thread
      07-25-2014, 04:35 AM   #1
1DirtyFive
Enlisted Member
9
Rep
39
Posts

Drives: 2010 BMW 135i
Join Date: Nov 2011
Location: Las Vegas, NV

iTrader: (1)

Is 250W RMS too much for Logic 7 stock underseat woofers?

I just brought a 2CH amplifier too power my L7 stock underseat woofers, but didn't know its 250watt rms per channel at 4 ohm(yea what a stupid me). Do you think it will be OK if I keep the amplifiers gain at minimum? any input will help, thanks.
Appreciate 0
      07-25-2014, 06:51 AM   #2
cdgatti
Colonel
cdgatti's Avatar
255
Rep
2,547
Posts

Drives: e90 328i
Join Date: May 2011
Location: KY

iTrader: (4)

Depends... it could work out ok if you can minimize the signal going to it as you need to keep the power to the underseats somewhat balanced with the power going to the other speakers. You may have to reduce the gain on the underseats amp and up the gains on the the other amps.
Appreciate 0
      07-25-2014, 07:31 AM   #3
1DirtyFive
Enlisted Member
9
Rep
39
Posts

Drives: 2010 BMW 135i
Join Date: Nov 2011
Location: Las Vegas, NV

iTrader: (1)

I'm using techincs harness to add that amp to the underseats, and leaving the rest power by the stock L7 amp, so I don't know if I can reduce the signal that goes to the underseats, plus by turning the amp's gain all the way to the left is that what you mean to reduce the gain? thanks a lot.
Appreciate 0
      07-25-2014, 07:42 AM   #4
kaigoss69
Brigadier General
kaigoss69's Avatar
United_States
300
Rep
3,969
Posts

Drives: '08 335i
Join Date: Jul 2008
Location: JAX

iTrader: (6)

You can safely feed the OEM woofers with a lot of additional power as long as you do it responsibly. This means two things:

1. Use the amp's subsonic (or high-pass) filter to cut out the very low frequencies that are most likely to kill the woofers. I recommend setting it at 50hz.

2. Set the gain such that the notes blend with the rest of the system. When you listen, always increase the volume slowly and be aware that the speakers will likely sound distorted or even start popping when they are overdriven.

Also, consider the replacement cost of the L7 woofers. If it were me, I'd put in aftermarket woofers and save the L7s for putting them back in when it's time to sell the car.
__________________
Mobridge DA2 > JBL MS-8 > ARC XDi 600/4 > JBL Gti 408 Mids & Vifa OT19 Tweeters; PG Ti2 1600.5 > Morel HCW-10 & IDMax 15
Appreciate 0
      07-25-2014, 08:43 AM   #5
1DirtyFive
Enlisted Member
9
Rep
39
Posts

Drives: 2010 BMW 135i
Join Date: Nov 2011
Location: Las Vegas, NV

iTrader: (1)

Quote:
Originally Posted by kaigoss69 View Post
You can safely feed the OEM woofers with a lot of additional power as long as you do it responsibly. This means two things:

1. Use the amp's subsonic (or high-pass) filter to cut out the very low frequencies that are most likely to kill the woofers. I recommend setting it at 50hz.

2. Set the gain such that the notes blend with rest of the system. When you listen, always increase the volume slowly and be aware that the speakers will likely sound distorted or even start popping when they are overdriven.

Also, consider the replacement cost of the L7 woofers. If it were me, I'd put in aftermarket woofers and save the L7s for putting them back in when it's time to sell the car.
Thanks a lot for your input Kaigoss, now I'm not that afraid to feed the stockies with that amp. The amp that I got its the Autotek atx1000.2 factory rated 250watt rms X 2 at 4ohm, but people on the internet are saying that amp is way over rated, so I think I'm fine now
Appreciate 0
      07-25-2014, 09:34 AM   #6
kaigoss69
Brigadier General
kaigoss69's Avatar
United_States
300
Rep
3,969
Posts

Drives: '08 335i
Join Date: Jul 2008
Location: JAX

iTrader: (6)

Quote:
Originally Posted by 1DirtyFive
Quote:
Originally Posted by kaigoss69 View Post
You can safely feed the OEM woofers with a lot of additional power as long as you do it responsibly. This means two things:

1. Use the amp's subsonic (or high-pass) filter to cut out the very low frequencies that are most likely to kill the woofers. I recommend setting it at 50hz.

2. Set the gain such that the notes blend with rest of the system. When you listen, always increase the volume slowly and be aware that the speakers will likely sound distorted or even start popping when they are overdriven.

Also, consider the replacement cost of the L7 woofers. If it were me, I'd put in aftermarket woofers and save the L7s for putting them back in when it's time to sell the car.
Thanks a lot for your input Kaigoss, now I'm not that afraid to feed the stockies with that amp. The amp that I got its the Autotek atx1000.2 factory rated 250watt rms X 2 at 4ohm, but people on the internet are saying that amp is way over rated, so I think I'm fine now
Haha, that amp will make a 1000w only during a direct lightning strike!
__________________
Mobridge DA2 > JBL MS-8 > ARC XDi 600/4 > JBL Gti 408 Mids & Vifa OT19 Tweeters; PG Ti2 1600.5 > Morel HCW-10 & IDMax 15
Appreciate 0
      07-25-2014, 10:37 AM   #7
bmw325i
Major General
223
Rep
5,120
Posts

Drives: 2006 BMW 325i
Join Date: Oct 2010
Location: United States

iTrader: (8)

It's always good to have more power than you need you just need to know what you're doing. That amp will probably start clipping before you blow the underseats. Most entry level audio companies just make up numbers for what their amps are rated at. If you don't have a trunk sub I would set the subsonic or high pass filter at 35hz or 50-60hz if you do have a sub.
Appreciate 0
      08-03-2014, 02:24 AM   #8
1DirtyFive
Enlisted Member
9
Rep
39
Posts

Drives: 2010 BMW 135i
Join Date: Nov 2011
Location: Las Vegas, NV

iTrader: (1)

I just got my amplifier installed two days ago, after I tweak the settings a little on the amplifier, all I can say is WOW!! I highly recommended if you wonna improve the stock L7/HarmanKardon system, the bass hits a lot more harder,tighter,cleaner, the tone of the bass is more refined and for some reason it made the front stage sound cleaner.

Well the ATX1000.2 actually sounded better than I though. I have the gain set at 2/6 of a turn and its pretty loud already, no bass boost, I end up have to set the high pass filter somewhere between 70-80HZ, if i set it below that my woofers will make popping sound on some heavy hitting bass near max volume, well I guess you just have to get a subwoofer to play them low frequency's, and thats what I will do next.

I have to say thanks to all good fellas on the forum for the help, specially thanks to kiagoss for his advise on adding center tweeters and amping the underseats it made the L7/HarmanKardon system sounded so much better, lastly thanks to TECHNIC for his amazing harness
Appreciate 1
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 03:49 AM.




e90post
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST