[Dwtk]

Hi Guys

I wanted to run some questions by the brain trust. I have a Zenec 3215 head unit in My 08 E93. ( if your interested in it you can look up my review here.

http://www.amazon.co.uk/Zenec-Upgrad...rds=zenec+3215 )





I recently updated to the Alpine upgrade kit because I didn’t want to do too much pulling apart the car . ( But I did anyway putting in the kit. 2.5 hours my ass . took me like 2 days ) . Anyway back to the point . After connecting it all . I felt the midrange speakers putting out more bass than the stock subs. I also felt I didn’t have any control over the subs as putting up the bass on the head unit puts the base on all speakers. So I have decided to upgrade the under floor subs to Earthquakes SWS 8 but as you guys know the alpine class D amp doesn’t produce enough power so I have decided to get another amp ( cheap one of ebay MBQ345 See spec below ) . With the subs powered off this amp . The headunit has RCA Sub out ( See pic below ) . So I will be able to control subfoofer level from the headunit and X cross overs freq for midrange front and rear speakers.

MY QUESTIONS

1) My Question is can is since Im not using the sub outputs from the Alpine any more can I use them on the back 2 speakers in my E93 or is there some cross over / filtering done on the frequency for these channels coming out of AMP. At the moment the rear speaker in my E93 are stock but I may change.

2) Is my new Amp selection and Earthquake pairing the best combination . Amp pushs out 125 RMS per channel at 4 Ohms. The Earthquakes SWS -8 are 150 RMS at 4 ohms. Are these the best subs for this set up ?

3) Any suggestions on improvements on set up .






MBQ354 2000W 2/4-Channel Bridgeable MOSFET Power Car Amplifier



http://www.ebay.co.uk/itm/1216563374...%3AMEBIDX%3AIT
Features
• 4 Channel / 2 Channel
• Bridgeable Operation
• Built-in MOSFET POWER
• 2000 W Max Power Output
• Stereo/Mono Setup Simultaneously
• 4 Way protection circuit
• Power-On LED
• Dimensions : 260 mm x 180 mm x 48 mm
• Weight : 2.8 Kg
Technical Specifications
• Supply Voltage : 11 ~ 15 V DC
• Power Output 4 Ohm : 60 W x 4 RMS
• Power Output 2 Ohm : 80 W x 4 RMS
• Bridge Output 4 Ohm : 125 W x 2
• Frequency Response : 20 Hz~36 KHz (-1 dB)
• Signal Noise Ratio : > 90 dB (+A)
• Input Impedance : 22 K Ohm
• Input Sensitivity : 200 mV - 2 V
• T.H.D. : < 0.05 %
• Hi Pass Freq. : 50 – 500 Hz
• Low Pass Freq. : 50 - 500 Hz

THanks Guys Ish

[Dwtk]

Has no one got an opinion

[cdgatti]

Are you using the rca outputs from the zenec or the powered outputs designed to go right to the speakers?

[Dwtk]

Originally Posted by cdgatti

Are you using the rca outputs from the zenec or the powered outputs designed to go right to the speakers?

Im going to use the RCA from the Zenec for Subwoofer out only . These will go to the New MBQ amp which in turn will power the underfloor Earthquakes.

The front door Hifi upgrade speakers use the OEM integration. They connect to the normal speaker wiring from harness then go to Alpine Class D amp where they are amped and outputted . ( Alpine hifi upgrade kit ) .

As people have said on this forum the earthquakes wont get enough power from the Alpine amp . Thats why have got another amp to do just subs and also decouple the subwoofers from the rest of the frequencies as I can control the sub level via the head unit .

My main questions are .

1) can I use the 2 channels on the alpine which were being used for base ( underfloor subs ) to power rear speakers. is there any freq filtering done on the alpine upgrade amp. I understand I will have to tap into the harness connections on the alpine hifi amp. I may need to upgrade the rears as people have said amping crap speakers will just lead to crap sound .

[Dwtk]

anyone got answer on how the alpine hifi upgrade amp works.

can I use the 2 channels on the alpine which were being used for base ( underfloor subs ) to power rear speakers. is there any freq filtering done on the alpine upgrade amp. I understand I will have to tap into the harness connections on the alpine hifi amp. I may need to upgrade the rears as people have said amping crap speakers will just lead to crap sound .

[bmwmsport]

I'm looking at getting an Alpine amp for my car, too. Curious as to if you like it or not.

[Dwtk]

the mid rage is great defo improvement but the base isnt that good . Problem with the amp is the Head unit . Stock or aftermarket uses the standard harness which sends all freq to amp . Alpine amp amps the sound and sends it all speakers. The door speakers have a crossover for tweeters but what you will find the base it coupled . Which means if you put the base up on head unit . the subs and mids both get the same base which means it doesnt sound good.

Pros of system

- Plug and play . ( even though it will take you 2 days and you will brake a clip of two 0
- Slim mids and tweeters are normally expansive and you get these and amp for a desent price.

Cons

Base is not good. Better than before but still not what I would expect. yout gonna have to get a another amp and earthquakes and decouple subs from system.

[bmwmsport]

That's what I was planning on.

My underseats aren't hitting at all. Don't know what the issue is there.

Will probably get a corner 10" JL or Alpine sub with another amp down the road.

For now, just the alpine amp will work great for what I'm trying to do.

[ctuna]

You need around 50 watts or more for door speakers
for door speakers to have much impact.
100 would be better with some of the aftermarket speaker kits.
Most have come to the conclusion that if you are getting
something like the Alpine upgrade you might as well get
an aftermarket amp like the JL 600/6 that has real impact.
And now there are a lot of three way speaker kits from
Jehnert , Gladen and Diamond audio plug and play for BMW that are awesome .

The base system has no bass from the under seats because it has
cheap 6.5 inch speaker and the Head Unit is trying to drive those
and the front doors in parallel.

Even the next level BMW system the Hi Fi has little bass output
with its underpowered amp.


Something bothers me about the specs on that MB amp its a 2000 watt amp that
only puts out 60 watts per channel = 240 watts total to the speakers .
Where as the Jl 600/6 is a 600 watt amp that puts out 75 watts per channel x 6
= 450 at the speakers. Doesn't seem like the MB is very efficient which means
a greater load on the battery and electrical system.

A lot of us on the stereo board regard rear speakers as a waste
of money just running the speakers of the HU.

A Head Unit will buy you a lot of features but not sound quality
in general but with the base system most aftermarket Head Units
will be better.

Some examples of base system upgrades

Base System Upgrades
http://www.e90post.com/forums/showthread.php?t=445266
http://www.monsteraudiodesign.co.uk/
http://www.1addicts.com/forums/showthread.php?t=634957
http://f30.bimmerpost.com/forums/sho....php?t=1003810
http://www.e90post.com/forums/showthread.php?t=822366
http://www.e90post.com/forums/showth...1#post16679904
http://www.e90post.com/forums/showthread.php?t=581379
http://www.e90post.com/forums/showthread.php?t=451941
http://www.e90post.com/forums/showthread.php?t=540954
http://www.e90post.com/forums/showth...ghlight=Dotech
http://www.e90post.com/forums/showthread.php?t=495855
http://www.e90post.com/forums/showthread.php?t=494299
http://www.diymobileaudio.com/forum/...morel-jbl.html
http://www.e90post.com/forums/showth...1#post16679904
http://www.e90post.com/forums/showth...ht=amp+upgrade
http://www.bimmerfest.com/forums/sho...d.php?t=550771

Better to plan the whole thing out than to start adding stuff to fix
things along the way.

If you are adding a trunk sub the sws-8 for the under seats is regarded as a bad choice
since its a sub to. Unless you are bass head. Some of the other under seats that play
further up into the midrange would give more balance to the system.
I thought I read somewhere that the Alpine amp had 85 watts per channel maybe there
are two versions of that kit.

[Dwtk]

It seems a waste not to do anything with the base outputs on the alpine amp ( as you say they are underpowered and useless to get full power of earthquakes) would it be worth bridging them with the front door channels for more power or will that be too much power for the alpine door speakers and tweeters. or swaping the output of the amps so the base channels power fronts ( Eg 40 w per channel )

[Dwtk]

can anyone confirm the RMS per channel on the alpine amp . and what the doors speakers RMS is. theres conflicting information . some say 80 W per channel some say 70 W per channel others say 25W for fronts. bit confused. BMW documentation is rubbish

[Dwtk]

So I fitted some components in the rear . I tried amping them from the alpine upgrade bass output as I have another amp for the underseat subs . But it looks like the hifi amp does some filtering before it outputs to the green connections . ( bass on harness ) . My question is there anyway to remove this filtering so I get the mid and high like the fronts ?