So exactly what does the speaker amp do?
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- Joined: Mon 02 Aug, 2010 20:55
- Posts: 518
- Location: Basingstoke
So exactly what does the speaker amp do?
Silly question I know, but I've recently bypassed (ie removed) the original BMW speaker amp from the footwell spaeker, and installed new speakers and head unit. Out of curiosity I reconnected the original BMW Business Unit head unit (still without the speaker amp though) and to my surprise it all sounds fine. To my ears it's actually better than the new head unit so I'm keeping it for the moment.
My question is though what does the BMW speaker amp do, as it all sounds fine without it? Also can I damage anything by not using the amp?
My question is though what does the BMW speaker amp do, as it all sounds fine without it? Also can I damage anything by not using the amp?
2001 Titan Silver 2.2 Sport
Removing front speakers
What method did you use to access the Front speakers? Which pieces of the interior have to be removed to gain access to the speakers in the foot wells?
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- Joined: Mon 02 Aug, 2010 20:55
- Posts: 518
- Location: Basingstoke
I followed the BSW directions, page 5 onwards:
http://www.bavariansoundwerks.com/produ ... adster.pdf
Although it's for a left hand drive car the steps are the same, you've just got think in mirror image!
Also found it easier to pull up the sill covers before taking off the kick-panel, but it does take quite a bit of force to do so.
http://www.bavariansoundwerks.com/produ ... adster.pdf
Although it's for a left hand drive car the steps are the same, you've just got think in mirror image!
Also found it easier to pull up the sill covers before taking off the kick-panel, but it does take quite a bit of force to do so.
2001 Titan Silver 2.2 Sport
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- Joined: Mon 02 Aug, 2010 20:55
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- Location: Basingstoke
- chris1984_99_99
- Joined: Sat 01 May, 2010 17:24
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- Location: Troon
When I first got my car the amp in the passenger footwell wasnt working. Infact I didnt know there was one! I changed the head unit and got 2 new speakers behind the seats and the sound was still terrible! clipping and popping as soon as i turned it up to a volume level where i could actually hear it.
Took the car to a car to halfords to get speakers for the footwells and the guy there told me theres an amp and it isnt wired in right. So off i went to a mate and got it up and running.
....I havnt touched the setup since. It sounds fantastic. Plenty of bottom end bass, even with the roof down.
Took the car to a car to halfords to get speakers for the footwells and the guy there told me theres an amp and it isnt wired in right. So off i went to a mate and got it up and running.
....I havnt touched the setup since. It sounds fantastic. Plenty of bottom end bass, even with the roof down.
the footwell amp is what is known as a 'power amp' and it in simple terms, is the muscle.
The volume control on the headunit adjusts a low level (normally line level) signal which it sends to the poweramp, which then increases it by a fixed rate upto 'speaker level' so that is the correct level to drive the speakers.
HTH
The volume control on the headunit adjusts a low level (normally line level) signal which it sends to the poweramp, which then increases it by a fixed rate upto 'speaker level' so that is the correct level to drive the speakers.
HTH
The BMW head unit is a standard low power head unit with speaker outputs that drive the rear speakers and door tweeters directly. I imagine BMW thought the foot-well speakers would need more power, so they added the speaker amp as a booster. The speaker amp takes the front speaker outputs from the head-unit, boosts them and sends to the mid-bass foot-well speakers.
Since this speaker amp takes speaker input as opposed to line level (RCAs) is it important to bypass it when adding an aftermarket head-unit since most aftermarket head units are high power (25W to 50W per channel).
Since this speaker amp takes speaker input as opposed to line level (RCAs) is it important to bypass it when adding an aftermarket head-unit since most aftermarket head units are high power (25W to 50W per channel).
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- Joined: Mon 02 Aug, 2010 20:55
- Posts: 518
- Location: Basingstoke
In my zed I've got a Kenwood KDC-w7044u head unit with just about every sound customization going, with Fusion components at the front and Kenwoods in the rear. Initially I bypassed the footwell amp and played around with the sound settings, but just couldn't get it right, the sound didn't seem to have any 'oomph'.
I then reconnected the footwell amp and now have the oomph that I'm after, only problem is if I turn it up too loud I get a bit of distortion.
I notice I have some RCA connectors (lower level?) for connecting to Front outputs a seperate amp, would I better off using these to connect to the footwell amp, but keep the existing speaker connections for the rears?
As you can tell I'm a bit of a at ICE!
I then reconnected the footwell amp and now have the oomph that I'm after, only problem is if I turn it up too loud I get a bit of distortion.
I notice I have some RCA connectors (lower level?) for connecting to Front outputs a seperate amp, would I better off using these to connect to the footwell amp, but keep the existing speaker connections for the rears?
As you can tell I'm a bit of a at ICE!
2001 Titan Silver 2.2 Sport
I am surprised the footwell gave you more ooomph. What is the output power of your head unit?wonderloaf wrote:In my zed I've got a Kenwood KDC-w7044u head unit with just about every sound customization going, with Fusion components at the front and Kenwoods in the rear. Initially I bypassed the footwell amp and played around with the sound settings, but just couldn't get it right, the sound didn't seem to have any 'oomph'.
I then reconnected the footwell amp and now have the oomph that I'm after, only problem is if I turn it up too loud I get a bit of distortion.
I notice I have some RCA connectors (lower level?) for connecting to Front outputs a separate amp, would I better off using these to connect to the foot-well amp, but keep the existing speaker connections for the rears?
As you can tell I'm a bit of a at ICE!
I suspect the distortion you heard was over driving the foot-well amp. Its not that great really.
If you want more then a separate amp is needed. don;t try to drive the foot-well amp with RCAs it's not worth it.
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- Joined: Mon 02 Aug, 2010 20:55
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- Location: Basingstoke
That 50w per channel will overdrive it. The BMW unit is much less.wonderloaf wrote:Power of my HU is 50W per channel max, 30W DIN 4534 (RMS?).
Just been out and removed and bypassed the amp again to give it another go, maybe I had the HU set up wrongly previously as it was new and I was unfamiliar with it.
What you might be experiencing with poorer sound comes from the door tweeters now being driven way too hard compared to the mid-bass in the foot-well. In the standard setup the foot-well mid-bass units get boosted by that little amp, but the tweeters do not. The tweeters run directly from the head unit and no doubt BMW took this into account when balancing the system. When you bypass the foot-well amp and use a high power head unit you are now 'boosting' both mid-bass and tweeters. As a result the tweeters are getting much more power and this is affecting the balance. You may also be over-driving the original door tweeters, but less likely.
What you do next depends on your appetite for removing the door cards and replacing the tweeters.
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- Joined: Mon 02 Aug, 2010 20:55
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- Location: Basingstoke
Sorry should have explained myself better, have also replaced the tweeters in the doors with those that came with the component speaker set. Only thing is that I didn't use the crossovers that came with the set as I couldn't see an (easy) way of wiring through the door hinge. Will this make a big difference?
I've got Fusion components and I read somewhere that the tweeters have built in crossovers, don't know if that's true or even possible.
BTW thanks for answering these posts, these are things that have been on my mind but never got around to asking!
I've got Fusion components and I read somewhere that the tweeters have built in crossovers, don't know if that's true or even possible.
BTW thanks for answering these posts, these are things that have been on my mind but never got around to asking!
2001 Titan Silver 2.2 Sport
When you replaced the tweeters, did you remove the capacitor as well or leave it in place? It was in the door, quite close to the tweeter.wonderloaf wrote:Sorry should have explained myself better, have also replaced the tweeters in the doors with those that came with the component speaker set. Only thing is that I didn't use the crossovers that came with the set as I couldn't see an (easy) way of wiring through the door hinge. Will this make a big difference?
I've got Fusion components and I read somewhere that the tweeters have built in crossovers, don't know if that's true or even possible.
BTW thanks for answering these posts, these are things that have been on my mind but never got around to asking!
It would be a good idea to install the crossovers as the new speakers were designed to use them. A way you can install these is to connect the crossovers into the wires that come from the head unit where you bypassed the foot-well amp. You can hide them above the panel under the glove box. These wires from the head unit also go to the door tweeters, so connect them to the tweeter output. Then run new wires from the crossovers to the head-unit and connect to the front speaker output. You can patch into the head unit at the ISO to BMW adapter. Also run new wires to the mid-bass in the foot-wells.
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- Joined: Mon 02 Aug, 2010 20:55
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- Location: Basingstoke
Just did a like-for-like swap with old tweeters so guess the capacitors are still there.
When I installed the hew HU and speakers it was mid-winter and I have to work on drive so wanted to get things done ASAP, but now the weathers warmer and drier will take a look at rewiring things properly.
Thanks for all your advice, much appreciated
When I installed the hew HU and speakers it was mid-winter and I have to work on drive so wanted to get things done ASAP, but now the weathers warmer and drier will take a look at rewiring things properly.
Thanks for all your advice, much appreciated
2001 Titan Silver 2.2 Sport
The capacitor is just before the actual tweeter, after the yellow plug. If you disconnected the plug and took out the whole lot, then the capacitor won't be there any more. I recently did a full replacement of the front speakers, take a look at my thread for pics etc: http://www.zroadster.net/forum/viewtopic.php?t=30471
1997 2.8 Z3 | Gallery Thread
This thread is full of technical nonsense. 'Oer driving' a speaker WILL NOT cause poor sound quality. Poor sound quality is caused by an amplifier 'clipping' the signal as it is under powered for the amplification levels being requested of it.
Also, ignore wattage figures, they are useless for the most part.
Also, ignore wattage figures, they are useless for the most part.