Head units, pre-outs and amplifiers???

[DAD190E1990]

Hi
I drive a '90 190E.
I am upgrading from the original 1990 blaupunkt radio cassette and i have some questions based on my small amount of knowledge.

1 - If the head unit feeds through the 'Pre-Out' into an amplifier and then runs 4 speakers and a subwoofer, do the normal speaker connections from the head unit become redundant?

2 - Does the 'pre' in 'Pre-Out' mean it by-passes the amplifier in the unit or does bass and treble stuff still work as normal?

3 - I am also buying a seperate DIN sized DVD player and running that into two rear headrest screens. Do amplifiers generally allow for 2 input sources or would that be a specialist item. If possible, i would like to run the DVD head unit through the same amplifier and speakers as the CD head unit. If most Amplifiers don't allow for 2 input sources, is there a way of wiring a switch because both would never be used together - could a switch be put in-line between each head unit and the amplifier?

I only want to do this once. The total parts i'm putting together are a CD head unit,10 disc Boot changer and replacing every speaker wire, speaker, installing crossovers and tweeters in the headrests. DVD monitors in headrests, subwoofer install and with all of this comes a full interior strip and rebuild. Also the double DIN centre dash has to be put in and the whole system requires 2 remote sensor 'Eyes' for the steering wheel and hand held remote controls. I am pretty much up on this but the questions above would help me move in the right direction, and any other comments based on my plan above would be very much welcomed.
Thanks for any help i recieve with this.

 

[Bolide]

Stereo queries

1 - If the head unit feeds through the 'Pre-Out' into an amplifier and then runs 4 speakers and a subwoofer, do the normal speaker connections from the head unit become redundant?

Yes

2 - Does the 'pre' in 'Pre-Out' mean it by-passes the amplifier in the unit or does bass and treble stuff still work as normal?

EQ & etc work as normal

3 - I am also buying a seperate DIN sized DVD player and running that into two rear headrest screens. Do amplifiers generally allow for 2 input sources or would that be a specialist item. If possible, i would like to run the DVD head unit through the same amplifier and speakers as the CD head unit. If most Amplifiers don't allow for 2 input sources, is there a way of wiring a switch because both would never be used together - could a switch be put in-line between each head unit and the amplifier?

Your new HU (Head Unit) may allow for additional inputs and it's very much recommended that you get a unit that does. There's no real need to get a separate DVD player unless you want a satnav HU or want to run two sources at the same time

I only want to do this once. The total parts i'm putting together are a CD head unit,10 disc Boot changer and replacing every speaker wire, speaker, installing crossovers and tweeters in the headrests. DVD monitors in headrests, subwoofer install and with all of this comes a full interior strip and rebuild. Also the double DIN centre dash has to be put in and the whole system requires 2 remote sensor 'Eyes' for the steering wheel and hand held remote controls. I am pretty much up on this but the questions above would help me move in the right direction, and any other comments based on my plan above would be very much welcomed..

I'd lay out the audio gear on the bench, make all the audio interconnections & familiarise yourself with the way it's going to work & connect. It'd be a good idea to hook up a car battery & a pair of old speakers to test it then too

I'd run a new main feed direct off the battery via a circuit breaker and use that to feed the system. Use cable of sufficient gauge for the current draw of the kit you're using and remember the earth cable for the bass amp has to be as heavy as the power feed cable

I'd leave the existing car audio loom in, tape it out of the way and wire everything fresh. That way the existing loom can be used if you sell the car

IMHO good power, good earths, one pair of excellent front speakers and big enough amps are the keys to good car audio

You'll find lots of help on the Talk Audio Forum
http://www.talkaudio.co.uk/vbb/forumdisplay.php?f=23

- but do some research on the Forum before asking questions and you'll get more help


Nick Froome
www.w124.co.uk

 

[DAD190E1990]

Hi
My thanks for your opinions on this. I have chosen a Blaupunkt Modena MP54 for the Headunit and two generic portable DVD players with integral screens - I am modifying the backs of the front seats to provide a location for the two seperate players. The Amplifier is a surround item with 4 speaker channels, one centre and a sub channel. The cd changer, New fuse board, and amp sit together, installed into the boot and out of sight. I have bought new speaker wire from the boot amp and have now to strip the interior to allow me to fit this. The seat mods are the biggest as they involve the tweeters for the front component speakers set into the headrests, behind a tristar badge/grill with a wood surround. It's as fiddly as it sounds but looks the business on paper and if the fronts are succesful, so will the rear tweeters be set into the rear headrests. The centre speaker is a small self contained unit so that's being set into the centre arm rest and the sub is positioned right behind the rear armrest - i believe there is a panel that can be removed to create a straight through hole to the armrest aperture, but i have not checked my car interior yet and can't be sure about this. Even with out a hole in front of the sub, i'm sure it will work well. That's about it, except for it's already been fun trying to work out where all this stuff is going and how to hide it all without looking tacky or obvious. Once all this stuff is completed, i am still using the Taxi dash with two DIN aperture's as i'm installing a slide-out cradle and power supply for my sat nav. in the second DIN hole - with a visit to an electronics shop, i might look at motorising it. I have priced the whole job at about 600 GBP and roughly 3 weekends work, when i can fit the days into the months, so we have set a date for easter to be done. I will photograph the work and post it here as a kind of how-to and what not to do, especially with the boot-install.
Thanks again for the help, it has helped me get some good plans together and buy the right kit.

 

[Bolide]

Speakers in headrests

The only problem with speakers in headrests is that as you move your head you move on- and off-axis of the speaker. This means that the amount of top end varies as does the loudness. I had a Recaro headrest with speakers and found it annoying in the end. I'd advise against it, however a good idea it sounds in theory


Nick Froome
www.w124.co.uk

 

[DAD190E1990]

Thanks for the advice Nick and yes, you are right and i had not thought about the rotary speaker effect - plan has been modified. The tweeters are now going to become part of the plastic door pocket, again with the tristar and wood trim i have designed.
I am very grateful for your experience and advice on this and i have noticed that my plans now are a lot more simple and straight-forward than the original install plan.
The car comes off the road this week for a month whilst the new steering is taken care of, so i'll get the interior out and the hard part done then. With any luck and time permitting, i could be 'Rocking Out' by the end of March.

As a point of interest, the component speakers and the sub are for one very good reason - the type of music i play in the car. It's not the 'Beepy-Beepy' thudding nonsense but rather four lads from London with real instruments. The SubWoofer is for the sole purpose of the late Mr Keith Moon and Mr John Entwhistle to adjust my spine with the kick of the drums, the Tweeters are for The Lord of the Strings, Pete Townshend to gently tear what's left of my eardrum and the amp is for Mr Daltrey to let the rest of the world know what decent ****** music is. As well as this there may be a flashing past of Queen, Steely Dan and Pink Floyd's 'The Wall'.

When this is finished, me and half a tank of petrol are going out for a pointless drive out to get lost in the hills around Co. Durham, i just can't wait.