Keep only Avant speakers and surround module (DIY heavy mod)?

Hello,

I'm wondering if anyone has tried to remove the surround module and speakers from an Avant to use it as a centre speaker / "receiver"?

Has been giving it a lot of thinking lately and cannot see why that shouldn't be possible...

BR

Riven

Never tried it myself, but it is possible, will definitely make the best centre speaker if you adapt the connectors to be a powerlink connector you will be able to connect it to a beosystem processer etc.

Let me know how you get on as ive also got a pair of avant speakers sitting on my shelf

 

Hi,

using speaker and amplifier is possible diy projekt but you have to bulid a powersupply for it, using the surround module it´s a lot more difficult

but not impossible if you have the time for it, (construction of new own programmed processor board to comunicate with surround board

 

Thought I'd re-activate this thread as I have recently salvaged the 'wall' from a 32 VCR Avant including speakers and amplifiers. My 'project' is to use this as a 'backdrop' for a wall mounted Beovision 7 with the Avant speakers providing the sound output. Has anyone successfully done this?

I have very limited electronics knowledge so my first thought was to use a Beolink passive to take the output from the powerlink outputs on the BV7 to drive the speakers however this leaves the problem of the speakers requiring some sort of crossover network to drive the tweeter and woofer. The wiring suggests that this currently takes place within the Avants amplifiers so my thoughts turned to using both the amps and speakers from the Avant (it would be great to use the dedicated amps) but this leaves me with the problem of how to power the amps and how to feed the signal?

The specs from the service manual suggest they require a 20v supply. Is there something I could buy 'off the self' that would do the job? And would I need a separate one for each amp? 

As far as the signal is concerned can I feed this through one of the powerlink din to line out cables available?

Any advice appreciated especially if someone has already achieved this!

Thanks

OK I've given up on the idea of using the amps from the Avant and am going down the route of using a Beolink passive to drive the speakers.

This leaves just one issue - sourcing a passive 2 way crossover suitable for the Avant speakers. I have no idea what I'm looking for. Can anyone with some knowledge advise me what I should be looking for? There are many available on eBay but don't want to buy something unsuitable.

Thanks in advance.

I did a search for you.

Hopefully is it helpfull for you. I made a diagram with the required connections/wiring

 

Here the topic (in dutch) with pictures from also the MX7000 boards.

http://archivedforum2.beoworld.org/forums/p/1120/10446.aspx#10446

The RF avants have a different amplifierboard.

Did you have any luck with this project.

I recently ressurrected a the speaker and the amps from a Beovision Avant 32' CRT VCR.  I'm wanting to use them to attachedto a CD player.

THerefore need to attach power and work out how to attache the CD. 

THe CD player only has RCA plugs that I would have to make some inputs into the amps for.

 

If you have procedures and photos, that would be great

d

Hi mate,

I am new here but wanted to share what I did and figure out. It could help you and other guys...

I've just finished my project. I bought B&O Avant 32 type 844x and salvaged the loudspeakers with the amplifier. It took me a couple of hours to figure out what I need to do and how. OK so there is a summary:

1. My Beovision Avant had different amplifier integrated circuits on PCB. (LM1876TF) I checked the data sheet here: http://www.ti.com/lit/ds/symlink/lm1876.pdf

2. I tried to use the original PSU (power supply) with no luck. Even though  I connected P42 pins 2 -> 10 I could measure the voltage, but immediately I connected the amplifier the voltage dropped to about 5V. I did not have time to reverse engineered the PCB. Obviously the power for audio circuit +20V/-20V needs to be turned on somehow. Please let me know if you know how to do it. And yes I tried to poll up the pin 2 on P42.

3. There is no need to use the original power supply board since it is too big and I decided to used old laptop charger (Dell) which was rated to 19.0V and 4 A. I measured the current flowing through and it is actually at most 350 mA. So if you have any power supply DC 20 - 30V about 0.5A and more it will work just fine. Connect -V to blue (pin 1 on P58) and +19V (pin 2 on P58) audio PCB marked as 10 on B&O service manual. I know that it says -20 and +20V but it is not necessary for this particualt IC(LM1876TF)) It does not require the negative charge and it works.

4. Mute pin on P57 needs to be connected directly to P58 pin 2 without any resistor. The current flowing through is only 0.5mA that means there is already some protection. +5V is not enough. I thought it does not work when I tied only +5V,

And that is it. P57 pin 1 is input for right speaker signal, pin 2 is GND, pin 3 is Mute pull it high with the power supply +19V and pin 4 is input signal left.

It works now and it cost me only £10. (that was the price of the TV)

Cheers

 

There are some pictures which corresponds to the stuff I mentioned and did.

This last one shows how I pulled-up the mute pin directly.

gando:

3. There is no need to use the original power supply board since it is too big and I decided to used old laptop charger (Dell) which was rated to 19.0V and 4 A. I measured the current flowing through and it is actually at most 350 mA. So if you have any power supply DC 20 - 30V about 0.5A and more it will work just fine. Connect -V to blue (pin 1 on P58) and +19V (pin 2 on P58) audio PCB marked as 10 on B&O service manual. I know that it says -20 and +20V but it is not necessary for this particualt IC(LM1876TF)) It does not require the negative charge and it works.

 

Sorry to say, but this shows that you have not investigated the datasheet of the LM1876 thoroughly.

This all has to do with balanced and unbalanced in- and outputsignals.

You're right that you can use this LM1876 with only 0 and +20V. But that needs additional parts and different setup, like e.g. an output capacitor to block the dc at the outputstage.

You can use this LM1876 with unbalanced (asymmetrical) powersupply, but with an outputcapacitor. For instance 4700uF. Or you can use it with symmetrical powersupply without the outputcapacitor. And the PCB doesn't contain that capacitor as it wasn't designed that way.

This explains why your current goes up when connecting both grounds together.

To make this PCB work properly, you need a symmetrical powersupply.

This board is also used in the BV5. There are diagrams available.

 

 

Hi,

You are completely right. I was probably drunk or what... It is clearly in the datasheet :D

I will take a look on it properly and thank you for the diagram.

Please could you explain a bit more what is the capacitor good for? You already mentioned that it will stop the DC current at the output. I can even see that in the datasheet (4700uF). I do not have much experience with amplifiers.

Is there a problem if I do not have connected GND? Even if I connect it and measure the current, there is no current flowing through. In my case the current does not change at all if I connect GND.

Right now it works without any problems...

Thank you

Gando

Dear Gando.

I have the same idea as you. And I am wondering how it worked out in the end?

 

Cheers

Andreas

can i use aux output from my television non b&o to feed the amplifire ,ore do i need another signal.

i use 2x dell laptop powersupply as + and - supply