Hi all, i've just got a pair of Beolab 2500's and i want to use them as PC speakers (3.5 mm jack from Mac) but they don't turn on with out the 8  pin powerlink, is there a way around this? I also have an Ouverture, but i don't want to use it as the master, it would be a waste of a beautiful machine!

 

Dave,

These are Powerlink speakers where pin 4 must be greater then 2.5 volts to switch the speakers on and pin 1 must be greater than 2.5 volts to switch the Powerlink on.

I understand this, cheers, so what could i do to make them work from a 3.5 mm jack? I'm starting to think my only sensible option is to get a beolink active to activate the speakers...

No problem... you have a power supply in your pc. Use a floppy drive plug für the 5V you need to switch the speakers on.

Drill 2 holes in the back of the case or in a slotcard, 2 8pin plugs, some wire and finished. Powerlink installed. 

Ah, i wish i could do that, but it's an imac G4... so that won't be possible.

You could always run it from the USBs which have +5v DC.

I'm not sure whether this is true of both USB 2 and 1.1 or just 2. Which iMac do you have? If it was new from September 2003 onwards, then it'll have USB 2.

Looks like USB 1.1 and 2.0 both carry the same amount of voltage.

However, more accurate sites I've looked at seem to show the USB voltage as being between 4.75 and 5.25v. Can one of our more technical members verify how picky BeoLabs are when it comes to the voltage?

I don't really know much about computers, but it was bought in 2006, 

ah! Thank you, i see, now all i need is to know how to do that, i can see it being a really dodgy and messy clump of wires and sticky tape, i have made a powerlink to single coaxial plug which was easy, but a usb and 3.5 mm plug to powerlink sounds scary, i have bought a soldering iron which would come in handy doing this wouldn't it?

Have you thought about Beoport?  I bought one for the same purpose of connecting BL2500's up and it worked well...although the box is hideous and the cable mess annoyed me but you could still use the Beo4.  I have mine now sitting in a cupboard collecting dust.

Let me start by giving you a word of warning, using the USB +5 volts is fine PROVIDED it is not directly connected to any of the Powerlink pins which I previously stated. It should be connected via a high value resistor. On most USB outlets and powered hubs the +5 volts is rated at 500ma and all you need is a pull-up to raise the voltage above +2.5 volts on the Beolab speakers meaning it needs to draw very low current, this is basic ohms law.

So I suggest if you use this route, you should use at least a 500K ohm resistor between the power and the pull up pin, which means you will need two resistors of at least 500 k ohm.

If you intend to use this approach, I will provide a detailed drawing.

Keith Saunders:

Let me start by giving you a word of warning, using the USB +5 volts is fine PROVIDED it is not directly connected to any of the Powerlink pins which I previously stated. It should be connected via a high value resistor. On most USB outlets and powered hubs the +5 volts is rated at 500ma and all you need is a pull-up to raise the voltage above +2.5 volts on the Beolab speakers meaning it needs to draw very low current, this is basic ohms law.

So I suggest if you use this route, you should use at least a 500K ohm resistor between the power and the pull up pin, which means you will need two resistors of at least 500 k ohm.

If you intend to use this approach, I will provide a detailed drawing.

I think i will leave this option out, as i have no experience in this department, i will surely blow something up... but using a beoport sounds promising! 

PentaIII:

Have you thought about Beoport?  I bought one for the same purpose of connecting BL2500's up and it worked well...although the box is hideous and the cable mess annoyed me but you could still use the Beo4.  I have mine now sitting in a cupboard collecting dust.

I'll send you a PM 

Keith Saunders:

Let me start by giving you a word of warning, using the USB +5 volts is fine PROVIDED it is not directly connected to any of the Powerlink pins which I previously stated. It should be connected via a high value resistor. On most USB outlets and powered hubs the +5 volts is rated at 500ma and all you need is a pull-up to raise the voltage above +2.5 volts on the Beolab speakers meaning it needs to draw very low current, this is basic ohms law.

So I suggest if you use this route, you should use at least a 500K ohm resistor between the power and the pull up pin, which means you will need two resistors of at least 500 k ohm.

If you intend to use this approach, I will provide a detailed drawing.

Hi keith I'd like to give this method an honest try, because quite frankly $600 for a box to connect the speakers to the computer is a waste of hard earned, and i am competent enough with electronics and soldering (just).

Would it be possible to see a diagram of which pin to charge etc? Also, is there a way of covering the resistors so that they don't get pulled or torn while it's in use?

Thanks so much i appreciate the advice 

Hello Keith,

Would you mind supplying me with the detailed drawing?  I too would like to use my BL2500's as computer speakers, but the red light won't turn green, I guess until I get a 5V line to them.  My email is rwilger@hotmail.com

Thanks in advance.

Richard

Also, there's a beolink active for sale on eBay for $200.  Might this be an easier and cleaner way to take care of this problem?

Or you could just get a beoport (PC office / PC2)they're cheap as chips on lifestyle av's webpage

 

:)

I don't have a B&O system in my office, I just have the active speakers which I was hoping to connect directly to my computer.