B&O Beovox S45-2 help

What people are working on at the moment
Post Reply
jonty
User
Posts: 9
Joined: Fri Mar 31, 2017 7:35 pm

#1 B&O Beovox S45-2 help

Post by jonty »

Sorry to jump right in on my 2nd post here and ask for advice, but this seems the place to ask.

I picked up a pair of B&O Beovox S45-2 speakers today for the eye watering sum of £10.
They’re a little bit scratched but otherwise look decent enough and should clean up fairly well. The one that does work sounds to my ears pretty damn good.
The reason they’re so cheap was the bass driver in one isn’t working (although it does when the source is added direct the the speaker) so i guess the fault lays within the crossover?
Is it just a case of replacing the caps?
I have zero knowledge whatsoever of speaker repair in any shape or form, so as the thread title says…
Help!

Pics of speakers and crossover..

Image
Image
User avatar
shane
Social outcast
Posts: 3403
Joined: Sun Sep 16, 2007 12:09 pm
Location: Kept in a cool dry place.

#2 Re: B&O Beovox S45-2 help

Post by shane »

Hi and welcome!

Not bad for a tenner, certainly and if the bass unit of the non functioning speaker works when connected directly, then it shouldn't be hard to get it working.

You're right to suspect the caps, although it's possible that a resistor could have gone o/c. The inductors are unlikely to be faulty. You can check the inductors and resistors with a multimeter. If they're all ok then it's a cap, but to be honest you'd do well to replace the caps anyway as they're likely to have drifted out of spec over the years.

Of course, as an NVA fan, you might want to look at Dr Bunsen Honeydew's thread on speaker mods, there are some interesting ideas there, and you've only got a tenner to lose!

http://www.audio-talk.co.uk/phpBB3/view ... f=4&t=6693
The world looks so different after learning science. For example, trees are made of air, primarily. When they are burned, they go back to air, and in their flaming heat is released the flaming heat of the Sun which was bound in to convert air into tree.
jonty
User
Posts: 9
Joined: Fri Mar 31, 2017 7:35 pm

#3 Re: B&O Beovox S45-2 help

Post by jonty »

Thanks Shane.
I'll do as you say ref the testing and go from there, but i'd like to get used to them before any modding begins.
I've never repaired a speaker before, so it should be a steep learning curve :shock:
User avatar
Dr Bunsen Honeydew
Old Hand
Posts: 1358
Joined: Mon Sep 21, 2009 10:50 am
Location: Muppet Labs

#4 Re: B&O Beovox S45-2 help

Post by Dr Bunsen Honeydew »

Well you know what I am going to say but I might as well say it anyway.

1 remove wadding
2 throw away the crossover
3 steel line the cabinet
4 dope bass and mid drivers or replace with Doc Mod doped drivers.
5 bass and mid driver wired in series direct to input sockets
6 Tweeter with 3.3mfd cap and 12 ohm resistor

Enjoy.
jonty
User
Posts: 9
Joined: Fri Mar 31, 2017 7:35 pm

#5 Re: B&O Beovox S45-2 help

Post by jonty »

i'm not sure the mid can take any more doping, its on pretty thick as it is, as my cat found out when she stuck her nose in it :shock:
User avatar
shane
Social outcast
Posts: 3403
Joined: Sun Sep 16, 2007 12:09 pm
Location: Kept in a cool dry place.

#6 Re: B&O Beovox S45-2 help

Post by shane »

I wondered how you dealt with 3-ways. Bass and mid in series is a bit alternative!
The world looks so different after learning science. For example, trees are made of air, primarily. When they are burned, they go back to air, and in their flaming heat is released the flaming heat of the Sun which was bound in to convert air into tree.
User avatar
Dr Bunsen Honeydew
Old Hand
Posts: 1358
Joined: Mon Sep 21, 2009 10:50 am
Location: Muppet Labs

#7 Re: B&O Beovox S45-2 help

Post by Dr Bunsen Honeydew »

Oh! yes it can, did you see the thread about the Marantz 3 way at HFS.

http://www.hifisubjectivist.org/viewtop ... 17&t=48285

Image
User avatar
Dr Bunsen Honeydew
Old Hand
Posts: 1358
Joined: Mon Sep 21, 2009 10:50 am
Location: Muppet Labs

#8 Re: B&O Beovox S45-2 help

Post by Dr Bunsen Honeydew »

shane wrote: Fri Mar 31, 2017 10:27 pm I wondered how you dealt with 3-ways. Bass and mid in series is a bit alternative!
Why
User avatar
shane
Social outcast
Posts: 3403
Joined: Sun Sep 16, 2007 12:09 pm
Location: Kept in a cool dry place.

#9 Re: B&O Beovox S45-2 help

Post by shane »

Only because most 3-ways aren't wired like that.
The world looks so different after learning science. For example, trees are made of air, primarily. When they are burned, they go back to air, and in their flaming heat is released the flaming heat of the Sun which was bound in to convert air into tree.
jonty
User
Posts: 9
Joined: Fri Mar 31, 2017 7:35 pm

#10 Re: B&O Beovox S45-2 help

Post by jonty »

After a bit of light reading and a closer inspection of the drivers it appears that the non functioning one is seized (which apparently is very common).
So rather than trying to source a 2nd hand unit and run the risk of it happening again I may as well go the Doc mod route, which will at least save me messing around with the caps etc.
In the mean time, i'll have a bash at tidying up the cabinets.
Post Reply