General Forum

Re: unusual setup: select 2 out of 3 Beolabs

Steve at Sounds Heavenly — Tue, 16 Feb 2010 15:56:38 GMT

Hi js,

Here's an alternative idea that may help you:-

If position "B" is for serious listening, using speaker 2 for left and speaker 3 for right, why not invert the speaker connection for speaker 1 to simplify the wiring?

When listening from the "serious listening position" (position B) this gives correct stereo signals. When listening from the "background music position" (position A) this would give right channel sound from speaker 1 (left speaker) and left channel sound from speaker 2 (right speaker) - almost indistinguishable from the real thing unless you are listening carefully!

Then all you need is a simple two-way rocker switch in a little box fitted to the Powerlink cable feeding speakers 1 and 3 which alternates the "Powerlink Mute" trigger signal between either speaker 1 or speaker 3 depending on the listening position.

I would be happy to look at putting together a suitable switch box for you, making this an easy "plug and play" solution.

Kind regards,

Steve.

Re: unusual setup: select 2 out of 3 Beolabs

cooldude — Tue, 09 Feb 2010 14:19:52 GMT

js:

Burantek, thank you, I appreciate your creativity.

Cooldude, thank you as well for the switch box idea. I originally thought that switch boxes only worked with passive speakers (i.e. two-wire cables): do you confirm that these will work with active speakers as well? Can these work with low level signal (i.e. lower than speaker link level). And how do you use these with four-wire Powerlink cables (or eight-wire cables if I ever switch to BL9), i.e. wich wire(s) should go through the switch box:

- the right channel signal wire (pin 5) and the ground wire (pin 2): in this case the inactive speaker will not receive the right channel signal so it should remain silent, but it will not remain in standby because it will be triggered by the loudspeaker relay wire (pin 4).

- the loudspeaker relay wire (pin 4): I don't know how this signal works: is there a continuous signal when the speaker is active (in this case, a switch box could easily activate/disactivate the speakers) or is there just an impulse when the speakers have to go in / out of standby (in this case the switch box will not help)?

Another idea would be a simple DC power cable switch, but I guess this is not an option?

Anyway, it may be safer to inquire about the Sounds Heavenly Powerlink switch box that you mentioned.

Many thanks to you all for your ideas, js

The box in Burantek's last sketch has to be a line level switch. They do exist.

B&O speakers need either powerlink or line level connections. Both work the same way. Difference being that with powerlink the beomaster tells the speakers to switch on or off. With line level the speaker senses when something is sent through the cable and will switch on and it will switch off after it doesn't receive anything for a couple of minutes. Therefore the line inputs don't need a 'trigger' signal.

You can get a din line out straight from the Beosystem9000. (for Beosound 9000 you need a cable powerlink to din)

Re: unusual setup: select 2 out of 3 Beolabs

js — Tue, 09 Feb 2010 14:06:53 GMT

Burantek, thank you, I appreciate your creativity.

Cooldude, thank you as well for the switch box idea. I originally thought that switch boxes only worked with passive speakers (i.e. two-wire cables): do you confirm that these will work with active speakers as well? Can these work with low level signal (i.e. lower than speaker link level). And how do you use these with four-wire Powerlink cables (or eight-wire cables if I ever switch to BL9), i.e. wich wire(s) should go through the switch box:

- the right channel signal wire (pin 5) and the ground wire (pin 2): in this case the inactive speaker will not receive the right channel signal so it should remain silent, but it will not remain in standby because it will be triggered by the loudspeaker relay wire (pin 4).

- the loudspeaker relay wire (pin 4): I don't know how this signal works: is there a continuous signal when the speaker is active (in this case, a switch box could easily activate/disactivate the speakers) or is there just an impulse when the speakers have to go in / out of standby (in this case the switch box will not help)?

Another idea would be a simple DC power cable switch, but I guess this is not an option?

Anyway, it may be safer to inquire about the Sounds Heavenly Powerlink switch box that you mentioned.

Many thanks to you all for your ideas, js

Re: unusual setup: select 2 out of 3 Beolabs

burantek — Tue, 09 Feb 2010 13:50:41 GMT

Using switch...

Re: unusual setup: select 2 out of 3 Beolabs

cooldude — Tue, 09 Feb 2010 13:21:44 GMT

Problem with attenuated cables they have only one use and mostly are custom made.
They should work, however make sure you switch down the volume before plugging in the headphones......

The A/B switch is fairly cheap and simple to install and use (got mine from Home Depot I think).
The speakercraft box works totally automated (mine was installed by B&O in my setup)
It has channel autosensing with variable sensitivity and variable delay (to kill the switching noise)
All cables used are regular and cheap with rca plugs. (plugs cut off to connect to the switch)

Re: unusual setup: select 2 out of 3 Beolabs

burantek — Tue, 09 Feb 2010 12:58:08 GMT

cooldude:
It would work, I guess , if you had passive speakers...however I don't think the headphone output is at line level (correct me if I'm wrong ...)

Actually, Sounds Heavenly's attenuated cables are for using the passive sockets to send a line signal to actives.

HERE

Re: LINE level out of the headphone... ? I was thinking along the lines of the above cables as well?

Hmmm...

I do like the switch idea and have some loose schematics for that as well... (taking another look). It *could* preempt having the headphone jack around the front...

Re: unusual setup: select 2 out of 3 Beolabs

cooldude — Tue, 09 Feb 2010 12:49:15 GMT

@Burantek

It would work, I guess , if you had passive speakers...however I don't think the headphone output is at line level (correct me if I'm wrong ...)

Re: unusual setup: select 2 out of 3 Beolabs

cooldude — Tue, 09 Feb 2010 12:41:32 GMT

http://www.amazon.com/Dayton-IWS-AB-Wall-Speaker-Switch/dp/B0002KRA9M/ref=pd_bxgy_e_text_b

This switch will select one pair or another pair of speakers.

There will be one speaker that will have two pairs of cables .

This unit connects to both pairs of cables and will switch automatically:
http://www.buy.com/prod/speakercraft-ctl02001-line-level-audio-a-b-switch/q/loc/111/204226662.html

This way you can avoid the reversed L/R channels

Re: unusual setup: select 2 out of 3 Beolabs

burantek — Tue, 09 Feb 2010 12:39:27 GMT

The thread is starting to pick up!

I retreated a bit from my idea of the switch, here is a first rev using just cables... Probably won't work!

Using BC9500, SPK1 that mutes when a headphone jack is inserted, Sounds Heavenly attenuated cables (2 pin DIN -> LINE/RCA), and few other off-the-shelf and/or custom made by Sounds Heavenly... all BL 8000's set to LINE. ZONE A runs on SPK1. Plug the jack in, ZONE A mutes and up comes ZONE B.

Rube Goldberg is either laughing or rolling in his grave!

Re: unusual setup: select 2 out of 3 Beolabs

cooldude — Tue, 09 Feb 2010 12:15:45 GMT

tournedos:

cooldude:

The left channel is always on so should be connected from the audio master to your speakers directly.

The Right channel needs to switch and that's what the box would do for you.

Correct - if you don't care about left/right being reversed in one of the listening positions.

If you do, still all this magic box needs to do is alternate the "power on" signal between speakers 1+3, and reverse the channels for speaker 2. A three pole on-on switch would be enough to implement that. The changeover might not be audibly completely smooth, though...

switch with only right channel connected .... not left (which stays connected directly (powerlink) to the audiomaster)

Worked perfect in my old setup ....

Re: unusual setup: select 2 out of 3 Beolabs

tournedos — Tue, 09 Feb 2010 12:00:09 GMT

cooldude:

The left channel is always on so should be connected from the audio master to your speakers directly.

The Right channel needs to switch and that's what the box would do for you.

Correct - if you don't care about left/right being reversed in one of the listening positions.

If you do, still all this magic box needs to do is alternate the "power on" signal between speakers 1+3, and reverse the channels for speaker 2. A three pole on-on switch would be enough to implement that. The changeover might not be audibly completely smooth, though...

Re: unusual setup: select 2 out of 3 Beolabs

cooldude — Tue, 09 Feb 2010 11:52:36 GMT

Or if you are interested in a more DIY type of thing :

Very easy to switch

http://www.amazon.com/Dayton-IWS-ABDS-Speaker-Source-Switch/dp/B0002KRA2E

Re: unusual setup: select 2 out of 3 Beolabs

cooldude — Tue, 09 Feb 2010 11:46:47 GMT

well I had a setup like it ages ago.

You could ask Steve at Sounds Heavenly (one of the sponsors below) who can make you a powerlink in and out A/B speaker switch box.
The left channel is always on so should be connected from the audio master to your speakers directly.
The Right channel needs to switch and that's what the box would do for you.

It's the easiest solution (just flip a switch on the box).

I had a similar system but had the switch build into the wall for that .... worked basically the same way.

Re: unusual setup: select 2 out of 3 Beolabs

burantek — Tue, 09 Feb 2010 10:54:18 GMT

js:
There exist selection boxes for passive speakers indeed, but I am not sure how to implement that with Powerlink cables.

Well, my approach is that it is just a "dumb" switch. BL8000's don't require fully pinned PLink cables... so you would only have to accommodate 4 wires through the switch -just what it can handle. Split the wires to mount the switch in the middle of the run. This should work fine for SPK1 and SPK 3. SPK2 is the one I am working on as I have time. More later!

Re: unusual setup: select 2 out of 3 Beolabs

js — Tue, 09 Feb 2010 10:43:19 GMT

burantek:

A quick observation: SPK1 is always LEFT, SPK 3 is always RIGHT. SPK 2 is the challenge I am working out.

Actually, listening position B is for serious listening, while listening position A is more for background music when reading. Therefore, I don't care if left and right are inverted in listening position A.

So speaker 2 may remain as permanent left speaker, and one just needs to be able to select either speaker 1 or speaker 3 as right speaker. This should make things much easier I guess.

There exist selection boxes for passive speakers indeed, but I am not sure how to implement that with Powerlink cables.

Many thanks, js