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Bridged = Bridged mono.

You wire the speakers in series across the two positive feeds.
Nothing is connected to negative feeds.

There's a diagram on page 12 of the manual.

All bridging does is take the input, feed one channel in phase and one channel out of phase, the two outputs are now out of phase with equal potential. The voltage across the two outputs are now double the voltage across a single output and the negative terminals.

So bridging doubles the output voltage, but not the output current capability, that is why most amplifiers will state they can only drive 8 ohms when bridged, even if they can drive 4 ohms normally.

Steve.

Ahha, thanks for that Steve, so you're saying that, let's say you have one speaker called speaker 1 and the other called speaker 2.

You take the negative from speaker 1 and wire it to the amp, then the positive from speaker 1 is wired to the negative of speaker 2. Then finally, the positive of speaker 2 is wired to the other terminal on the amp.

Is this what you call in series?

Hi Will,

You are correct, that's how it would be wired up.

It is what I call in series, it's also what all the electronics lecturers I had called it.

I think the bridged term is used by Meridian because technically it's correct and Mono isn't.
Mono could seen as a single input driving both outputs at the same time, or two inputs being summed and driving both outputs at the same time.
The Bridged name comes from bridging the two channels with the loudspeaker load.

If the circuits where implemented really well, a real balanced XLR input could be used to feed each channel of the power amp separately, giving a true balanced operation right up to the loudspeaker.

Steve.

I have not got your 557 yet, not until my brother visits in a few weeks. I wont be needing it for a while yet until the HT room is complete.

I am planning to use 2 B&W htm matrix speakers as center speakers, one above and one below the screen, until I can buy a nautilus htm. I understood that two centers give the illusion of the sound coming from the middle of the screen.

You could always put one behind the screen and avoid all the aforementioned pitfalls...
Cheers,

Ed.

This would be wiring your two speakers in series across one output of the amp.
Not a good idea. Speakers should never be wired this way (apart from tanoy PA systems)

If you have a 2 channel amp that can be bridged, the amp is switched to bridged mode and the left and right "Black" terminals are joined together, you then connect ONE speaker across Left RED and Right RED.

So as the signal increases the left RED goes more -ve and the right RED goes more +ve. Double the voltage (and higher current output). ie you have balenced power out to the speaker.

Regards,
Carl.

Putting two speakers in series will double the impedance.
It won't cause any problems at all, especially if the amplifier is bridged, because the voltage is doubled and the impedance is doubled, therefore the current stays the same.

It's not common practice, but there's nothing technically wrong with wiring up loudspeakers this way.
It's what the OP asked for, a way to wire two 'speakers to one amp.

Steve.

Hi Steve,

I think I got the wrong end of the stick, must read more carefully , in my head it was all about wiring to bridged amps.

However, whilst I agree you can wire speakers in series, it's not a good idea sonically esp. for high frequencies, but it`s late and I`m struggling to recall where it read it.

Regards,
Carl.

Would in be better to wire the speakers in series to the bridged amp or use a spliter from the preamp and have two inputs into the stero amp?

Can anyone explain why two center speakers placed vertically above and below a screen would sound inferior to just one?

Two loudspeakers playing the same signal will have a comb filter effect, adding and subtracting at different frequencies. There will also be a lobing effect.

This is worse with horizontal set ups than with vertical set ups.
Do a internet search on MTM (midbass, tweeter, midbass) centre 'speakers, you'll get lots of information on why they aren't ideal.

Having a single centre 'speaker is the best solution, behind a acoustically transparent screen at the same height as the mains would be even better, but below or above would also be good.

Steve.

How easy is it to come by acoustically transparent screens? Are they the majority or minority?

N

Very easy, but very expensive. The material is extremily technologically complex. I've just installed one at my parents house. Screen Research 2.4m across, inset into the ceiling and electric. �4k roughly. Stewart Filmscreen are even more. Easily available, but not the norm because of the price. Screen Research is US and was built to order and imported by the UK rep.

I couldn't find the same product type available for less money. Only the top-end firms do accoustically transparent electric screens. But maybe, for a fixed screen you could spend a lot less. You just need to build a frame, buy the material and tension and align it. Not as easy as that makes it sound!