Grounded Bridge Question

[rtarbell]

I was curious about the grounded bridge concept from Crown Audio.

I'm sorry if this question has an obvious answer; I downloaded the white paper and it's still not obvious to me:

In the grounded bridge configuration, you have two pairs of output transistors, one pair is inverted from the other. For the output pair that is driving the load on the grounded side, what makes the current go through the speaker and not directly to ground? Does the answer have something to do with the floating reference of the output stage?

[Jan Dupont]

Hello rtarbell,

I have studied this whitepaper earlier, and it's quite simple

As symbilised by the battery, the Grounded bridge uses a single supply (and not dual as in common amps). In this case the "ground" is virtual, and can float from 0V to the +supply Voltage. With no input the "ground" will rest at ½ supply Voltage.

The only difference between this Grounded bridge and normal bridged amplifiers are, that you can save som money by using only one single supply.

I hope this have halped you, other whise just ask

[SpittinLLama]

For the life of me I cannot find the white paper on Crown's site. Do you have a link for it? First I have heard of this and am interested in how it works or what they mean. A lot of the 'technical' papers on Crown's site are litlte more than technical marketing. Even their Class I is nothing really new and is typically know as PWM Class BD, not Class I. Anyway, a link would be great.

-SL

[Jan Dupont]

Here you go
http://www.crownaudio.com/amp_htm/ampinfo.htm