Penultimate Zen Power Supply

[kilowattski]

I have posted this question before without an answer, but I am building the Zen V4 and using the unregulated power supply shown in the article on the Pass DIY site. There is a bridge rectifier used to isolate the grounds between the two channels on the power supply schematic. Is this bridge rectifier absolutely necessary? What would be the consequences of leaving it out and making the analog grounds of both channels common.

[joensd]

The bridge rectifier connects ground to the chassis.
There are other methods you could use (for example 10Ohms NTC from ground to chassis) but I´d definitely tie them together somehow. More suggestions are here. Just look for articles about grounding amplifiers or power suppplies in general.

The ground of both channels (not AC-outlet earth) are tied together anyway the suggestion being to connect them at the speaker outputs.
Just reread the article and you´ll find the passage.
It´s on page 4 and starts with "If you construct...".
If you use only one transformer you only have one ground for both channels anyway.

Hope I got you right (and you me?).

Cheers
Jens

[kilowattski]

Jens,

Thank you very much for the link. After reading the Elliott Sound Products article on grounding, it has become crystal clear to me why that bridge rectifier is absolutely necessary. Thank you very much for drawing my attention to it.

[jackinnj]

and to Kilowattski -- "what hump?"

[Nelson Pass]

Originally posted by kilowattski
... it has become crystal clear to me why that bridge rectifier is absolutely necessary...

You can just ground everything, but sometimes you end up with
some noise. With the Zen amps, this is not as much of a problem
as some others because their gain is pretty low anyway.

BTW, Kilowattski, where did you get Cyclotron guy's picture
and does he know you're using it?

[kilowattski]

Thank you for the reply Nelson. I saw no reason why I could not have just grounded each channel. What I really feel foolish about is that ground loops, hum and noise never entered my mind, whats left of it. After reading the article on the link that Jens posted I felt like a real schmagegge.