Please critique my PSU

[sesebe]

Why don't you use 8 bridge rectifiers?

 

[Lee Knatta]

The use of two rectifier bridges is an audiophile fad and does not bring any practical benefit except heat dissipation.
Instead, it only brings shortcomings, among which the interruption of one of the bridges or a secondary in the transformer will lead to a voltage drop on one of the power supply branches and implicitly DC will appear at the speaker terminals.
In the case of a single bridge, the interruption of a secondary in the transformer will lead to the appearance of a large ripple on both supply lines and no DC will appear on the output.
In the case of 2 bridges, if the secondaries have slightly different voltages, the same will be the voltages after rectification and filtering. In the case of single bridges, the voltages will be identical, but only the voltage ripple will increase.
[…]

The argument regarding one supply becoming zero is valid, but this is also true in case a fuse blows, which is far more likely.
Also true that both supplies may have slightly different voltage.

But it seems that the main benefit of dual bridge rectifiers is to avoid saturating the core in case of imbalance. I found an old discussion about this and this contains some valid arguments from Nelson Pass (post #2), which also make sense to me.

https://www.diyaudio.com/community/threads/dual-bridge-rectifiers-in-psu-why.93712/

 

[sesebe]

Fuse after bridge is completely useless. The fuse is put before the bridge to protect the transformer in case a bridge failure, and before the traf to prevent a fire in case a transformer failure. The rest should be electronically protected.
A traf that is to easy to be saturated is a traf that need to be changed and to not be used in applications were saturation do problems.

 

[Lee Knatta]

Toroid transformer cores do saturate easily, but are commonly used in audio applications due to good efficiency and low external magnetic field.

Placement of fuses is difficult. A lot of components could fail. Placing fuses prior to the bridge mandates good management of inrush current to the large capacitors. The transformer is expensive and therefore deserves good protection.