B+ CT or Bridge

[Ned]

I am in the process of deciding the specs for my first Guitar amp build. I have decide for a SS supply. I think I would like to use a non center tapped secondary with a bridge rectifier. I am having a hard time finding a PT with no CT on the secondary. Is there a reason for this? should I not use a bridge circuit?

[Enzo]

Just because a tap exists on a transformer doesn;t mean you have to use it.

There is no particular advantage using one approach over the other. In your design, establish what voltage you need, and how much current it has to provide, THEN look for transformers that can supply that. A bridge is four diodes, while your typical full wave with center tap uses two diodes. SO the difference being maybe 18 cents, what difference does it make? And the electrons won;t care.

The two ways need diferent transformers of course. You either need for example 300VAC with a bridge, and 600v CT (300-0-300) for the full wave. But thinking about it, either way you are rectifying 300VAC. Let the transformer tell you which rectifier style to use.


One reason CTs might be more common is rectifier tubes. One almost never will see a bridge made up of tubes. The typical rectifier tube is a dual section one - exactly what you would want a CT transformer for. You don't plan to use a rectifier tube, which is fine, but they are a reason the style is so common. That is just my opinion.

[Dagan8]

Just because a tap exists on a transformer doesn;t mean you have to use it.

This is true. There are also ways to use the center tap as a "half power" source if you end up using the bridge.