Happy Thanksgiving! We will be closed Thursday Nov 25 through Sunday Nov 28. The website will still be open, so feel free to place your order. Responses will just be delayed until the following week. Thanks!


CCAP_SUB-BR Rectifier Substitution Box

Use: Bridge rectifier substitution.


Bridge Rectifier Substitution Box, Variable Sag to emulate a tube rectifier.

OK, I admit it. You can calculate circuit values until the cows come home but sometimes it’s so much easier and faster to just dial it in. I’ve been a ham and involved in engineering for over 35 years, and I gotta tell ya, these are undoubtedly some of the most indispensable tools I have ever had.

The C-Cap Sub Boxes are full wave or full wave bridge rectifiers with adjustable sag so you can emulate a tube rectifier of a certain type in the development of your high voltage circuit. The C-Cap Sub Box is adjustable from a 5Y3GT to a straight SS (no sag) rectifier and everything in between. For instance, if you determine by the setting on the C-Cap Sub Box that your amp sounds best between the setting of a 5V4 and a 5AR4/GZ34, you can use a 5AR4/GZ34 with a power resistor in series to split the difference between the two. The label on the C-Cap Sub Box indicates the approximate resistance between straight SS through and including a 5Y3GT, so you can do the math easily to determine that series resistor value.

This box is about 1/4″ taller than our copper cap module since it contains a rheostat. It also has two mounting feet on both ends, the same as the copper cap module. It may be installed in an amp permanently and used as an adjustable-sag rectifier.

The only issue is that the rheostat has a wiper and might move some due to the vibration in a combo amp or in a head sitting on a speaker cabinet. You could experience some slight noise or scratching sound if that occurs.


There are no reviews yet.

Be the first to review “CCAP_SUB-BR Rectifier Substitution Box”