Deluxe Reverb race tune-up

We get a lot of questions about modding the Fender Deluxe Reverb to become a bigger amp with more power and clean headroom. It is a very popular amp and flexible since it can take both 6L6 and 6V6 power tubes. With 6L6 you’ll get 30+ watts compared to the original 22 watts. This mod is so simple it’s hardly called a mod. There are a few risks with this mod, though. The 6L6 will draw more filament current from the PT, which you could compensate for by pulling V1 and the V5 tremolo tube, if you’re not using tremolo. Also, you should use GZ34 as rectifier tube since it draws less current from the PT than a 5U4GB. Still you should check the temperature of the power transformer from time to time. Playing it for 5 hours will involve some risks. Now we’ve said that.

You won’t get full 40 watts and a big Vibroverb/Super Reverb/Pro Reverb tone from a Deluxe Reverb unless you install a bigger power transformer. To minimize sag and increase the bass tone, you should also have a bigger output transformer. There are also other things one should or could do with the filter caps and voltage divider resistors. Let’s take a closer look.

The bottom picture on the collage below shows the two 16µF filter caps of the deluxe reverb mounted in parallell, resulting in a 32µF capacitance. The super reverb has two 80µF capacitors in series, resulting in a 40µF total capacitance. Yes we know that capacitors in series and parallel is difficult to understand. Actually, it is simple. It works just the opposite way of resistors. An amp tech will also notice the lack of resistors in parallel with the filter caps in the deluxe reverb. This is why the Deluxe Reverb can be dangerous on the repair bench since the caps can hold 3-400 VDC over a longer period of time. In the Super Reverb those 220K resistors will make sure the caps are discharged in matter of seconds.

deluxe tuneup

The point is. In the deluxe reverb you may simply replace the 16µF caps with 20 µF caps, OR you may switch to the safer Super Reverb reverb design with two 80µF caps in series + resistors. You should also replace the voltage divider caps with 20µF caps to get more ompfh there. And you should replace the two 10K voltage divider resistors with 1K and 4.7K, just like the super reverb. This will increase the power handling in the preamp section, simply explained.