DRIWATT – Hiwatt Preamp

While most of Rock hisotry was dominated by Marshall amps, the impact of Hiwatts through out the 70s, 80s and 90s cannot be discounted. Some of the notable Hiwatt players include Pete Townsend, David Gilmour, Jimmy Page, and Canada’s very own, Alex Lifeson. In particular, the tones of Custom 100 DR103 can be heard on famous rock records spanning generations and is sought after by many musicians.

DRIWATT is my take on trying to capture the essence of this legendary amp in a pedal format. The design features JFET’s which are great for emulating tube triodes and includes two separate Normal and Bright channels, as found on the original amps. DR103’s were low to medium gain amps with plenty of clean headroom.

Controls are similar to what one will find on a 4-hole DR103 from that era. Normal and Bright channles are internally jumpered, as preferred by many rock musicians, and can still be individually controlled using the seperate volume control for each channel.
Master: Controls the overall volume

Bright : Volume control for the Bright channel

Normal: Volume Control for the Normal Channel

Bass, Mid, Treb: 3 band Tone stack modelled after Hiwatt DR103 tonestack

Pres: Presence control

Since this is a preamp unit, it can either be used on a pedal board in signal chain as a drive, or you can run it directly into the effects loop of your favourite amp. Another way to use it is to run it directly into your DAW followed by speaker IR’s. Similar to a classic DR103 amp, the gain on tap is medium. You can drive it harder by using an OD in front, as you would with an actual tube amp.

This pedal runs on standard pedal power center negative DC supplies. It can also be run anywhere from 9-18V for more headroom.