Hot Rod Deluxe : Tune Up Time
Over the years that I’ve owned my Fender Hot Rod Deluxe, it’s seen a lot of stage and studio time. I don’t remember exactly when I got this amp; it must have been at least five or six years ago. In general it’s always been a solid performer with a few minor personality quirks: (1) the “red” gain channel is ridiculously overdriven and musically unusable (2) the amp breaks up far too early in the gain stage and (3) the stock speaker sounds like a ham sandwich.
A few years ago I experienced the most common of HRD ailments: the all-too-common cold solder issue with the 5W resistors (#R58 and #R59 on the PCB). It manifests itself as random channel switching and reverb switching. This is typically repaired by simply re-soldering the errant connections, but my local shop tech also added jumpers to help alleviate the overheating on these traces.
The first step for this amp will be a full retube. I have ordered a set of JJ tubes:
- ECC81 ( 12AT7 ) in V1.
- ECC832S in V2. This is a hybrid tube that is an ECC83S ( 12AX7 ) on one side and an ECC82 ( 12AU7 ) on the other side. Essentially this will drop the gain in both the clean and drive channels and increase the headroom.
- ECC83S for the phase splitter.
I’ll install the tubes and fully rebias the amp. Then I’ll install a new speaker. I’ve ordered a Weber Chicago 12 which I’m told is a very nice vintage-sounding speaker with lots of clean headroom. Once the speaker arrives I expect the amp to have a significantly improved clean voice. A post-upgrade report will follow…