It has two less power tubes than my 100w Avenger, but gains an extra preamp tube for the effects loop. This amp design is closely related to the budget Jet City models such as the JCA50 or the JCA22 which I am intimately familiar with - I did my first ever amp circuit mods on a JCA22.
The first Hot Rod amps were basically more budget minded SLO’s, lacking the crunch mode and the large DeYoung transformers that made those amps famous, starting production in 1991 with the single channel 50w model. 100w models came later in 1994, and the plus version, like mine, started in 1995. These were made until 2005 before being replaced with an updated version for 2006, which removed the slave out from the rear and added a depth control to the front panel, sort of combining together the Avenger line and the Hot Rod line into one (aptly named the “Hot Rod Avenger”). There is also a Hot Rod 25, introduced in 2012.
The naming can be a bit confusing, but the original Hot Rod amps had two inputs and a very stripped down 6-knob, single channel design. The plus models added the second channel but sacrificed the low input. The Avengers first came out in 2003, and were similar to the single-channel Hot Rods, with the same two inputs and one channel, adding the depth control, and removing the effects loop along with a few tweaks to the voicing for more aggressive tones. This was during the era of ever-more-complicated multichannel amps, and a sizable number of guitar players really wanted that stripped down amp design, thinking even having the effects loop present negatively affected the tone - I’m not sure I believe that myself, but I’m sure that had a part in influencing the Avenger design.
Anyway, back to the Hot Rod. This is a great sounding amp, with the classic Soldano lead tone - bright, punchy, and extremely clear. It sports all Mercury Magnetics transformers. The “normal” channel also sounds quite good, although it shares the EQ with the overdrive channel so it does have some limitations there. Still, it feels quite natural when switching channels, keeping the same core tone with less gain and a hair brighter with the preamp knob set at half or below. The overdrive channel gets quite gainy but can be a little loose on the bottom end without a boost, but its open character means it’ll take that boost very well. I’ve played it a few times boosted with a Klon Clone and it takes the natural tone of the amp and kicks it into high gear, or alternatively using a Boss SD-1 or Tubescreamer and the bottom end tighten up while the mids get more prominent - great for solos or metal rhythms, especially with lower tunings. Truly a staple of high gain tones, and for good reason - and quite different tonally from its estranged family (Rectos and 5150/6505’s).