Thought you were counting by number of records the amp is on?
Yeah, that’s one way of determining it. You could also just look at the number of GREAT sounding examples of it, rather than just sheer volume. Believe me, I’ve tried looking for the best examples I can find of SLO tones and there ain’t a lot to pick from.
With that criteria, one could say the Plexi wipes its butt with the Rectumfrier (I mean, since you're making a point of it).
If you want to yeah. The SLO and Rectifier get brought up a lot together because the preamps share a lot of similarities (!), and also they were released within a few years of each other.
The era Plexi’s were from….. there wasn’t really a ton of options for anything else, a lot of guys used them because that’s what was available and they were loud enough to do what they needed. There’s enough guitarists from that era who say they hated their tone, but that’s all they had. Absolutely one of the most influential and important amplifiers of all time though, who’d dispute that? If someone wants to say it’s the greatest, I wouldn’t argue it. Certainly on a lot of records. In 2024 they still probably get used on more albums than an SLO, although I couldn’t really tell you who is using them these days.
Here’s another way of looking at it. Amp circuits progressed something like this:
Early Fenders>Bassman>JTM45>JMP100>JCM800>SLO>Rectifier
Has any new amplifier influenced music to a similar extent since the recto? The kind of amp where you turn TV or a festival on and everyone’s using one? The recto was the last new amp that took over the world like that. Out of those, SLO probably had the least cultural impact and reach; its influence is more on amp design than music made with it.
Great amps have been released since, but none that have really shaped music in a massive way. Things like Diezels and JVM’s wouldn’t exist without Rectifiers paving the way for multichannel, multi-mode amps - but they’re kind of small fish by comparison.
Side note; I think i’ve read people calling it a “Rectum Fryer” for like 30 years. Was that ever funny, aside from when you’re 14 and you hear it for the first time?
I did a thread at Rig Talk a while back trying to collage the best SLO tones. A few gooduns but overall slim pickings.