I was a MiniDisc guy back in its day. I still have a MZ-N1 portable recorder in great condition, but I sold my deck many years ago. The N1 managed 50+ hours of battery life. Try that on an iPod.
I KNOW!!! Sony's efforts at long battery life (didn't they brand it "Stamina" or something) were amazingly successful. I remember one cassette Walkman they made in the 90s that could run 37h off a single AA alkaline. When the original iPod came out in 2001 with its 10h of playback on a charge, I remember thinking "Man, if only Apple could leverage Sony's power management expertise!". Or, like, let Apple design the enclosure and the software, and let Sony design the hardware innards.
And there is precedent for that: Apple's first battery-powered Mac was the awesomely quirky Mac Portable, which was a luggable whose weight was the same as a Mac SE desktop (just with a sealed lead-acid battery responsible for the weight instead of the CRT). Apple's first round of actual laptops was the
100 series. It comprised the PowerBook 140 and 170, which Apple designed entirely in-house, but also the smaller PowerBook 100, which was actually
built by Sony, who was given the Mac Portable schematics and asked to make it little! (Though it was released at the same time, the PowerBook 100 was actually designed later than the bigger models, so its aesthetic is somewhat closer to later PowerBook models, like the Duo series.)
Of course, in the intervening 15+ years, Apple has improved its power management dramatically. But it's clear that the iPhone series was what really gave them the push they needed to invest in this.
The STR-DA4ES (or DA7ES) receiver may be suitable for your system. Two tape (in/out) loops plus two more video loops, so plenty of analog line-outputs for recording purposes. It has Control-A1II and Control-S jacks, and supports two-way remotes. It also has two multi-channel audio inputs (5.1 and 7.1) and 7.1 pre-amp outputs. It's becoming harder to find those these days. One downside is the use of SAP15N (and -P) transistors for amplifier output devices. These have a built in emitter resistor as well as temperature-compensated biasing circuitry, and they are no longer made. That makes repairs more difficult if ever necessary.
Cool, thanks for the info, I'll keep an eye out!!!