Ampex 350 351 354 Stereo Reel Recorder 10.5" reels

A very unusual version of an Ampex 350 stereo reel recorder. The story goes Ampex engineers, in their off hours, would assemble these machines to answer the demand for a more portable professional stereo recorder for location music recording- clubs, concerts, etc. They packed a 350 transport- unbranded, into a lightweight case with a PR-10 stereo record electronics assembly that was designed for use with AG-500 type transports with 7" reel capacity. I guess Ampex felt the AG500 met this need, but the engineers saw a demand for a equivalent unit with 10.5" reels for longer performances. The AG500/PR10 transport capstan was belt-driven, inferior to the 350 transport direct drive capstan, along with heavy duty reel motors. It was still a beast, the plastic housing just barely supporting the weight of the machine. Also the PR-10 electronics ran hot, packing lots of tubes in close proximity and mounted on a printed circuit board. I installed a cooling fan over the electronics, as I had packed the thing even further by removing the compound electrolytics in favor of discrete units. I don't know if these ever had a model number. I get the feeling they were sort of an under-the-table model. You can see lathe turning patterns in the metal transport panel where the Ampex logo should be. The switches for power, tape speed and reel size tension have no identifiers. I did the alignment multiple times just to make sure it was in the sweet spot. Vintage machines like this are great fun, but a restoration like this always has you bending your ears to make sure you're hearing what you think you're hearing, trying to head off any alignment drift or anomaly at the pass to confirm its been brought completely back to life. I did work like a dog on this one and when I eventually sold it, I felt confident passing it on. I was thrilled I didn't have to ship it, they buyer had a friend who drove it from Dallas to (I think) Atlanta.