the Onkyo A-10 is the big brother of the A-7 and A-5. These were certainly over engineered for their time and have both a heavy aluminum front plate (about 1/8″ thick) and very good quality components and construction.
I have only come across one A-10, and it impressed me a great deal, and effortless sound quality, great detail and solid bass..all with great transparency. I mentioned in an Audio Karma post that I proffered the upgraded version to a Krell KAV300i I have and what were the upgrades etc I undertook.
All the electrolytic caps except the large power supply units (2 x 13kuf 63V) were replaced. Mostly by Nichicon PW low impedance types, however the original circuit had a number of low leakage caps fitted, and these were replaced by Nichicon KL types- except the 2.2uf and lower values, which were replaced by WIMA film types. C275, C276 were replaced with ELNA Simlic II. C253,254 were replaced with Nichicon KZ, as were C311,312. C337,339 were replaced with Nichicon FG.
The 2SA726 were replaced with KSA992, as were the 2SC720. The 2SC1681 were replaced with KSA1845FBU
overall the amp sounded very good, and shows I think a very good underlying circuit and quality components
I recap and upgrade Onkyo A-7s whenever I can find them