AliEx amorphous, Hashimoto HL20K6 + Sony TamRadio line output transformers

L>R: 6AH4 + AliEx, 12B4A + Sony/Tamradio and 6AH4 + Hashimoto HL20K6

The last time I saw my buddy J-Rob was pre-COVID, but we keep in touch via email and text messages. During one of those hello/how you doin' moments, the chat progressed to line preamp transformers and how the $100/pr. amorphous jobs from AliExpress perform. 

I used to own a pair of Tango/Hirata NP216N nickel line OPTs, which were featured in my Sound Practices issue 17 homebrewer article. In hindsight, I don't think I gave them a fair chance so this was a good opportunity to revisit the topology.

Two RCA derived octal phono preamps

Keen-eyed readers and visitors to my YouTube channel may have noticed the two octal phono preamps I've been using in my recent uploads. I built them for the following reasons:

1. Although the Loctal EAR 834P had no problems driving the Intact Audio nickel autoformers, the 5k Ohm output Z of the Shure M65 phono preamp sounded very anemic.
2. In the spirit of not leaving stones unturned and my curiosity for other sonic flavors notwithstanding, I looked back to passive RIAA EQ phono circuits I've been wanting to build, which have low enough output impedance to drive an Autoformer Volume Control.

Finemet FM-ATVR1 + Intact Audio Nickel 28-step Autoformer Volume Control