The shown transformers are custom made by Muse Coils (Alexander Naydenov) and feature his signature: 90% snake oil and 10% measurements. Don't let this mislead you, these measure very good but are built using all kind of materials with one great goal: to add tone. Me like. They also look a bit posh, way different from most transfomers. Me like.
As said, custom made. Goal was to make a preamplifier with the RS282 as voltage amplifier. Just curious what it would do as they perform might well in the power amplifier. Transformer specs are 24K:600R, primary inductance 98He, primary dcR 83R and secondary dcR 2.5R.. Only 10% measurements my ass. This is impressive!
And they are huge! These line-out transformers outweigh and measure way bigger compared to most output transformers! Time to hear if Menno vander Veen is right: the bigger the core the better resolution. And he is.
When built and tested it measured perfectly up to ~60Khz and all the way down to 2Hz.
Below a picture with the power supply in the background, It just fits under the shelf, 34cm standing tall!
Soon an article on building this preamplifier.