Yamamoto HSA-01 headshell/head amp

For the curious, here is the manufacturer's page. ¥72,000 or $458USD.

It says it can be used with almost all arms (taking that headshell), which probably implies that the overall length of the headshell is the same as usual, otherwise it might mean re-mounting the tonearm a little further away from the spindle to cope with the change in effective length. So this little amp is really small, and miniaturisation and op-amps are not always a good thing if sound quality is more important than convenience/price. I'll be interested to hear what you make of it.

Frequency response said to be 10-100kHz. It’s just a tiny gain stage. Within any high gain MC phono stage there is likely a single similar device adding gain at the input. So they’ve in effect surgically removed it and mounted it in the headshell along with a tiny battery PS. The question in my mind is whether that affords an audible advantage. I paid much less in Tokyo due to the favorable exchange rate.

A + plus for battery power! I have a Marcof PPA-1 head amp with battery power for use with LOMC cartridges. One advantage a SS gain stage has over a transformer is extended bandwidth.