Yamamoto HSA-01 headshell/head amp


During my recent trip to Tokyo, I happened upon this gadget. It is a headshell with a built-in gain stage that boosts signal voltage in the ratio 1:14. Apparently this is achieved via a tiny op amp and battery power, both seated in the base of the headshell, behind the phono cartridge mounting area. The beauty of the idea is you can thus boost the signal of a very low output LOMC right at its source, before it has had to travel over connectors, tonearm wires, more connectors, etc, to reach the first stage of gain, be that a head amp, SUT, or high gain phono stage. The op amp is designed to drive a 47K ohm input resistance and is thus suitable for MM stages or a low gain MC stage in which the load is 47K ohms. The net weight is only 12.5g, making it somewhat compatible with even high compliance very low output cartridges. I wonder if anyone has experimented with this gadget. I am about to do so myself.

lewm

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. 

Looking forward to your thoughts after you get to spend some time with this piece in your system. Enjoy the music