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.


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

Dear @lewm  : That's not a new idea, many years ago appeared in the market but with no true success. Rigth now I can't remember the manufacturer but if I remember ( ? ? ? ?  ? it came together with the cartridge. ( Can't be sure. )


Regards and enjoy the MUSIC NOT DISTORTIONS,


Dear Raul, you are an amazing historian of this hobby. I personally do not recall any similar product, but if you say it existed, I believe you. However, I would think that a modern iteration of the product would likely be superior to anything that Was on the market 20 or 30 years ago, simply because the gain devices we now have available are both smaller and superior in performance to anything that was possible back then. This does not necessarily mean that the thing I bought in Tokyo will be a revelation. I will report eventually on its performance.  my reason for starting this thread was simply to find out if anyone here had already heard the device in action. 

I heard a fet based front end mounted at the headshell end designed and built by Peter Suchy in the mid 80's at CES. Only difference was that he ran an external power supply with wires running through the arm tube. I never saw this go into production though.

In fact in Japan there have been a number of these head shell based gain stages through the years. This one is one of the tidiest implementations I've seen.

If they had mounted it on top of the head shell there would have been no cartridge limitations.

Of course in the old days Ortofon had mini SUT's built into their low output cartridges in their integrated head shell with some models.