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.


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

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.



My rationale for giving the HSA-01 a go in my system is purely to see how it works with the Ortofon MC2000, which puts out only 0.05mV at standard velocity. So far, the MC2000 works well with a head amp built for me by Dave Slagle, driving my much modified Silvaweld 550 in MM mode, and with both my modified Atma-sphere MP1 and Raul’s 3160 Phonolinepreamp, set for hi-gain. Using the HSA-01, the MC2000 output goes from 0.05mV to 0.7mV at the headshell. I want to try it driving either of those latter two phonolinepreamps, with input Z set to 47K ohms. This would say something about the negative effect if any of the wires and connectors between the cartridge and the phono inputs on such a tiny signal amplitude. (Well, we know wires and connectors can have negative effects, but are they ameliorated with a higher voltage output from the headshell?) Also, the HSA-01 would enable me to use the MC2000 in my Beveridge system, which is driven by a Manley Steelhead that only manages 65db total gain at max.

Dear @lewm : You are rigth today op-amps are way better that the ones in the 80’s.

I’m with you that bougth it more by " curiosity ".


" will be a revelation ". I think not because it has very limited frequency range ( I can’t understand why is that but was what Yamamoto choosed. ) and you don’t know its levelnoise that I magine should be low but we don’t know.

Normally headamps has a frequency range from 0.5hz to over 500khz and some -3db at 1Mhz, this is another history and not a " open door " for this thread.


Yes, share with us what you experienced with.


If you say so.  But I personally would not call flat from 10Hz to 100kHz "limited".  If you use -3db limits, then perhaps the bandwidth is much wider.

Can someone please tell me what a SPU cartridge is?  I know it comes mounted on a headshell but what am I missing?

Stereo, you ask what you are missing. What have I written that has anything to do with an SPU, which cartridges are an Ortofon product?

@lewm   I asked because you were talking about a gain stage inside the headshell and I thought that was what a SPU may be, so I asked to be sure.  Sorry if my question upset you. 

No it did not upset me, and I apologize for any sarcasm. I now see how you might have been confused, because the SPU cartridges are built into a headshell, whereas the Yamamoto headshell only has a gain stage built into it. You have to install your LOMC of choice in order to use the gain stage/headshell. I might have triggered your confusion by mentioning that I want to try the Yam with my Ortofon MC2000, which is not an SPU but is an Ortofon product. I bought the Yamamoto out of curiosity regarding whether adding gain ahead of clips, tonearm wires, connectors, etc, which all add resistance in the signal path that could compromise a very low voltage signal might enhance the SQ of a very low output LOMC by increasing the amplitude of the signal voltage at the source. (Sorry for the long and complex sentence.)

Dear @stereo5  : Obviously with all respect.You arrived to Agon in 2008 and you have 6,283 posts that are a lot and that could means you were/are participating in hundreds of threads in the forum.

So, it is weird that from all those years you never had the opportunity to read any of the over 850 SPU references/posts in Agon.

Nothing wrong with that,only that the SPU cartridges are perhaps the most famous Ortofon cartridge models.

Never mind, it's just that I was thinking " loud " in that issue. Sorry.



SPU - Stereo Pick Up.

STEP 1 - Turn on computer

STEP 2 - Click on G O O G LE 

STEP 3 - key in SPU C A R T R I D G E 

STEP 4 - hit the E N T E R button

Takes about 4 - 5 seconds

@rauliruegas .  It was a spur of the moment post as I thought the gain amplifier was part of the SPU and did not know that it was an Ortofon product.  I thought everyone made them at one time or another.

@stereo5 : I think that the Ortofon SPU models were the first integrated cartridge that appeared in the market and that in the latest times we can buy in stand alone version ( some models. ) too.

Through the years other cartridge manufacturers did it the same and in no one of theirs cartridges came with head-amp integrated. Some of those manufacturers were/are ( as Ortofon some models came too in stand alone version and even in plug-in version. ):

EMT,Audio Technica, Fidelity Research, Sonovox, Glanz, Goldbug, Sony, Ikeda, Signet, Grace, Audio Note,Yamaha, Technics, Thorens, Acutex, Dynavector, Azden, ADC, Shure, Nagatron, etc,etc.


If we are willing to do the Audio World gives us the opportunity that every day be a learning day for any of us.




Here is my report on the Yamamoto HSA-01 self-amplifying headshell, used so far only with the Ortofon MC2000: Don’t do it. There is too much hiss or white noise at SPLs even below satisfactory. I suspect this may be because Yamamoto says in the fine print that the device is to be used with cartridges having at least a 0.1mV output at 1kHz at standard velocity. As the cognoscenti may know, the MC2000 does not meet this criterion; its output is only .05mV at the above conditions. Sound quality is very good, but the hiss is unacceptable and would be so to any of us. When I get around to it, I will mount some other higher output LOMC cartridges in the HSA-01, to see whether my hypothesis is correct, that the MC2000 output cannot adequately drive the op amp in the HSA-01. In case you are wondering, I did replace the OEM battery in the HSA-01 empirically, on the premise that it may be worn down just due to aging on the shelf before purchase. Indeed, my measurements of the OEM battery suggest that was worth doing, but to no avail as far as performance with the MC2000. C’est la vie.

@lewm Sorry to hear the experiment did not work out. But fortunately you have a combination of equipment that allows you to enjoy the cartridge. The MC2000 is unique in the challenges it presents, but the beauty of the cartridge is quite the experience even today. Yes, other cartridges may technically have surpassed it, but there is a refinement and gracefulness to the upper registers that few cartridges can equal. The bottom end definition is quite a treat also. I am fortunate that the T2000 transformer and Esoteric E-03 phono stage work well together and the noise floor I have is quite low. I do have to give an extra twist to the volume control, but the system noise is not noticeable unless you stand right on top of the speakers and turn things up to where a low bit of noise leaks through. When listening to music it is essentially a black background. I don’t know if I can ever divorce this cartridge, as it is just too compelling. I always enjoy reading about your experiences with it.

With Dave Slagle’s head amp driving the MM stage of my Silvaweld phono, there is no problem at all, and it sounds great. With my modified MP1 and with the 3160, I get good results but with a very slight sense of strain. On LPs with inherently high gain and low noise, those two work fine. I wouldn’t be putting in the effort if I didn’t also feel that the MC2000 is special.