Koetsu cartridges. They must be something special.

Koetsu cartridges deliver a warm, rich and “saturated” sound without sounding murky or slow sounding which is not an easy trick to pull off.  The company closed recently but older cartridges can be re-tipped.  My local dealer uses someone in California and is very pleased with the results.  He is sending a prized Allaerte cartridge to be fixed.

Koetsu cartridges deliver a warm, rich and “saturated” sound without sounding murky or slow sounding which is not an easy trick to pull off.

That’s a perfect description @larryi

I used to think they were stupid, overpriced little boxy rocks. Then I actually heard one, and have been a huge fan ever since. I have 6.

One of the problems was that the North American and Euro distributers would artificially amp up the price of "premium" stones (Coral, Blue Lace) versus "base" stones (Onyx, Jade) to segment the high-end of market. The price disparity was much more modest in other markets (Japan, SE Asia). That said, they were all still expensive cartridges, and the Blue Lace I have does in fact sound better than all other stones. The Coral - eh, maybe not so much. Perhaps my Coral needs more burn in, but the Blue sounded amazing from hour #1. Could be some variation from sample to sample, too.

Supposedly Koetsu bought up the whole run / supply of Platinum magnets, which is why other manufactureres don’t use them (only Lyra, in very limited fashion). They are nice sounding magnets, more smooth and creamy sound versus samarium-cobalt and neodymium. Alnico is pretty neat too, though.

I was a Koetsu dealer for many years...they are indeed something special!

But I refuse to believe a magnet has a "sound". The magnet has an effect determined by its properties as a magnet in combination with the properties of the coils and its mass (of the magnet). The coil does not know it is being affected by a platinum magnet; it only knows the strength of the magnetic field surrounding it. I know there are mystiques surrounding the use of samarium cobalt or platinum or neodynium or other magnetizable metals (alnico?) in MC cartridges, but what is the possible mechanism, other than the above, mass, field strength, and geometry (meaning how the magnet and coil are placed in space)? Can someone ’splain me? Anyway, Koetsu cartridges are a matter of taste, as is the choice of any cartridge brand. They used to be characterized as warm and "musical" or rich sounding but some said of the Rosewood series that they were lacking in low bass and high treble. The Rosewood Signature Platinum was said to have corrected that issue with bass and treble, at the expense of having a much lower signal voltage output; I never heard one. Then came later wood bodied models like the various Urushi models and still later the stone bodied models, among which there are additional sonic differences. I have an Urushi and like it very much, but maybe it is not my very favorite LOMC cartridge. Nevertheless it is definitely not lacking in bass and treble response. I’d like to own a stone-bodied model but was unwilling to fork over the moolah. I own about 6-7 other LOMC cartridges, so the Urushi is just one in my stable. Anyway, it is impossible to disagree with Inna when he writes, "It seems that quite a number of Audiogoners have Koetsu, or a few of them." That sentence has its own escape clause.

Koetsu is special indeed! it’s on my hunting list..

https://medialux.blog/2019/07/07/the-koetsu-story-japanese-art-part-1/

https://medialux.blog/2019/07/08/4-koetsu-compared-japanese-art-part-ii/

Do higher end Koetsu sound like better Mullard tubes ?

@larryi 

+1 Nailed it. This is why I own a Koetsu Rosewood Signature. My dealer bought several when he found out they were closing down shop. 

@Lewm wrote: " "It seems that quite a number of Audiogoners have Koetsu, or a few of them." That sentence has its own escape clause."

I read Inna's statement to mean that Koetsu are popular among participants and some have several of them. 

I own two stones- a Jade- which sounded great out of the box, and a Tiger Eye, which was a bit strident for the first thirty or so hours. Both a tad tail down (I can do VTA on the fly but don't mess with it much once dialed in, except for an extraordinarily thick or thin record- most of what I listen to is pretty standard old pressings from the nadir of vinyl- the '70s) and loaded at 100 ohms. The bass has dimension, tone and a filled-in quality that my system seemed to lack with other high end cartridges. It may be a synergy with the arm- an Airline, which really seems to like a low compliance cartridge. 

@whart...Bill, that was my interpretation too.  I have several also.

Yeah, of course I meant that some had a few Koetsu cartridges.

They are no longer made. Is there a brand that has a similar sound signature and is quite good, though maybe not as good as better Koetsu ?

Kiseki makes some really wonderful carts.  The Purpleheart is one of my favorites.

I heard about Kiseki. Dutch designer and they are made in Japan, right ?

Kiseki of old is not the current day Kiseki. 

I have not heard one, but some say thar Etsuro Urushi cartridges are similar.  The bad news is that they are quite expensive.

Re magnets, bizarrely, they do have a sound. If you listen to some Strat pickups with ceramic magnets vis a  vis those with alnicos, you'll hear it pretty quickly. And its not just down to field strength.

Some of the best midrange you’ll ever hear. Defined, full, smooth, exciting, they open up a whole canvas of sound when compared to other cartridges. This, balanced with thunderous bass and ever so delicate and defined treble make them a joy to listen to for hours requiring no effort from the listener. That’s what makes them special. Just my opinion. 

Yo-yo, so you’ve compared two kinds of magnet set up identically in terms of geometry and field strength and whatever other parameters pertain and compared them on the same Strat ( important to use the same guitar both ways)? And listeners agree the sound is different? (Not to mention we’re talking about a guitar pickup not a cartridge.) even if it’s been done, that doesn’t explain a mechanism.

but what is the possible mechanism, other than the above, mass, field strength, and geometry (meaning how the magnet and coil are placed in space)? Can someone ’splain me?

"Dynamic conditions". The magnetic field varies during playback (however slightly), and supposedly the different magnet types have different behaviors in this respect. No that’s not a satisfactory scientific / engineering explanation, but this is sort of analogous to arguing around "all amps measuring below 0.01% THD (or whatever) must sound the same". Now the anecdotes, for which I have a unique one to this topic:

I have 2 Onyxs, one an old 80s/90s short body with samarium-cobalt magnet. I acquired it with original parts, but worn stylus. It sounded absolutely glorious for about 70% or the record, before the stylus showed its age towards inner grooves. I had this rebuilt by Koetsu in 2018, specifically instructing them to keep the original magnet (because I thought this was part of its "magic"). The other is a circa 2000 Onyx Platinum that I’ve heard both in original condition, and after its own 2018 Koetsu rebuild.

I draw the following observations from these examples:

• The Onyx Plantinum (both incarnations) sounds very similar to other platinum models (Coral, Jade, Blue Lace, RSP), with slight differences among them. The Blue Lace is the best one (for some reason), but they are all of similar character.
• The old Onyx in original condition had the most euphonic and least accurate sound. It was glorious, however. Just a pure music machine.
• The new coils & parts (other than SC magnet) put into the Onyx have a brighter, more extended, dynamic and "modern" sound compared to the old coils & parts. Apparently this is "tempered" by the smoother sounding platinum magnets, because that’s its only meaningful difference now from the other Onyx.
• The SC magnet gives about 2 - 3dB higher signal output versus the Platinum magnet of same size. I guess we’d need larger Platinum magnets to compare them at equal-output levels, but that will never happen.
• In hindsight, I would’ve asked for a new platinum magnet with the old Onyx SC rebuild. The platinum magnet and new coils appear to be properly "balanced" for each other.

IIRC people still chase old Lyra Parnassus cartridges to use as a "donor" for its platinum magnet to use in a new Olympus build.

Jonathan Carr, the designer of Lyra cartridges, has praised Mr. Sugano of Koetsu for discovering the use of platinum alloy magnets.  This is particularly interesting because they both like platinum magnets even though they make quite different sounding cartridges.

This just in: platinum is not magnetic. The platinum in cartridge magnets is probably an alloy of Pt and Co, somewhat akin to Alnico (aluminum/nickel/cobalt) where both Co and Ni are magnetic.

I was aware of Koetsu in 1978 through The Audio Critic, who tested one. It was the world's first cartridge to sell for - gasp! - $1000. Peter Aczel said it was the best he'd ever heard. Don't give me that bullsh*t about inflation making that $1K Koetsu worth $4K in today's dollars. There is so little material in any phono cartridge to justify the outrageous prices asked today!

@lewm : Guitar pickups and strings determine the sound of an electric guitar. The body material/shape have no affect. The magnet material and number of coil windings is where the "magic" resides.

@inna 

i recently got an Analog Relax cartridge—manufacturer reportedly used to work for Koetsu. Its midrange is even more immediate than my Blue Lace. Bass is pronounced too. Only problem is it’s a prototype and doesn’t have the excellent tracking noted in reviews of the EX1000. 

Etsuro Urushi..good to know.

No one forces anyone to buy luxury items. Unlike some other things. I have to pay outrageous electrical bills every month, as an example. Now this is hard to walk around, especially if renting. There is a number of people paying $10k+ for cartridges, and custom Brioni suit was about $30k the last time I read about it.

Jason, I just read the long piece on "pickups" in Wikipedia.  Seems there are a few different types and they operate in a few different ways, any set of which could affect the recorded signal in one way or another.  So I would guess it is about as difficult to say what the type of magnet does to the sound from a pickup as it is to say how the magnetic material of a phono cartridge affects its sound.  I am not saying there is no effect; I am only wondering how one would know or how to investigate that effect as an isolated factor.

Given that Koetsu was a family business and its only emplyees were Sugano San the elder and his son who are both now deceased, but nobody else:

Anyone who manufactured cartridges for Koetsu must be manufacturing them from beyond the grave.

One observation for which I don't have an answer- the Jade sounds different than the Tiger Eye on the same system. From what I gather the innards of both cartridges are the same. The difference in the hardness of the stone is recognized, generally (you can look it up under the Moh Scale for each). I don't know how much that contributes-- neither stone absorbs resonance in the same way that something like wood would; and there was the myth that the better motor assemblies were reserved for the upper tier Koetsu but I think its just that, a myth. 

I will probably try Ana Mighty in France when I'm due for a retip; I gather they had some history with Koetsu back in the day. Those Medialux articles posted upstream are a pretty good introduction to the product line; sadly, the company is no more, though I understand why the family opted not to "sell the brand" to a 3rd party-- it would not have been the same. 

It might've been even better, and that's not what they wanted.

I like the sound of the stone-body Koetsus.  Most of my friends who own or are familiar with the lineup prefer the Rosewood Signature Platinum.  It is a matter of personal preference.  Regardless of the science, the cartridges sound a little different.  But, I suspect, a choices made between the types of stone-body cartridges is primarily based on appearance.  I have seen most of the types, and my favorite look is that of the Blue Lace.

I've had a Koetsu Rosewood Signature Platinum for almost fifteen years now. It has been a wondererful treat.

By the way, my local dealer has sent several of his own and customer Koetsu cartridges for repair/re-tipping to Andy Kim in California.  He is very pleased with what he got back.  It appears that Koetsu will live on well into the future thanks to services like this one.  I think it took Andy Kim a couple of week to do the repairs on an Allaerte my dealer sent to him, and the "delay" in receiving back the cartridge was because new parts had to be ordered from Allaerte.  

One thing I would advise for folks considering a retip on Koetsu: Koetsu used an "interface" type mount, where the stylus is fitted through a collar of different (softer) metal, then into a groove prepared in the boron. Glue is added mostly on the other side, opposite the collar. It’s generally a very clean looking mount under magnification, with less glue used. 

I believe there’s a Japanese supplier of the whole boron rod cantilever & stylus with this interface mount (Ogura?), which should be very similar to what Koetsu used. Personally, this would be my preference. The old cantilever can be removed from joint pipe, and the new one can be added in - stylus mount and all. 

When you compare to Euro and USA style tip mounts, they use a lot of visible glue - it either looks like a mound of cement (Benz, Van den Hul) or a clear-ish bubble (Ortofon). 

The interface mount will track closely to what was originally intended by Koetsu. It’s totally the owner’s perogative to try something different (and I do quite like Fritz Gygers), but it’s something to keep in mind if you want to keep your Koetsu as close to original as possible. 

Ana Mighty Sound in France has shown retip work that tracks beautifully with that of an original Koetsu tip. Same with suakimlp.com, in Vietnam. And I believe Joeseph Long (groovetickler) is also easily capabale of this (or anything else you might want). Those are the 3 I’d trust for keeping a Koetsu as close as possible to original performance.

Years ago many reviews indicated the most “musical” cartridge were the Koetsu stone with the Coralstone as one of the favorites.  The stone carts seemed unaffordable so I purchased the Rosewood Sig Platinum.

I was bummed when it was announced the Coralstone was being discontinued without ever hearing it, but I lucked out and picked up a mint Coralstone D for a great price.  Still debating whether to purchase a Ikeda tonearm and SUT to optimize the sound…another rabbit hole

Grado also has a “musical” reputation, tempted to investigate someday 

The Kiseki Purpleheart is known as a musical cartridge and some consider it similar to a budget priced Koetsu.