Koetsu Coralstone

[mem916]

My new Coralstone with the diamond cantilever option arrived today. Here are some pictures I took with my USB microscope prior to installing it.

 

[jadis]

My new Coralstone with the diamond cantilever option arrived today. Here are some pictures I took with my USB microscope prior to installing it.

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Nice macro shots! Congratulations!

 

[Ron Resnick]

Congratulations! I look forward to the listening report!

 

[jfrech]

Cool pics ! I too am curious to read about what you hear

 

[ack]

Remarkable pictures and construction! Do you know whether the cantilever is synthetic diamond or not? They appear to drill a hole into it to mount the stylus, really impressive. Would love to hear what you think of the sound.

 

[mem916]

Thanks! I used a USB microscope. It's a DinoLite similar to the one Michael Fremer recommends for setting VTA. Here's a pic of my setup. After I get it broken in I will use it to get serious about setting VTA.

 

[mem916]

I assume it is synthetic diamond but I suppose it could be industrial natural diamond. Yes I'm pretty impressed, not sure how they drilled that hole without shattering the rod!

 

[mem916]

I will post my impressions after break-in and critical VTA adjustments. I reckon it will take 80 - 100 hours to break-in. This cartridge is replacing my "standard" Coralstone which is up for sale on Audiogon at a reasonable price. I priced it to be fair even if sent to Koetsu for a full rebuild immediately even though I feel it has another 1000 - 2000 hrs left until it really needs a rebuild. I made a recording of this cartridge playing the second side of Stravinsky's Firebird (The Speakers Corner re-issue of the Mercury Living Presence SR90226) which you can download in either 24/96 or 24/192 here:

(192)
https://drive.google.com/open?id=0B2ceYgRGBXdbWDd2QVRVTEktVlE

(96)
https://drive.google.com/open?id=0B2ceYgRGBXdbZU9aTWo1dW8wUEU

I would welcome comments from anyone who takes the time to listen. Tonight if I get ambitious I will re-do the recording with the Diamond Cantilever version and post the files. But bear in mind this will be before break-in and before VTA adjustments!

The Koetsu is mounted on a Versa Dynamics 1.2 (with further upgrades).
Phono: Aesthetix IO
Line: Aesthetix Callisto
Digital recorder: Tascam DV-RA1000HD (inputs bypassed, using the Callisto for level controls)
Cables: Purist Audio Dominius and 25th Anniversary balanced.

 

[ack]

In the fourth picture, are we looking down the cantilever at the coils from the stylus tip? What a great shot!

 

[mem916]

In the fourth picture, are we looking down the cantilever at the coils from the stylus tip? What a great shot!

Yes. I forgot to take a pic from the other direction. When I take it off my turntable tonight I will try to get that shot. I want to listen to my old (standard Coralstone) cartridge and the new one back to back even though this one is not yet broken in and I haven't set VTA critically.

 

[mem916]

I will try to give some initial impressions but it is not broken in yet. That usually takes about 80-100 hrs of play time.

Congratulations! I look forward to the listening report!

 

[rockitman]

Nice !!! excellent shots...Careful with that cantilever. I own two Coralstones...probably my favorite cart...but I'm using boron for the cantilever. Do you have another stone body koetsu with a boron cantilever ?

 

[ddk]

I assume it is synthetic diamond but I suppose it could be industrial natural diamond. Yes I'm pretty impressed, not sure how they drilled that hole without shattering the rod!

They didn't drill a hole, looks like a diamond coating and not a real diamond cantilever as suggested by the branding. I think that Dynavector also has cartridges with the same cantilever type. I recognize the advantages of using diamonds for their optical and thermal qualities, a probe of some sorts or as a protective coating when needed but does anyone know why you'd want a diamond coated cantilever in this application?

david

 

[mem916]

I have never seen a diamond coating that allowed you to see through the cantilever. Must be magic.

They didn't drill a hole, looks like a diamond coating and not a real diamond cantilever as suggested by the branding. I think that Dynavector also has cartridges with the same cantilever type. I recognize the advantages of using diamonds for their optical and thermal qualities, a probe of some sorts or as a protective coating when needed but does anyone know why you'd want a diamond coated cantilever in this application?

david

 

[mem916]

Yes I also have the boron cantilever Coralstone. It is up for sale on Audiogon. I bought it in late June 2011. It still sounds wonderful but I have it priced to be reasonable even including the rebuild costs (~$2400 for Koetsu to rebuild it.)

I tried to post links to the recording I made from it but the moderator has yet to approve it. PM me if you would like to download them.

Nice !!! excellent shots...Careful with that cantilever. I own two Coralstones...probably my favorite cart...but I'm using boron for the cantilever. Do you have another stone body koetsu with a boron cantilever ?

 

[ddk]

I have never seen a diamond coating that allowed you to see through the cantilever. Must be magic.

Looks like one has magically appeared in your pictures, unless its just a reflection that looks like a metal cantilever inside it.



david

 

[mem916]

You are seeing something different from what I am seeing (obviously). I suspect you are seeing what you want to see. But regardless it makes no difference to me what you think you see.

Looks like one has magically appeared in your pictures.

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david

 

[ddk]

You are seeing something different from what I am seeing (obviously). I suspect you are seeing what you want to see. But regardless it makes no difference to me.

Obviously I don't have the cartridge here and I'm just looking at your picture, it looks like that there is something inside, if there isn't fine.

david

 

[rockitman]

Yes I also have the boron cantilever Coralstone. It is up for sale on Audiogon. I bought it in late June 2011. It still sounds wonderful but I have it priced to be reasonable even including the rebuild costs (~$2400 for Koetsu to rebuild it.)

I tried to post links to the recording I made from it but the moderator has yet to approve it. PM me if you would like to download them.

If you are able to articulate the differences you hear with the boron vs diamond cantilever...that would be great. One of my Coralstones is about 200 hours away for a rebuild, so I may consider getting diamond for it.

I take it you are not in the US ? Having done a complete rebuild by Koetsu this summer for my other Coralstone, the cost in the US was $4,500.00

 

[ack]

They didn't drill a hole, looks like a diamond coating and not a real diamond cantilever as suggested by the branding. I think that Dynavector also has cartridges with the same cantilever type. I recognize the advantages of using diamonds for their optical and thermal qualities, a probe of some sorts or as a protective coating when needed but does anyone know why you'd want a diamond coated cantilever in this application?

david

I suspect the diamond cantilever was manufactured around the stylus - hence, probably no drilling, as you say, but can't be sure. All I know is that the Chinese have some incredible manufacturing capabilities around synthetic industrial diamonds.