It's absolutely beautiful. Your woodworking skill is to be admired and envied. How much does it weigh?

Gorgeous!

Wood like this is amazing - it is musical.

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How much does it weigh?

It weighs in at 243g which is about 8.5 oz, iow just over half a pound. It feels unexpectedly heavy in the hand; Mpingo is dense hard stuff!

Thank you Struts - it must be fun just to hold it. Or toss it to an unsuspecting friend while shouting "heads up!"

Again, beautiful work, Doug.

I know I have said this before, but your work is mui fantastico.

No kidding around or anything here...your work is just straight great.

Have you ever looked at Edgarhorns or anything like that?

I think no matter what you make, it will pretty much be first rate.

When knocking off Shun Mook Mpingo devices such as the humble Mpingo disc, the Spatializer Kit (3 discs) and the Record Clamp it's worth considering that each Shun Mook disc (and the knock-off) is directional - in both vertical direction and horizontal plane. The actual Shun Mook disc is marked on the edge as well as on one side, allowing the user to place the disc on a surface correctly and rotate the disc for best results. A single Shun Mook disc can be quite powerful in the correct location in the room, so can a knock-off, however location and directionality are critical. In order to get there, each homemade disc must be marked for direction by ear. The directionality problem is compounded greatly when multiple discs are involved - such as with the Spatializer Kit and the Record Clamp. It's pretty easy to see that without proper marking of the discs, one by one, you can easily wind up with nothing or worse than nothing.

~ Cheers

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W...that each Shun Mook disc (and the knock-off) is directional - in both vertical direction and horizontal plane. The actual Shun Mook disc is marked on the edge as well as on one side, allowing the user to place the disc on a surface correctly and rotate the disc for best results.

I have never seen one in person, but are they not symmetrical? If so, how could they possibly be directional?

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W...that each Shun Mook disc (and the knock-off) is directional - in both vertical direction and horizontal plane. The actual Shun Mook disc is marked on the edge as well as on one side, allowing the user to place the disc on a surface correctly and rotate the disc for best results.

I have never seen one in person, but are they not symmetrical? If so, how could they possibly be directional?

Maybe they are directional like wire?

I forgot about grain, although in my experience the denser the grain structure the less directionality the wood has. Ebonies are very dense and close grained.

Interesting comparison information, fun to read!

The Mpingo disc is a resonator, quite a powerful one. Doesn't the word "Mpingo" mean "talking wood?" - something like that, it has been a while. Anyway, the trick is finding the magic location where it kicks in. If the record clamp isn't built from the ground up, and each disc carefully "measured" and marked prior to assembly, then the structure of the finished clamp as a whole will be out of whack, relatively speaking, regardless of whether the clamp is spinning or not.

Cheers

We frequently visit a place that is near some ancient bristlcone pines. If there is ever any deadwood, I'll try and get you some 2,000 year old wood to check out.

Probably too late for this season, 'cause the snow will be there soon, but maybe next spring!

Most likely you misinterpreted my comments. I am simply saying the Mpingo discs (and knock-offs) operate via mechanical resonance. I am not suggesting there's anything magical going on, tho as I said the effects can be magical, it all depends. IIRC the "ebony" commonly used in musical instruments is actually a type of rosewood, not Mpingo wood. One more thing, the original Shun Mook Mpingo disc has a rather odd feature - there is a small circular cut-out in the disc that I understand contains a small quartz crystal.

Cheers

Mpingo is used to make clarinets and oboes. Rosewood is also used - which makes sense as these words are of the same genus.

It is musical in the sense that it rings or resonates with mechanical energy. A piece of it struck gives off a pleasant sound.

I used it and rosewood making harpsichords, hammered dulcimers and other string instruments for nuts and bridges as these woods transmit the energy from a plucked or struck string energy very effectively to the soundboard.

The direction of the grain does not matter for this purpose. Thus the question re directionality. If it's round, it's round. And uniform throughout.

I suspect our resident woodworking expert agrees with me that the direction of the grain makes no difference when working the wood. The stuff is simply very hard in all directions.

The 2,000 year old wood would be fascinating, just so it isn't petrified. Wood salvaged from centuries old underwater wrecks of ships that were transporting wood would also be fascinating to work.

The comparison between Delrin and Mpingo record clamps still intrigues me. Why would the material make a difference? Delrin is a bit lighter, but has uniform density as well.

Very good points and thinking. Maybe some time we will know how these physical differences influence acoustics.

Speaking of rosewood and resonators, anyone care to take a stab at knocking these little bullies off? No, you don't have to explain how they work.

http://sixmoons.com/audioreviews/acousticsystem4/sugar.html

~ Cheers

No one can "explain" how they work other than a psychologist.

These two (Marja & Henk) are consistently, delightfully nuts.

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And also not being somehting pets or children will attempt to ingest or carry off.

I think one has to be very careful making anything for a TT out a material that rings. Perhaps this is why such woods are not used for platters and plinths.

The cost on that clamp is mind-boggling!

Piano tuning: My experience is that every piano has its swet spot, the condition to which it always returns and stabilizes. For example, I have seen pianos that go out of tune when in the sun, but return to perfect intonation when the sun moves away (don't ever keep your piano where this occurs - not good for it). The same is true of humidity, although the cross layering of soundboards and pin blocks makes this less of a factor.

My expectation was that such changes would quickly drive the instrument out of tune, but they are actually quite resilient. Of course, this kind of environmental exposure eventually drives them out of tune - but so does playing.

http://www.6moons.com/audioreviews/shakti/hallograph.html

Yet more exotic hardwood resonators to the rescue.

"A recording that seems too dry is instantly livened up with a slight rotation more toward the listener." .....hmmmm

Cheers

I've wanted to play with these for a long time.

It they weren't so expensive I'd buy them just as a decoration; they are strikingly odd.

They pop up from time to time on Audiogon; there's a pair there right now for half price, but sale pending.

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I've wanted to play with these for a long time.

It they weren't so expensive I'd buy them just as a decoration; they are strikingly odd.

We played with those one year at T.H.E. in Alex Paychev's APL Hi Fi room.

People sitting in the sweet spot could listen blind and be able to tell when the things were raised and lowered.

Off axis, the effect was not dependably demonstrated.

We've done the same thing with those stand things with the three PVC pipes standing vertically. Those made the imaging "larger," but less 'specific.'

I guess my take on these is similar to the first three rules of real estate: Location, location, location.

Hope that isn't too controversial.

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People sitting in the sweet spot could listen blind and be able to tell when the things were raised and lowered.

Really? They don't look large enough to do much of anything.

Did the improve or impoverish the sound?

"I guess my take on these is similar to the first three rules of real estate: Location, location, location."

Location is important since the culprits are reflected acoustic waves and standing waves in the room that are room'system dependent; however, the experiments you conducted in Alex's room also illustrate the illusive behavior of the exotic wood itself:

Direction, direction, direction.

Hope this is not too controversial.

"They don't look large enough to do much of anything."

That sounds like a topic for a new thread. (Only joking).

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...Of course, many of us won't have to worry about that because the Voice of Reason, i.e. our female partners, would never allow it to happen.

Yes, the warmware problem.

I occasionally experience a carbon-based speed limiter when driving. It's the G force accelerometer that needs to be reset; 130 mph in a straight line is no problem, but the same speed in a sweeper results in squealing. I don't get it.

Back to audio: the holographs look pretty complex for Doug to easily replicate.

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People sitting in the sweet spot could listen blind and be able to tell when the things were raised and lowered.

Really? They don't look large enough to do much of anything.

Did the improve or impoverish the sound?

Ah, the question.

Well...

I think that audiophiles are profoundly predisposed to confuse 'different' with 'better' when they hear a difference in something...at least at first listen.

It's a mixture or self congratulation for having identified a difference, the initial rush of something being different, and having their listening apparatus tickled by a different sonic signature that may, initially, seem to be delivering new (deeper) insight into what they are listening to.

So, I can't really fall back on whether they made the system sound better, if that makes sense. Better/worse is the part of this discussion that I think takes me the most time and effort to figure out, and it is not the realm of instantaneous DBT/SBT's to determine in this type of condition.

I apologize if that was an obtuse answer.

For my own experience with them...

They were placed at tweeter height, and initially altered that tweeter driven sensation you sometimes get of a feeling of more ear pressure when there is a sudden shift in your sonic environment.

What I think they were doing was acting as a new reflective surface, and I may have been getting more HF signal arriving at my ear sooner than if the sound had travelled off to some other surface, instead.

Even though you could "feel" (in sense terms) more than "hear" them go into place, my initial impression was 'different' rather than a feeling of 'better' or 'worse.'

The testing was pretty darn close to ideal instantaneous SBT conditions as I can think of, though.

AS I sat longer, I thought maybe they added a bit of HF emphasis and changed the imaging, but I would need more time to really come to a 'better' or 'worse' description.

I have my doubts as to someone being able to align and callibrate each piece of wood to accomplish grain-directional characteristics that would be the cause of the effect rather than the result of the more macroscopic effects of reflection, etc.

It could easily be tested, though. Just make them out of different materials. As to Doug making them, we could look around at wood catalogues and see if the wavy parts are pre-made.

Cheers.

Addendum:

Trying to explain the feeling still...

Have you ever been listening and then started a new track or had someone put on a new tune and, initially, the sound was set too high? For me, that will sometimes alter how my ears feel, and that sudden burst of extra HF will kind of persist for a second or longer, even as the vloume is decreased. When those devices were moved in and out, I could feel that feeling, only to a much smaller degree.

Great description, Buddha. Astonishingly good in fact - one of the best. Conveying aural experiences with words is incredibly difficult. You made it look easy.

And Doug, I laughed at "wacky wave stands".

Ebony ain't that expensive, it's the Mpingo that's super expensive.

Cheerio