Moca wood anyone???

Psychicanimal · « **on:** 20 Jan 2007, 07:52 pm »

Hey, I re-entered this topic because I think many or most of you missed it the first time around.

Francisco, aka 'psychicanimal', sent me long ago a chunk of moca wood to use as an Isolator between cartridge and headshell. He uses the stuff all throughout his sytem as isolation aids and says they do wonders. Moca is a very interesting wood (paraphrasing PA's talk by phone a few weeks ago)....it is nearly 100% non-resonant. Could be good for you vinyl-heads.

Quote from: wikipedia

moca tree (Andira inermis), a beautiful flowering tree which grows to heights of 90 to 120 feet in the wild around Moca. The bark of the moca tree is poisonous. It was formerly employed as a vermifuge to expel worms (ascaris lumbrecoides) but used incautiously might cause death.

Allright, so nobody nibble on it, okay

I hacked off a couple of correct size chunks.....but my arm does not have VTA adjustment and any size hunk is too tall for my needs. I hacked off a couple for future use.

PA is offering anyone out there the large chunk of moca wood to hack off a piece and try it for yourselves. There is probably enough left for 75 or so cartridge headshell-sized pieces.

If no takers, he told me to send on to Dusty and CI Audio.........but I/he wanted to see if there were any others that wanted to try it beforehand. Wayner, gooberdude, ohenry....you're usually game for these kinda' vinyl related tweeks - what say you? Anybody else please chime in.

I'd have to ask PA (or you can via PM) if he wants it to go to Canada...it's his hunk, after all.

John / TCG (shipping from Bay area)

TheChairGuy · « **Reply #1 on:** 31 Jan 2007, 07:48 pm »

Just making sure all you tweekers see this post.....

woodsyi · « **Reply #2 on:** 31 Jan 2007, 08:13 pm »

I will try the moca isolator.

gooberdude · « **Reply #3 on:** 31 Jan 2007, 08:20 pm »

I'll give some moca a try too...

I could cut up a mapleshade maple block into isolators as well.

TheChairGuy · « **Reply #4 on:** 31 Jan 2007, 09:18 pm »

Allright then...we have in order now:

1. gooberdude - Chicago
1. woodsyi - Northern Virginia

I just need to ask Francisco/PA now to make sure his thoughts are still in this direction.....

John / TCG

woodsyi · « **Reply #5 on:** 31 Jan 2007, 09:27 pm »

John,

If you are shipping the chunk forward then I don't have any problem with gooberdude getting it first to save shipping cost.

gooberdude · « **Reply #6 on:** 31 Jan 2007, 09:33 pm »

Works for me too.

In terms of cutting this thing to size, will I need a band saw?

i have access to both a decent table saw & a fine band saw at work...

TheChairGuy · « **Reply #7 on:** 31 Jan 2007, 09:49 pm »

As long as okay with both of you, gooberdude is then up first.,

I used a fine blade hand saw myself.....the chunk is small; it doesn't take but 120 seconds to gnaw into and take apiece out.

gooberdude · « **Reply #8 on:** 31 Jan 2007, 09:57 pm »

Do you sand it down to be as flat as possible? and what thicknesses have you tried??

TheChairGuy · « **Reply #9 on:** 31 Jan 2007, 10:16 pm »

3/16" looks to be right. 5/16" was too thick I felt.

I haven't sanded it, as I haven't used it yet. No VTA (otherwise thrilled with TT, tho)

Maybe I'm more thrilled that I don't have to noodle around with VTA on this deck, too

gooberdude · « **Reply #10 on:** 31 Jan 2007, 10:28 pm »

TCG, what are you going to do if you need to adjust the VTA down the road? The sound changes quite a bit when i fiddle with the settings on my TT, it seems every few months raising the VTA by a smidge is a good thing...suspension sag.

One adjustment I never thought i'd use is Azimuth. It was set off-center from the factory since the cartr that came with the table's stylus was off a bit. The Grado Gold was the same way.

This new AT440MLa cartr stylus is dead-straight and adjusting the azimuth literally made the soundstage sound whole again...quite a trip.

having an adjustable table is great but learning how to work the adjustments is a pain.

TheChairGuy · « **Reply #11 on:** 31 Jan 2007, 10:53 pm »

I either shim the cartridge (a pain) or I have different size thickness rug underlay 'mats' I put under the Audioquest sorbogel mat to square up the difference in VTA. It's fairly small range of adjustment for different height cartridges....but cartridge aren't usually different by too much in height (those very tall Lyra's and Ortofons I don't have).

But, 3/16" changes things a lot...so I need small bodied cartridge to try it out on. I have an (small bodied) ADC XLM MarkIII I'd like to buy a new stylus for (old one is shot - but it with my table). But, I don't want to spend $75 for real ADC stylus (the aftermarket ones aren't recommended for ADC's as they are much cheaper shank).

Azimuth is huge with AT's line stylus. It is literally the difference between chucking the cartridge in the garbage....and listening happily. The AT440ML/OCC was that way, at least. It is still too tipped up for comfort...but without azimuth right it was horrendous souning.

Don't forget levelling your deck/platter with bubble level. It doesn't seem to matter with my JVC DD....but it was huge benefit on my belt drive, Thorens suspended deck of yore. HUGE.

Quote from: gooberdude on 31 Jan 2007, 10:28 pm

TCG, what are you going to do if you need to adjust the VTA down the road? The sound changes quite a bit when i fiddle with the settings on my TT, it seems every few months raising the VTA by a smidge is a good thing...suspension sag.

One adjustment I never thought i'd use is Azimuth. It was set off-center from the factory since the cartr that came with the table's stylus was off a bit. The Grado Gold was the same way.

This new AT440MLa cartr stylus is dead-straight and adjusting the azimuth literally made the soundstage sound whole again...quite a trip.

having an adjustable table is great but learning how to work the adjustments is a pain.

Wayner · « **Reply #12 on:** 31 Jan 2007, 11:07 pm »

If you don't have adjustable VTA and if you had access to CAD software and had a machinist friend, you could make the wood isolator wedge shaped. This would tip the cartridge in the tone arm, compensating for the change in VTA. If you add thickness between the cartridge and the mounting plate, you have in essence lowered the rear end at the pivot. To correct for this, you could put the wedge so that the cartridge tips towards the front. To illustrate this, hold your hand and arm out straight. now raise your arm and hand (still straight) at the elbow. now tip your hand back down at the wrist to return the hand to the normal to the surface condition. That means you cut a wedge shaped piece and point the tip of the wedge towards the pivot. This should put the rake angle back to 20 degrees. You will have to use a little trig to figure it out but one leg is 9.00" long and if the piece of isolator is an 1/8 of an inch thick, you can figure out what the angle offset is. By the way, it's .796 degrees or 3/4 of a degree.

Try it, you may like it. You may have the skill to make the wedge piece your self with a hand chisel.

W

TheChairGuy · « **Reply #13 on:** 1 Feb 2007, 03:10 am »

Wayner - thanks for taking all that time to explain and type out what I'd need to do.

But, I'm dis-eased enough at this point and juggling enough stuff in work and life....I don't think I'll ever get to doing all this just to get correct VTA. I do want to thank you for 'splainin' it all, tho

Throwing a different thickness rug underlay and spotting by eye seems to work fine. putting a 'tich' of Plast-i-Clay front or back would seem to achieve the same thing without resorting to CAD and machining. I've found VTA to be far less important than other set-up parameters so I'll continue my current course.

Thanks again, tho.

John / TCG

Psychicanimal · « **Reply #14 on:** 1 Feb 2007, 11:51 am »

Quote from: TheChairGuy on 31 Jan 2007, 10:16 pm

3/16" looks to be right. 5/16" was too thick I felt.

I haven't sanded it, as I haven't used it yet. No VTA (otherwise thrilled with TT, tho)

Maybe I'm more thrilled that I don't have to noodle around with VTA on this deck, too

1) You should install it just to get a feel for the expanded soundstage and gains in clarity.

2) Maybe Canada should be the last stop.

3) A bandsaw it's best cause of the thin kerf. Sanding to get it parallel & smooth should be good. The wood has large pores.

4) As for thickness, I don't know. Four blocks improve a component, a full 1/2" thick board is awesome, a 3/4" full board fantastic and after that adding more wood becomes a diminishing returns scenario. Since my 1200 has continuous VTA Í'm thinking of 3/8". My TT is still in the box.

5) I have an Asylum inmate from Belgium who made two Moca wood cartridge bodies for MC cartridges. We're awaiting results as soon as he buys a new Denon 103. His got busted during surgery. Perhaps I can e-mail the pictures to TCG and he can post them here.

6) Perhaps Gooberdude can cut many pieces and send them to the next guy. With a bandsaw and a guide all should come uniform & parallel.

***

woodsyi · « **Reply #15 on:** 1 Feb 2007, 01:43 pm »

Quote from: Psychicanimal on 1 Feb 2007, 11:51 am

6) Perhaps Gooberdude can cut many pieces and send them to the next guy. With a bandsaw and a guide all should come uniform & parallel.

***

I am all for this if you are up to it, gooberdude.

gooberdude · « **Reply #16 on:** 1 Feb 2007, 03:33 pm »

I'll gladly make some slices...no problem at all. Another AC member PM'd me about a chunk too. this'll be interesting to get feedback from folks with difft tt's doin the same tweak.

TCG, i've been asking around if the azimuth is crucial with the tiny diamond stylus on the 440MLa, up till now noone has commented one way or another.

I just eyeball'd the vertical, but it literally moved the soundstage to the right. granted, i could easily see the stylus was off to the left...but i was still amazed at the change.

this issue reminds me of summer camp as a kid in the Shawnee Nat'l Forrest, we'd have to march through a gigantic rock outcropping called 'fat man's misery'. It was a 30' tall gigantic rock that had a 6"- 8" wide crack all the way through it...every year a fat kid would get stuck so the leaders would crack open a 55 gall drum of grease and run it down the sides till it reached the stuck kid. In the meantime, kids are on top of the rock dropping candy into the abyss, while the greased up fat kid stands (stuck) with his mouth open 30' below hoping for a few gummy bears to drop in his mouth. This was an insane venture considering none of the camp leaders could get through the crack to help the stuck kid...

In order to traverse the crack properly, your hands, knees, elbows & back would have to grasp both sides of the rock - this is kinda where this story applies to azimuth adj.! If you let go with any appendage & lose traction, you'd slide fast as hell to the bottom a few stories below...skinning your knees and pissing off a bunch of spiders. Keeping proper grip and balance on the walls was key, and it was an enjoyable and memorable experience each time...scary as hell for the fat kid though!

it was 6 degrees here yesterday, i'm trying to think warm thoughts...

matt

TheChairGuy · « **Reply #17 on:** 1 Feb 2007, 04:43 pm »

Matt/gooberdude,

PM me your address please and I'll get the moca out shortly.

I've got 4 different sized chunks here for future use. Hand sawed, so they aren't ruler straight, but pretty good.

Thx, John

Psychicanimal · « **Reply #18 on:** 2 Feb 2007, 12:59 am »

Quote from: gooberdude on 1 Feb 2007, 03:33 pm

I'll gladly make some slices...no problem at all.

I've been a lot around woodworkers because I'm a professional tool sharpener. More than quite a few have incomplete or missing fingers. You get the point...be careful.

Listens2tubes · « **Reply #19 on:** 3 Feb 2007, 11:10 pm »

Guys can I get on this wagon?

I'd like to try some between the Karat D2 and my new Rega RB250, with Peter Riggle's VTAF it will be a snap to set up. Which brings up another point, Riggle will adapt his VTAF to most any tonearm. So why are you still reading this?

Oh yeh http://www.vtaf.com