A thought about the Longhorn mod.

drphoto · « **on:** 20 May 2010, 09:29 pm »

Ok, just got a Grado Green, and have read about the Longhorn mod. Now the original mod uses brass channel and solder w/ some plasticlay dampening, if I'm not mistaken.

Now if the whole idea is to increase the moment of inertia to increase stability, it seems all the mass should be located at the ends of the bar.

So why not use a carbon fiber rod w/ a chunk or blob of lead solder glued to the end w/ CA glue? Picture a tiny little barbell. Small diameter carbon rod and CA glues are available from the local hobby shop (at least one that has RC models, not just craft junk), where we supposed to get that brass channel.

TheChairGuy · « **Reply #1 on:** 20 May 2010, 10:03 pm »

We expect many photo's, drphoto, of your Longhorn creation

John

drphoto · « **Reply #2 on:** 20 May 2010, 10:31 pm »

Hey pix will be no problem, but does my idea make sense?

Carbon rod is very light, non magnetic and should be non resonant.

TheChairGuy · « **Reply #3 on:** 20 May 2010, 10:41 pm »

Quote from: drphoto on 20 May 2010, 10:31 pm

Hey pix will be no problem, but does my idea make sense?

Carbon rod is very light, non magnetic and should be non resonant.

Makes sense to me. Non magnetic and non-resonant being a bit more important probably than ultra-lightweight (unless your tonearm cannot support the std brass Longhorn addition)

Just use a blob of tacky clay to adhere at first instead of solder to make sure your idea works in reality.

I've used 3 pcs of 1.5" long copper magnet wire (12ga, I think) once. I lashed them together with superglue and used a glob of Quakehold (a product widely available in seismically active places like San Fran where I live

). That worked great, too.

Didn't look too purdy, tho

John

drphoto · « **Reply #4 on:** 21 May 2010, 02:24 am »

Ok, I got the cart installed and my take on the longhorn made, using CF rod. I couldn't find my bottle of CA glue, so I'm holding on the loops of solder w/ small bits of surgical tubing.

I'll shoot a pic sometime over the weekend. I'm holding the thing to the cart body w/ blu-tak.

Anyone have a guess at the proper total weight of the longhorn device? I could weigh this at work at the pharmacy tomorrow.

I ordered a VTF gauge and an antistatic brush and will wait until playing any vinyl until I get those things.

Now what's the deal w/ 'damping the coils' in the Grado? Something about silicone oil? Where do you get that and how do you apply it?

cheers,

joe

TheChairGuy · « **Reply #5 on:** 21 May 2010, 05:32 am »

Quote from: drphoto on 21 May 2010, 02:24 am

Now what's the deal w/ 'damping the coils' in the Grado? Something about silicone oil? Where do you get that and how do you apply it?

cheers,

joe

Dr. Joe,

You damp the coils with 1000cst silicone oil.

Cheapest place to buy it is at most hobby shops. It's called differential oil and used in the trannies of the little electric slot cars and remote control cars, boats, helicopters, etc.

A couple ounces is usually $5 max.

That part of the mod is very sublime. But, it focuses the sound of the Grado a little better with overdamping (which Joe Grado zealously avoided)

John

Wayner · « **Reply #6 on:** 21 May 2010, 08:44 pm »

The Longhorn Grado needs to be a unified assembly, free of even the minutest vibrations for it to work properly. The outboard down-riggers floating in air to help the tight rope walker balance the single thread, the stiff, yet non-resonant channel, to channel away unwanted energy with plasticlay to help things along. 1000 centi-stroke liquid silicone to calm the nerves and cantilever pivot. Then to finally track your favorite tune (at 1.6+ grams) with VTA just right and anti-skate to make it float on a blank disc as if in free air.

440 ohms resistance in each set of coils will ensure the circuit is complete.

Wayner

drphoto · « **Reply #7 on:** 22 May 2010, 03:40 am »

So, Wayne, you would say the tried and true brass channel w/ plasticlay is the way to go?

I'm not trying to reinvent the wheel, I just had some CF rod on hand from days of flying RC helicopters. (none of which used a transmission, so no silicone oil....mine were all electric)

So do you put a drop of oil into the spot where the stylus cantilever goes into the cart body?

I reviewed the Audio Basic archives (which is where I saw the longhorn plan) but couldn't find this part.

thanks guys. fun to get back to vinyl. I hope I can do it on the cheap. Though, new records cost a fortune!! damn!

sure is one way to end piracy though. Ya can't download vinyl.