THE GOLD

MONGOOSE !

Expressimo Audio has done it again!

* The Gold Mongoose has proprietary amount of 24k gold plated giving the arm a magnificent sound! Each arm is sound tested for a true note pitch, this is the difference in the music. Pitch Perfect!

* It took Science and Geometry and out of the BOX THINKING to design the Mongoose Tonearm.

* Designed with Zero VTF when moving VTA / SRA

* Azimuth adjust at the rear of the arm wand. Specially designed tool for fine adjustment.

* 3 other Half Moon Heavy Weight sizes are Included. Designed for cartridge weights of  6 gm up to 16 gm.

* Ultra fine ,one touch tracking force adjustment.

* One Touch Cartridge Over Hang on the Fly Alignment. Go from Lofgren Baerwald to Stevenson on the FLY.

* Special proprietary bearings.

* The Gold Mongoose Tonearm is unmatched in stability. Has a 2" wide yoke from bearing to bearing.

* Wired with Expressimo Audio’s exclusive proprietary 99.99% Purity Silver wire.

* You also get a special designed Indicator arm wand. This allows you to indicate from Arm pod to the top of the platter. A level is for a carpenter not a precision setup. Expressimoaudio is a Master Tool Maker. Making custom tooling

* The Total movement of the arm pod VTA is .650
So if the arm is parallel in the middle of POD you can move up .325 and Down .325.
One degree on 12 inch arm is .212 Thousands

The Gold Mongoose Tonearm is uniquely designed like no other tonearm. The Gold Mongoose Tonearm has zero tracking force when moving the VTA. That is what gives Expressimo Audio the ability to design a Arm pod that moves VTA / SRA with Remote Control giving you, in real time on the fly movement.

How you ask? Science and Geometry. There is another force that’s rarely talked about and that is the vector force. This is the rotation of the platter, the down force of the cartridge and the placement of the pivot point. When you have the pivot point above the platter your tonearm gets pushed up. Tracking force is lost in the groove. With the Mongooses Geometry there is no loss of tracking force.

Neutral balance means no zeroing of the tonearm. Mongoose doesn’t have a "see-sawing" affect. The Mongoose Tonearm always tracks in the perfect place in the vinyl. Now you will hear the right spatial ques, the right placement , space , depth, and air between the instruments. A center that will blow you away.

The Effective Mass of  the Mongoose arm is designed for Med and Low Compliance cartridges.

To check Frequency Response use the HiFi Test Record.

Expressimo has the Tooling to get the Effective Length precise.
The tooling comes with the tonearm and arm pod.
Effective Length and the Over hang must be correct.

The main Effective Length is 11.950" × 25.4 = / 303.53mm

Mongoose Effective Length
303.53mm = 11.950 inches  
parameter                     Baerwald            
pivot to spindle (mm)    289.715               
effective length (mm)      303.53                   
overhang (mm)                13.815                   
offset angle °                   17.930                  
 

How to go from mm to inches  = .03937 ×
How to go from inches to mm = 25.4 ×
 

Stevenson - a variation on Löfgren geometry optimized for low distortion at the inner groove at the expense of increased distortion elsewhere. compared to Baerwald or Löfgren B you will get lower distortion for the last few mm of the record

Baerwald (identical to Löfgren A) - minimizes and equalizes distortion at the three weighted tracking error peaks resulting in moderate distortion between the inner and outer grooves

Löfgren B - minimizes distortion between the inner and outer grooves resulting in the lowest average RMS distortion at the expense of slightly higher distortion close to the inner and outer grooves

please use these two Calculators http://www.resfreq.com/resonancecalculator.html

Vinylengine

https://en.wikipedia.org/wiki/Piano_key_frequencies

http://americanmachinist.com/speedsfeeds-conversions-calculator

http://www.carbidedepot.com/formulas-turning.htm

Custom arc template generator for phono cartridge alignment (also prints nice strobe disks)