Trans Scend Survival

Trans: Latin prefix implying "across" or "Beyond", often used in gender nonconforming situations – Scend: Archaic word describing a strong "surge" or "wave", originating with 15th century english sailors – Survival: 15th century english compound word describing an existence only worth transcending.

Category: Headphones (page 1 of 2)

DIY MrSpeakers “Open Alpha” 3d Printed Headphones: Dan Did It Again!

Links:

Headfi forum with release and build notes

MrSpeakers headphone plug terminals 

Acoustic wool I used

Brainwaves earpads

Prices for Prusa i3 on Ebay

Other materials include a recycled Grado cable, spare bolts from my Prusa i3 printer (and obviously my i3 printer for printing, too) and Hatchbox black PLA.

I like the Hatchbox stuff, thus far it has proven to be affordable and reliable, even at low printing temperature (180 degrees is all I got).

One side, stock t50rp. Otherside, Open alpha.

Complete!

So:  Before I get into the build details, the bottom line is this is the definitive overhaul to complete in terms of t50rp mods.  I started with a refurbished mkiii,  and hated the crazy EQ spike at about where hihats generally reside.  This was not a subtle issue, and would give me a headache quickly.  From modding with the stock cups, I found denser damping=worse issue with treble and less bass.   Think of it like a bass trap- I used essentially felted wool, which in its raw form killed all frequencies except for the strongest... ...Which in this case was about 2.8khz to give a rough estimate.  Ouch!  After googling around, I discovered Dan was using cotton balls as the primary damping material, with a thin layer of dense acoustic mat of some kind to line the cup (helps mostly I think with leakage control and resonance from the actual plastic and flat surfaces on the cup itself).

Damping the Alphas:

I already had this fancy acoustic wool, so I figured I could make some "wool balls" by separating the dense wad into fluffy pillows.  I'd say I aired on the side of less dense- at this point I was printing my Alpha cups, and the space in there is huge, leaving ample space to layer up some of these wool balls.  I did not feel the need to line the cups with a damping mat of any kind, because my wool seemed to kill noise and reflection already like nobody's business.

Printing the cups and other parts:

...Painless, except on the inside of the cups there is a dip where the headband arm is mounted.   For no particular reason, I printed both cups without supports- but not without a large amount of "PLA spaghetti"  and the occasional emergency "duct tape the PLA spaghetti wad to the bed so it can have something to build on..."

Sound:

Firstly, these sound nothing like the stock t50rp.  AT ALL.  the low end goes quite low with not a huge amount of distortion, the mids are wide and spacious, and the treble (including the significantly tamed-down spike) is springing and provides nice "pop" and sparkle.  These headphones are a pleasure to listen to- I've been doing Art Blakey and Coltrain lately because the reproduction of the jazz bass is superb,  Couple that with the expansive space where the sax and piano reside, these make a nice way to relax at the end of a day (which is how I have been relaxing each evening since I made them).  Obviously, we still have some fundamental setbacks.  The Fostex driver is unbelievably inefficient.  It takes much care to juice these properly (I like them through my e12 portable amp actually,  because I can crank the input volume on that with very little distortion for quite a bit).   Additionally, there is a limit to how much detail we can siphon out of the driver; this uber mod definitely maxes out the clarity and definition this driver can provide.  For example, the successor to this headphone when it was made commercially by Dan/MrSpeakers is the AEON (still in preorder mode at the time of writing)- a completely in house design trickling technology down from the company's acclaimed ETHER headphones.  I am actually lucky enough to have had a few hours to play with them and chat with the inventor (Dan)- quite simply, the clarity and silkiness of the AEON demolishes the notion of clarity with my Open Alphas.  THAT SAID an $800 carbon fiber headphone invented from the ground up by Dan (who maintains the highest regards even from competitors (ZMF, even hifiman reps) as the most dedicated headphone creator) is obviously not really competing against a headphone a made for <$300 INCLUDING the 3d printer and donor headphones.... 🙂

 

Building Electrostatic “Earspeakers”

Below, you will find my collection of notes regarding how to build the electrostatic headphones themselves. This is largely based on stuff found at head-fi, in Wachara C.'s numerous posts and accomplishments on the subject.

DIY Electrostatic Amp Options

Embedded below is my current document highlighting the schematics, BOM, and cost of building a diy electrostatic amp.

The Audeasy Build

These are my notes on the current project, build a set of fabulous planar headphones from scratch.   This window into my Google doc will auto-update here as I add content.

Required Custom Tools?

"First, we build the fusion reactor.  then, upon creating the mini sun, we shine the light onto the prehistoric spores. We now evolve the subsequent grass to be healthy for the custom-wound sheep animal we designed.  Soon we will harvest the sheep to make the leather, which will of course be used for making the most comfortable ear pads in the... ...WHAT??!!  You wanted them in black velor and suede?!?!!"

Regardless:

In order to make the design and manufacturing processes faster and the most flexible a dorm environment (in addition to making the fabrication of bizarre custom objects that may or may not function possible), all outsourcing and use of specialized equipment must be cast aside.  Instead, we must build very, very small versions of rapid prototyping tools.  These tools are:

  • 3 axis CNC mill.  It only needs to be ~150mm cubed on the x,y,z axis, but it must have enough kick to not break or overheat when cutting hard wood cups.  This tool can be used to drill PCB (ES stators), make internal chassis pieces, and slice various materials to fabricate parts that can’t be 3d printed.  There is much to learn about how to use this tool, such that assembling one one is only the beginning.   
  • 3d printer.  This is my go-to for housings, internal spacers and interior connectors.   It is easy to use with some research, and a few hundred hours behind sketchup.  CADs include Sketchup and many additional extensions, Meshlab, 123d products, Blender, Inkscape, and more.  Often people will use multiple softwares to get the best results.  These printers can be built cheaply, requiring only an extruder, a small brain, and stepper motors (which can be avoided if extra work goes into recycling old parts from the floppy disk era).  The rest is up to the builder’s expertise in figuring out how to make the x,y,z axis function.  
  • Membrane stretching jig and etching tank.  These are about as cheap as an inner tube, a few buckets, and a battery…  ...However, care must be exercised in figuring out how to get repeatable stretch percentages and solid etches without destroying other materials in the chemical process.  
  • Transformer and voice coil winder.  This will be a very custom and relatively unusual tool, but will be helpful in getting the optimum step up voltages in amps.  Additionally, custom voice coils can be made for new dynamic driver designs.  The electrical parts are all very similar to those of a 3d printer or CNC- think a single axis moving back and forth to position wire very carefully over a spinning transformer or coil.
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