Koss Nova Mod - Koss KPH30i Over Ear mod

I made this model to use some broken kph30i's I had. The kph30i original band likes to snap often as well as the swivel being fairly stiff causing discomfort over longer usage, it was natural for me to change that. 
Also, when I first started this mod, I had no idea what I was doing, and simply pressed buttons or commands till I got the result I wanted. Kind of still the case today. So one will likely see some quirks in the models. The whole kit is still sold on my website, but honestly, I don't want to bother making and selling it anymore at the price I have it listed.

This mod will require several things. 

• A pair of Koss KPH 30i

• PETG

• TPU

• M3 x 20mm self tapping screws, x14(more if the heads strip)

• M3 x 10mm bolts with M3 nuts, x4

• M3 x 18mm self tapping stainless steel screws with a wide pan head

• M3 x 12mm self tapping screws flat head(countersunk, chamfered style)

• M3 x 6mm self tapping screw x2 (If using the 3.5mm jack insert)

• 4:1 6mm heat shrink (I typically use heat shrink with adhesive)

• 1/16 rubber sheet, cut into 20mm circles as washers(not necessary, but stops some plastic noise)

• m50x sized velour pads, or steel series arctis 7 style mesh pads

• PJ-392A 3.5mm jacks x2, if using

All parts should be mirrored for the other side.

Print the band in 100% PETG. I usually use 3 walls and 45° infill directions. Support is needed fro the swivel point. 

Print the mesh cap, body, and pad mount with no top or bottom shell layers in whatever material desired at 40% or less infill. I usually use 30-40% honeycomb. Do the same with the TPU retainer, but in TPU and at a lower infill %.

Print the 3.5mm jack insert and Nova strap retainer however you like. Same with the TPU plug if using.

Print the TPU washer solid. It should be by default anyways.

Print the TPU spacer with 1 or 2 shell layers and low infill, say 5-10%. Support is needed for the underside.

The TPU Nova headstrap should also be printed without top and bottom shell layers, with a grid infill at 45° or whatever angle that has the infill lines angled at 45° to allow for stretching.

I'll make a picture guide eventually, but for now, deal with the text.

With the headband, cut a portion of heat shrink the length of the swivel joint(the + looking bit) and shrink it over that section. Leave the hole on front unsealed, cut away the excess if needed. That's where the screw goes.

Once the heat shrink has cooled, slide the Nova TPU spacer over said heatshrink portion until it snaps into the headband slot and is flush with the backside.

I'd attach the strap to the band now. Take some m3 nuts and drop them into the slots in the Nova strap retainer. Insert some M3x10mm bolts into the bottom of the Nova Tpu strap. It'll be finicky, but slide the Nova strap retainer onto the headband and insert the head strap bolts into it and screw them down until the m3 nuts seat themselves firmly. Try not to cross thread the nuts. Do this for both sides. Tighten down the bolts once everything is seated. It the strap is still too loose, use an extra m3 screw and slowly screw into the open hole on the strap retainer until it provides some resistance. Use the images to see how it's supposed to look.

Now, take each respective side of the mesh cap and place onto the headband heatshrunk hinge. Take a 18mm screw and insert into the tpu washer. If you have the rubber washer, insert the screw washer combo into the center of the rubber washer and screw until the rubber is fully punctured. Take the screw washer combo and insert into the hole on the headband joint. Screw down until the mesh cap moves with some resistance, but doesn't pop out the joint or doesn't move at all.

Take 7 of the 20mm screws and insert into the respective holes on top of the mesh cap on each side.

Line up the tpu retainer with the inner circle protrusion facing out and slide the screws into the respective holes. Make sure the large hole is the right direction/orientation.(the image with the black headphones have the retainers upside down due to a mistake)

Using the printed body, drop in your kph30i. The original band should be removed, like in one of the photos. I recommend having the stock pads removed, but the stock pads could be used for more bass. It should be a snug fit. If your cable is busted at the jack, now would be the time to strip the wire and rout it in the body.

Align the body and the screws on the other half attache to the band and screw it down. If the screw heads are hex style, be firm and slow to not strip the heads. The tpu retainer will act like a spring an push the kph30i housing down without introducing vibration noises.

If using the 3.5mm jack insert, line it up with the pattern on the bottom of the now complete enclosure. It'll be snug and will require some force. If not using the 3.5mm jack insert, simply slide the tpu plug onto the wire and insert into the enclosure. I typically don't use the jack or the plug.

Skip this if not using a 3.5mm jack. Solder the wires to the jack and press the jack into the jack insert. Screw a 6mm screw into the underside of the jack insert partially, until the jack no longer pops out.

Take the pad mount and line up with the 4 holes on the bottom of the body. Screw the 4 flat head/chamfer head screws. Mount your pads of choice and you're done.
The best pads were a thin velvet pad meant for the m50x. But they have been replaced with an inferior product, so the arctis mesh pads are the next best option to not color the stock sound.

For now, deal with my shoddy instructions, I'll flesh out a guide at some point....maybe. I think most of you will figure it out just by looking at the images.