Just took a photo of the DAC failure. It disappeared after turning off. No problems with my FiiO k7 after a year of use. Just a lot of pleasure from the sound

A lavalier microphone is not suitable for headphone measurements, but you can buy a Panasonic wm61 microphone capsule (less than $5), install it in a cheap lavalier with a 3.5 connector (be sure to remove the cover with holes and foam in front of the capsule), then build a stand for headphones...

It's better not to do this. This is an irreversible effect, removing the felt from the back of the drivers will significantly affect the sound (not for the better), and without good damping, distortion will increase

just solder the wires on the connectors this way

Please read this article, it contains details of how balanced connections differ from unbalanced ones, and there is also a description of the 4.4 connector https://www.headphonesty.com/2019/05/balanced-vs-unbalanced-audio-connections/

4-pole connector, because a balanced connection requires 2 contacts (positive and negative contact for each channel) and 3 contacts for an unbalanced connection, because 2 negative contacts are combined into one contact - a common ground

You need to look for a cable specifically for Fostex t60rp headphones, because different headphones may have different cable pinouts. I can advise you to cut off the 3.5 connector in your defective cable and solder a new one in accordance with the Fostex pinout (in the messages above I attached...

Fostex T50RP mk4 support balanced connection out of the box. For a balanced connection you need a balanced cable (pinout is the same as for T60RP). The headphones come standard with 1 unbalanced cable: φ3.5 mm (4-pole) ⇔ φ 3.5 mm (3-pole) stereo phone cable (2 m) x 1, φ3.5 mm → φ6.3 mm stereo...

updated model on the way!

Yes, you are right, I was wrong about this ess chip. I have an M15 and it does not support a microphone. As far as I know, the new M15i is practically no different from the M15

it doesn't have an ADC, so the M12/M15 doesn't support a microphone

Using a dimming film, I finally made the LEDs not so bright, so the M15 became pleasant to listen to at night before falling asleep. Previously, these were blinding lights in the dark

I decided to make a balanced 4.4 cable for my Fostex T60RP. I took the pinout from the manual that came with the headphones. I soldered the cable, and it converts the audio signal to mono - this is interesting. Where did I (or someone at Fostex) make a mistake? I downloaded the PDF manual from...

My modifications for the convenience of the Questyle M15. I bought a darkening clear film and covered the screen with it because the LEDs are too bright. I made a new cable because I can, because I wanted to check whether the cable makes a change in the sound (I didn’t find any effect) and I...

I checked some information and I think it's HR3020 polyurethane foam

does anybody knows the markings (density/hardness) of baffle foam?

a balanced output will typically have about a 2x more power, as + and - are amplified. you have the opposite in your answer, SE output is much more powerful than balanced

are you sure about that?

Is it safe to connect 2 headphones at the same time to k7 (bal and se outputs)? I did not find this in the instructions, but it was forbidden to do this in the FiiO ka3 instructions.

I have a guess that Airmotiv GR1 and Tripowin H1 have the same speakers. Here is a description and specs of the speaker for H1: 50mm Dynamic driver with 3-layer Polymer Diaphragm 105 dB Impedance: 32 Ohms The Tripowin H1 utilizes 50mm dynamic driver made with a custom 3-layer carbon polymer...

In your case, ferrite rings at the ends of the cable can help. They reduce high-frequency interference, that a long cable can accumulate. Adding ferrite rings helped me to remove the clicks on a cheap usb cable.

i have s12 and akg k371 bt. I have tried many different headphones and I think they are very close, if you can compare full size headphones and iem.

I recommend using soft glue so that the shell can close tightly and lock into place. superglue is not the best option. glue b7000 should be good (excess glue is easy to remove from the shell)

a little more about modifications. i decided to change pads. ordered from aliexpress angular HM5. but they are slightly smaller and the hole is much narrower. now a lifehack, how not to tear them, when putting them on and not get confused. you need a hair dryer and a spatula to remove the bike...

if you need a microUSB to typeC cable, this one works without any problems. it connects my microUSB phone to TypeC dongle (tested on FiiO KA3, Colorfly CDA M1 Questyle M15)