[mmd8x28]

So I made my own headphones today. Literally, even the drivers are home made.

My drivers have a wax paper diagphram that is sanded down to be thin, but still tough, with magnet wire super clued in a perfect cylinder on it, around a neodymium magnet. Yes, a home made moving coil driver.

They are working great, VERY well actually. However the left driver was more bassy than the right. But after using them for a while, the right driver is starting to fill in on bass.

So I take it burn in also exists even when I make my own drivers? What is it, just the diagphram loosening up?

 

[jezz]

Short: yes; even home made drivers will "burn in."

Even wax paper has some degree of elasticity, as potentially do the other construction materials in your driver. They'll probably flex and move and will naturally be able to move freer and freer similar to how a well used piece of rope becomes more and more flexible.

 

[Sambones]

Haha, nice. I made my own drivers too. I wouldn't say mine were "working great", but it was a blast. I used packing tape for the diaphragm, and a canning-jar lid as the frame. I used 36 AWG wiring wrapped around a small tube and stuck to the tape. It had all the efficiency of an Abrams M1 tank, and a massive resonant spike at ~400hz, but I'm glad I went to all the effort.

I used a silicone (as in, caulk, not microchip) plate over a 14AWG wire frame as a plug for the back. This was to attempt to cut down on resonance in the frame, and to provide something to affix the magnet to.

Man, that brings back memories. The worst part was making the voice-coil. I used over 100' to get to an impedance of about 14 ohms, and I hand wrapped it. It was like 95 degrees Fahrenheit (about 27-30 Celsius?), and I'm pretty sure Satan was taking notes for future activities.

 

[mmd8x28]

Thats awesome. A lot bigger than mine.

I cheated on the voice coil, I put a pen in my drill, and had it rotate while feeding it magnet wire.. i got about 34 ohms on mine (my target impedance).. other driver got 32 ohms, so i don't know if that also is a reason for audible differences.

Mine hit bass and treble really well actually. I was going to get it tested today but they were closed.

 

[Sambones]

Mine might be bigger, but they sounded atrocious. how did you make yours? Like, what was the size, the frame, how did you suspend the wax paper, what size wire did you use, etc.

And the higher resistance with the same wire also means that there is more wire, so it has a denser flux field with a more powerful repulsion of the magnet. Hence more power and control, therefore better bass.

 

[nikongod]

I didnt realise you made the drivers in the other thread! Thats too cool!

I would burn them in. If nothing else it will verify their durability.

 

[mmd8x28]

Quote:

Originally Posted by Sambones /img/forum/go_quote.gif Mine might be bigger, but they sounded atrocious. how did you make yours? Like, what was the size, the frame, how did you suspend the wax paper, what size wire did you use, etc. And the higher resistance with the same wire also means that there is more wire, so it has a denser flux field with a more powerful repulsion of the magnet. Hence more power and control, therefore better bass.

The frame of them is sanded coat hangers (since they looked ugly originally), and are held tightly in place by hot glue (evenly coated).. The size is about an inch. The coil wasn't attached by hot glue though, that was attached by super glue. I put the super glue on the table top, touched the end of the coil on it, and placed it on the middle of the wax paper, so you don't even see the glue, it looks perfect.

My neodymium magnet of choice? The magnet from my shirt pin, lol.. I used 30 gauge magnet wire, if I remember. I'm not home right now. the cable itself I made for the headphones themselves was 24 gauge single strand.

 

[mmd8x28]

Here's the test I had performed today in the morning.

The chart was scaled to the minimum and maximum dB levels, and each frequency listed was it's testing point. The graph is smoothed to it.

 

[mmd8x28]

YouTube - Homemade Headphones

 

[dongringo]

Wow! That is just awesome. I think you ARE a mad scientist.

 

[Soaa-]

That's pretty cool. How'd you test the frequency response?

 

[mmd8x28]

One of my friends has some equipment he uses to test audio equipment including speakers, headphones, and even microphones..

There was ONE fault with my headphones we found. The right speaker, when sub bass frequencies get too loud, it chirps with clicking sounds. Couldn't find the problem but pushing at the base of the speaker changed the tone of the clicks. But it was only if the bass was louder than normal, and the volume control up too high.

Only the testing equipment or my Hifiman EF2 could even GET that loud on the bass, my iPod (with an oscilloscope app), couldn't even get that loud to produce the clicks. So obviously, if your crazy to be blasting it.

 

[Sambones]

Yeah, that was about my epxerience. Only, I didn't have the equipment handy to test them with, or to get a listenable volume. The best I did was testing by ear, running through a series of test tones. So, just judging by ear, the harmonics of the tones were fairly strong, and they were just about only good for the bass and lower midrange. They peaked at about 300-400 hz, kinda like yours, only it wasn't a fun peak.

About the video, I'm kinda disappointed that you didn't show the actual drivers. That's what I'm interested in.

I'm also curious about the volume at 2khz, which appears to be your zero point. The response appears similar to that of a Sony XB700 or a Sennheiser HD202, only without all the style

edit: er, I guess it'd be more likely that 500 would be the zero point...

 

[mmd8x28]

The drivers are encased, and hot glued, it'd be hard to show them itself, since I don't want to really mess with it while it's working good enough. They do get loud enough to put a ringing in your ears.

 

[Sambones]

I guess you have a point. But, yeah, in case I haven't thoroughly expressed how awesome that is, lemme do it again: that's awesome!