DIY microphone for Sony MZ R35 minidisc recorder.

As musician I often record rehearsals and concerts for my own use, and having used a Sony WM D6 cassette taperecorder for some years, I decided to try the MD player MZ-R35 from Sony.

One of the most usefull features for this work is the ability to record 74 minutes music whitout changing cassettes etc. Besides that I find the disc more usefull in terms of keeping track of the recordings.

In my work, I quite often wants to record lectures, meetings etc. and the MZ-R35 can record almost 150 minutes of monaural sound !

To do these recordings whitout much fuzz, I decided to make a small microphone almost built into the MZ-R35. I bought at small minijack, bent 90 deg., and soldered a tiny electret microphone to the jack. The microphone i salvaged from an old cell phone, and it appeared to have a very crisp and clear audio when recording.

The only drawback to this arrangement is, that it also records the sounds from the MZ-R35, but by only mounting the microphone in its leads, it is reduced considerably. For recording lectures and so on it is quite adequate.

To eliminate the sounds from the MZ-R35 as much as possible, I made another microphone mounted on a small piece of shielded cable. On the picture below you can see how I mounted the cable using two "jaws" to position the leads as precise as possible. In this way you can solder the leads applying as little heat as possible on the microphone capsule

Most microphone capsules has only two lead, one for ground, and one for both signal and supply voltage. You can identify the ground terminal from the small connections to the body of the capsule. The gound wire is soldered to the ground terminal of the jack, and the signal wire is connected to both the right and left terminal of the jack.

The microphone capsule was mounted with a few lenght of heat shrink, holding it tight to the cable.

When using heat shrink I normally use a heat blower for shrinking the plastic, but I experienced that this could damage the microphone capsule. Therefore I use my solder iron so that I do not put excessive heat to the microphone capsule.

When the MZ-R35 is lying on a table, the microphone points right into the air.

I have had many requests on how the terminals on a stereo plug is connected, and on the picture above you can see how it works. The left plug is the centerpin, and therefore the terminal in the middle when you look at the plug from the solder side (right side og the picture). When I made my mono version I just soldered the left and right terminal together. If you want to make a stereo version, you would have to use a shielded lead to two microphone capsules, and connect both ground/shield leads to the ground terminal shown above. The two signal leads should be connected to the apropriate left/right terminals.

I hope this will inspire other MD users in search of easy ways of recording.

If you are looking for further information on MD players, please visit the Minidisc Community Page.

If you have questions to my design, please contact me by E-mail or by ICQ# 101694656

Niels Linneberg