• Just click on the image below for a PDF of the project details •
Alternatively, you may prefer to build a mic using a PCB rather than stripboard...
Hobby microphone builder Mic Scharf has developed a PCB for this version of the project,
which you can obtain from:
HERE
The schematic above shows the audio circuitry required to create a Multi-Pattern condenser microphone, utilising a dual sided large diameter microphone capsule - 'LDC' - interfaced with a microphone pre-amp, fitted wih 48v phantom power.
The circuitry includes 2 x impedance converters - utilising a dual OPA1642 op-amp - and a summing/configuration amplifier using a single OPA1641 op-amp.
This simple interface uses the dual op-amp as 2 x unity gain non inverting buffer amplifiers, and a single op-amp to route the signals from those buffers appropriately to allow for the selection of Cardioid, Omni or Figure of 8 patterns
The op-amps have low quiescent current requirements - around 1.8mA each - low noise and very low distortion, and perform remarkably well for such simple circuit.
The stripboard layouts are designed to fit into that common 'donor body' - the BM800/NW700 - but also work well in Neumann 'style' clone bodies - from WGTCenter, for example... (Click on the image in the header at the top of the page to see more details)
• Just click on the image below for a PDF of the project details •
In this Multi Pattern configuration, a separate stripboard is required to generate the external capsule DC polarisation voltage. The schematic for that circuit is shown above.
As suggested, just click on either image to download a PDF which contains the schematics, circuit descriptions, and stripboard layouts for all the circuitry required.
Alternatively, you may prefer to build a VM using a PCB rather than stripboard...
Hobby microphone builder Mic Scharf has developed a PCB for this version of the project,
which you can obtain from:
HERE