Rens Heijnis                                      custom-built audio equipment

B&K  DPANeumannSchoeps  AKGSennheiser



Improve the sound of your AKG microphone by retrofitting and separated power supply.

When you are not satisfied with the sound of your microphone: too sharp, strident, thin, lacking vibrancy
or anything else, it is possible to retrofit your microphone with better electronics to improve the sound.
Retrofitting is possible for nearly all AKG condenser microphones
such as 414, C460
After retrofitting your microphone has a smoother sound, less sharp and strident, more vibrancy.
At the former
microphones page you can read the theory about retrofitting:

A retrofitted microphone has a new printed circuit board with trough-hole components.
All the components are selected for there proven sound quality.


Mains power supply for active powered AKG microphones

No phantom power is used so an external power supply is necessary.

Technical Specifications PS-402
Number of channels: 2
Input: 4-pin XLR female connector
Output: 3-pin XLR male connector
Power requirements: 105-120V and 210-240V, 50 to 60 Hz
Power consumption max: 3W
Weight: 1 kg
Dimensions: 108mm 165mm 52mm (4.3 x 6.5 x 2.1)


The microphone Cable for active powered microphones

A special microphone cable is necessary between the microphone and power supply.
The standard microphone cable is a Mogami starquad cable:
Mogami 2534
For the +60V norm it is supplied with 4 pin XLR connectors.
Every cable length is available.
The output of the power supply is a normal 3 pin XLR.

For microphone cables with an other sound than the Mogami see: Microphone Cables


Retrofitted AKG 414 with active power +60V.



Retrofitted AKG C460B with active power +60V.


 Battery powered pre-amplifier for active powered  AKG microphones

Sonodore MPB-502


Battery power unit for  a standard AKG C24 tube microphone

Battery power for the AKG C24 tube microphone. Output voltage: 120V, weight: 5,3kg.
The original power supply will be used for the heater voltage and pattern control.


An example of modifications to a AKG microphone:

Modified AKG C12VR. Reference customer after modification:
The microphone has a fantastic warm sound now.
This is how a microphone should sound 
The S en the T words are controllable now and in balance with

the low frequencies. The sound is very addictive.


Price list retrofitting microphones