Stereo Location Sound

Audio-Technica BP4025 Stereo Mic

Audio-Technica BP4025 Stereo Mic

I’ve been recording sound effects and soundscapes for 25 years, and over this time have used a variety of kit. Previous stereo kit has included a Sennheiser MKH 30/40(60) M-S array and HHB Portadat as well as my ‘trusty until it broke’ Sony D50 and I often use my back pocket kit which is a Tascam DR-05 with a pair of low noise Primo EM172s.

My current go to combo for going out into the field to record soundscapes comprises a Sound Devices MixPre-3, Audio-Technica BP4025 X/Y Stereo Microphone and the dependable Rode Blimp II. The Sound Devices MixPre-3 features in a separate blog post so I will concentrate on the BP4025 here.

The BP (Broadcast & Production) 4025 is a singe point large diaphragm stereo mic with an innovative coincident capsule configuration. AT BP4025 stereo microphone capsules
Despite the angle of the capsules there is surprisingly no apparent energy drop in the centre front of the mic, and it produces an accurate wide stereo image with a really smooth detailed sound full of depth. For nature soundscapes, the low self noise of the BP4025 combined with the super quiet Kashmir preamps on the Sound Devices MixPre-3 can yield some excellent results. The compact size of the lightweight BP4025 also means it fits very neatly in the effective yet affordable Rode Blimp II, as well as being suitable for camera mounting.

Listen to some example nature recordings using the BP4025 in the video below


  1. Large-diaphragm capsules offer pristine sound quality and exceptionally low noise
  2. Phantom power operation—for use with professional equipment
  3. Switchable low-frequency roll-off and 10 dB pad
  1. Frequency response 20 – 17,000 Hz
  2. Dynamic range (typical) 131 dB, 1 kHz at Max SPL
  3. Signal to noise ratio – 80 dB, 1 kHz at 1 Pa
  4. Phantom power requirements 11-52V DC, 7 mA typical (both channels total)
  5. Weight – 269g
  6. Output connector – Integral 5-pin XLRM-type
  7. Frequency response:
    BP4025 frequency response
Alternative Stereo Mic Options

The AT8022 is very similar to the BP4025 and is a fair bit cheaper. It’s easy to use with either consumer or professional gear and is supplied with two cables for use with either pro equipment offering XLR inputs, or with consumer gear equipped with 3.5 mm TRS input. Can be self powered with a battery.
Frequency response is less on the 8022 at 20-15,000Hz, Dynamic range is less than the BP4025 at 109dB (compared to 130 on the BP4025) and the Signal to Noise ratio is -75dB compared to -80dB on the 4025.

Another popular alternative is the Rode NT4 but I have no experience of using this mic.

Interesting article comparing the Autio-Technica BP4025, the Shure VP88 and the Rode NT4