Should You Connect the FetHead to your Mic or Interface?

In a recent discord discussion the question arose on whether you should connect your fethead or mic activator directly into your microphone, or if you should connect it directly to your interface. I tried a few different mic activators/preamps: The Triton Audio Fethead, sE Electronics Dynamite DM-1 and the Cloudlifter CL-1.

TESTING PARAMETERS

For this test I used a 150-Ohm dummy XLR plug, and a 15-foot Mogami XLR cable. Halfway in between the microphone and the interface, I turned on and off a handheld vacuum to introduce interference. Here are the audio samples which are boosted around 50dB to make the noise more apparent.

TRITON AUDIO FETHEAD

SE ELECTRONICS DM-1

CLOUDLIFTER CL-1

FINDINGS

With all 3 mic activators / inline preamps, I found that the interference was less noticeable with the inline preamp close to the mic while the interference become more apparent when the mic activator was near the audio interface after the 15-foot cable run.

MY THEORY

The reason I think this is the case is when the mic activator is added after the long cable run, it is not only boosting the microphones signal by ~+25dB, but it’s also boosting any interference and noise picked up in the cable by ~+25dB. With the mic activator near the mic it is boosting your audio signal by +25dB making the microphones signal significantly louder than any interference that might be introduced over the long cable run.

CONCLUSION

Based on my findings, I believe it would be beneficial to put the mic activator closer to your microphone prior to the long cable run to avoid amplifying any kind of interference picked up by your cable. However, the noise so incredibly low that it really is negligible, so if you are unable to follow this advice I really don’t think that it would be very detrimental to your recording to have the mic activator in line after a long cable run.

With that being said, this is not a scientific study, and it has a sample size of 3. If you would like to contribute to the data, please leave a comment letting me know what you find with your mic activator / inline preamp.