Kali Audio HP-1 Multi-Reference Headphone

“Why is the curve so lumpy?” Great question. Headphones and loudspeakers measure very differently. Loudspeaker measurements make intuitive sense: a straight line more or less correlates to better performance. With headphones, the interaction between the headphones and the listener’s body complicates the measurement data. Simply put: a headphone that measures “flat” or “linear” will not sound very good, nor will the sound in the headphone translate well to other systems.

This has caused some vexation for headphone designers. If the goal is not linear response, what is the goal? Fortunately, a lot of research has been conducted in this field, and there is wide agreement[1]as to the general shape [2] the frequency response curve should take[3]. Although different sources provide additional nuance, the broad consensus is this:

• Headphones should have some boost in the LF, rolling off around the low mids (~200 Hz.)

• There should be another broad boost in the high mids, centered around ~3500 Hz.

• The high frequencies should roll off sharply from about 10kHz to 20 kHz

To put this another way, if your headphones measure flat, you will hear:

• Anemic bass

• Overly pronounced midrange

• Dull upper mids into the HF region

• A shrill, piercing upper octave

The goal of the HP-1, as with all of Kali’s products, is to present a neutral reference that you can trust for translation of your mixes. Critical reception of these headphones reinforces our point: these headphones sound great and are an excellent tool for anyone who is mixing.

To see the difference between studio mode and the other two tunings, use the drop-down menu in the above graph (where it says “raw measurement data”) and select “Normalized to Studio Mode.” This will show you where the other two tunings are boosting and cutting certain frequencies relative to the neutral sound of Kali’s studio mode tuning.

Quality Of Life

The HP-1 isn’t just a studio headphone. Because of the DSP chip processing the different tunings, the HP-1 also has quality of life features to make it a great headphone for casual listening and when you’re on the go!

Wired or Wireless Connection

Connect the included headphone cable for higher fidelity or use Bluetooth for on-the-go convenience. As your everyday headphone, getting used to the sound of the HP-1 will help you make better, more confident mixing decisions.

Active Noise Cancelling

When it’s loud out, engage ANC to block out the outside world.

Bluetooth Controls

Buttons on the headphone allow you to adjust level, go forward and back, and even pick up calls!

40+ Hour Battery Life

Get at least 40 hours of playback out of a single charge, then recharge with the included USB-C cable.

Premium Experience

With a comfortable vegan leather headband, replaceable vegan leather earcups, and an included carrying case, the HP-1 looks and feels as good as it sounds.