KZ-Castor

Tuning Adjustable Dual-Driver IEM

Challenging all flagship products in the HIFI industry with its formidable strength Harman Target Version

Built upon the acclaimed Harman FR curve within the HIFI community, and pushing beyond its boundaries!


In the past two years, many audiophileshave been pursuing a higher degree of adherence to the Harman FR curve. Many brands have used the Harman curve as a reference to launch their flagship products. Due to the challenging nature of acoustic tuning involved in achieving the Harman curve many brands only fine-tune their flagship products to a relatively high degree of adherence. On the other hand, some lower-priced products, constrained by technology and cost, do not follow the Harman curve style in their tuning.


KZ-Castor breaks through traditional acoustic tuning methods by innovatively adopting a dual-dynamic driver acoustic design. This approach has resulted in the perfect Harman curve that outperforms flagship products from other brands.

 Parameters and performance comparable to other flagship products from other brands, but at only a fraction of their price. Innovative Stacked Dual-Dynamic DriversStructure Design


Castor features a unique design with two stacked dynamic drivers. One driveris dedicated to producing frequencies around 20-200Hz for bass output, while the other diverhandles mid and high frequencies. Through precise electronic crossover technology, these two divers work synergistically without interference between their frequencies. This enables Castor to deliver powerful and energetic bass as well as stunning mid and high frequencies. Customized for Audiophiles Seeking Deeper Bass

Harman Target with Improved Bass Version

Traditional earphoneproductsoften exhibit a drop of around 6-7dB in the frequency range of 40-300Hz, and some earphoneproductsmarketed as HIFI may even have a drop as low as 4-5dB. (Why do so-called HIFI earphoneproductshave less drop in the low frequencies? This is done to create a false sense of perception for users. By reducing the low frequencies they aim to make the mid and high frequencies seem better, claiming it's for low distortion. In reality, this is all deception, as they can't technically enhance only the 100Hz frequency range without affecting other ranges.) This meager drop in low frequencies is like reducing the explosion of a nuclear bomb to the sound of a firecracker.


In contrast, Castor boasts a drop of over 10dB in the 40Hz-300Hz range. If we use the acoustic theory that 6dB represents a doubling, Castor's performance in the low-frequency range has decisively outperformed traditional headphones both in data. Experience unprecedented and breathtaking super bass

When we set the bass frequency range to 20-200Hz, traditional manufacturers often attempt to adjust the sensitivity of this range by altering the unit's damping. The primary limitation here is that it's nearly impossible to boost only the 20-200Hz range without affecting the 300Hz range; excessive boosting in the 300Hz range leads to muddiness in the sound. However, with our Castor's dual-driver design, one driver is dedicated to independently handling the 20-200Hz frequency range and fully amplifying the output within this range. This approach allows us to achieve an unparalleled and stunning bass experience. Built-in professional-grade filters, supports adjustable low and high frequencies.


Castor is equipped with professional acoustic filters that support 2-stage adjustments for low frequencies and 2-stage adjustments for high frequencies. Users can fine-tune their sound preferences to create 16 different audio profiles based on their preferred music styles Top and bottom stacked cavity structure

To strike a balance between sound quality and comfortable wearing, Castor adopts a top and bottom stacked cavity design, resulting in a smaller overall earphone size and improved comfort during wear. A higher precision integrated injection molding process than 3D printing.


The precision of the integrated injection molding process is theoretically more than 10 times higher than traditional 3D printing technology. The tolerance range of traditional 3D printing is around 0.1mm, while the precision of Castor's internal support structure is around 0.01mm.