Welcome to our "In-Depth" blog series, where we take an insightful dive into the intricacies of our IEMs. In this article, we go in-depth into our SLAM technology — the reason why our woofers leave a lasting impact.
The quest to reproduce dynamic swings
In the search for an IEM woofer technology that can accurately capture the dynamic swings that speakers tend to reproduce well, we experimented with different driver types, new acoustic chambers and different driver materials. SLAM technology was a result of this rigorous development and was the only solution that produced the bass presentation we desired.
What does SLAM entail?
SLAM technology is our proprietary method of decoupling drivers. To understand how the SLAM topology works, we first modify and build upon a dual driver unit. A dual driver unit typically features 2 combined woofers that share a single output spout:
A dual driver unit sharing a single spout. Source: Knowles.
Dual driver units are often utilised in IEMs to increase bass output as 2 woofers can reproduce more SPL/loudness. However, the drivers within the unit share the same crossover and are hence playing the exact same frequency range. We discovered that this conventional method of tuning was insufficient to accurately reproduce the bass impact needed.
To modify the unit to become Subtonic SLAM woofers, we use both acoustic and electrical crossover means.
Modifying the dual driver unit
Electrically, both of the drivers do not share a single crossover, but instead we tune them both separately, assigning a separate crossover to each of the drivers dedicating one driver to sub-bass and one to mid-bass. Acoustically, the dedicated subwoofer is vented for additional decay, extension and rumble, while the mid-bass woofer features an internal chamber for tighter control, more snap and greater impact. Splitting the dual unit in this way also ensure that acoustic phase coherence is maintained.
Collectively, this provides us with finer control when sculpting the frequency response, and also allows us to fine tune the decay characteristics of the bass, utilising the different crossovers and chambering systems on each driver. This solution allowed us to achieve the natural and tactile bass presentation we were striving for, akin to subwoofers in a treated room.
The combined effort - acoustically and electrically - results in SLAM woofers achieving a whole new level of tactility and impact while retaining precision and control, compared to conventional woofers. With true extension down to 3Hz, the bass from SLAM woofers is not only heard - but felt. Every dynamic swing is accurately rendered, redefining what is possible with IEM woofers.
Although the SLAM modification takes a longer time to implement, the results are well worth it.