The SPL line was first introduced in 1999 and has since been logically developed into the more advanced SPL-R and SPL-Ultra lines. The common characteristics of this family are a closed acoustic design and the presence of a microphone for adjusting the frequency response of the device for a specific room.

The body of the Velodyne SPL-800 Ultra subwoofer is no longer rectangular; the side walls are slightly curved. This not only looks more aesthetically pleasing, but also reduces cabinet resonances. The walls are covered with piano varnish and sanded by hand. An enlarged centering washer and a wide rubber suspension allow for linear diffuser travel at large amplitudes. The 76mm diameter high temperature voice coil is wound in two layers on both sides of the base. All models in this series are equipped with a 1200 W Class D amplifier, as well as a cone control circuit that prevents too much deflection causing distortion in the sound. There is also a circuit for automatically switching to standby mode (after 8 minutes of no signal at the input) and switching back on based on the input signal.

The set of controls and switching elements is quite traditional: a crossover filter cutoff frequency control, a push-button volume control, an automatic mode switch, a linear/LFE input and output (output with low-pass filtering), high-level input terminals, an input for a remote infrared sensor ( not included) and a trigger input of arbitrary polarity. On the front panel, for ease of use, there is a power switch (in standby mode), a push-button volume control, a symbol indicator and a microphone jack. The indicator is multifunctional and, as a rule, serves to display the result of the current action (changes in volume level, phase, preset, mute and night modes). All settings, except the crossover frequency, are made from the remote control. The initial adjustment of the equalizer for a specific room is very simple: connect the microphone installed at the listening position and press and hold the EQ button on the remote control for a few seconds. After generating several variable tone (sweepton) sequences, the subwoofer will store the correction factors in memory and will be ready to operate with an optimized frequency response. In addition, as in earlier models, presets are available for four subwoofer operating modes: for movies, for rock music (any active music), for jazz (the most accurate bass transmission) and for games.

With a small volume of the body of the Velodyne SPL-800 Ultra subwoofer, the bass is quite average in depth, but nevertheless sufficient for a small room. The strong point of the device is versatility. Thanks to the extensive settings, you can choose any sound character for a specific recording. For example, in Rock mode, the lows are slightly compressed in depth, but are as dynamic and accurate as possible. The Jazz preset adds a little more roundness to the sound, while slightly loosening the tightness of the control in the lower part of the range. In the Movies mode, the membrane travel is maximum – this allows the subwoofer to competently operate with various sound effects. In game mode, priority is given to individual percussive sounds, while the impact and depth of the subwoofer are slightly reduced.