ESX QL812SP - 12-channel DSP processor

QL812SP

With the QL810SP and QL812SP processors, ESX demonstrates what true high-end DSPs are capable of. Even the components are top-of-the-line: not only are high-quality 32-bit converters from AKM's 5 series used, but two of the ADAU1452 processors, the best from Analog Devices, are also employed. This is where the wheat is separated from the chaff: conventional DSPs usually only have one DSP core. However, if a DSP has many channels and the corresponding equipment, computing power becomes scarce. This is not the case with the new ESX top models – on the contrary. The two QL DSPs have so much reserve power that they can easily process not only 12 channels, but the developers have also implemented numerous functions as well as the revolutionary ESX Expert Staging Equalizer with balance and level functions, which allows for further refinements in fine tuning.

The entire audio computing power is also controlled in the ESX DSPs in a manner befitting their status. Command processing is handled by a powerful ARM Cortex® M4 high-performance CPU with 240 MHz and internal 1024 kB flash memory. This is the only way to work in real time with maximum performance. With the new QL812SP, ESX is now cementing its high standards in the field of high-end DSPs: in the test review in the trade magazine Car & Hifi 3/2022, the QL812SP impressed so much that the test editors not only rated it as a highlight, but also considered it the best DSP "under 2000 euros." This is remarkable considering that it is available for just €1,000.

Bluetooth on board 

Bluetooth is standard on the large QL DSPs. With this connection, you can either stream music wirelessly or—and this is really ingenious—control the entire DSP with a tablet or smartphone using the "ESX TOOLKIT" app developed specifically for the new processors. This completely eliminates the hassle of connecting a PC.

• Analog Devices™ ADAU1452 dual 2 x 32-bit processor, 294 MHz, Full HD audio 96 kHz
• AKM Velvet Sound™ Series 5 signal converter, A/D 32-bit, D/A 32-bit
• HP/LP/BP @ 6-48 dB, phase shift, delay correction 0 ~ 20 ms / 0.01 ms steps
• Input mixer, subwoofer control
• Input sensitivity: Low level 1~6 V/RMS, High level 1~15 or 15~45 V/RMS
• Signal-to-noise ratio (A-weighted): Analog input 111 dB, Digital input 117 dB
• Total harmonic distortion: Analog input <0.001%, digital input <0.0004%
• Integrated Bluetooth® receiver incl. antenna for controlling the DSP via app and Full HD audio streaming Bluetooth version 5.0, profiles: A2DP/AVRCP, codecs: aptX, aptx LL, aptX HD, AAC, SBC
• Optional RC-DQ (LCD remote control)

Technical data

• 8 x RCA/cinch input
• 8 x high-level inputs with EPS PRO up to 40 V/RMS (via Molex connector)
• 1 x optical stereo, S/PDIF 192 kHz, 24 bit
• 1 x coaxial stereo, S/PDIF 192 kHz, 24 bit
• 1 x Bluetooth® stereo
• 1 x USB Type B for PC software
• 1 x RJ45 for remote control/extension
• 1 x power input incl. REM OUT and MODE switch input
• 12 x RCA/cinch @ 6 V RMS (THD+N <0.0004%) with 31-band EQ, PEQ / high shelf / 
• 226 x 43 x 120 mm