The Danville Signal Processing dspNexus 2x8 prototype in house for listening

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The Danville Signal Processing dspNexus 2x8 prototype is here and making music. Unit has two new AKM AK4493 and two new AK4499 DAC boards installed. The ADC is the great sounding AK5397.

Starting with the new headphone amp capability using Windows 7 and Audio Weaver for first testing. Using my HiFiMan HE500 headphones and sounding very good and no problem with plenty of headphone drive.

A new HAL MS-5 Music Server running Windows 10 is built and getting loaded with software to run the dspNexus 2x8 for the testing with the Monoliths and Magnetar speakers.

This unit has a powered mic input on front with separate ADC for measurements. 

The Raspberry Pi 4 2GB is installed and as software updates are made it will be running Raspbian Buster OS and measurement software like Room EQ Wizard.   The I2S bus is connected to the DSP and clocking will be from the DSP low noise clocks.   Will be testing with Linux based music players like Audacious and Audacity for recording.

This chassis is only for the prototype. Production units will have a new style of case similar to the one from the AXPONA2019 show.


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Rocket Ronny


The dspNexus 2x8 prototype system is now running The Monoliths speakers with the bottom half of the 6x12 servo sub arrays.

For this listening, the AKM AK4499 DAC's are driving the BOSC amps for both the BG NEO10 midrange and GR-NEO3 tweeter planars and the AK4493 DAC's are driving the Rythmik HX300 servo subs.

Getting the levels adjusted and so far very good sound quality!


Great to see it up and running. 

Any reason why 2 different DAC chips were used ? 

Will that cause any timing issues ?


This is a prototype to let us listen to both styles of DAC's.  Since they are modular, they can be changed at any time by opening the chassis and swapping DAC modules once purchased.

Once production is going, I will get more DAC modules for trials with systems needing more than 4 channels.  The DAC filter delays are not making any problems in The Monoliths speakers with the 3x12 servo subs for listening to this 3-way stereo setup. 

The baseline dspNexus 2x8 is to have the AK4493 DAC modules.  The upgrade system will have the AK4499 DAC modules.  Price increases from the baseline DAC's to the upgrade system DAC's.  The final prices are TBD at this time.


The production dspNexus 2x8 chassis front panel is now installed. 

The dspMusik 2x8 and dspMusik 2x16 in comparison to the dspNexus 2x8 system.


Long delay of an update due to the Covid19 trials and tribulations for 2020.

Since AKM had a silicon foundry fire recently, there is a now a long delay for new AKM DAC's and ADC's.  Danville has a supply of parts for units for a good period of time.  Also there will be other options for DAC's and ADC's being developed as the unit is fully modular for DSP's, ADC's and DAC's.   The unit now has AKM AK4493 and AK4499 DAC modules and AKM AK5397 ADC module.  All excellent sounding units with Class A output stage.

The recent trials are with the headphone amp function with different headphones.  Working with Audeze and will have a pair of LCD-MX4 phones for testing this week along with Sennheiser HD650 and HiFiMan HE500 phones. 

Next stage is bring up the RPi4 for room measurements, music playback over I2S Bus from files.  Then when Audio Weaver 8.x is integrated adding capability for room correction.  The DSP crossover function is already working well using the original Audio Weaver 5.16 implementation.

The user will now have direct access contiol to crossover functions, DAC and ADC filter selection, volume control, input selection system gain and other parameters via the IR remote control.

More updates as I get them and will pass them on.