I wanted to build a server that is capable of running multichannel pipeline matrix processing (including convolution) and upsampling to the 8-channel exaSound e28 DAC at DSD256.
One challenge was finding a nice CPU for the task. When the new Broadwell-E generation of CPUs became available the choice became easier. Either 8-core i7 6900K with 3.2 GHz base frequency, or 10-core i7 6950X with 3.0 GHz base frequency. I ended up selecting the 6950X because then there's a core per channel
I built a new low acoustic noise machine for using HQPlayer on Windows 10 with exaSound e28 DAC (8 channel). This machine is currently based on Gigabyte GA-Z170X-UD5 TH main board for their Ultra Durable series. It has USB 3.1-C / Thunderbolt among all kinds other very recent features. CPU is Core i5-6600T (35W TDP) and RAM is 32 GB (4 DIMMS) of Kingston HyperX FURY Black DDR4 2133 MHz CL14 and passively cooled Seasonic Platinum 520 Fanless PSU.
Since the drivers for Intel GPU built
Now since there are MQA encoded FLAC test files available, I wanted to see how the file works out without MQA decoder - as a normal FLAC.
If we first look at the original 352.8/24 (DXD) file that has FLAC size of 69 MB:
We can see that there is content up to around 57 kHz.
If we then convert it to 44.1/24 we get a FLAC with size of 14 MB:
From the filter roll-off
There has been a lot of discussion about different types of volume controls. For comparison purposes of one case I chose to use Mytek Stereo192-DSD DAC which has three different volume control modes; analog, digital and bypass. Signal routing is implemented using relays. DAC chip is ESS Sabre ES9016S in stereo mode (4 DACs in parallel per channel). ESS Sabre has 32-bit volume control and internal DSP pipeline so it has 8 bits more resolution than allowed by 24-bit external input. It also has higher
Based on request here, I made some more square wave scope measurements using a high resolution scope for comparison with earlier measurements of DSC1.
Here are 7 kHz square wave results for the DSC1.
Here are 7 kHz square wave results for the iFi iDSD Micro.