In the Format Conversion dialog you can invoke DSP studio. If you convert to PCM you need one to get rid of the quantization noise.Īs far as I know this setting is honored when transcoding on the fly or converting DSD to a PCM file. In Tools > Audio > Advanced > Configure input plug in, you can set the filter to be used. However, by upsampling we are presenting high bitrate music with the maximum signal to noise ratio and bandwidth- and that a good thing! Remember bit depth is just how low the noise is from the maximum level and sample rate is the bandwidth, neither one alone or together can tell you if a recording is good or not. Hence, the subjective responses to better sound. There is a part II to this, that Jriver or HQ Player may be more precise and use the computer's ability to do "slow math" (lots of calcs) much more than the DAC can muster. Most DACs go even higher bitrates internally.
Also, by doing the upconverting in the PC (Jriver) one can take advantage of the PC's ability to "lighten the load" of the DAC resource limited capacity. My understanding is that most DACs internally up convert from the native bitrate. A lot of people think this does the best PCM->DSD conversion, but it is not as flexible as JRiver.I do the same. And this is what I have been doing when it comes to playing music I carry in my DAPs.I am using JRiver to transcode on the fly, sounds pretty good! I want to try HQPlayer. With AKM, whether or not the DSD Direct feature is enabled depends on the DAC implementation.īack to the subject, DSD64 when compressed with WavPack creates very manageable file sizes as opposed to say FLAC compressed PCM 352.8 / 24 sources. With ESS you can never get rid of the HyperStream modulator for better or worse. Whether or not it will bypasses the internal delta sigma modulation of the DAC chip depends on the chip manufacturer and/or DAC designer. Without getting in to infamous PCM vs DSD war, I can say with DSD we at least get to bypass the internal digital interpolation filter that (most) PCM is subjected to in delta sigma DAC chips.
Offline DSD conversion makes total sense since it's a very taxing processing specially when working with higher order modulators. As Woland mentioned, if you totally rely on streaming services, keeping offline copies gets cumbersome. For 16x up-sampling, there is no option other than storing gigantic 705.6 / 786 kHz wave files.Ĭ. While FLAC and ALAC can handle sampling rates till 384 kHz, the file sizes are ridiculously big. Which means if we intend to defeat the internal digital reconstruction of the DAC chip, the sampling rate should be at least 352.8 / 384 kHz. Vast majority of DACs are Delta-Sigma chip based DACs which do 8x digital interpolation internally. An Rpi 4 will easily handle the load with more than enough room to spare in terms of CPU utilization.ī. PCM up-sampling even with long filters is still not as taxing as PCM-DSD modulation. I feel offline PCM conversion makes little sense.Ī. I am hoping making it open source will engage other devs to contribute to this project.Ĭlick to expand.My stance on offline vs real-time conversion is somewhat divided. There are several things to optimize - latency being the #1 issue (by decreasing the buffer size in the pipeline. Or do in 2 cascaded stages with different custom window techniques.
It can either do single stage 1M taps at 705600.
While I am not a fan of quoting taps as an indication of how good a reconstruction filter is quoting them here since gullible audiophiles will eventually ask. Presently, doing 16x up-sampling for only Redbook content (705.6K) on Rpi 4. But it sounds much better to me (actually my dissatisfaction with HQPlayer was the sole reason I embarked on this journey, but I digress ). It's by no means a finished polished product like HQPlayer. Post that, I intend to make my DietPi based Rpi 4 image open source which serves as a Spotify Connect client or as a DLNA renderer (Tidal/Qobuz via Bubble UPnP) and then up-samples using my custom coefficients. I am waiting on Henrik ( camilladsp author) to complete a feature enhancement which would eliminate the need of SoX in my DSP pipeline.