restorer-john
Grand Contributor
My guess would be you have a hard time finding recordings that have non-noise info above 14 bits.
? All CDs bouncing on 0dBFS have 16 bit non noise related content or did I misread the context?
My guess would be you have a hard time finding recordings that have non-noise info above 14 bits.
Not the way I see it. If anything they might only need 4 bits. Assuming the musicscope works reliably to report this random noise from microphones and every other analog step in the chain I think will increase noise above the 16th bit nearly all the time. 96 db dynamic range would have a signal, which isn't noise down in those lower bits.? All CDs bouncing on 0dBFS have 16 bit non noise related content or did I misread the context?
My view on this unit overall is thst the DAC section is pretty average, the ADC is not great and the internal resampling, if using digital input, is definitely something to be avoided.
However, in the context of price and functionalty it still is good value for money. I still think it would probably beat a passive crossover.
So come on miniDSP, time to build a truly high performance unit
Is the video capture capability built into the Musicscope or if not what are you using for that?
If you are using the analogue input its not an issue, but if using usb or optical get your media playing software to updample to 96kHz prior to sending it to the miniDSP. J River and Roon can do this.Seems like a reasonable assessment. Now how does one avoid the internal resampling?
Not the way I see it. If anything they might only need 4 bits. Assuming the musicscope works reliably to report this random noise from microphones and every other analog step in the chain I think will increase noise above the 16th bit nearly all the time. 96 db dynamic range would have a signal, which isn't noise down in those lower bits.
Not the way I see it. If anything they might only need 4 bits. Assuming the musicscope works reliably to report this random noise from microphones and every other analog step in the chain I think will increase noise above the 16th bit nearly all the time. 96 db dynamic range would have a signal, which isn't noise down in those lower bits.
Using JRiver to perform the SRC to 96kHz prior to input into the miniDSP. I think the lesson here is perform the SRC to 96kHz first to avoid the miniDSPs somewhat sub optimal conversion!
View attachment 11767
I have a 2x4hd firmware upgraded to DDRC-24, meaning that my unit upsamples to 48khz, right? Even so, should I feed it 96khz files? Isnt 48khz enough?
48 kHz is enough. No benefit from anything higher.
Thank you. Do you think that the 44.1khz->48khz upsampling with normal files would be audible?
No. Upsampling has to be pretty badly implemented to be audible - just ask any record label, that is how most of the "hi res" recordings are produced.
Thanks again. I was kinda worried because of this "wiki" at reddit: https://www.reddit.com/r/audiophile/wiki/dirac , which points out to this thread stating the DDRC24 "poorly resamples" the souce to it's internal clock. I won't bother, then.
You have to look at the spectrum of that noise. All environments have high noise floor in bass since it penetrates through walls easily. But where our hearing is most sensitive -- 2 to 5 kHz -- rooms tend to be far quieter.As an example in this 24bit live acoustic recording the background noise at the start is around -60 to -50 dBfs. If I am reading the bit monitor correctly is around 12 bits of noise!
Just been having a quick look at the minidsp re-sampling as it converts all inputs to 48kHz or 96kHz for processing.
I input a sweep from 10Hz to 22kHz and looped it back (through USB) to see if there were any obvious SRC issues. All other DSP processing is turned off. Note this is not going through AD / DA conversion. A colourmap display is great for this as it makes the low level spuria stand out.
Original signal 44kHz - note the clean background
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Loopback - Has been converted to 48kHz. The images are around -130 dB so it looks worse than its audible impact. Interesting reflection abouve about 18kHz.
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48kHz input - clean
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Output, no SRC required. Noise floor increases to about -146dB from around -164dB but no spuria/images
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Adobe Audition conversion to 48kHz - Perfectly clean and no increase in noise floor. Much better than the miniDSP.
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Video of minidsp 44 to 48kHz sweep