New Posts  All Forums:

Posts by razvitm

Just finished running some RMAA tests on several portable minidisc recorders. Hardware: Asus X99A onboard soundcard optical out set to 16 bit 44.1 khz E-MU0404 USB analog input set to 24 bit 44.1khz Put a blank disc in your minidisc recorder Start the RMAA test Push record without pushing simultaneously play The player starts to output through headphone out what you feed it through optical in jack Adjust levels both on player, usually a few values below max, and on...
All minidisc recorders, portable or not, can take an optical signal and output it to headphone out jack.
Does anyone use a portable minidisc recorder as a DAC?
Some of them have built-in sample rate converter, they accept both 44,1KHz and 48KHz optical spdif. You can fool the player that you want to record, it starts converting the digital stream and outputs audio to line-out so you can set recording levels, and you keep the player in this state, you don't start the actual burning of the disc. I'm at work at the moment, but when i get home i will try this with my sharp and sony minidisc players, maybe run some RMAA tests on...
I used headphone out on the players with only one output jack and i used line out jack on the x3 and x3 because line-out has less noise than headphone out.
I found the dither on off setting, but how do I disable noise shaping in rockbox on the xduoo x3?
The bttom line question is: Using a high quality soundcard and a jack to jack cable, how do you test, or what do you do, to prove that the xduoo x3 with rockbox has 24 bit support or not? Can a home user prove the xduoo works in 24 bit mode in rockbox?
Do you have any idea what a noise ground floor is and what it looks like on a graph?
The analog part of the internals can only handle the equivalent noise of 21 bits... 
I have a technical question about rockbox on the xduoo x3... Did a comparison between various DAPs with RMAA. Devices that have 16 bit DACs have a noise floor of about -130dB. Devices that have 24 bit DACs have a noise floor of about -140dB. The xDuoo X3 scored -107dB SNR and a -140dB noise floor using rockbox playing a 24bit 44.1KHz rmaa test file. The question is, if rockbox doesn't support hi-res, why is the noise floor -140dB instead of -130dB and why is the SNR...
New Posts  All Forums: