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Postovi objavljeno od Mikorist

    AD1865 / AD1862 / PCM63P NOS USB DAC (blast from the past)

    in Digital

    Napisano

    Design Philosophy Metrum Acoustics.pdf

     

    Screenshot 2022-09-05 at 04.39.06.png

    Picture above is a part of our ears. It concerns the cochlea with is located in the inner ear. Every spot in the
    cochlea is sensitive to a certain specific frequency. The highest frequencies are registered at the front while
    the lowest are registered at the end of the cochlea. The basilar membrane, which is part of the cochlea,
    functions as a base for 15 to 20 thousand hair cells. Each of these hair cells are connected to a nerve which
    is connected to the brain. This is only a (very) short summary of the working of the ear because in truth, the
    ear is infinitely more complex. We however will limit ourselves to the sensory cells (hair cells) that each have
    describe a limited range of frequencies in such a way that they all overlap. The sum of all of these determines
    the range of our hearing, which on average is between 20 Hz and 20.000 Hz. With 20.000 hair cells their
    bandwidth is very small and thus very selective. This means that for one specific hair cell, except the specific
    frequency that it is tuned to, a signal gets filtered out at 40 dB per octave. This means that our hearing on this
    level behaves much like a band-pass filter, comparable to the filters found in CD-players. Implementing filters
    of this level in a CD-player can thus be described as overkill. 

    Because the basilar membrane behaves as a sharp filter for our hearing, it has become, in a certain way, part
    of the DAC. The measurements on a NOS DAC are therefore not measured at its logical end-point, but
    before the filter (our hearing). Herein lies the problem, which exists when comparing the actual time domain
    results and the way in which the Jtest interprets and shows results. 

     

    Screenshot 2022-09-05 at 04.57.13.png

    Pa zar nije tako - da je Vudu ?

    Ako treba da prebrojavamo koliko ko ima dlačica u sredmjem uhu - mi preko 45 godina imamo manje od 15.000 - filtriranje je još jače :smesna:

    Mini pretpojačalo sa OP

    in Solid State

    Napisano

    pre 8 časa, NIXIE reče

    U principu single OPA bi imao više smisla da se rade dva odvojena napajanja za analogni deo, kako za analogni deo PCM63 tako i za I/U. Miro je ostavio džampere da se to može izvesti, pa ko voli da troši ...

    Dual OPA ima više smisla kad je jedno napajanje analognog dela.

    Postoji li neka bitna razlika sa odvojenim napajanjima, ne znam. Verovatno je ima ali je minimalna.

    Ama ovo radi kao babaroga ovako kako je dekuplirano u DAC.....Miro kaze da ne trebaju odvojena napajanja - on ne cuje razliku :smesna:

     

    Ti ako hoćeš ti stavi još jedan PSU2 pa ćeraj oba OPA zasebno...ali to košta burazeru....i ovo ovako je mnogo :risitas:

    Serije koje gledate

    in Muzika , Film i Fotografija

    Napisano

    pre 47 minuta, Doktor reče

    ^

    Ovaj clanak je jos jedan dokaz propasti srpskog novinarstva. 

    Resavska skola, bolje reci kompilacija kritika iz svetskih ( citaj : US & UK glasila ). Najvrediniji su ovde komentari nasih citalaca koji daleko vise govore o RoP tv seriji. 

    :coffee:

     

    Isti tekst i na Kuriru

    https://www.kurir.rs/zabava/pop-kultura/4002877/stigle-prve-kritike-najskuplje-serije-u-istoriji-gospodar-prstenova-prstenovi-moci

    doslovno prepisano jedno od drugih:smesna:

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