USB Bridge

Discussion in 'DACs' started by stoutblock, Dec 9, 2017.

  1. gvl

    gvl Well-Known Member

    Messages:
    990
    I don't think that statement is true. Flac's algorithm relies on being able to recognize PCM data in a binary stream such as the sampling rate and bit-depth to run the compression, just a text file won't do.
     

     

    Please register to disable this ad.

  2. for_p1

    for_p1 Addicted Member

    Messages:
    5,467
    Location:
    North TX
    Just put text into WAV container with SOX or specify all parameters as command attributes.
     
  3. gvl

    gvl Well-Known Member

    Messages:
    990
    WAV container isn't a text file. If you are saying you can compress a WAV file containing noise sure, but it is not the same as compressing a text file.
     
  4. stoutblock

    stoutblock If it sounds good, it is good... Subscriber

    Messages:
    9,456
    Location:
    Northwest USA
    I agree the U208 sounds even better than the U8. The U8 bridge I owned (Audio-gd DI-U8) sounded great but the Breeze U208 is even better. Basically more of the same.
     
  5. for_p1

    for_p1 Addicted Member

    Messages:
    5,467
    Location:
    North TX
    See below:

    user@king2:~$ cat 6ac7-spice.txt
    .SUBCKT 6SJ7 A G2 G1 K
    BGG GG 0 V=V(G1,K)+0.40161932
    BEP EP 0 V=URAMP(V(A,K))+1e-10
    BEG EG 0 V=URAMP(V(G1,K))+1e-10
    BEG2 EG2 0 V=URAMP(V(G2,K))+1e-10
    BM1 M1 0 V=(0.02462593*(URAMP(V(EG2)-1e-10)+1e-10))**-0.84287662
    BM2 M2 0 V=(0.64023858*(URAMP(V(GG)+V(EG2)/14.609049)+1e-10))**2.3428766
    BP P 0 V=0.0011655656*(URAMP(V(GG)+V(EG2)/22.818133)+1e-10)**1.5
    BIK IK 0 V=U(V(GG))*V(P)+(1-U(V(GG)))*0.00071703729*V(M1)*V(M2)
    BIG IG 0 V=0.00068041382*V(EG)**1.5*(V(EG)/(V(EP)+V(EG))*1.2+0.4)
    BIK2 IK2 0 V=V(IK,IG)*(1-0.4*(EXP(-V(EP)/V(EG2)*15)-EXP(-15)))
    BIG2T IG2T 0 V=V(IK2)*(0.78466568*(1-V(EP)/(V(EP)+10))**1.5+0.21533432)
    BIK3 IK3 0 V=V(IK2)*(V(EP)+12950)/(V(EG2)+12950)
    BIK4 IK4 0 V=V(IK3)-URAMP(V(IK3)-(0.00044226898*(V(EP)+URAMP(V(EG2,EP)))**1.5))
    BIP IP 0 V=URAMP(V(IK4,IG2T)-URAMP(V(IK4,IG2T)-(0.00044226898*V(EP)**1.5)))
    BIAK A K I=V(IP)+1e-10*V(A,K)
    BIG2 G2 K I=URAMP(V(IK4,IP))
    BIGK G1 K I=V(IG)
    * CAPS
    CGA G1 A 0.005p
    CGK G1 K 3.6p
    C12 G1 G2 2.4p
    CAK A K 7p
    .ENDS

    user@king2:~$ flac --endian big --sign signed --channels 1 --bps 8 --sample-rate 8000 6ac7-spice.txt

    flac 1.3.1, Copyright (C) 2000-2009 Josh Coalson, 2011-2014 Xiph.Org Foundation
    flac comes with ABSOLUTELY NO WARRANTY. This is free software, and you are
    welcome to redistribute it under certain conditions. Type `flac' for details.

    6ac7-spice.txt: wrote 9107 bytes, ratio=N/A

    user@king2:~$ ls -l 6ac7-spice.*
    -rw-rw-r-- 1 user user 9107 Jun 8 2013 6ac7-spice.flac
    -rw-rw-r-- 1 user user 969 Jun 8 2013 6ac7-spice.txt

    user@king2:~$ file 6ac7-spice.flac
    6ac7-spice.flac: FLAC audio bitstream data, 8 bit, mono, 8 kHz, 969 samples

    user@king2:~$ flac -d --endian big --sign signed --force-raw-format 6ac7-spice.flac

    flac 1.3.1, Copyright (C) 2000-2009 Josh Coalson, 2011-2014 Xiph.Org Foundation
    flac comes with ABSOLUTELY NO WARRANTY. This is free software, and you are
    welcome to redistribute it under certain conditions. Type `flac' for details.

    6ac7-spice.flac: done

    user@king2:~$ ls -l 6ac7-spice.*
    -rw-rw-r-- 1 user user 9107 Jun 8 2013 6ac7-spice.flac
    -rw-rw-r-- 1 user user 969 Jun 8 2013 6ac7-spice.raw
    -rw-rw-r-- 1 user user 969 Jun 8 2013 6ac7-spice.txt

    user@king2:~$ cat 6ac7-spice.raw
    .SUBCKT 6SJ7 A G2 G1 K
    BGG GG 0 V=V(G1,K)+0.40161932
    BEP EP 0 V=URAMP(V(A,K))+1e-10
    BEG EG 0 V=URAMP(V(G1,K))+1e-10
    BEG2 EG2 0 V=URAMP(V(G2,K))+1e-10
    BM1 M1 0 V=(0.02462593*(URAMP(V(EG2)-1e-10)+1e-10))**-0.84287662
    BM2 M2 0 V=(0.64023858*(URAMP(V(GG)+V(EG2)/14.609049)+1e-10))**2.3428766
    BP P 0 V=0.0011655656*(URAMP(V(GG)+V(EG2)/22.818133)+1e-10)**1.5
    BIK IK 0 V=U(V(GG))*V(P)+(1-U(V(GG)))*0.00071703729*V(M1)*V(M2)
    BIG IG 0 V=0.00068041382*V(EG)**1.5*(V(EG)/(V(EP)+V(EG))*1.2+0.4)
    BIK2 IK2 0 V=V(IK,IG)*(1-0.4*(EXP(-V(EP)/V(EG2)*15)-EXP(-15)))
    BIG2T IG2T 0 V=V(IK2)*(0.78466568*(1-V(EP)/(V(EP)+10))**1.5+0.21533432)
    BIK3 IK3 0 V=V(IK2)*(V(EP)+12950)/(V(EG2)+12950)
    BIK4 IK4 0 V=V(IK3)-URAMP(V(IK3)-(0.00044226898*(V(EP)+URAMP(V(EG2,EP)))**1.5))
    BIP IP 0 V=URAMP(V(IK4,IG2T)-URAMP(V(IK4,IG2T)-(0.00044226898*V(EP)**1.5)))
    BIAK A K I=V(IP)+1e-10*V(A,K)
    BIG2 G2 K I=URAMP(V(IK4,IP))
    BIGK G1 K I=V(IG)
    * CAPS
    CGA G1 A 0.005p
    CGK G1 K 3.6p
    C12 G1 G2 2.4p
    CAK A K 7p
    .ENDS
     
  6. gvl

    gvl Well-Known Member

    Messages:
    990
    Fair enough, although close to 10x flac file size as compared to the original txt doesn't quite strike me as compression.
     

     

    Please register to disable this ad.

  7. for_p1

    for_p1 Addicted Member

    Messages:
    5,467
    Location:
    North TX
    Metadata + headers. You need a much bigger file than 969 bytes to see some compression.
     
  8. GChief

    GChief AK Subscriber Subscriber

    Messages:
    1,413
    Location:
    Eastern NC
    So being that I am a semi old crusty tech and follow most of these threads trying to learn some digital audio stuff I have noticed 2 sides to these discussions. 1) A digital signal is a digital signal. 2) The digital audio signal is from heaven there for special. Now this is just the opinion of someone with over 30 years chasing ones and zeros through Sonar equipment and I am probably wrong, I hear and understand all the examples but I tend to be a believer in #1 so far. If I am way off I apologize.

    :beerchug:


    Gates.gif
     
    Last edited: Dec 13, 2017
  9. MurrayLives

    MurrayLives Born to lose, live to win Subscriber

    Messages:
    534
    Location:
    Philadelphia
    Breaking out the old NEETS modules, @GChief ?
     
  10. GChief

    GChief AK Subscriber Subscriber

    Messages:
    1,413
    Location:
    Eastern NC
    Sort of :D. In my non-EE brain it doesn't matter if it's diodes, resistors and transistors or chips making the ones and zeros, the signal is still just 1's and 0's.

    :beerchug:
     
  11. BobHol

    BobHol Old fart Subscriber

    Messages:
    632
    Location:
    Fort wayne IN
    :lurk: Wow, I am an old fart who never really understood how a transistor does its thing. I am in the process of upgrading from behringer 202's and hope to be able to hear some difference after installing a Topping D30. I compare this to back in the day moving up from cheap BSR and Garrard changers to a Dual with a nice shure cartridge. I love being able to store all of my music on a digital format so there is no way to avoid the digital to analog interface. But I never really upgraded very far above the Dual TT and I don't plan on spending big dollars ($200 for any one piece really slows me down) for digital audio
     

     

    Please register to disable this ad.

  12. stoutblock

    stoutblock If it sounds good, it is good... Subscriber

    Messages:
    9,456
    Location:
    Northwest USA
    Yeah that’s right, it is just 1s and 0s, and vinyl is just a grove pressed in plastic....
     
    botrytis likes this.
  13. GChief

    GChief AK Subscriber Subscriber

    Messages:
    1,413
    Location:
    Eastern NC
    Sweet people are starting to get it
    :banana::beerchug:
     
  14. stoutblock

    stoutblock If it sounds good, it is good... Subscriber

    Messages:
    9,456
    Location:
    Northwest USA
    Well my system has all those 1s and 0s polished to a very pretty shine right now :beatnik:
     
    Last edited: Dec 14, 2017
    ldatlof and GChief like this.
  15. gvl

    gvl Well-Known Member

    Messages:
    990
    After all I decided not to take my chances with the Breeze Audio unit mainly because of the missing drivers for W7 and bought a pre-owned Matrix Audio X-SPDIF 2: http://matrix-digi-usa.com/x-series/x-spdif_2 . About 2x the price of the top-level Breeze but solid build, can run off USB or external power, official drivers. Won't comment on how it compares to the previous gen of XMOS or other USB interfaces but it is a definite improvement over Toslink out of a laptop Creative Sound Blaster card which I thought sounded kind of lean and on the bright side, and indeed the gains in the low-end and low mid-range are huge. So much for the "bit-accurate" playback mode on the sound card. The DAC itself doesn't have a USB input, so this purchase was "justified" :)
     
  16. gvl

    gvl Well-Known Member

    Messages:
    990
    Well, turned out I was barking up the wrong tree. The CCA and the newly acquired DDC sound much closer so it was the SPDIF out of my sound card messing with my brain. The CCA is fine and "compressed and congested" is how it was supposed to sound. My apologies for the noise.
     

     

    Please register to disable this ad.

  17. gvl

    gvl Well-Known Member

    Messages:
    990
    One issue I'm finding annoying is that I can't force the DDC to operate in 16 bit/44.1kHz, or advertise itself as such a device on Windows. Basically it gives an option for apps to pick a mode that is not compatible with the downstream DAC. Generally not an issue with powerful players like JRiver where you can fully control the output mode, but say Tidal Masters MQA->PCM transcoder appears to pick a mode that's incompatible with my vintage DAC (48kHz/16bit max) resulting in weirdness. While it is probably not a very good idea to use a vintage redbook DAC with Tidal masters, for Tidal HiFi I can only hope than the app doesn't dither 16 bits to 24 bits as the DAC just drops LSBs on the floor. Sigh.
     
  18. olson_jr

    olson_jr AK Subscriber Subscriber

    Messages:
    13,604
    Location:
    Pilgrim Hills Michigan
    Damn, I came to this thread because I thought it would be about USB Bridge's.

    Instead, we get sidelined with talk about CCA, MQA, FLAC, ZIP & BS.

    Sad.
     
  19. stoutblock

    stoutblock If it sounds good, it is good... Subscriber

    Messages:
    9,456
    Location:
    Northwest USA
    Ha such is paradise! Back to subject, I’ve had my Breeze now for several weeks. I have never had an electrical component so sensitive to warm up! I just leave it on 24/7 now as it really takes a couple of hours to blossom. I am thinking of replacing the electrolytic caps with something known. Not that it would improve the sound it is just that I don’t know what is in there now as they have no brand label, just rating. I assume something out of China that may or may not be of any quality? I just like to know what I have and they are something of known quality.
     
    olson_jr likes this.
  20. bazarimajom

    bazarimajom Member

    Messages:
    54
    Location:
    Hungary
    I have the Talema version, on the PCb there is XMOS U208 V1.1. There are 4 1500uF 16V elcos, 1 47uF 25V (on the PCB the marking shows 100uF), these are black and gold labels, unknown brand. There is also another 47uF 6.3 or 16V Oscon looking elco. I replaced the 1500uFs with Nichicon KA 2200uF 25Vs, the 47uF with Nichicon FG 47uF 25V, and as I couldn't see the 47uF marking on the oscon like cap, I replaced it with a 100uF as it was marked on the board, I think it was also FG I had on hand. My impression is that the bass became more controlled, less boomy. I think it is still better than unknown quality caps so it's worth the little money and time invested. I'm also thinking about bypassing the power switch so when you plug the power cord it will be always on, but I didn't decide on this yet.
     

Share This Page