1. Things you need to know about the new ‘Conversations’ PM system:

    a) DO NOT REPLY TO THE NOTIFICATION EMAIL! I get them, not the intended recipient. I get a lot of them and I do not want them! It is just a notification, log into the site and reply from there.

    b) To delete old conversations use the ‘Leave conversation’ option. This is just delete by another name.
    Dismiss Notice

Bizarre coax handshake issue

Discussion in 'audio' started by Alex S, Feb 14, 2020.

  1. Alex S

    Alex S carbon based lifeform

    I’ve just bought a Densen CDP from a member here to use as a transport. It’s lovely and it’s very nice to have one back in the system but the BNC > BNC to the Chord 2Qute Dac produced no sound. The cable is new from Mark Grant and he makes stuff properly but I tried another: BNC > RCA + BNC adapter, it’s all else I have. Nothing, although on both occasions the Chord dac showed red for CD but flickered slightly.

    The seller never used the player as a dedicated transport so he is not to know whether it works as such or not. I decided to try the Micromega Mydac I have lying around and it works just fine (BNC > RCA although if cables really are directional this is running the wrong way round).

    None of this really matters if the new dac I’m getting in a couple of weeks works but I’m wondering what the chances are and what might be going on with the Chord (or the cable I guess since I don’t have a BNC > RCA adapter only the other way round).

    Just to add, the cable working with the Mydac is the same second cable that didn’t work with the Chord, albeit with a BNC adapter on the end of it. Also, the Chord works fine with a Cambridge CXC transport and the very same (second) cable.

    Any thoughts? I hope I have explained this in a way that makes sense.
     
  2. thebiglebowski

    thebiglebowski pfm Member

    Suspect the Chord is having an issue locking on to the Densen's clock, may be that the Mydac or is more tolerent of slippage.
     
  3. Alex S

    Alex S carbon based lifeform

    Thanks. Can you elaborate slightly for the technically incompetent. Not blaming either product, do you suspect this being a Chord or Densen issue. I guess I’m asking, what are the chances of my new dac, Audial S4, working?
     
  4. thebiglebowski

    thebiglebowski pfm Member

    In order for the DAC to convert the digital to audio it needs to know where the 1's and 0's start and finish, it does this by synchronising it's own timing clock by using the clock signal from the source (densen CDP) If the Densen's clock source is drifting the Chord may be fairly strict on how much drift it will accept before it says bugger off. Clock drift results in noise and resolving clock drift results in jitter, both result in degraded sound and Chord may not want that whereas the Mydac isn't as strict/fussy.

    Could be a problem with the coax cable. I'd try another BNC cable before doing anything else.

    It would be fairly weird if the clock source in a Densen was that bad, how old is the Densen CDP?
     
  5. Alex S

    Alex S carbon based lifeform

    It’s a B410. Sounds surprisingly good via the Mydac actually. Having owned Densen in the past, they can be a bit flakey but this would be a surprise.
     
  6. i.j.russell

    i.j.russell pfm Member

    I had this problem with a Cyrus transport into a DDDAC. The Cyrus SPDIF out was not supplying enough signal for the DAC to sync properly. SPDIF is not an exact standard but operates within ranges. Sadly, there is only one way to find out if it works with your new DAC or not.
     
  7. thebiglebowski

    thebiglebowski pfm Member

    SPDIF is exactly a standard and a very specific one, more likely that Cyrus weren't following it.

    I always say that when it comes to voice with SIP there is an exact RFC specification for it that is implemented completely differently by the individual manufacturers.
     
    mansr and flatpopely like this.
  8. Alex S

    Alex S carbon based lifeform

    BNC being the better connection, would you think it’s more picky in this context?
     
  9. i.j.russell

    i.j.russell pfm Member

    The Standard says 0.6v max voltage but the Cyrus was putting out less and the receiver in the DAC expected very close to 0.6v. Other DACs I owned worked fine.

    BNC is better because the impedence of the connectors matches the 75ohm of the SPDIF specification whereas RCA connectors don't. I don't know whether it actually makes any difference in practice.
     
    torstoi likes this.
  10. thebiglebowski

    thebiglebowski pfm Member

    BNC or RCA makes zero difference in domestic audio.

    (I got banned from AoS for arguing with Marco as he claimed that BNC sounds much better than RCA)
     
    Barrymagrec likes this.
  11. Gaycha

    Gaycha pfm Member

    I did quick look on Denisen and got this:

    <<<The B-410 has double outputs, BNC digital output and Densen’s own Digital output format which allows for easy upgrade to separate DAC and Transport, if Densen decides to launch a separate DAC. The digital outputs can be switched off. It also has DenLink for easy communication between Densen products and for use in multiroom systems. The B-410 features a 24 bit type DAC. In addition upgrading is easy, the B-410 can be upgraded to the B-420 and to the B-440.>>>

    They have there own proprietary output format and code in a one output.

    Then I also saw this:
    <<
    To control the transport uses a completely new processor ATAPI, which serves the CD-drive, display, remote control system and a proprietary bus DenLink Drive. The program was written for him by experts Densen. They also supplemented the standard drive controller clock frequency, which allowed to use the common precision oscillator to synchronize transport, converters, and digital input and output streams. Thus was implemented one of the most effective ways to reduce jitter in digital playback devices.>>

    You may have luck contactng Denisen, but my feeling is they coded for their own dac upgrade routes, and that's why it's not talking to Chord DAC.
     
    torstoi likes this.
  12. Alex S

    Alex S carbon based lifeform

    Thanks for your research, really. Somehow I always sound sarcastic... I used to use a Densen 400 XS as a transport and it talked to anything I tried, but not Chord at the time. I’m now trying the 410 as a straight CDP and it’s rather good. The problem then is I’ll be using about three dacs (including TV optical) and might run out of preamp inputs and plug sockets (and money).

    I’ll have a chat with Mark Grant and see if he can lend me another BNC > BNC (but he makes to order I think), try everything again when the new dac arrives.

    Out of interest, does this mean the MyDac is so rubbish it doesn’t really care?

    PS Densen, Prince of Denmark.
     
  13. i.j.russell

    i.j.russell pfm Member

    I'll be interested in how you get on with the Audial; It's been on my 'to try' list for a while.
     
  14. Gaycha

    Gaycha pfm Member

    Just means it works and is not fussy. Can be hit or miss with some custom code and drivers, doesn't take much to get a conflict then no handshake.
     
  15. Alex S

    Alex S carbon based lifeform

    I’ve bought the Audial totally blind so I’m quite interested too. I had a few Metrums in the past and like NOS done well. It’ll get a 5 star review just for talking to the damn Densen.
     
    torstoi likes this.
  16. Blackmetalboon

    Blackmetalboon pfm Member

    @Alex S I had a similar issue with a Chord DAC, in my case it turned out to be a tiny bit of fluff on the BNC input that resulted in the DAC not being able to lock.
     
    Gaycha likes this.
  17. Alex S

    Alex S carbon based lifeform

    Thanks, will de-fluff in the morning, bit tired now zzz

    Of course I had to try. Not fluff, sadly.
     
  18. davidsrsb

    davidsrsb pfm Member

    SPDIF is a one way transmission. Any handshake protocol is not SPDIF.
     
  19. Mr Pig

    Mr Pig ^'- -'^

    How do you work that out? I read about the differences length of cable and connector type made and saw nothing about it only being applicable to..what exactly? Pro audio?
     
  20. thebiglebowski

    thebiglebowski pfm Member

    BNC was made popular by the military as the connector was good in environments where vibration, moisture and sand etc are an issue. It was designed to provide a very good impedance match and reduce signal reflections.

    None of those are an issue in domestic audio.
     
    mansr, Gaycha and i.j.russell like this.

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice