Latest post Tue, Jun 19 2018 10:59 PM by callahoohoo. 7 replies.
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  • Sat, Apr 22 2017 10:19 PM

    • doxilia
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    Nitris DX/Symphony Communication

    After having our Nitris DX in operation for almost 10 years, I thought it would be high time to open it up again and not only give it a good dusting but also to replace the rather old and noisy 80 mm Delta main system fans. I decided to pick up a pair of Austrian designed Noctua fans which are very nicely made and extremely quiet. However, these fans don't have the same specs as the original Delta's (RPM speed is lower in the replacement fans). More on this to follow.

    In addition, there is a 40 mm PSU cooling fan which sounds like a turbine when powered up and given the hard mounting to the metal PSU chassis which in turn makes contact with the main fan metal support "leaf", the sound the NDX was emitting had some nice harmonics producing beats in the 90 dB range..., borderline unusable I/O box unless rectified. Actually, one could argue a health hazard. In short, I replaced this fan too and while the overall cooling might not be quite as effective as it was before, the unit is virtually dead quiet and I actually can hear my timelines now! I couldn't wipe the grin off my face after connecting everything and powering up.

    I won't go further into the hardware and noise issues but I wanted to lay down the foundation for my questions. Why? Because Symphony is now complainig intermittently about a "fan malfunction" and stops timeline or clip playback. Clearly, there is no fan malfunction because all three are working perfectly well. But..., evidently NDX communicates in some fashion (over the PCIe bus) with SYM telling it that there is a problem. Of the three fans, only the main two PCB 80 mm fans are three pin and are therefore in principle speed controlled by the NDX hardware. The PSU fan is a two pin fan powered internally by the PSU so it is not controlled by the PCB nor has direct communication with it other than possibly through the 20 pin molex power connector to the NDX hardware. So, with that out of the way, I was hoping someone with NDX hardware knowledge could help answer the following:  

    1) How does the NDX box communicate with SYM at the fan "malfunction" level?


    2) Does the communication only happen between system controlled 3-pin fans (i.e., the main fans) or is the system also monitoring the PSU fan through the 20 pin connector?


    3) What does the NDX hardware expect in terms of fan performance/specs? Is it RPM based only or is there more to it?


    4) If I know the now quiet NDX box is operating properly without excessive heat (I haven't noticed the passive chip heatsinks or the PSU overheating after having the system on for a day), is there a way to disable this notification in software (e.g., through the console) which prevents proper functionality of the software?

    Any insight or advice is much appreciated.

    Thanks, David 

     

     

  • Sun, Apr 23 2017 10:13 AM In reply to

    • Bruno M
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    Re: Nitris DX/Symphony Communication

    Hi David.

    Whilst I know very little about the internal workings of the NDX, I have some experience of putting fans into computer cases.

    As you're probably aware, fans can have anywhere between 2 and 4 connectors. These pins usually follow the same standard, in that pin 1 is ground, pin 2 is +ve, pin 3 is the sense output from the fan and pin 4 is the (PWM) control input.

    If we assume that Avid follows this convention, the 3 pin fans inside the NDX are sending rotary information to the NDX boards via pin 3 on the fan. You mentioned that your replacement fans have a lower rotational speed to the originals, and this may be your problem. It may be that your fans are being speed-controlled , which can be simply done with DC motors by varying the voltage on pin 2. However, when the NDX hardware/firmware thinks it needs maximum cooling, it's going to send the max voltage (12 volts) to the fans and expect them to come to full speed. Given that your fans won't reach these speeds, the circuitry will detect this problem via pin 3 and do whatever the firmware is designed to do - in your case it stops Symphony with an error message.

    Where this problem happens in DIY computer builds, it's sometimes possible to change fan settings in the BIOS, but since there seems no way of accessing anything like BIOS/setup menus in NDX, I suspect your options are limited. You mentioned console settings, but I've never seen any published settings that allow you to get into the inner workings of the NDX. Avid normally seem to do this via a firmware update, which you may have noticed when you've updated the software, but I wouldn't rate your chances of getting a modified firmware update from Avid engineering!

    I suspect your only remaining options are to get hold of fans that run as fast as your original fans, or to service the original fans (bearing lubrication/replacement).

    Bruno

    HP Z800, HP G3 Studio, SonnetFusion RAID, Mojo DX, Symphony 2018.9, JVC DTV1910 HD tube monitor, HP Dreamcolor, Avid Artist Color [view my complete system specs]
  • Sun, Apr 23 2017 8:37 PM In reply to

    • Sharney A
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    Re: Nitris DX/Symphony Communication

    Hi David

    I had trouble concentrating in our online suite with a DX box right in front of me, our engineer replaced all three fans with the same make you mention and Avid Symphony after an hour came up with the same alert.  The engineer then looked up the original fan specs and replaced them almost like for like in terms of speed and air flow it now runs whisper quiet.

    ill see if we have the document and pop it on here.  I think we had to go with two manafacturers.

    MacPro 3GHz 8 Core Intel Zeon E5, 32GB Ram, Dual D700 6GB, Avid Artist DNxIO, Avid Media Composer V8.7.2 with Symphony Option. [view my complete system specs]
  • Sun, Apr 23 2017 9:18 PM In reply to

    • Lukas Boeck
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    Re: Nitris DX/Symphony Communication

    and i live 2 streets from noctua HQs (no ***!)

     

    i can go see if they have still have any 2-pin fans left. Smile

    MC 8.4.4 Cusom bulid Supermicro X9SRL-F, 32 Gig Ram, 3ware 9750 6x6TB Seagate EC Drives, LSI 9207 + LTO-6, Mojo DX, Artist Color, Flanders CM240, GTX 1070... [view my complete system specs]
  • Wed, Apr 26 2017 8:42 AM In reply to

    • Mondo
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    Re: Nitris DX/Symphony Communication

    Bruno M:
    Where this problem happens in DIY computer builds, it's sometimes possible to change fan settings in the BIOS, but since there seems no way of accessing anything like BIOS/setup menus in NDX, I suspect your options are limited. You mentioned console settings, but I've never seen any published settings that allow you to get into the inner workings of the NDX. Avid normally seem to do this via a firmware update, which you may have noticed when you've updated the software, but I wouldn't rate your chances of getting a modified firmware update from Avid engineering!

    With a little electronics knowledge you could "trick" the Avid box into thinking the fan is running at full speed. First you would have to measure the sense voltage on the original fans at both normal and full speed (I'm assuming here that the NDX hardware probably only runs at two speeds - normal and full bore). Then you would have to measure the sense voltage of the new fan at what you consider normal and full. As it only seems to have problems with full you could just concentrate on stepping that voltage up so that it matches the original fans. We are talking mV here so I imagine it wouldn't need to be a big adjustment. 

    Of course if you can just buy much quieter fans that match the rotational speeds of the originals I think that would be a lot easier.

     

    HP Z820 16GB RAM Winx64Pro SP1/Xeon 2620 x 2/Quadro 4000 NitrisDX, Fiber client Unity client 5.3 Build 15440, 4 bay SSD dock (Addonics) Custom build: Asus... [view my complete system specs]

    John

    Can we go back to the way audio nodes used to be selected? Please? ie if you have audio nodes at the same time on selected tracks; then selecting 1 audio node selects them all at that time. Having to shift select nodes or add an in and out is time consuming and counter productive. At least make it an option.

  • Wed, Apr 26 2017 9:13 AM In reply to

    • Bruno M
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    Re: Nitris DX/Symphony Communication

    Mondo:
    With a little electronics knowledge you could "trick" the Avid box into thinking the fan is running at full speed. First you would have to measure the sense voltage on the original fans at both normal and full speed (I'm assuming here that the NDX hardware probably only runs at two speeds - normal and full bore). Then you would have to measure the sense voltage of the new fan at what you consider normal and full. As it only seems to have problems with full you could just concentrate on stepping that voltage up so that it matches the original fans. We are talking mV here so I imagine it wouldn't need to be a big adjustment.

    I'm pretty sure this wouldn't work. As far as I'm aware, pin 3 sends pulses based on it's rotational speed (2 pulses per revolution) and this is what computer motherboards read, not the value of the voltage on that pin.

     

    HP Z800, HP G3 Studio, SonnetFusion RAID, Mojo DX, Symphony 2018.9, JVC DTV1910 HD tube monitor, HP Dreamcolor, Avid Artist Color [view my complete system specs]
  • Thu, Apr 27 2017 3:45 AM In reply to

    • doxilia
    • Top 500 Contributor
    • Joined on Thu, Oct 13 2005
    • Montreal, Canada
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    Re: Nitris DX/Symphony Communication

    Fellas,

    thanks for all the replies. It's good to hear that I'm not the only one who found the NDX alarmingly loud. Of course, when it's in a server room, one probably doesn't know or care but when it's in the suite...

    Sharney, info on your final replacement units would be helpful. The Noctua's are really nice fans so it's going to be a shame to have to pull them. I looked up the specs of the original Delta's but couldn't find the specific model in my NDX on their site. Generally, similar model numbers had higher RPM and airflow.

    Question: did your engineer know or measure whether RPM info is being passed to/from the PSU 2-pin fan (i.e., in principle no RPM or other info being communicated) to the circuit boards through the 20-pin power connector? This is actually my main concern as it was the loudest (and fastest) fan of all.

    I've already serviced the old Delta fans so they should be quieter than they were. I guess the next step would be to put them back in and see if the firmware problem goes away. If it does, the next thing would be to actually know or measure what RPM the NDX expects out of these 3-pin fans (I doubt there is any way for it to detect airflow).

    I actually tried a couple of strobe tachometer phone apps to see what RPM the Delta's (and PSU fan) were turning but they are rather crude and don't give particularly accurate results. With that in hand, perhaps I can source a pair of similar spec better quality fans. I think my 80 mm Delta's turn 1800 RPM while the Noctua's that I picked up are 1200 RPM (intentionally chosen as I knew they would be quiet) but I guess this is proably too low for the NDX to be happy.

    David 

  • Tue, Jun 19 2018 10:59 PM In reply to

    Re: Nitris DX/Symphony Communication

    Hey David,

    Can you tell me the models of the fans you used for replacment?  I'd love to do this, myself.  For the 80mm, I know that Noctua has the PWM, FLX (multiple speeds), and ULN (ultra low noise / slow fan).  The PWM has a 4pin connector but would still work, but don't know if the FLX would...

    As for the 40mm, that's the loudest part by far!  I'd love to know what you used there.

    Thanks

    Ben

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