Jump to content

davidm

Members
  • Content count

    168
  • Joined

  • Last visited

About davidm

  • Rank
    Hero Member
  • Birthday 02/05/1956

Profile Information

  • Location
    Auckland, New Zealand
  • Interested in Sound for Picture
    Yes
  • About
    Sound Mixer
  1. Tablet running Wireless Designer

    I power my tablet from a 12 volt to USB power adapter which has 4 outputs for charging other stuff as well. However, this all has to be powered via a DC-DC converter to run it off my cart power to prevent computer garbage noise from getting into the audio system.
  2. Tablet running Wireless Designer

    I have been running a low cost Windows 10 tablet (Linx 1010B 10.1 inch - Intel Atom Z3735F Quad Core) for about a year for use with Wireless Designer and a Wideband Venue along with running Ambient’s ACN network. I purchased the Linx 1010 as it has 2 standard USB ports plus a micro USB port for charging. I use one USB port for connection to the Venue and the other for other uses such as a SD card reader or connecting to my Cantar X3 via a network adapter. Wireless Designer works fine for me but it’s more a remote viewer rather than a control for the Venue. The lowish resolution screen and the vague touch screen response doesn’t really translate into an elegant and versatile computing experience. Perhaps a Microsoft tablet would be preferable and I’d consider that as an option if the Linx tablet died.
  3. studio fans...

    A 24" is the quietest Mole as it can operate at a lower speed compared to smaller size fans for the same airflow. The problem that I experience with Mole fans isn't the noise they make when gently blowing an actors hair, it's the additional background fans deemed necessary to move background leaves on trees, curtains, etc. The artful wafting of a cutter does not appear to be in anyones job description these days.
  4. So who showed what at NAB

    Dante Broadway 8x8 & 16x16 chips. These chips bridge the gap between the current 4x4 and 32x32 Dante chips and better suit location audio equipment channel counts. https://www.audinate.com/products/manufacturer-products/dante-broadway?link=h-car
  5. Your first sound setup or kit ever

    First kit purchased in 1985: Nagra 4.2, Sennheiser 416 in a Rycote basket, Beyer DT48. First kit operated - 1977, ABC Brisbane, Australia: Nagra 4.2, Sennheiser 815 & 2 x 415, Rycote baskets, EV 667, a couple of really big Sennheiser lavaliers and DT48's
  6. I stand corrected regarding the roller shutter on the Arri's, but I'm told it's damn near a global shutter.
  7. Genlocking via timecode is Arri's recommended practice. It's noted in the current Alexa Mini and Amira manuals and firmware notes. TImecode works in this instance because the camera has a global shutter and the TC is triggering a single full sensor read of each frame rather than a traditional and more complex TV scanning sequence. The Alexa and a Mini with the genlock via BNC mod can use black burst or Tr-level sync as an alternative. The only caveat with using TC as genlock is that a stable, high quality generator must be used.
  8. Aaton XTR sync start/stop

    Aaton Code is on the edge of the film outside the scanned picture area. There is no way to use this timecode without the Aaton Code hardware reader on the telecine machine. If the telecine has the reader then as Bash notes above, you can have that timecode burnt into the vision. Without the Aaton code reader on the telecine, the only practical way to sync the film with audio is with a slate, either plain clapsticks or a timecode slate.
  9. Aaton XTR sync start/stop

    The "Aaton code" is the same SMPTE/EBU timecode format that is used in audio files of the currently available professional audio recorders. If you have the technology to read the Aaton code from the film - a telecine with the Aaton timecode Keylink hardware reader and the Keylink / Indaw software, you can sync audio with matching timecode to the film. Alternatively, you could output the video though the Keylink hardware reader and software and then sync the audio in and Avid, FCP or Resolve.
  10. Oscar Technical Award BS.

    Lectrosonics Digital Hybrid does not transmit analogue audio! The scheme uses FM modulation to transmit a digital signal. Note that it is a digital signal, not a complete stream of compressed or uncompressed digital audio. From Lectrosonics White Paper on the subject: "The audio entering the transmitter is first sampled at 88.2 kHz and converted to a 24-bit digital audio stream. The digital audio is analyzed by a DSP-based algorithm that attempts to predict the next audio frames on a continuing basis. The prediction is then compared to the actual audio stream that follows and a difference (error) signal is generated. The error signal is delivered to the output of the transmitter and transmitted with a wide deviation FM modulation. A compandor is applied to the error signal to improve the signal to noise ratio of the radio link, but no compandor is applied directly to the audio. Inside the receiver the same predictive algorithm is operating. The error signal is received and then applied to the predicted audio stream to restore the original digital audio stream. The 24-bit digital audio is then converted back into an analog audio output" It is an innovative transmission scheme in it’s own right and thus patended (applied for in 2002).
  11. Mac mini 2012 DC input specs

    My first G4 Mac Mini 12volt DC power setup was with a Carnetix system. The fan was a bit loud for my liking. The Carnetix powe supply was designed for the the G4 and early Intel Mac Mini's which needed around 18 volts to boot. Wouldn't reccomed for the 2010 onwards 12 volt Unibody Mac Mini's.
  12. Mac mini 2012 DC input specs

    The Unibody Mac Mini's will run on a wide range of DC input voltages. The mod removes the internal AC supply and then makes a direct connection from an external DC supply to the Mac Mini's main board which no doubt has it's own DC-DC conversion. My 2010 and 2012 models would work just fine off the over 17 volts of a freshly charged V-Lock battery. However.... Depending on what is installed in the Mac Mini such as hard drives, SSD's and RAM, basic current draw can be in the range of .8 to 1.5 amps at 12 volts or 10 to 20 watts. If using a regulated supply, the crunch occurs during boot as current draw can peak at over 4 amps. If you are using a bus powered audio interface then you need to build that into the equation. The mains power supply is rated at over 80 watts to cope with the boot requirements and whatever the user has added in the way of external firewire and USB devices. I ran a Metacorder setup for 10 years and found that I had to use DC-DC converters to fully float the Mac Mini power supply or there would be some level of bus noise introduced into the audio system. I used Traco converters and settled on 60 to 100 watt versions at 12 or 15 volts to get through the boot phase. My audio interface for most of the 10 years was a Metric Halo 2882 that was powered separately. A ground lift firewire cable was required between the Mac Mini and the 2882 to be relatively noise free. USB bus noise can also be problematic. There are a couple of so called audiophile companies that have made filter and regulated DC supply boards that fit in the place of the AC supply but I haven't tried any of those. David (2 Metacorder Licenses / Dongles for sale! PM if interested)
  13. Zaxcom High Density Wireless

    Will the new transmitters have reduced RF power outputs that function in ZHD mode? If so, does a 3db or 6 db drop in the RF output power of the RF linear amplifier result in a significant drop in battery power consumption? If the extended operating range isn't needed then longer battery runtime would be worthwhile.
  14. 130V : Microphones

    The Nagra 4SJ instrumentation recorder of the 1970's could be ordered with B&K mics which ran on 200 volts if my recollection is correct. The Nagra had a voltage converter inside for the 200 volts.
  15. Alexa Mini TC sync

    This is my first shoot with the Alexa Mini and I have Tiny Lockit's on full time. There's no reason to expect the Mini to have any lesser TC stability than a standard Alexa if jamming every half day.
×