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RScottATL

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    Atlanta, GA
  • About
    Purveyor of Fine Sounds and Radio Waves, ATL 479. Some of my favorite crafts: PSM, ProTools playback mixer, Multi-zone RF Design, Contest/Unscripted A1, Cinema Verite Sound Ninja, Cable Craftsman, Post-prod. Nerd, Car Stereo Wanabe
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  1. This is a problem with you causing your SRc to become overloaded with excessive energy from the wideband inputs. Wideband recievers by design rarely include very effective filtering, and your RF inputs need to account for that, a fact wideband manufacturers rarely educate their customers about, instead focusing on the obvious benefit of flexible tuning. The whip antennas you have been using with the units act as a bandpass with their inherent frequency response. So the door is open for interference with your SRc's, what has to happen then, is that the units will perform just fine under most circumstances, and when enough RF garbage is allowed to come into your SRc's, your threshold of performance shrinks, and at some point you can't perform basic operation with tolerable performance until you deal with the problems your receivers are struggling with. Two places this happens frequently with users of distribution equipment is A. letting stronger RF levels into the system using wideband antennas with wider passbands and antenna gain and B. Introducing wideband active stages to the system without any additional consideration. These two things are tag-teaming your SRc and your SRc is losing the fight. Intermodulation distortion products are included in the amplifiers output when ANY two frequencies mix in an amplifier system at any level, and this happens For EVERY frequency against every other frequency, from one end of the spectrum to the other. The LEVEL of these products can range from very very low, to very very high. 3rd order IMD products, which are the nasty ones, rise exponentially with rising amplitude of the input signal. There are two places this is manifests itself -- higher noise floor across the entire passband of the system, caused by the summation of all the cumulative intermodulation distortion noise of the entire passband of the system -- and secondly, from overload happening when very strong RF inputs within your passband create excessive IMD products within your system. The first problem is dealt with by filtering an input that is too wide and forcing your distribution amplifier to output distortion from unnecessary input energy. The second problem can be solved by level control (lower output, wider spacing from your TX antenna, attenuators to your RX inputs) or else by insuring your filters control the levels for you by designing a system that does not include the transmit frequency in the passband for your RF amplifier stage or your receiver inputs. The short term solution is get the SRc's out of the distribution device, or get rid of the TX on the same band, until you understand and can address the problems with your RF setup. You've not set the system up correctly for your application, and have added equipment in the way of your signal that buys you worse performance than the $10 whips you started with. (part of the blame should fall on manufacturers who sell these systems with little to no education on proper setup). To make the distribution amplifier and receivers you have produce any positive results for you or hell, just to perform on par, make the TX energy exist OUTSIDE the passband of your distribution amplifier -- filtering is required after the antennas and before the distribution amplifier.
  2. What area are you working in? On the theory of controlling for RF overload: Many in Atlanta have found the current UHF spectrum to be FAR more energy-dense than several years ago. Some early wide-band designs like the SRc are notorious for being a bit tippy around overload thresholds, and your RF chain is being served by two active stages before the SRc. If either of these is being exposed to enough RF to begin building up distortion energy in the chain, it can become a compounding problem, once energy gets to the non-linear point. Distortion products of intermodulation rise 3dB for every 1dB of signal rise, but in most cases, the levels of intermod distortion fall below our noise floor, and go unnoticed. At high amplitudes nearing the IP3 of any stage (active antennas, distribution amplifiers, receiver front ends), though, distortion products can quickly transition from negligible to interfering, to unworkable. Better designed, higher quality active stages in manufacturers' designs, and better controlled signal paths in our systems play a large part in how robust our systems are to common (and uncommon) levels of RF energy. I took a Venue VRT system outside once and was amazed how much attenuation I could apply at our Wisycomm Antenna controller before the Venue would have less max range. -18dB or more. The sensitivity of our receivers is rarely the weakest link. If your RF path is high quality, and you're not in the middle of nowhere, too little overall energy has a FAR lower chance of giving your RF chain problems than too much energy, SNR being equal. First, make sure your distro amp and antennas and cables aren't somehow bad, and swap out some known good or brand new parts, and try your receivers out of the distro with just the antennas. Then, try attenuation of your system at max attenuation, and take your signals to the max range before dropout. Raise the gain of your system, and note whatever happens to the max range. Best if you do this in a known spot that's given you trouble before. Are your antenna patterns exposed to any nearby RF from your own sends, or digital equipment? Make space and note if there's any significant difference. Try with RX and TX but your recording system off. Perhaps bad wiring or bad power setup is a source of RF woes. RF explorer is a good way to move an antenna around your system and identify RF troublemakers.
  3. I bought the SoundKing DM20 board as an intermediate board to get the cart going on 12V before installing a full AC/DC/Inverter system and board later on. This board will transition to be a playback or backup system. I also ordered the StudioMaster Digilive board but returned it. The buttons have a clicky sound that is unacceptable for our work. DM20 consumes as much power as my Nomad. Two L7S NP batts will be fine for a day of operation. The eight XLR outs may be used on any of the 12 aux bus channels (1-4 mono and 5-8 stereo, you can use 5-8 as 2 channels of bussing), so you have plenty of routing flexibility for ISO prefade sends. The AES 1/2 mains Output may also be routed, so I use channel 1 for mix and channel 2 for boom ISO, giving 9 ISO channels plus mix to my Nomad. Less than 2ms latency claimed, I have not tested this yet. Additionally, the only mic preamp I use is the Nomad's Neverclip preamp, and route an output to the board. All other sources are line level to the board. Self-noise of the inputs is low. I haven't been able to hear any crosstalk when testing. Board withstands all my radio mics and Zaxnet blasting directly beside the unit. Sound quality is good, I would say above average for this tier of product, but you will notice on a Nomad or 788T that you get what you pay for. The high end recorders and mixers we use sound better. This sounds good enough, but don't expect best sound from this unit. I would expect support to be non-existent. Your support system is a backup solution. This would be an EXCELLENT playback board as the routing flexibility is very high. The fader caps should be replaced, they are too shallow. The startup time is like 30s or so. Touchscreen navigation is decent and responds quick enough for our work.
  4. THSnoddgrass, I also had the issue of Zaxnet whine on my M-216 transmitter. Switching to the BST-75 216 in my bag, with balanced input has eliminated the whine for me with my Nomad 12 Zaxnet transmitter. On the M-216 you could start hearing the whine with Zaxnet power set to 4 or 5 (of 7), I believe Nomad uses a 50mw transmitter.
  5. Here's the deal with Zaxcom in my experience. You have to buy in for the features and commit to repairs, quirks, software flukes and the like. These are not very commonplace in my experience, but they do crop up and you have to deal with it. Just like many other pieces of kit available to us. All of our equipment is expensive, and some work better than others. It's just the name of the game. With Zaxcom I've had a fair amount of parts fail over the course of a year of use but also would not consider the repair costs out of line with this business. Stuff happens and then poof you just spent $400 getting your kit back to where it was yesterday and it's down for a week or two on shipping. It happens. So the best thing IMO is to plan that you'll need to pay out from time to time to keep even straight from the factory Zaxcom equipment in spec. So, if you can commit to buying equipment from a specialty, low volume manufacturer, then you have to decide if the hassle and cost of maintenance is worth it or not. If you want something extremely reliable that will work well and never let you down, then I'd go with the options most of the mixers in your area are using. It will be easier to get replacements when stuff goes down, it's easier for others to use your kit. When you go Zaxcom you're in a smaller community supported by a smaller company. It's just more expensive. You're paying more than the MSRP.
  6. What is predelay? You can delay analog channels (but not digital, I think) on Nomad this is what I've been doing for years with my wireless. Would a timecode stamp shift in fractions of a frame be sufficient to have your mix be "real time" in relation to your delayed boom track?
  7. Hearing loss is typically most prominent and most irritating / painful at the higher frequencies. Higher frequencies tend to get damaged faster, hence why the dBA scale is chosen for measuring SPL for regulating exposure levels. There doesn't seem to be as much information out there regarding low frequency hearing loss related to low frequency exposure. The damage is less noticable even when it has happened because higher frequency harmonics usually exist so with low frequency loss, the brain can use harmonics to discern and understand the missing low frequencies (see audio plugins like Waves MaxxBass that add harmonics to increase the perception of bass even in speakers that can't physically produce the lowest frequencies). So, less is known about low frequency hearing loss, it's harder to detect when loss has occurred, and our measurement for regulation purposes uses a scale that is not very responsive to bass, so clubs can pump far more bass without overloading the regulating instrument (if any is being used at all!) Probably means we should tread with a bit more caution. Also, I don't imagine proper measurement is being used in many clubs or if it is, it's being circumvented. The sound levels at a Bassnectar show I attended were unbearable. Even with earplugs, the mids and highs left my ears severely ringing and I know just from my time calibrating safe monitoring levels for post, they were far above what I'm familiar with as a safe level. Indoor clubs and venues are an even bigger concern. Sound levels aren't an even spread across the room. High frequencies find resonances on wall materials, the ceiling, etc. Bodies block high frequencies pretty well, so a measurement in one spot in the room could be totally different from another. Low frequencies create massive nulls and peaks throughout the room and listeners in the back row by the wall or corner might be getting pummeled with bass that's not present at the mixing or measurement position. Stay safe, and if it's a health concern, stay away, if possible. Excessive SPL exposure is a big concern of mine. I wish the industry would get serious about regulation. It's way out of hand and modern soundsystems are so incredibly capable, especially at the huge EDM/rap festivals that are all the rage these days. http://www.sciencemag.org/news/2014/09/sounds-you-cant-hear-can-still-hurt-your-ears
  8. I love the additional RF outputs, compared to my Micplexer II, though I will say the RF metering on the MP2 is an absolute great feature. Even if the RF isn't showing at the receiver, it let's you know what your antennas and distribution amp are getting. Regarding (any brand) filters on your RF distro - it's such a huge help especially when using VHF for your transmitters to camera alongside dipole antennas. The MP2 is steep enough to help out when your camera wireless are only 30-50mhz away from your talent wireless. The Micplexer 2 metering gives me a great sense of placement for my camera wireless transmitter in the bag. Both units need a pass-through RF with wideband filtering. It is very very difficult to set up a filtered RF distro solution if your wireless are not ALL within 35mhz or ALL are wideband. Many of us have various blocks and would still like to filter the majority of them without losing the rest or creating a hodgepodge RF scheme with splitters, and extra single filters like Lectrosonics PF25 and PF50.
  9. Here are my initial impressions Since using this and the OR10 smaller wheeled case, I'll say build quality is good, mostly. One of the looped main zipper pulls has already broken and the plastic runners for pulling it onto curbs is scuffed pretty good. The inserts are more floppy than they should be and the soft walls won't grab them to hold a ton of weight, but for general use this is not an issue for me. I do think I will build out a proper, rigid mini cart with full rack system when I pursue more bigtime film stuff but for small budget film stuff it works great and looks professional on set. For any day playing on interviews and other stuff it is a godsend and is absolutely perfect. For reality run-n-gun stuff, it's too big if you're a one man army and is probably bigger than you'd want to work out of the back of a Town and Country anyhow. Orca makes several great medium and smaller rolling bags, so it's really a matter of how big your setup needs to be. The telescoping handle is rigid enough, the wheels are great, it is fairly balanced for going over uneven bumps without tipping sideways.
  10. My understanding is that the packs transmit at 32khz (roughly to 16khz audio). If you want an idea of how this sounds, try taking your current wireless system into a DAW and roll off at 16khz. From a post sound guy - for voice recording, you will never hear it. For classical music recording, well, shucks why are you going wireless? The files you record will be in whatever sample rate you set, with the super duper high frequencies not present. You won't miss them except on the forums.
  11. Glenn, is this (interference resistance) for the same reasons you're able to achieve better range and obstacle penetration?
  12. Microsoft Surface 3 is a great small tablet and Surface Pro 3 or 4 if you want larger. I would absolutely not recommend an AMOLED display like the Samsung Windows Tablets use for stuff like Touch that show similar graphics for long periods. I've been through about 4-5 phones with Samsung AMOLED panels and all of them show burn in after a year to year and a half. LCD tech for sure on the Nomad Touch.
  13. I had this exact thing happen two days ago on version 9-16. Downloaded the latest firmware and put the card in holding up and down on the TRX on boot fixed it. First boot hung with the number on screen. I think I didn't set up the SD card exactly according to the instructions the first time. Howey from support@zaxcom.com also emailed me additional files for recovery but I didn't need them. Email me at rscottbeatty@gmail.com and I'll send you his email and associated files.
  14. From my second-hand (or third-hand) knowledge, I have heard that Arri has commissioned the 5 pin small connectors from Lemo and Arri sells the connectors and associated cables, likely for an exorbitant amount. Take that for what you will, I have no guarantee this is accurate. Most problems with the Lemo connectors are due to difficulty wiring them. They are VERY easy to wire poorly due to their size. I can't imagine 5 pins in one of those connectors. I want to die a little every time I wire a Lemo 3. Reach out to me if you're wiring the 3 pins. I have some tips that can help you get them wired and protect them from shorting against other pins and the metal casing that's about 1/2mm away from the pin wells.
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