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Author Topic: Mixing Mics with Picture Sound Martin McCaffery Film God Posts: 2481 From: Montgomery, AL Registered: Jun 99 posted 05-01-2019 01:51 PM                        We're interested in getting a traveling show where the host talks over cheesy movie clips. We have a CP650 for films and a Shure mixer for our microphones. They have a Playstation 3 for their DVD clip reel. It has HDMI and RCA sound outputs. Currently, the mics go from the mixer to the 650 and out the surround speakers. They are a separate button, so can't talk over the picture. HDMI goes through an OPPO, and then splits into sound and picture. I don't think stereo is going to be a major concern here. Ideally I'd like the picture sound to come out of Center and the mics in the surrounds. Is there a way to do this within the 650? Or should I just use the Shure mixer and plug the PS3 into AUX and put everything through Center? Will this be unbearable? Or just borrow a PA?  |  IP: Logged Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 05-01-2019 02:03 PM                        How are you getting from the mixer to the CP650? Does it have a mic or line output? You could do mic+Playstation to mixer to the CP650 non-sync inputs, and use format 75. This would require a line-level output from the mixer. If your Shure can't do this, you could rent/borrow something like a Mackie 1202 (or equivalent) that would. If you want the mics in the surrounds, you would need to do something clever like invert the phase of each microphone and put that into a separate input channel on the mixer. An XLR Y-cable (one XLR-F to two XLR-M, with pins 2 and 3 flipped on one of the M connectors) between each mic and two mixer channels would work if you don't need phantom power. In that way, you would have two mixer channels for each mic, and would need to keep the levels on each identical to force the Dolby decoder to steer the output into the surround channel. Another option would be to use the external 6-channel input, though you would probably need to make or modify a cable for that. This is an example of where a custom format on a CP500 would make this really easy to do. The same is probably true of the AP20. No doubt someone will be along with an explanation of how to do this in Q-sys with two mouse clicks.  |  IP: Logged Carsten Kurz Film God Posts: 4340 From: Cologne, NRW, Germany Registered: Aug 2009 posted 05-01-2019 03:44 PM                     There are many ways to do this - but, honestly, the easiest and safest is to buy or borrow a mobile speaker cart. There are some systems operating from a battery and include a wireless mic receiver. This is by far the easiest way to do it, just bring it into the auditorium and start talking. You can also use it in a lobby, on a parking lot, etc. You can buy these in decent quality from 150US$ up. https://www.bhphotovideo.com/c/search?setNs=p_PRICE_2%7c0&Ns=p_PRICE_2%7c0&sortType=default&ci=13466&srtclk=sort&N=3992 462029 Many local music stores have simpler mains powered active monitor speakers featuring a mic input available. Some cinema processor offer that option, but on the AP20/25, it is limited in at least two ways - live mic delay, and available sources/presets that allow a Mic to be added. You could mix DVD and mic externally, but then your options to route content and mic audio to different speakers are zero. Also, you would want a solution without having to mess with the current cinema audio system wiring or setup. Therefore, get a mobile active speaker, and be done with it. That said, I don't think sending everything to center would be unbearable. Wether you want the mic coming from surrounds or center depends a bit on where the speaker will be located. I usually prefer the sound from a speaker person to come from his direction. - Carsten  |  IP: Logged Jim Cassedy Phenomenal Film Handler Posts: 1661 From: San Francisco, CA Registered: Dec 2006 posted 05-01-2019 04:01 PM                     I had to do something like this a couple of years ago. The program, which had a number of sound & silent film clips was running on a Macbook Pro. All of the clips were 2/ch - stereo or mono, and the presenter wanted the ability to comment over the screen audio. Like you, I also wanted to have the "Film Clip Audio" come from the screen, but have the 'live" microphone audio come from the surrounds. Because we had a tight turn-around between this show and the one after it, I also needed to come up with a way of doing this that didn't involve making a lot of changes or adjustments to the existing audio system. Here's what I wound up doing: "PICTURE AUDIO": 1) The 2ch output of the computer was fed into one of the CP-650's "Non-Sync" inputs, using a 1/8in to RCA Cable. I used the standard "Non Sync" setting (no Pro-Logic, etc decoding) 2) The microphone audio (single mic) went to a small Mackie mixer. The mixer was capable of 2ch output, so I simply centered the pan-pot on the mic channel to get 2 mono outputs from the mixer. GETTING AUDIO TO THE SURROUNDS: The surround amps in this theater were QSC 1400 or 1700's, which had balanced XLR inputs on the back. However several brands of amps have multiple input options (XLR, Bal & Unbal 1/4in jacks, plus screw &/or other terminals)on them. So, I simply ran 2 XLR cables from the mixer output into the XLR inputs on the back of the left & right QSC surround amps. At first I thought I might have to disconnect the screw terminal inputs from the CP-650 audio to avoid some signal 'back-feeding' to the 650 and winding up in the screen channels, but I found this not necessary. The advantage of this was that it required no actual re-wiring or putzing around with the existing wiring or level settings, as the mic levels were all adjusted at the mixer, and all that was necessary to put things back to normal for the next show was to pull the XLR's, & re-plug the normal non-sync pre-show music source back into the CP-650. As I already had a small Mackie mixer & the necessary audio cables, etc in my "bag of tricks", I didn't have to go out & buy or borrow any additional equipment. The quick & easy set-up & break down meant I actually even had time to take a break before the next show!  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-01-2019 04:04 PM                     What we have done for sites that want that functionality is to put a DSP box on the surrounds and mix the mics with the normal surround feeds and provide for a mic-defeat. It has worked rather well. Of course, if you don't have such a box, it will cost money but Extron has a low-cost box in the DMP 44 LC. Naturally, you could do it with just a mixer on the Ls/Rs channels too but with a bit of a DSP you can provide EQ at that stage.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 05-01-2019 06:40 PM                     Yes, for sure put the voice in the surrounds. Not only is it heard clear as a bell but you won't have any feedback because of the normal delay.  |  IP: Logged Randy Stankey Film God Posts: 6539 From: Erie, Pennsylvania Registered: Jun 99 posted 05-01-2019 07:55 PM                     Several years ago, I was working on a stage play where, in one scene, the lead woman character had to pour a cup of tea from a boiling kettle on a certain cue. We went through all sorts of ideas... Dry ice and warm water -- But the steam sinks and looks weird. Liquid nitrogen -- Same thing but even more unpredictable. Sound effects -- But the sound crew has to play SFX of a kettle boiling and whistling on cue. Finally, somebody spoke up and said, "Why don't you just BOIL THE WATER?" Get an electric hot plate and a kettle. Put just enough water in the kettle so that it boils at the right time. It was simple and it worked! Instead of going through all the machinations to have a microphone for a one-off gig, why don't you just boil the water? Borrow or rent a portable sound system for the gig. It'll be easier and less fuss. It's sure to work on-time, every time. Just boil the water!  |  IP: Logged Martin McCaffery Film God Posts: 2481 From: Montgomery, AL Registered: Jun 99 posted 05-01-2019 08:25 PM                        Yeah, boiling the water seems the easiest thing, though if this works out we may have more of them, so it would be nice to have an easy, cheap, hack.  |  IP: Logged Randy Stankey Film God Posts: 6539 From: Erie, Pennsylvania Registered: Jun 99 posted 05-01-2019 09:00 PM                     You know the saying... "You can have it GOOD, FAST or CHEAP... You are allowed to pick two out of three."  |  IP: Logged

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