my profile | my password | search | faq & rules | forum home

» Film-Tech Forum ARCHIVE   » Operations   » Film Handlers' Forum   » external fader for non-sync on CP50 (Page 1)

This topic comprises 2 pages: 1  2

Author Topic: external fader for non-sync on CP50 Jeff Else Expert Film Handler Posts: 125 From: Detroit, MI, USA Registered: Nov 2006 posted 03-02-2010 10:44 PM                     how would one go about adding a more robust external fader to control non-sync level on a CP50? i have a film festival coming up with mostly local, DVD based stuff. The levels with such things tend to be all over the place and its annoying using a tweaker. I would love to have the fabled Cat 223 daughterboard but it seems there are none to be found...  |  IP: Logged Jean-Marc Toussaint Film Handler Posts: 60 From: Paris, France Registered: May 2008 posted 03-03-2010 02:37 AM                        Why not trying a small DJ mixing console? If this is temporary, for the duration of your festival, it should do the job. I have rerouted the NS1 input on my CP to the front of the sound cabinet, adding RCA connector so I can basically hook any kind of audio, from tape player to super 8 projector...  |  IP: Logged Jim Cassedy Phenomenal Film Handler Posts: 1661 From: San Francisco, CA Registered: Dec 2006 posted 03-04-2010 12:02 AM                     Another soloution is the simple circuit below. I've got one of these on the input of a mono sound system at at theater to control the level of the pre-show CD player and give the capability to fade the music up & down. I beleive I used a 100kOhm "audio taper" potentiometer which I got at Radio Shack. If you need to control a stereo source you'll need to get a dual "stereo"(ganged) pot and connect each channel as you see here: You can build one of these for less than $10.00 I even have a "portable" version I built using a couple of RCA audio cables and an empty band-aid box. (The metal box provides shielding & a place to mount the volume control)  |  IP: Logged Cameron Glendinning Jedi Master Film Handler Posts: 845 From: West Ryde, Sydney, NSW Australia Registered: Dec 2005 posted 03-04-2010 12:32 AM                     I've built and used Jims style of box and recommend it! works well and does a first class job. I got my bits from Jaycar.  |  IP: Logged Ian Parfrey Phenomenal Film Handler Posts: 1049 From: Imbil Australia 26 deg 27' 42.66" S 152 deg 42' 23.40" E Registered: Feb 2009 posted 03-04-2010 01:22 AM                     I'm guessing the "audio taper" is a log pot as opposed to a linear?  |  IP: Logged Jeff Else Expert Film Handler Posts: 125 From: Detroit, MI, USA Registered: Nov 2006 posted 03-04-2010 02:15 AM                     i like jim's idea, but i would like it to control all four input channels. could i remove the trimpot on the 113c and solder wires to an external potentiometer? if i did this, what type of potentiometer would i use?  |  IP: Logged Jim Cassedy Phenomenal Film Handler Posts: 1661 From: San Francisco, CA Registered: Dec 2006 posted 03-04-2010 10:53 AM                     Well, of course you can do anything you want, but that doesn't necessarily mean it's a good idea. If you want to control more than one source, than I'd try to find a small mixer, like Jean-Marc suggested in the first reply. A couple of years ago, I bought a small 4-Channel mixer from NADY systems. You Can See One Here You can set it up for either mono or stereo ins & outs. Inputs are unbalanced. Output can be balanced or unbalanced. All connections are via 1/4in plugs & jacks, so I bought some cables & adapters. (Since I HATE having adapters hanging directly off of the back of pieces of equipment) This thing works great! Radio Shack used to sell a similar unit. I'm not sure if they still do. I also have a trusty old SURE M-267 mixer I got cheap on e-bay. Which mixer I use depends on the needs of the partciular show I'm doing. Yes, all this stuff cost me a little out-of-pocket cash, but it makes it so much easier for me to do a professional job.  |  IP: Logged Tony Bandiera Jr Film God Posts: 3067 From: Moreland Idaho Registered: Apr 2004 posted 03-04-2010 11:17 PM                     Jim's trim pot idea is the simplest, most cost-effective and will work very well. Another good accessory to have on hand is a ground-loop isolator or a pair of "direct boxes" to help prevent any hum issues.  |  IP: Logged Jeff Else Expert Film Handler Posts: 125 From: Detroit, MI, USA Registered: Nov 2006 posted 03-05-2010 02:32 AM                     i need it to control all four input channels, so the mixer would need to have four outputs... at this point i'm looking at a costlier mixer, and it would be easier operationally to have everything on one control. if one were to remove the nonsync level trimpot and solder wires to an external potentiometer, what type would be used? what kind of trouble am i getting myself into?  |  IP: Logged Sean McKinnon Phenomenal Film Handler Posts: 1712 From: Peabody Massachusetts Registered: Sep 2000 posted 03-05-2010 09:54 AM                        Why do you need to control the levels for all 4 channels? You should be able to take LT and RT right out of the dvd player thru the mixer and into the non-sync input?  |  IP: Logged Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 03-05-2010 10:18 AM                        He must have an external box that decodes the L/C/R/S signals from the DVD. Two thoughts: - you can use a 4-gang pot to control the gain of all four unbalanced channels - you will get better sound quality out of non-sync on the CP50 by using the cat. 112 manual switch card rather than the 113C automation card; the manual card connects the NS inputs directly to the amps, so you will need an external gain control  |  IP: Logged Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 03-05-2010 11:32 AM                        Unless the DVD player decodes internally and outputs 6.1 in which case he still needs a multiple gang pot or small mixer.  |  IP: Logged Jeff Else Expert Film Handler Posts: 125 From: Detroit, MI, USA Registered: Nov 2006 posted 03-06-2010 02:11 AM                     i have a bluray/DVD player with RCA outs for all 6 channels. a 4 gang pot sounds like the way to go. good to know about the 112, i do happen to have one kicking around. how does the 113c affect the NS sound?  |  IP: Logged Marin Zorica Jedi Master Film Handler Posts: 671 From: Biograd na Moru, Croatia Registered: May 2003 posted 03-08-2010 05:54 PM                     Jeff, if you have 113C than is easy, because 113C uses TDA ic which regulates 4ch input level, so remove non sync level trimmer which is on 113 board near MONO switch and put it somewhere outside, as CP50 don't have front panel fader I did added it one time, also did use stereo pot, so one side is for main fader, other for non-sync (instead that trimmer) so with one know I do control all levels....  |  IP: Logged Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 03-08-2010 05:55 PM                        The cat. 112 gives you a direct path to the amps. The 113C has some electronics on it (the aforementioned gain pot) that will degrade sound quality.  |  IP: Logged

All times are Central (GMT -6:00)

This topic comprises 2 pages: 1  2

Printer-friendly view of this topic

Hop To: Select a Forum: Category: Operations -------------------- Digital Cinema Forum Film Handlers' Forum Large Format Forum Ground Level Feature Info, Trailer Attachments & REAL Credit Offsets Category: Community -------------------- Film-Yak Film Handlers' Movie Reviews The Afterlife Bob Maar's Joke-A-Thon Category: Classified -------------------- Equipment and Supplies Wanted/For Sale Help Wanted/Seeking Employment Category: System -------------------- Software Beta Testing Forum

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.