Linking Karaoke To Multiple Screens

[Slimboy Fat 0]

Hi All.

 

Now that we're pretty much settled into our new area I am now looking to fire up the rig and get gigging once again. I've scouted our new area and there does seem to be a healthy demand for DJ services - especially in one or two more specialised niches. The local karaoke scene is quite healthy and what with all of my gear sitting in the garage gathering dust, I have come to the decision that it would be extremely rude not to.

 

One question I was pondering just before the move and new job took over my life was how several Karaoke DJs I have seen link their equipment up to a venue's own multiple TV screens without any visible sign of extra cabling from the DJ rig? Is there some sort of gadget which patches in to the TV signal remotely or is it purely down to many metres of well-hidden cable?

 

Your advice will be greatly appreciated, thanks. Jase.

[vokf 0]

Robsta and the other Karaoke guys will know for sure, and I'm sure it varies by venue.

 

My local uses RF cable (ie aerial) for its screens. When I did some video djing for Halloweeen, I could patch using S-Video into the projector, but all other displays were RF only.

 

To get this working, I'd need an RF modulator with composite or S-Video in and RF out (ie TV Aerial type signal).

 

Its probably best to work this out on a venue by venue basis. Some may have decent wiring and you'll just have a Composite (RCA) type connector near the set-up area.

 

I did a 70/80s night a few years ago, and they had this.

 

Jason

[deejaymitch 0]

Any venue I've worked in that has multiple screens has them all linked up already, so you only need to plug into their main video output source (I'm probably wording this terribly), but it's really easy in these cases.

[superstardeejay 0]

Yes. Any venue where the screens have been installed correctly will use a Video Distribution Amplifier. This accepts 1 composite video input from your source (ie karaoke machine or Karaoke mixer) and amplifies it into multiple outputs for each screen. This is a lossless way to do it, just connecting video inputs in parallel leads to ghosting (signal reflections) and loss of contrast the more screens are added since composite video is a 75R system and the source needs to see a 75 ohm load...the impedance works the same way as speakers so each additional screen halves the impedance and doubles the load and thus reduces the available signal across the whole system.

 

The Video Distribution Amp will be located anywhere, from by the DJ box, to behind the bar or in a cupboard...so run your single cable to this. Be aware of leakage currents in multiple tv systems, this can build up and is not good if connected into your system using handheld wired mics etc. A good installation will have the video system earthed at the distribution amp to prevent microphones aquiring high voltages wrt earth.

Edited April 18, 2010 by superstardeejay

[gadget 0]

Be aware of leakage currents in multiple tv systems, this can build up and is not good if connected into your system using handheld wired mics etc. A good installation will have the video system earthed at the distribution amp to prevent microphones aquiring high voltages wrt earth.

 

Is that the tingling sensation that's felt on some pieces of equipment (with metal chassis)?

[Robster 0]

I have also seen video distribution to multiple flat screens and projectors via the PC input using powered VGA splitters/distribution boxes.

 

The bold type of superstardeejay's post is the most important Correctly so many installs in pubs are cobbled together from a bloke in the vault who used to be a leccys mate in 1964 or a telephone engineer 30 years ago etc etc

 

I carry a box of magic bits which has amongst other things

 

a rf modulator... lots of long cables of various connectors several s-video to composite bi directional converters , scart adaptors ...VGA to composite and s-video powered converters ..powered VGA splitters and a DigiSender X7 Wireless Video Sender and lots and lots of gaffer tape and safety tape etc there must be over £600 of bits and bobs in that box that gets me though most venues.

 

The video sender i use as a last resort and always trust proper cables well hidden ratherover using wireless

 

As with functions if i get asked to do a pub i have never done before i pop down and take a good look before the gig so i am good to go on the night.

Edited April 19, 2010 by Robster

[vokf 0]

so many installs in pubs are cobbled together from a bloke in the vault who used to be a leccys mate in 1964 or a telephone engineer 30 years ago etc etc

 

Sounds like the guy who wired up my local

 

The landlord has spashed out on some decent projectors and plasma TV's, but behind the bar is a mess of composite video/scart adapters and a SKY box...

He's due a refurb soon, so I hope the mess of cables are sorted. I've suggested an AV socket on the stage, to make Karaoke etc easier and possible on the big screens.

 

As there are about 4 Plasma screens and 2 projectors, and distribution amp would be a good choice, and give much better quality when we're watching the footie. No point in having a HD compatible projector if you're feeding it rubbish quality!

 

 

 

 

[banginbeats 0]

As a video DJ, most of the venues i work in only need one connection for the screens, by standard is a yellow rca (phono) i always take a converter to a scart with me just incase.

 

Its best to go in and double check with the venue first tho.

 

[superstardeejay 0]

Is that the tingling sensation that's felt on some pieces of equipment (with metal chassis)

 

Yes. If you can feel something, the voltage on it is too high to be safe. Put a digital multimeter on it to an earthed point and you'll be surprised and possibly dismayed.

 

Due to experience, the IEE regs now considers any voltage over 24V to be hazardous (it used to be over 50V but has been amended).