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Title: Multi-channel transmission over long distances
Post by: Carlos del Valle on July 21, 2011, 06:04:15 PM
Hello all

I have an event coming where I need to send 12ch of audio over 350 meters. I have doubts on wich is the best way to do this. My best guess is Ethersound, with switches to "reamplify" the signal every 100m.

Is there any other method of transmitting multichannel audio over long distances, without reamplification? Is there a ethersound over fiber optic protocol (optocore)? I recall reading something about it somewhere but I can't find it now...

Thanks,

C.
Title: Re: Multi-channel transmission over long distances
Post by: TJ (Tom) Cornish on July 21, 2011, 06:19:55 PM
Hello all

I have an event coming where I need to send 12ch of audio over 350 meters. I have doubts on wich is the best way to do this. My best guess is Ethersound, with switches to "reamplify" the signal every 100m.

Is there any other method of transmitting multichannel audio over long distances, without reamplification? Is there a ethersound over fiber optic protocol (optocore)? I recall reading something about it somewhere but I can't find it now...

Thanks,

C.

Analog isn't a problem. I'm working on an outdoor install and we have run 6-pair Aquaseal cable all around the property, and one run is 750m. With isolation transformers it's working great.
Title: Re: Multi-channel transmission over long distances
Post by: Mac Kerr on July 21, 2011, 09:37:38 PM
I have an event coming where I need to send 12ch of audio over 350 meters. I have doubts on wich is the best way to do this. My best guess is Ethersound, with switches to "reamplify" the signal every 100m.

Is there any other method of transmitting multichannel audio over long distances, without reamplification? Is there a ethersound over fiber optic protocol (optocore)? I recall reading something about it somewhere but I can't find it now...

I have run analog audio as much as 3000' over standard multipair cable. I might hesitate to run mic level that distance, but with any digital system you are going to have to have a preamp before the transmission system anyway, I'd stick with analog multicable unless I was just looking for an excuse to buy an expensive digital multi like Rocknet (http://www.riedel.net/AudioSolutions/RockNetOverview/AboutRockNet/tabid/502/language/en-US/Default.aspx) or Optocore (http://www.optocore.com/).

Mac
Title: Re: Multi-channel transmission over long distances
Post by: Mark Oakley on July 21, 2011, 11:51:05 PM
I too have run analog line-level signals 1000 ft. (with iso transformers at the recieving end). Dead quiet; not a hint of noise.

-Mark
Title: Re: Multi-channel transmission over long distances
Post by: Tim McCulloch on July 22, 2011, 02:47:50 AM
I have run analog audio as much as 3000' over standard multipair cable. I might hesitate to run mic level that distance, but with any digital system you are going to have to have a preamp before the transmission system anyway, I'd stick with analog multicable unless I was just looking for an excuse to buy an expensive digital multi like Rocknet (http://www.riedel.net/AudioSolutions/RockNetOverview/AboutRockNet/tabid/502/language/en-US/Default.aspx) or Optocore (http://www.optocore.com/).

Mac

Hi Mac-

The Study Hall used to have an article by Chuck McGregor on "Driving Really Looooong Lines."  Is there a way for us to get some of these "legacy" article back into the SH?
Title: Re: Multi-channel transmission over long distances
Post by: Carlos del Valle on July 22, 2011, 04:20:04 AM
My main concern is running 12 channel multipair 350m. Buying a snake that long would be expensive, and connecting 4 100m runs would be too much interconnection in between. I was looking for a digital solution because it's only one cable, and I can make redundancy...
Title: Re: Multi-channel transmission over long distances
Post by: Mac Kerr on July 22, 2011, 08:39:00 AM
My main concern is running 12 channel multipair 350m. Buying a snake that long would be expensive, and connecting 4 100m runs would be too much interconnection in between. I was looking for a digital solution because it's only one cable, and I can make redundancy...

Is this a permanent install? A gig you will do again and again? If not, rent the multi. Four 250' 15pr trunks should be no big deal at the shops I deal with, and good quality multipin connections do not degrade the signal.

If it is permanent, buy a 1000' spool and install it. If it is a repeating gig, the 12pr will be a little cheaper than digital, but digital will be easier to load in/out. You will have to make the call on how you want to spend your money. The 2 systems I linked to previously would be my recommendation, or maybe a Stagetec Nexus (http://www.stagetec.com/web/en/audio-technology-products/digital-audio-routing/nexus-star.html).

Mac
Title: Re: Multi-channel transmission over long distances
Post by: TJ (Tom) Cornish on July 22, 2011, 08:41:57 AM
My main concern is running 12 channel multipair 350m. Buying a snake that long would be expensive, and connecting 4 100m runs would be too much interconnection in between. I was looking for a digital solution because it's only one cable, and I can make redundancy...


In my opinion, digital interconnections every 100m are more problematic than analog ones - using a bunch of cheap ethernet switches as repeaters is not going to be a better solution, which leaves fiber.  Fiber is fragile, expensive, and requires media converters and/or expensive boxes on both ends.  It can work, but how are you protecting it?  Is this an indoor event where you can fly the cable, or is this outside in the mud being driven over by golf carts all day?

If you're buying all this, no matter what way you slice it, analog will be cheaper, and probably more reliable.  You can buy the wire and jacks to build your own 1000' 12-channel snake for between $1000 - $2000 depending on what wire you use.  You may be able to rent something digital cheaper, but I doubt it.
Title: Re: Multi-channel transmission over long distances
Post by: Tim McCulloch on July 22, 2011, 01:19:37 PM
Hello all

I have an event coming where I need to send 12ch of audio over 350 meters. I have doubts on wich is the best way to do this. My best guess is Ethersound, with switches to "reamplify" the signal every 100m.

Is there any other method of transmitting multichannel audio over long distances, without reamplification? Is there a ethersound over fiber optic protocol (optocore)? I recall reading something about it somewhere but I can't find it now...

Thanks,

C.

If you go Ethersound, there are a number of industrial-strength RF solutions for packet data transmission.  How much end to end latency is tolerable?

Also, is this a "solid" 350m run, i.e. there are no taps along the run for signal distribution?
Title: Re: Multi-channel transmission over long distances
Post by: Jens Palm Bacher on July 22, 2011, 02:33:39 PM
Hello all

I have an event coming where I need to send 12ch of audio over 350 meters. I have doubts on wich is the best way to do this. My best guess is Ethersound, with switches to "reamplify" the signal every 100m.

Is there any other method of transmitting multichannel audio over long distances, without reamplification? Is there a ethersound over fiber optic protocol (optocore)? I recall reading something about it somewhere but I can't find it now...

Thanks,

C.
350m of analog line level is not a problem. Just throw a transformer on the receiving end.
If you insist on fibre, a cheap possible solution would be a AVIOM setup with a pair of http://www.lightviper.com/LV%20Series%2032/lvseries32ef2.html
Title: Re: Multi-channel transmission over long distances
Post by: Oliver Driver on July 22, 2011, 03:25:04 PM
Hello all

I have an event coming where I need to send 12ch of audio over 350 meters. I have doubts on wich is the best way to do this. My best guess is Ethersound, with switches to "reamplify" the signal every 100m.

Is there any other method of transmitting multichannel audio over long distances, without reamplification? Is there a ethersound over fiber optic protocol (optocore)? I recall reading something about it somewhere but I can't find it now...

Thanks,

C.


We regularly use Ethersound over 300m to 500m distances over fibre - we use the Allied Telesyn MC102XL ( http://www.alliedtelesis.com/p-2219.html ) converters from CAT5 to Fibre ( as recommended by Ethersound ) and have had no problems. It's much easier than using CAT5 and hubs every 100m ( also means you don't loose the bi-directional element of Ethersound ). They cost around $100 each and have been very reliable over the last 2-3 years, with no failures or problems.

As it's Ethersound you also get the full channel count (64) in both directions which is useful for talkback or spares.

Hope this helps.

Oliver.



Title: Re: Multi-channel transmission over long distances
Post by: Iain.Macdonald on July 22, 2011, 03:36:10 PM
Hello all

I have an event coming where I need to send 12ch of audio over 350 meters. I have doubts on wich is the best way to do this. My best guess is Ethersound, with switches to "reamplify" the signal every 100m.

Is there any other method of transmitting multichannel audio over long distances, without reamplification? Is there a ethersound over fiber optic protocol (optocore)? I recall reading something about it somewhere but I can't find it now...

Thanks,

C.

Carlos,

As others have said, running that much analogue is usually ok. With the proviso that you use decent screened multi. Also that your equipment at each end, is designed properly, and it doesn't have pin 1 problems etc.

For a low-ish cost, but otherwise high quality digital solution. You could check out the Roland REAC system. A couple of 1608 boxes and a couple of S-Opt boxes plus fibre cable would be very economical, and more importantly it would give you a 2km range. If you are considering going digital for the rest of your system, I would suggest looking at their bigger systems. In the UK our national broadcaster (BBC) and many independent broadcast facility providers are using the REAC system. I think that Ethersound appears to be dead in the water, except for those who already have some equipment that uses it.

Iain.
Title: Re: Multi-channel transmission over long distances
Post by: Carlos del Valle on July 24, 2011, 08:40:43 AM
Thanks for all the awnsers. The run is for a press send in a large corporate event, and the cable would be hidden and not abused. I thought of Ethersound because it's only one cable, and I figured it would be a cheaper solution than a 300m analog multipair.

I liked Olivier's solution, I'll look into it, and if my boss is not into buying it, I guess I'll run analog lines anyway... But with Ethersound I would be able to use a send from my SD7, to a LS9 to control all media feeds using just one not so expensive cable...

Thanks all.

Title: Re: Multi-channel transmission over long distances
Post by: Tim McCulloch on July 24, 2011, 10:44:42 AM
Thanks for all the awnsers. The run is for a press send in a large corporate event, and the cable would be hidden and not abused. I thought of Ethersound because it's only one cable, and I figured it would be a cheaper solution than a 300m analog multipair.

I liked Olivier's solution, I'll look into it, and if my boss is not into buying it, I guess I'll run analog lines anyway... But with Ethersound I would be able to use a send from my SD7, to a LS9 to control all media feeds using just one not so expensive cable...

Thanks all.

The price of the copper should be the least of your concerns.  The price of adding network switches (not consumer products, but enterprise-level) to a robust and redundant run of CAT5e will probably equal the cost of multipair analog.  That's what we've been trying to tell you, Carlos... and that analog will not present signal degradation of any significance.

I'd just rent the cable run and get 16 pairs so you have a couple of backup lines and room for party line intercom as well.

Have fun, good luck.

Tim Mc
Title: Re: Multi-channel transmission over long distances
Post by: Mac Kerr on July 24, 2011, 10:53:46 AM
Thanks for all the awnsers. The run is for a press send in a large corporate event, and the cable would be hidden and not abused. I thought of Ethersound because it's only one cable, and I figured it would be a cheaper solution than a 300m analog multipair.

I liked Olivier's solution, I'll look into it, and if my boss is not into buying it, I guess I'll run analog lines anyway... But with Ethersound I would be able to use a send from my SD7, to a LS9 to control all media feeds using just one not so expensive cable...

Are there really 12 different audio feeds for press? Even at the biggest press focussed event I do we only have 5 different feeds, because we have 5 simultaneous venues. Each of those 5 feeds goes to a 32 output press DA in the workroom. What are your 12 feeds?

Ethersound would be a viable solution, if there was an Ethersound card for the SD7, I don't think there is, and to get 12 channels you would need 2 8ch cards for the SD7. You would only need 1 16ch card in the LS9.

Mac
Title: Re: Multi-channel transmission over long distances
Post by: Iain.Macdonald on July 24, 2011, 11:09:20 AM
Are there really 12 different audio feeds for press? Even at the biggest press focussed event I do we only have 5 different feeds, because we have 5 simultaneous venues. Each of those 5 feeds goes to a 32 output press DA in the workroom. What are your 12 feeds?

Mac

Mac,

I know you hate wielding the big stick. But it's time to remind people, that providing some detailed information, when they post a question, is not just helpful, but good manners. The OP, now appears to only bear a passing resemblance, to the real requirement. I would add to your question, is it press or broadcast? That would change the equipment used.

Iain.
Title: Re: Multi-channel transmission over long distances
Post by: Jonathan Johnson on July 24, 2011, 12:29:58 PM
The price of adding network switches (not consumer products, but enterprise-level) to a robust and redundant run of CAT5e will probably equal the cost of multipair analog.

Don't forget that these switches will also require power, which may or may not be available at the location where the switches must be. So in addition to the costs already mentioned, you may have the cost of providing power; 100m of extension cord may not be as simple as it sounds. There are many questions that this adds: Will voltage drop be acceptable? (Always a consideration in long-distance power runs.) Will the power cable run next to the Ethernet cable? That may result in RFI/EMF that degrades the Ethernet signal. Is the power reliable? Will the local inspector have something to say about the installation?
Title: Re: Multi-channel transmission over long distances
Post by: Carlos del Valle on July 24, 2011, 05:45:52 PM
We have L-R, L-R backup, L-R voice, LR music, LR send to a pair of speakers, 2 spare lines. Total, 12 sends.

I didn't give much info because I didn't think it was relevant to the question, wich was about methods of sending multipair signals over long distances.... not my intention to be ill-mannered.

In all, I guess analog is the best way. thanks again!
Title: Re: Multi-channel transmission over long distances
Post by: Oliver Driver on July 25, 2011, 04:31:32 AM
Thanks for all the awnsers. The run is for a press send in a large corporate event, and the cable would be hidden and not abused. I thought of Ethersound because it's only one cable, and I figured it would be a cheaper solution than a 300m analog multipair.

I liked Olivier's solution, I'll look into it, and if my boss is not into buying it, I guess I'll run analog lines anyway... But with Ethersound I would be able to use a send from my SD7, to a LS9 to control all media feeds using just one not so expensive cable...

Thanks all.

Hi there,

Just a though....but if you're using an SD7 then maybe you could use a D-Rack with the fiber option?

Let me know if you need any advice or help on the Ethersound way of doing it.

If you want to use a more enterprise class solution for Ethersound then look at the HP ProCurve 2510-24 switch with the fiber gigabit modules and set up a VLAN ( Yamaha provide instructions for how to set this switch up which I can send you ) - it also enables you to do two neat tricks....one is that if you use two fiber modules in each switch you get an automatic back up ( glitch free when main fiber drops, not glitch free when the main fiber is restored ) and also you can use the other 9/10th's of the fiber for data - again all explained in the Yamaha info.

Cheers,

Oliver.
Title: Re: Multi-channel transmission over long distances
Post by: Iain.Macdonald on July 25, 2011, 01:02:35 PM
We have L-R, L-R backup, L-R voice, LR music, LR send to a pair of speakers, 2 spare lines. Total, 12 sends.

I didn't give much info because I didn't think it was relevant to the question, wich was about methods of sending multipair signals over long distances.... not my intention to be ill-mannered.

In all, I guess analog is the best way. thanks again!

Hi,

Ah! different reply required   ;)

I would forget EtherSound, unless you already have it. SD7 has spare MADI ports. Just use a MADI to Fibre converter, or a MADI to EtherSound converter, if you have the appropriate EtherSound box for the ouput end. Or else, if you own the SD7, invest, in the Digico optional fibre interface. The console has more than enough paths for the stems. The use of EtherSOund seems to have peaked, but MADI is still very popular, especially with broadcasters.

You didn't say what kind of press is at the receiving end. If it's broadcast, they might well be happier with MADI, though I don't know where you are located. One tip. It is generally thought best for analogue outputs for press, to have transformer isolated outputs. Journalists are notorious for shorting out, and introducing buzz in to these systems.

A few links. Lots more available.

http://www.rme-audio.de/en_products_madi_converter.php (http://www.rme-audio.de/en_products_madi_converter.php)

http://tinyurl.com/3svbyno (http://tinyurl.com/3svbyno) Sydec m-o & stage boxes

http://tinyurl.com/3dzexgp (http://tinyurl.com/3dzexgp) SSL

http://tinyurl.com/3udaty3 (http://tinyurl.com/3udaty3) SSL Madi stage box

Cheers.

Iain.
Title: Re: Multi-channel transmission over long distances
Post by: Andrew Hollis on July 27, 2011, 10:42:55 AM
I second MADI. There are many manufacturers (broadcast and pro audio) in this space making IO boxes that get you from MADI to AES, Analog, ADAT, etc. It's easy to do on a budget. One or two cables and you're done, up to 64 channels beyond 500m per link, platform agnostic, minimal setup, no configuring.

It looks like the DiGiCo SD7 has 4 MADI interfaces standard.