Cannot get broadcast stream going on version 4.5.0.715

[radiodungog]

Hello,

We are a community radio station in Australia and we are evaluating RadioBOSS prior to purchasing it.  We are down to the last few features that we need to sort out prior to going on air.  This last one is for our quest of minimal equipment.  Our audio link from studio to the transmitter is over a 3Km path using a local WiFi network.  It is a fantastic path and works perfectly.

We are using the broadcast streaming feature to do this.  Testing it in the workshop from one PC to another over the LAN we are getting the following error message:

Cannot start broadcasting (Output 1): Error 2 (can't open the file / invalid server address)

We are using the setting localhost:8000

Any ideas ?


Thanks

 

 

[DJSTU]

Following error message:
Cannot start broadcasting (Output 1): Error 2 (can't open the file / invalid server address)
We are using the setting localhost:8000

Have you setup/started the Shoutcast Server ? I'm thinking you haven't done this aspect.
Addresses:
(a) If its on the same computer use the address localhost:8000.
(b) If you have Shoutcast Server on Computer B then use address http://192.168.1.22:8000 (this is computer B's address. Note: Example address only) in Computer A with RadioBoss on it (Settings/Preferences/Broadcast).
May I ask what receiving setup you are using at the Transmitter end, like a computer, or a special streaming unit like a media box of some sorts ?
Dependant on what you are using at the transmitter end its also possible to have the ShoutCast Server located there using (b).

 

[djsoft]

radiodungog if you use the localhost:8000 server address, that means you need to have ShoutCast running on the same computer with RadioBOSS. But, it shows you Error: 2. The reason for this error:
1) You don't have shoutcast server running -or-
2) You have Shoutcast but firewall/antivirus software blocks the connection

Is your transmitter connected to a PC? If yes, you should setup Shoutcast there and use that PC address/port in RadioBOSS to broadcast.

 

[radiodungog]

DJSTU and djsoft,

Thanks for your suggestions.  We didn't know that we had to run Shoutcast but now we have followed your suggestions and it's working.

Our system is configured as follows:

1. At studio Vortexbox music library shared on LAN with MP3 music files normalized
2. At studio RadioBOSS auto scheduler using compression and streaming
3. At studio dedicated WiFi Ethernet link carrying stream to hilltop transmitter site
4. At transmitter site dedicated WiFi Ethernet link feeding stream to PC running Shoutcast server and audio output being fed to FM stereo transmitter

How are we going so far ?  Is there room for improvement on this setup ?


Thanks for the replies guys  ... we're running with a test transmission !  Jamie & Tom

 

[DJSTU]

Your setup sounds reasonable to me. But its not just a matter of making noise, you have to ensure your transmission is good quality and consistently so.
Some thoughts:
(1) Preferences/Playback/Miscellaneous
     Enable the Low Pass Filter at 15,000Hz
     This will assist with deviation levels. You might like to do some research on LPF.
(2) Does your Transmitter have a Meter on it, in particular a Deviation measurement which you should check is peaking at 75% (sometimes a different scale may be used, other than %, but the aim is the same, 75% of whatever it is). If its going over then you have a problem....you are over-deviating which is a no no. Bring it back so its within 75% by reducing the input to the transmitter, which might mean setting levels in the whole chain, not perhaps just at the transmitter end.
(3) Don't go crazy with compression levels, that is over compressing. If overdone your on-air sound will be awful in the sense listeners ears perceive it as full on noise which eventually leads to listener fatigue and so they turn the radio off to get some relief. Try to make your on-air sound be dynamic which is the more natural way we listen to sound.
Examples:
Look at your meter needle....
Over Compressed                       Bottom<<<              >>>Top
                                              Quietest                        Loudest (peak)
Between these two markers there is very little swing between the top and bottom.

Dynamic                   Bottom<<<                              >>>Top
A much greater swing, but you don't want the bottom to be too low, just compressed enough to sound dynamic.
Of course some songs are recorded so highly compressed that its not possible for them to be dynamic. You can't undo overcompressed recordings.
(4) Do you have pre-emphasis enabled. Normally this is done on the Transmitter, unless somewhere in the chain you have software pre-emphasis. Avoid software pre-emphasis if you can because for example if you listen to the ShoutCast Server, then the sound will be strangely different from what it is after it goes thru the Transmitter
(5) For good quality streaming use AAC over your wifi to the SC Server.  Since you are on a LAN you can use higher settings for this since you don't need to worry about the amount of data usage like you would internet streaming.

I am a great believer in what you are doing, that is having minimum hardware involved in the broadcasting chain. You need a little bit more hardware because of the STL link from studio to transmitter.
In fact I broadcast straight out of the computer into the transmitter very successfully, completely controlled by software, really good dynamics and absolutely no over-deviating.
When I get a bit of spare time, I will outline what I use. I make quite a bit of use of VAC (Virtual Audio Cable) and Opticodec to feed to ShoutCast (for reason that Opticodec is by far the best AAC encoder). I will also let you listen to my stream and will give you the details so you can do this.

 

[Chris Diack]

Our system is configured as follows:
3. At studio dedicated WiFi Ethernet link carrying stream to hilltop transmitter site
4. At transmitter site dedicated WiFi Ethernet link feeding stream to PC running Shoutcast server and audio output being fed to FM stereo transmitter

How are we going so far ?  Is there room for improvement on this setup ?

To my way of thinking, if the budget allows...  hardware rather than computer plus software in the studio to transmitter chain is preferable.

Take a look at this solution and I'm sure it will inspire some creative thinking.

http://www.barix.com/STL_Professional/1511/

The point is, if the computer at the Transmission site fails due to hardware or software issues, then you have a problem.

The Barix solution may be an answer.

It's being used by some industrial heavys in New Zealand and works perfectly.

 

[radiodungog]

DJSTU, all your points noted.  We have gone through your list and activated the low pass filter to 15KHz.

Pre-emphasis will be done by the transmitter.

We don't have the transmitter yet but all the other equipment is operating for proof of concept with WiFi, PC and Shoutcast and speakers replacing the FM transmitter sitting at the other end of our workshop.

This is exciting ...

The transmitter antenna arrives later today and we should have it installed and wired up in the next week or so.  Then the WiFi and link equipment gets installed.  Then a brief wait while we appeal for $2,500 to buy the FM transmitter.

Look forward to hearing from you for the next installment, Jamie & Tom

 

[radiodungog]

Chris, interesting concept and the specs on those Barix boxes are extra good.

Initially we were looking for an optical audio to ethernet converter for the studio end, and at the transmitter ethernet to audio converter.  We thought we had found such a combination in December 2010 but were unable to contact the people that advertised it.

The RadioBOSS PC is a Zotac Zbox that we selected for it's compact size, processor type and input / output combinations.  Remember that we are using a separate gadget called a Vortexbox for the music library storage so the RadioBOSS PC does not have music loaded on it's HDD.  It includes an optical audio output and we were keen to use that as our audio output feed.

These things that we found in December would have been perfect and were about $120 the pair.  December came and went and now in mid February we are after a simple short term solution to get running.

Certainly the Barix boxes are a good solution.  In fact we can see that we could use the Extreamer 100 on the hill to decode the audio rather than have to use a PC and software.  Extreamer 100 says it supports: Decodes MP3, G.711 and PCM audio files from PC or webserver as well as legacy digital and analog sources. Also from Shoutcast, Icecast and RTP servers.  And the price is cheaper than a small PC at US$195.

Chris, Gavin, any thoughts on this ?

Jamie & Tom

 

[kiwi_rock]

Hi Gavin here.

I haven't setup the Barix units before, but as Chris mentioned, they are pretty good units and used by commercial stations where full size rack units like the expensive http://www.stl-ip.com/ are just that, too expensive.

When driving a transmitter with a computer, remember to make sure you have a peak limiter in front of it (before the transmitter). You transmitter may have a peak deviation limiter built in to it?

The reason I mention to make sure of that is, if you are running a digitally compressed audio link to the transmitter site (ie:MP3, MP2, AAC), there will be vast difference in peak levels once it's decoded back to linear PCM for playback on the sound card at the transmitter site. Peaks accuracy is not maintained during MEPG audio compression then decompression, that's the share nature of psycho-acoustics. You'll find if you feed your shoutcast stream at say, -6dB, the peaks on decode will be anywhere up to around -3 to -2dB. That's 50% robbed modulation if feeding a transmitter without a limiter to control those peaks. If the btirate is say, 256 or 384Kbps (unless you're getting away with PCM to the transmitter over your Wi-Fi link), they will still screw up the peaks.

AAC is the worst off all level wise, but the best low bitrate sounding for Internet listeners. I've have a processor pre-set just to equalise audio before going through AAC ecoding, otherwise it comes out much louder at 1KHz when decoded from a low bitrate stream.

I have a slight difference of view on pre-emphasis than Stu, I am a firm believer in a broadcast processor or peak limiter that incorporates pre-emphasis and HF final limiting. The pre-emphasis curve also ruins the tidiness of peak limiting before pre-emphasis. Some software systems actually incorporate pre-emphasis and a final high frequency limiter. They can also do de-emphasis incase the transmitter has fixed pre-emphasis, but still follows the pre/de-emphasis curve so as not to overshot when pre-emphasised again.

Low pass filtering is a must, but do it once, and once only. Right at the end, as close to the transmitter as possible (if not in your FM limiter/pre-emphasis control). Running multiple low pass filters will put heavy attenuation at 15KHz and also causes more overshots because of group delay. Commercial stations here have very bland and very noisey at 15KHz, because their MPEG links are low passed, and once decoded, low passed again... the result, it actually rolls off below 15KHz because of the additional attenuation. It gives them that wonderful digital sound (digital done wrong).

Just my 2 cents.

Cheers,
Gavin.

 

[radiodungog]

Gavin,

Extreamer 100 on eBay at $195 USD.  My gut feeling is that we could start with an Extreamer 100 at transmitter site.

Okay on low pass filter at the end, I will have to check out the specs of the FM transmitter.

Dumb question, does anyone have an MP3 file with audio test tones to check some of this out ?

Jamie

 

[DJSTU]

I have been having a look at these Barix units. Unless I missed something, I cannot see that these would be any use in your situation at all. These are Ethernet based units only.
Jamie and Tom, you state you are using Wifi Ethernet. BUT these are two different systems.
Wifi is wireless and using wifi antennas.
Ethernet is hardwire based, therefore requiring wiring between studio and transmitter.
I am guessing you really mean you are using totally WIFI  for your STL (Studio Transmitter Link)?

Modern transmitters may not have old style filters built into them anymore. I know of many now that don't. Transmitters did have filters in the pre-computer days when sound processing was done entirely in hardware, and the filters were a final bastion in a long line of defence. Now that it is no longer an analogue world, transmitters have changed.
I cannot emphasis enough to ensure you have all your processing completed before it arrives at the transmitter input.
Software can now do all of what Gavin has in his posting.
My next experiment will be with RDS (using Airomate). It has some software based filtering built into it.

 

[radiodungog]

DJSTU, we have a dedicated WiFi link, units are weatherproof, powered by POE (power over Ethernet), run 400mW into 12dBi antennas which are housed inside the box.  Effectively an Ethernet cable and can be configured in various ways.

http://www.tp-link.com/products/productDetails.asp?pmodel=TL-WA5210G

Jamie

 

[DJSTU]

Thank you Jamie. That Tp-link unit is a very interesting product, so much so, I have gone and bought two myself. I was not aware that these products existed even.
Now that you have shown me what you are using, I can see they will indeed work with the Barix unit/s.

 

[kiwi_rock]

Are you using your Wi-Fi as an AP one end, and bridged client at the other? Or fully bridged both ends? I've found fully bridged can be advantageous in some situations. I use low powered Edimax units, similar to the TP-Link, for 3KM over town. I ended up using fully bridged as I use seperate subnets and routing between those subnets. In client mode, I ran in to problems with not being able to show the MAC address of devices connected to the client mode end. Fully bridged solved that and made the Wi-Fi completely transparent to all wired devices either end.

Most Wi-Fi gear will do fully bridged or even WDS these days. I like how a lot of units start at 400mW now We're only allowed 4 watts e.i.r.p including antenna gain here for digital modulation in the 2.4GHz band. But I find 4 watts is plenty.

 

[kiwi_rock]

BTW Stu, stereotool.com is an interesting tool too. But it requires a LOT of horsepower. It can do multiplex output and allows for phase/tilt and eq adjustment on the output aswell. Also requires a 24-bit 192KHz sound card to get a multiplex output from. Similar to that breakaway broadcast processor. I tried Airomate, I have a license for it somewhere (I bought it last year to play with) but he has no intention of adding phase and eq adjustments to the output, so you can't fine tune it. But it does work extremely well for RDS. I think stereotool has RDS in it. But I run it on a P4 2.8GHz, and it won't cope with multiplex output. Needs a fancy dual or quad core.

 

[DJSTU]

Yes, its really good software Gavin. It reminds me a lot of SoundSolution. Both products take a grunty computer to handle either of them. And that was their downside unfortunately, if it wasn't for that I would be more interested in using them. And yes I agree, I think StereoTool has RDS built in too from memory.
In my situation going direct from the computer to the transmitter is fine with Airomate, but say in the Aussie situation it would require a media box or computer at the transmitter end with Airomate installed.
Since I have yet to set Airomate up, I take it that it feeds the multiplex out of just one of the outputs....left or right output. Is that the way it works ?

 

[djsoft]

To my way of thinking, if the budget allows...  hardware rather than computer plus software in the studio to transmitter chain is preferable.

Why do you think that hardware piece is better than PC+Software? Anyway, the hardware solution is still a small computer. It can be internally using the same Windows XP and shoutcast Of course, some hardware devices doesn't contain an OS which means that it doesn't have unnecessary features and it's theoretically better.

Everything depends on how setup is done. Properly prepared PC solution can be very good (I had one computer running here for half a year). Also, the PC solution is very customizable, you're not limited to codecs/features which installed in the hardware.

 

[Chris Diack]

In a commercial environment I believe that hardware solutions for the likes of audio processing is a sensible option.

Much commercial equipment at remote broacasting transmission sites is designed for very long term operation.

Some equipment hardware that I am familiar with, in transmission sites, has been in service for 30 years and is still performing satisfactorily.

Professional transmission sites on top of mountains usually have a humidity and temperature controlled environment.

Failure of equipment in these situations is usually precipitated by temperature variation and consequently metal fatigue, and capacitors drying out and the like.

I just cant see a computer with a mechanical/optical hard drive being deemed reliable for processing anything curently.

However, solid state hard drives are becoming the norm and we may see computers as we now know them changing this situation...  but meantime... give me a box with no moving parts in my TX site...

I acknowledge, however, that many of todays black box's are in fact just a proprietary computer as DJSoft says.

 

[djsoft]

Here's a RAM-sticks based "Hard drive" without moving parts: http://benchmarkreviews.com/index.php?option=com_content&task=view&id=308&Itemid=60

 

[kiwi_rock]

@ Stu, yes, you just use one channel output from the sound card. You need a really good sound card though. Most 24-bit 192KHz cards (unbalanced) have various levels about 30KHz, and therefore aren't that good. But there's a few that are okay. The one Airomate suggests, is one which is flat and almost phase perfect, I can't remember what it was. I'm pretty sure it was a European card of sorts, made in France or Germany. It can output RDS seperate though, and I think you can send a pilot reference from the stereo generator to sync too, then just feed the RDS only back to the SCA input etc...