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Barix question

I'd like to set up one or two more outlets for my AM 1620.
I have a friend 3 miles south of me, who owns a 3 story industrial bulidng 5 miles south of his place.
I looked at the Barix web site, and hope I'm understanding everything correctly.
I'd need an "instreamer" , 2 exstreamers, and I'd build up two more part 15 tube transmitters myself.
I'd like to send out a 192k mono mp3 stream.
Will my DSL "lite" AT&T at 325 kbps upspeed glitch or blank out serving this to the 2 remote locations?
I don't forsee any overlap problems with the proposed spacing.
Will the instreamer and 2 exstreamers be all I'd need?
Will I need a faster connection?
 
You might want to email dana at barix.com.he is the barix go to for north america.Post here under laguy,maybe you can pm him.also yahoo groups has a barix site.You can always email the barix folks,they usually get back fairly fast.
 
Tom, it would probably work, but you may want to look at their AAC streamer. You can accomplish pretty much the same sound at 40 kbs rather than 192. That would be sufficient for AM and then some.
 
You will need a static Public IP address at the send end. Another way to do it is by signing up with a Shoutcast provider. Sometimes their monthly rate is cheaper then the DSL's provider for a public static IP. Use 22.05 kHz MPEG2 coding, mono, with a quality level of 4. That will consume about half your 325 kbps bandwidth and sound FAR better then any AM transmitter can.

FYI...the cheapest national ISPs I can find that I can find with public static IP addresses are Speakeasy and DSL Extreme. Both offer static IP DSL for about 50 dollars a month.

I've also been considering doing something with part 15 based upon the population density where I live (Hollywood). I'm considering getting/building this transmitter:

http://www.northcountryradio.com/Kitpages/am88.htm
 
LA Guy is right. I don't have a static IP address where I live in Mexico, and stream my radio show to the US through a Shoutcast stream. I go through serverroom.us and the charge is minimal.
 
Thanks for all the help and suggestions. I'll be studyng this more, but it will be just an idea until I am employed again or my brother and I sell my parents' house and have some money to play with. For now, I will enjoy what I have and can run for next-to-nothing.
The wonderful thing about pt 15 is no costs once it's up and running. Well, no more than leaving a light on.

elchupacabras said:
Tom, it would probably work, but you may want to look at their AAC streamer. You can accomplish pretty much the same sound at 40 kbs rather than 192. That would be sufficient for AM and then some.

I've worked really hard to achieve high quality sound. It's immediately obvious when I hear one of the 128k mp3 files mixed in among the 192 k mp3s. And that's monitoring the air signal. I'd really like the remotes to have the same high quality and +150% mod capability.
If I use 22.05 khz encoding, won't that limit the maximum definable audio to 11.25 khz?
Sounds like if want 22khz definition (to get 15khz audio) I'll suck up the whole upstream bandwidth.....
Maybe I could get AT&T to change my up/down ratio to 50/50? Probably wishful thinking...
I'll try listening for a while with my audio brickwalled at 11khz, and see if that would satisfy my picky ear.
I'll check out shoutcast services.
 
Here is a direct link to Barix's site regarding audio bridging.
www.barix.com/Audio_Bridging/1161/
The Instreamer can serve up to 8 concurrent streams, so multiple transmitter sites can be connected using just one Instreamer. It has better than CD” quality, at a bit rate of 192 kbps max. in the highest quality settings. You can use it on a private WAN. To use it as a STL, it would be useless if you had send it out on a public ISP. Few mountain top transmitter sites have DSL!

Here is another source for interconnecting your radio station www.prairietech.us/


Steve
www.outlawradio.us
 
Tom Wells said:
Thanks for all the help and suggestions. I'll be studyng this more, but it will be just an idea until I am employed again or my brother and I sell my parents' house and have some money to play with. For now, I will enjoy what I have and can run for next-to-nothing.
The wonderful thing about pt 15 is no costs once it's up and running. Well, no more than leaving a light on.

elchupacabras said:
Tom, it would probably work, but you may want to look at their AAC streamer. You can accomplish pretty much the same sound at 40 kbs rather than 192. That would be sufficient for AM and then some.

I've worked really hard to achieve high quality sound. It's immediately obvious when I hear one of the 128k mp3 files mixed in among the 192 k mp3s. And that's monitoring the air signal. I'd really like the remotes to have the same high quality and +150% mod capability.
If I use 22.05 khz encoding, won't that limit the maximum definable audio to 11.25 khz?
Sounds like if want 22khz definition (to get 15khz audio) I'll suck up the whole upstream bandwidth.....
Maybe I could get AT&T to change my up/down ratio to 50/50? Probably wishful thinking...
I'll try listening for a while with my audio brickwalled at 11khz, and see if that would satisfy my picky ear.
I'll check out shoutcast services.

No.

This is MPEG2. You don't halve the bandwidth to get the maximum frequency as with MP3. With MPEG2. it's already been done for you. Please note that 22.05 is exactly half of 44.1.

Running MPEG2 22.05 kHz, you will have a flat frequency response from 20 Hz-22.05 kHz.

Also, The Barix Instreamer uses Variable Bit Rate (VBR) streaming. This automatically adjusts the streaming based upon the audio content. 192 kbps VBR is a nominal rate-the actual rate could be anywhere between 128-256 kbps at any given time based upon program content. The quality of 192 kbps VBR is considered the same as 256 kbps Constant Bit Rate (CBR).
 
Thanks for links, Steve. I really love the idea of a microwave link, but I'm in a FLAT city, and even up on my roof there's no clear shot
straight south where I'd need to squirt a signal. Now if I could get the hospital across the park to let me set a dish up....
guess I'd still have trouble seeing the target.

Shoutcast prices are OK, but I have more processing after the computer that I want to keep (mostly the Hammond reverb) so I like the idea of using an actual live air monitor feeding into a barix instreamer rather than running another computer for the upstream. The mike and "board" are also not feeding into the computer, but mix in after. I'm also a litle bit too independent minded to use a streaming service.
I'd much rather invest in boxes, and really like boxes that aren't PC based, even though the station runs on an old IBM thinkpad, which is upstairs, and the studio is downstairs, and I control it on LAN remote access software...(long story, don't ask).
It leaves this laptop free for everything else, without any chance of crashing the station.


LA Guy, Thanks for the info on encoding rates, this makes the Barix sound even better to me. Variable bit rate would be much more efficient with my "DSL lite".
I'm listening now with an 11khz brickwall, and few listeners would ever have a setup to hear anything beyond that. It's plenty crisp.
Just want to avoid the low-bit smear effect, which is much more annoying than simple rolloff of high frequencies.
The sample Shoutcast speed/sound comparator reaffirmed for me that 128k mp3 is the worst I could ever stand to put out, or listen to.
 
Goran Tomas said:
Sorry to not have time to elaborate, but I would say "there's too much confusion" here...


Regards,
Goran Tomas

Which I'll interpret as: I'd better think of using the highest quality seting in a Barix that my "DSL lite" will support, or I'll begin hearing
the effects of cascading codecs. Or even: I'll be hearing cascading codec artifacting no matter what I use.
 
Tom Wells said:
Thanks for all the help and suggestions. I'll be studyng this more, but it will be just an idea until I am employed again or my brother and I sell my parents' house and have some money to play with. For now, I will enjoy what I have and can run for next-to-nothing.
The wonderful thing about pt 15 is no costs once it's up and running. Well, no more than leaving a light on.

elchupacabras said:
Tom, it would probably work, but you may want to look at their AAC streamer. You can accomplish pretty much the same sound at 40 kbs rather than 192. That would be sufficient for AM and then some.

I've worked really hard to achieve high quality sound. It's immediately obvious when I hear one of the 128k mp3 files mixed in among the 192 k mp3s. And that's monitoring the air signal. I'd really like the remotes to have the same high quality and +150% mod capability.
If I use 22.05 khz encoding, won't that limit the maximum definable audio to 11.25 khz?
Sounds like if want 22khz definition (to get 15khz audio) I'll suck up the whole upstream bandwidth.....
Maybe I could get AT&T to change my up/down ratio to 50/50? Probably wishful thinking...
I'll try listening for a while with my audio brickwalled at 11khz, and see if that would satisfy my picky ear.
I'll check out shoutcast services.

Who's transmitter are you using?

AT&T has a synchronous DSL but the up down speed is the same as their speed on any of the dsl packages without the return. 128 up/3m down is 128/128. Make sense? You can use two dsl packages cheaper.
 
As an owner of two Broadcast Warehouse FM transmitters, I too am picky about our sound quality. The Barix offers a cost effective means of linking a studio with several transmitters. With a private WAN, I don't have to worry about bandwidth problems with a ISP socking it to me for going over their limit.

I really love the idea of a microwave link, but I'm in a FLAT city, and even up on my roof there's no clear shot straight south where I'd need to squirt a signal.
I have been able to bounce the signal off a reflector to get the signal around the corner; everything has to be right to make it happen, but it can be done in a pinch.

Using Hamilton Rangemaster transmitters in our network, we find the Barix works for us! Delivering the sound quality we require to take full advantage of the Rangemaster's abilities. Having the operation totally off the grid has saved us a ton of money; we have yet to get a bill from the sun or wind supplier, operational cost are just about nothing. While the Barix may not deliver so called CD quality, the fact is in the real world; the average listener is never going to notice the difference after processing and passing through an AM of FM transmitter.

Unless the government is sending you a bailout package; the Barix offers the most bang for the buck for interconnecting your facilities. For live remotes; the Prairie Technologies! www.prairietech.us/ microwave links beat the hell out of cell phone remotes in sound quality, and you can pass video too! Allows the guy back at the studio to watch the high school football game too. Keeps them awake and paying attention!


Steve
www.outlawradio.us
 
XRQKFM said:
the average listener is never going to notice the difference after processing and passing through an AM of FM transmitter.

And how would you know?

I hope you don't expect your listeners to call in and say "you have too much coding artifacts in you sound". Or, for that matter, "you are using too much clipping".

Average listener doesn't have a slightest clue what MP3 is and/or what processing is! They are completely clueless as to what is used in radio and how it works. But that doesn't mean they, consciously or subconsciously, don't like something they are hearing. However, those who actually consciously realize they don't like the sound, probably make up less than 20% of your audience. Of those 20%, those who will feel that this is enough of a reason to object to the station and that they can or have the right to do so, probably make up less than 1%. Of those 1%, those who will make an effort to find out the phone number and/or e-mail of the station and then make another effort to make the call or spend time writing you an e-mail - you are now in promilles of your not that big audience anyway. And if that call to the DJ or an e-mail ever happens, question is if it will ever get to you. And if it does, what will you do with it.

To use another refrain, "it's such an illusion"...


Regards,
Goran Tomas
 
ChiefEngineer said:
Tom Wells said:
Thanks for all the help and suggestions. I'll be studyng this more, but it will be just an idea until I am employed again or my brother and I sell my parents' house and have some money to play with. For now, I will enjoy what I have and can run for next-to-nothing.
The wonderful thing about pt 15 is no costs once it's up and running. Well, no more than leaving a light on.

elchupacabras said:
Tom, it would probably work, but you may want to look at their AAC streamer. You can accomplish pretty much the same sound at 40 kbs rather than 192. That would be sufficient for AM and then some.

I've worked really hard to achieve high quality sound. It's immediately obvious when I hear one of the 128k mp3 files mixed in among the 192 k mp3s. And that's monitoring the air signal. I'd really like the remotes to have the same high quality and +150% mod capability.
If I use 22.05 khz encoding, won't that limit the maximum definable audio to 11.25 khz?
Sounds like if want 22khz definition (to get 15khz audio) I'll suck up the whole upstream bandwidth.....
Maybe I could get AT&T to change my up/down ratio to 50/50? Probably wishful thinking...
I'll try listening for a while with my audio brickwalled at 11khz, and see if that would satisfy my picky ear.
I'll check out shoutcast services.

Who's transmitter are you using?

AT&T has a synchronous DSL but the up down speed is the same as their speed on any of the dsl packages without the return. 128 up/3m down is 128/128. Make sense? You can use two dsl packages cheaper.

My own design and build transmitter. Colpitts crystal controlled 6V6 osc, 3 6SN7s for audio, mic inputs for carbon mike and hi-z mike, line input, audio mixed with RF in the last 6SN7 in a Van der Bijl modulator (mixed on the control grid), that feeding a type 78 voltage amp, that feeding a 6L6 voltage amp, now modified to only pull 100mw. It was originally designed to drive 4 807s in parallel running class AB1 (no grid current) to make about 135 watts.
The last stage was never built, but I have all the parts. No iron anywhere in the audio path. Feeding an FM stereo signal to it, I can hear the 19khz pilot as a 1khz beat against the signal 20 khz over, so it's got fine frequency response.

There's a picture of it on this podcast page, along with airchecks from it, crushed down to 96k mp3, even though I sent up 192k mp3s.
http://thomasjwells.podomatic.com/
It does look a bit neater today. In that picture it had been running about 7 years with no PM. Note the antique tapped inductance box and Atwater Kent tuning cap.

My DSL is the cheapie single copper pair with modem at the service entrance, I doubt there's enough BW to do what I want.
It is designed for consumer home use, and probably can't be re-proportioned for a different up/down split.


I don't advertise or have any feedback methods for listeners to call, so it's up to me to make sure I'm satisfied with the sound.
 
Tom, what trip! Your processing reminds me of the AM's I grew up with back in the 1970's. Thick and rich. It was kind of cool hearing the record scratches on the demo tracks as well.
 
I'd imagine that transmitter sounds very good in person. Back in the 1980s, I built a 5 watt Carrier Current transmitter using Heising modulation. I'm sure the circuits were similar. I'm assuming that your output voltage amplifier is running linear (class A), so its efficiency would only be in the high thirties. When you leave room for the sidebands, that means that your carrier output would be somewhere in the 10 mw range? Is that right or am I missing something?
 
And how would you know?
We ask questions! And plenty of real world experience!
The keyword you may have missed was average
We have done extensive listener testing over the years; we actually ask what they think sounds better.
ABC comparisons are one way we test; we take the same song synced and play it from three sources: a broadcast cart, mp3 & and directly from a CD. You would be surprised how many liked the cart the best; listeners in the states may not be as discerning as in Europe; I know when it comes to video they aren't. Fact is some listeners don't like the sound of a CD either; and swear vinyl records sound better.

Goran, name a better way for a small broadcaster to link up multiple transmitters for under $1000 without a major sacrifice in sound quality or requiring a license. The fact is the Barix is a cost effective way for a broadcaster on budget to link up a studio with transmitters in multiple cities or locations. Some day you might want to pay a visit to the United States, listening to what is broadcast and how it sounds here in the states; and not just the major markets. One visit and you will quickly realize sound quality is not a high priority with broadcasters here; markets large and small leave allot to be desired. Those few broadcasters who program locally, are airing MP3's 128kb -192kb straight off a consumer computer using at best a Creative Labs sound card. Some broadcasters will go the extra mile running WAV files, use a good sound card; but they are few.

We have a station that uses a BW FM transmitter, only peak limiting in the audio chain, only CD's as a music source on the air and no STL to muck things up. It's as straight wire as you can get;Very few listeners notice the difference, so I understand why some broadcasters don't bother going the extra mile. We have a 100% vintage analog radio station playing vinyl, reel to reel and cart for program sources; processing is analog; Some listeners call telling us they like the fat sound, and the old analog sound. Those that notice and call, often are other broadcasters asking how we get away with it;meant in a positive way. To run a straight wire operation you need a skilled engineer at the board to ride gain; most of todays board ops don't even know what or where the transmitter is.

Sometimes we have to live in the real world! Today it is like pulling teeth to get an artist to send us a CD, typically it's an e-mailed mp3 at 128kb, and if we are lucky it's 192kb. The spots from the nationals are also e-mailed too, as are the PSA's. It's almost pointless to exceed your source material, not to mention being very costly.

So when I say the average listener won't notice; I speak from experience, after 43 years in the broadcast business I know they don't, again the keyword is:average.

Back in the late 80's, I notice when a radio station CD107 tried to pass off a cart machine as a CD for a music source; not only did I notice, but I could tell which cart machine they are using, much to the shock of the programmer of the station. But he and I knew, I was the exception not the rule and he could keep on passing his carts off as CD's. Today in the real world, most people are listening to us on boomboxes of one kind or another or in their noisy cars yakking on the cell phone. The Ipod has changed what most people perceive as good quality sound, the rapid decline of CD sells proves few care about sound quality here in the states. I dare say a majority of listeners would not know an uncompressed recording if they herd it, that is the way it is in the real world.


Sure guys like Tom and I, will go the extra mile to have our stations sound the best they can, but few will notice or care; for us it's personal. In the real world, listeners are just glad to have a locally programmed radio station that plays the music they like.



Steve
www.knjoradio.com
First stereo FM station west of the Miss
 
LA_Guy said:
I'd imagine that transmitter sounds very good in person. Back in the 1980s, I built a 5 watt Carrier Current transmitter using Heising modulation. I'm sure the circuits were similar. I'm assuming that your output voltage amplifier is running linear (class A), so its efficiency would only be in the high thirties. When you leave room for the sidebands, that means that your carrier output would be somewhere in the 10 mw range? Is that right or am I missing something?

It's not exactly linear, the non-modulated input power is about 50-60 mw, but has room for about 300% positive modulation when I've tested.
I don't push it that hard, though. It starts to clump up most receivers' AGC at anything over 200%, so I push it to 150% and figure the average power is right around 100 mw input. If I wanted to really get into trouble there's more than enough boat-anchor equipment lying here ready to go.
I can't afford to offend the powers that be. But when LPAM is eventually permitted, I am ready, if I'm still alive by that time.

I stayed out the businesss, but can never "give up" radio. For myself and others, it's a hobby not only to make music come out of the box, but to see just
how good we can make it sound. I'm competing with myself and my previous best efforts.

A LOT of my music is from 45s. I clean up some noise and scratches, but would never want the utter "purity" of CD source music.
Character is a combination of scars, wrinkles and original beauty. Oh, and cue burns, too.
 
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