In these modern times, a radio station residing on a computer has got to more-or-less re-invent or re-discover the audio science from the past, for maximizing the quality of AM, FM or streaming.
In these modern times, a radio station residing on a computer has got to more-or-less re-invent or re-discover the audio science from the past, for maximizing the quality of AM, FM or streaming.
That sounds like the opening for a book, and I only meant to write a paragraph, regarding the fact that today I changed the bit-rate and sampling rate of my streaming station.
Some good blogs are written all the time about stereo AM and mono FM and the component devices like Innovonics 222, and this goes to the diversity of methods for achieving good sound.
Here in the KDX toolshed it’s all very simple. We do mono because the human voice is monaural, and we are mostly talk. But the music we have is important so it pays to enhance the quality.
When I say “enhance,” I’m not talking about torture, and I hope our programming doesn’t torture anyone.
For awhile we’ve been set for 24-kbps 22.05kHz, and that’s not bad. But I did some sampling to learn what big radio stations do with their streams.
KCAA 24 22
WKXW 32 22
WICC 50 44
WTMJ VBR 44
WARP 32 22
WJOL VBR 44
WJOB 24 22
VBR stands for “Variable Bit Rate”, and I like the way that sounds, but I don’t think my SAM Encoder Plugin can do VBR. It does CBR, “Constant Bit Rate.”
All in all, I liked the way 32-kbps 22kHz sounded, so that’s what I’m using now.
It seems smoother. Silkier. Just a tad more “present.”
Oh, and a very important chunk of the recipe is Hans van Zutphen’s Stereo Tool Plugin, an exceptionally professional toe-to-toe head-to-head match for Innovonics or any other processor.
What say you?
Here at Artisan Radio we do
Here at Artisan Radio we do 40Kbps mono streaming. Most of the material that we play is in mono, so it made perfect sense to do mono steaming. The more modern music that we play sounds good at 40Kbps (I started at 64 and reduced it gradually until there was a big dropoff in quality – it was very noticeable in the jump from 40 to 32Kbps). Testing was done with a Roku Internet radio fed into the Aux input of a good sounding bookshelf stereo system, which is probably typical for a listener (I doubt there are audiophiles listening to a low bitrate Internet stream).
ZaraRadio is used for radio automation. We use VST for audio processing (fed by a Virtual Audio Cable from Zara), with a simple compressor and a stereo to mono conversion (the latter does a much better job than just simply mixing stereo tracks, which can sometimes produce a hollow sound if they’re out of phase a bit). The results of the audio processing are fed (using another Virtual Audio Cable) to Oddcast to produce our stream, and we serve listeners directly with IceCast. We used to use an Inovonics 222 when broadcasting on AM, but now just directly feed our FM transmitter through the computer audio output (using VAC’s audio repeater tool).
Mono is good.
Paid a Call to Artisan
This past week I took a look at a few member websites, and paid a call to Artisan Radio. Everything looked good and the program schedule was very attractive, but for some reason I failed to get a stream. Maybe it was turned off at that time.
I’ll try again this next week.
ALSO, curious about Artisan’s findings regarding a quality difference between 32kbps and 40kbps, I have switched up to 40kbps 22.05kHz for the rest of the day as a test…… I tend to listen on high quality table radios, not stereo speaker systems, and that is a slightly different kind of sound.
THE other side of the stream rate puzzle is that many computer listeners have slow, perhaps older computers, which start skipping at higher bit rates. In fact for a while I streamed a 16kbps stream for dialup listeners, but then I came to the conclusion that dialup subscribers are so pinched for bandwidth that they do not tend to stream anything, because it leaves them with very little room for browsing.
The Mighty Crow
Here at the Crow, since it’s nearly an all Music Station, my stream is a bit beefy.
128 kbps MP3 (CBR) 44khz Stereo
Eventually I plan on adding an AAC Stream for mobile users.
MONO AM – STEREO STREAMING
MRAM 1500 streams 56 kbs/22.5 kHz stereo.
For the most part the limiting factor is some of my MP3 files were heavily compressed and begin to sound swishy.
But, the better MP3’S sound at least CD quality.
My DSL upload is limited to 1.5 mbs.
Still Wondering
Ya, the upload speed of the internet service puts a cap on how many listeners can be served, and lower bit-rates allow more listeners. But that only matters for us who stream from home. The streaming services are priced in terms of bandwidth vs. listeners, and more investment is all it takes.
Trying to guess what listeners will tolerate is part of the game. I’ll bet there are some listeners who only listen to high bit-rate stereo. But a lot of the professional broadcasters don’t seem to worry about all that, many of them are low bit-rate mono.
Right now, running at 40kbps 22.05kHz, I agree with Artisan Radio, it is noticeably better than 32kbps 22kHz, and the difference is even apparent on the AMT5000/3000 transmitters, where voices now sound “live.”
Not Necessarily
“The streaming services are priced in terms of bandwidth vs. listeners, and more investment is all it takes.”
Not always. The stream servers I use do not base rate on bandwidth utilization. They are based on listener slots.
I took advantage of a sale over at Shoutcast Unlimited and grabbed two 100 slot servers (a 128kps and a 48kps) for less than 40 bucks a month.
My AAC+ stream server, a 24kps 44.1Khz 300 slot server was tossed in as a promotion trade. It costs me nothing each month.
I also do re-selling of stream servers for Shoutcast Unlimited.
The prices are just a tad higher than of 4 years ago but even the current rates are very low cost compared to some stream server providers charging twice what I pay for just one mere 20 or 30 slot server.
The reason why some of those other stream providers cost so much is that they also handle the necessary licensing fees for ASCAP/BMI/SESAC which makes the rates skyrocket for mere 20 or less slot servers. And some of them require your stream to link from THEIR sites…not yours in order to meet the DMCA regulations.
Do the research and you can find excellent deals on these things. Not to mention…save a lot on your own connection headroom and put the load elsewhere instead of on your computers running the DNAS.
And its more secure. Having the world tune to a co-located server on a major data center with all the necessary security in place and far bigger pipes to the net, and at the low prices is worthy of consideration.
Also many of the station directory sites are starting to list stations based on their listener capacity. For example, iTunes will not list your station’s stream unless you have a MINIMUM capacity of 300 slots. A few others are requiring at least 100.
And the more listings your stations appears on, the better exposure and potential for new listeners.
Advertisers also take into account the total number of listener slots your station can handle. The more slots, the more potential listeners to hear the advertisement.
Regarding the typical home internet connections…unless you bought a dedicated IP with dedicated bandwidth, your ISP can change your IP addresses at ANY TIME without notification and that creates a real problem for your listeners and the listen links on your websites. ISP’s do change their IP address tables frequently for expansion and maintenance purposes. Your IP today may still be the same as it was last year, but who is to say if and when the ISP decides to upgrade and revamp their entire IP table and your thrown to a whole new IP cluster.
They are not required to inform you of that either.
So when it does happen, either your listeners tell you they cannot tune in, or you find out yourself by checking your listen links to see if they still point to the correct IP.
Also if you do not have a dedicated (static) IP and non-shared bandwidth..which 99.99 percent of the typical neighborhood home connections, DSL or Cable, your bandwidth is shared with everyone else on your block’s tier…meaning during heavy net traffic times on your tier, your NOT getting 1.5Mb up or even the touted mega speed download either. Streaming requires constant and steady data transmission and is totally different from the occasional data requests made from web browsing and email sending/receiving.
When the tier becomes loaded with heavy net traffic, which most are utilizing the download capacity of the tier to watch videos or movies or other streaming things, that chops away at everyone’s UP capacity so that the tier does not bog down and lock up.
ONLY by purchasing dedicated bandwidth and static IP address, which is usually a business type connections, can you be assured you have enough up and down capacity as well as static IP address that will NEVER change.
If these things have not happened to you yet…does not mean it wont when you least expect it.
RFB