Aural Moon Shows

[VAXman(Admin)]

Originally Posted by Roger -Dot- Lee

Unfortunately, we can only put out the quality we get. We get a 32k stream from WBZC. That's not likely to improve, since it's a college radio station, and they don't have the budget of a WNBC or KSFO (for our west coast listeners), though if you'd like to offer them a fatter pipe and a heftier server on your dime, I'm sure they wouldn't complain in the least. Barring that, my only suggestion to that is to do what I've been doing since I started listening to Tom many years ago: adjust your client to tone down the bass and treble, and boost the mid range. iTunes has a nice equalizer embedded that works wonders.

OK. Just interjecting a bit on the technical.

We get a 32Kbps stereo stream. That is not high quality by ANY stretch of the imagination. This 32Kbps can, at max, sample at 22KHz (realistically, that's pretty poor quantization at that rate too). Being that this is a stereo feed, that sampling is safely half that for each channel or 11KHz. Nyquist-Shannon sampling theorem says that the maximum frequency that can be produced is 1/2 the sample rate. So, this puts the top end around 6KHz. Not great quality? Consider that the high C (key 88 on the piano) is ~4200Hz (middle C is 262Hz, so you can figure it exactly for 4 octaves higher) the frequency spectum we get isn't very good. I'll spare you the Fourier analysis of the distortion that this presents.

That said, I live close enough that I can get Gags off of the FM airwaves. The FCC's FM frequency allocations at ±100KHz permit about 15KHz as the maximum upper frequency (again, I'll spare you the math of the Fourier integral). This is CONSIDERABLY better than we get from the Real stream. If Gags will continue, it was my plan to erect a highly selective, high gain antenna and get the show off of the FM airwaves and encode it in a higher quality MP3 stream to send to the AM server. This would also get rid of the FM preemphasis which now gives Tom's show its bassy boomy sound.

[roger]

Originally Posted by VAXman

OK. Just interjecting a bit on the technical.

We get a 32Kbps stereo stream. That is not high quality by ANY stretch of the imagination. This 32Kbps can, at max, sample at 22KHz (realistically, that's pretty poor quantization at that rate too). Being that this is a stereo feed, that sampling is safely half that for each channel or 11KHz. Nyquist-Shannon sampling theorem says that the maximum frequency that can be produced is 1/2 the sample rate. So, this puts the top end around 6KHz. Not great quality? Consider that the high C (key 88 on the piano) is ~4200Hz (middle C is 262Hz, so you can figure it exactly for 4 octaves higher) the frequency spectum we get isn't very good. I'll spare you the Fourier analysis of the distortion that this presents.

That said, I live close enough that I can get Gags off of the FM airwaves. The FCC's FM frequency allocations at ±100KHz permit about 15KHz as the maximum upper frequency (again, I'll spare you the math of the Fourier integral). This is CONSIDERABLY better than we get from the Real stream. If Gags will continue, it was my plan to erect a highly selective, high gain antenna and get the show off of the FM airwaves and encode it in a higher quality MP3 stream to send to the AM server. This would also get rid of the FM preemphasis which now gives Tom's show its bassy boomy sound.

you'd do that during all your copious free-time, Vax?

/hug

[VAXman(Admin)]

Originally Posted by roger

you'd do that during all your copious free-time, Vax?

/hug

Free time? Nah, I just sacrifice sleep. Besides, sleep is highly overrated.

[Roger -Dot- Lee(Admin)]

Originally Posted by VAXman

OK. Just interjecting a bit on the technical.

Always welcome from this corner of God's Country.

Though other members might disagree.

Anyway, on to the comments and questions:

Originally Posted by VAXman

We get a 32Kbps stereo stream. That is not high quality by ANY stretch of the imagination.

No, it's really not. I don't believe I've ever heard Gags on the 56k stream, so I can't say for certain how much of an impact this could have on sound quality. I'm sure it wouldn't be all that much as the limiting factor is still the 32k we get from WBZC.

Originally Posted by VAXman

This 32Kbps can, at max, sample at 22KHz (realistically, that's pretty poor quantization at that rate too).

I agree on the statement that it's poor quantization. I'm wondering, however, why the sampling rate is so low, especially considering that the audio is compressed before it even heads this way (I believe).

Side question: does Real Player use compression? If it can, but we're currently not, we may want to consider it. It may be a bit of extra work, but I think the benefits would outweigh the additional overhead.

Originally Posted by VAXman

I'll spare you the Fourier analysis of the distortion that this presents.

Let's talk off line.

Originally Posted by VAXman

That said, I live close enough that I can get Gags off of the FM airwaves.

How far out are you? And will inclement weather perhaps cause signal degradation as well as 'black holes'?

Originally Posted by VAXman

The FCC's FM frequency allocations at ±100KHz permit about 15KHz as the maximum upper frequency (again, I'll spare you the math of the Fourier integral).

Again, let's take it off line.

Dr. Dot, doin' some postdoc work here.

[VAXman(Admin)]

Originally Posted by Roger -Dot- Lee

Side question: does Real Player use compression? If it can, but we're currently not, we may want to consider it. It may be a bit of extra work, but I think the benefits would outweigh the additional overhead.

I don't know all of the details of Real's codecs; however, I would say it's safe to assume that the quality calculation wouldn't improve much with incorporation.

Originally Posted by Roger -Dot- Lee

How far out are you? And will inclement weather perhaps cause signal degradation as well as 'black holes'?

Well, as the crow flies, about 22 miles. As the horseflies, about 35 miles as we have to go around Lakehurst Naval Air Engineering Station. It's a 40-45 minute drive for me from home to Tom's studio. Be aware this is south Jersey and those are NOT highway miles.

As for black holes, I haven't seen any.