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Discussion Starter #1
Sorry, I have no idea where to post this:

I am getting gear ready for a Florida snowbird condo. But never having used "cable" services (like Rogers), I have no idea what comes out of their pre-paid jack in my condo (even though I am reasonably sophisticated about electronics otherwise).

For example, if the cable company is carrying PBS FM 94.7 Miami, will it show up somewhere 88-108, and I can just connect an FM tuner directly? Or what?

Will I find the sound lousy and instead sneak in an OTA antenna? Are there high-quality aftermarket cable "boxes"?

Thanks.
 

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Really don`t know what you are asking but maybe this will help.

Cable company`s distribute the radio station signals to their subscribers via digital cable (don`t think anyone uses distributes on analog anymore since it uses too much bandwidth) in the same way they distribute TV stations.

It`s encrypted so you need a Digital Cable set top box and a subscription. Once you do, you tune to the channel you want (PBS FM maybe on channel 954 or something) and you have music. To get it to an AV receiver, you output via HDMI or analog audio cables or toslink.
 

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Discussion Starter #3
Hugh - very helpful. So my question really is what comes out of the box?

I guess the HT is HMDI (single-plug component) and there is yellow-red-green (baseband video/audio) for old analog sets (or channel 3)?

What comes out when you select an FM broadcast at 954 or something, L and R (and also on the HMDI pins, I suppose)?

If so, is there any reason for a hifi person to buy an aftermarket hifi cable box, say with vacuum tubes (that's a joke!!!)?

Hard to beat the quality of our OTA HT and FM reception in Toronto. Will the cable signal and D/A box offend my golden ears?
 

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Really not sure what you are asking.
 

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Discussion Starter #5
All the questions above, but if limited to one good one: what is the output when you remote selects "954"? Is it an audio signal or an FM RF signal?

How are FM-HD stations handled?
 

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Having worked at a radio station, the signals have been compressed, synthesized, modulated, demodulated, analog to digital converted, digital to analog converted many times over before they reach your tuner. No one plays records anymore. The music libraries have been converted over to mp3 or other digital format and stored on a server.
Garbage in, garbage out.
I'm not sure what perfection your golden ears can hear.
 

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For those cablecos that do still send out analog FM signals (EastLink in Halifax and Shaw throughout western Canada for example).... it is a modulated FM signal...
Its the same technology (but much more robust) that lets you use the FM tuner in your car to listen to an external mp3 or CD player.
 

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The "signal" that comes from the STB (set top box) can be either PCM or DD2.0 depending on how you set your audio options on the STB. I believe that most of these digital music channels have a bitrate roughly equivalent to low quality MP3 and come into the STB as DD2.0.

To answer the original question, what comes from the RF-coax cable is QAM which needs to be received and/or decoded by a QAM tuner. Most service providers do not encrypt the music channels (Galaxie or FM), so they can also be picked up via a QAM tuner, while for encrypted signals a STB from the service provider is required. For the sake of clarity I've left out the analogue TV channels and the analogue FM channels. The latter are not available from most providers any more.


As for connections, check out the following FAQ:

http://www.digitalhome.ca/forum/showthread.php?t=76085
 

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Discussion Starter #9
My head is spinning from well-meant replies that verge wildly (and in the same post) from totally obscure references to "DD2.0" to links at the intellectual level of "turn the knob marked volume control clockwise..."

In as much as I have actually seen TVs plugged into these STBs, I have reason to believe the outputs are easy to explain to me.

PLEASE: what jacks are on the back of the STBs and what kind of signal comes out of them when the remote selects an FM station? Is it ordinary "flat" audio or is it RF in the FM band, or what?

I have never seen a cable box and have no idea what they do or what jacks or controls they contain. But OBVIOUSLY I know the difference between FM-modulated RF and baseband audio and Dolby-encoding and MP3 audio..... and what optical jacks transmit...!

Thanks.
 

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hey Ben,

I think the first question you need to answer is who the cable provider is at the condo. Not all cable providers use the same hardware STBs. Once ya know what make/model STB they use, ya should be able to google around for owner's manuals and such. You can also lookup online at the provider's website whether they even carry any local FM radio stations in their service.
No, I don't think ur gonna be able to just go out and buy your own STB and use it.

Where I live, when I was growing up they used to just put the FM radio stations on the same frequency that they are on over the air. U just connected the cable to your FM Stereo and u were good to go. I do know local FM radio does not show up on our STB though. So, maybe they don't even offer any FM radio anymore? Fairly certain they don't here, but of course I don't live in Miami. So find out who the provider is down there.
 

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Ben: If you use a digital audio connection (like optical or coaxial audio) to an AVR, you'd be able to get PCM (Pulse Code Modulation - a type of audio signal) or DD2.0 (Dolby Digital two-channel audio) from that connection. If you use an analogue audio connection, then you'd get stereo (2 channel) audio. The original signal, as stated before, has been compressed to use less bandwidth and would be equivalent to what you'd hear from an MP3 player and not as good as a CD after passing through the STB.

I'm sorry if some of this goes over your head, but with some understanding of what each of these things means, perhaps you'll have your answer. Here's an acronym FAQ if that's bothering you and if you need more info on an acronym, type it into Google followed by Wikipedia and they'll usually have a nice long explanation of what it is. We can't guess what you are and are not comprehending at this point. If you want specific answers, you'll need to ask specific questions.

http://www.digitalhome.ca/forum/showthread.php?t=17715
 

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Hi Ben,

Everyone has answered your questions, but the problem is there are many permutations that defy a simple straight answer, and as majortom has correctly said, the cable provider will be the key to homing in on exactly which boxes are used, and if there is any analogue FM service.

And, it can be safely said that basic digital boxes will definitely put out an audio baseband (L/R) (White/Red) analogue signal. Whether Toslink or HDMI or SPDIF via RCA coax connection is available depends on the box and whether the cable company has enabled them.

I can almost guarantee that HD Radio (the extra HD channels) will NOT pass through a cable head-end in an analogue setup. It's not meant to pass that stuff, just the regular FM signal will make it through, and then often with various forms of degradation.

So... Find out who the provider is, talk to others in the same complex as to the services provided and get a list of the boxes the provider supplies. Once that is known, then more research will net what audio options you have.

Cameron
 

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Discussion Starter #13
Thanks for three very clear and helpful replies. Much appreciated.

I guess it would be fair to say you are at the mercy of the cable company as to the degree of compression they impose on sources. I take for granted that the compression has noise, distortion, and is "lossy" like most stronger compressions. There is also the matter of where the cable company gets its stations since even digitally-encoded signals are received analogly as they pass through the ether or even in optical cables. So cable is unlikely to provide sound any better than the pictures I've seen, as compared to local-reception OTA.

(A separate question I wonder about is what measurement standard is applied to visual and sound signals to capture the degree of degradation arising from MP3, Dolby noise reduction, A/D or D/D conversion, etc?)

Sorry to hear that FM-HD is unlikely to survive the regular-FM channel-sized compression.

We are likely to live with the cable TV feeds. I assume the cable STB provides SDTV feeds as well as HD.

But I'm going to run an FM-Fool plot on my pending Delray Beach, FL, low-rise condo address to assess the OTA FM potential.

Many thanks for these and further replies.
 

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I don't know if they still have it, but Rogers had analog FM on the cable. The audio quality was significantly poorer than OTA and they generally used different frequencies than broadcast. These days, you can receive many radio stations via digital box. In addition to the radio stations, there are several music channels, in various themes, available. Every digital set top box I've seen has plain old analog audio out, as well as HDMI and optical or copper digital signal on HD boxes. Any of those could be used for listinging to radio stations. Here, in my living room, I use digital over copper to connect to my AVR and in my computer room, I use analog audio to connect to a stereo receiver.
 

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Guys ... please ...

I think the answers have been given anyway ... but I will try my version:

1. If the cable co provides Analog FM straight from the Coax:
Then - may need coax splitter, and coax feed to the antenna inputs of the FM receiver, usually with a little 75-300 ohm transformer (balun) to match the antenna input terminals of the FM receiver. (analog FM over cable is alot more rare these days - still have it w/COGECO Kingston)

2. If it's Digital Service only w/Digital Box for music or FM radio stations on digital channels ... (no Analog FM) then:

- hook up a TV to the digital box and listen over that first by tuning the right channels on the digital box (connection types: RF ch3/4 to TV, Composite R,W,Y cable to TV, S-Video and audio cables to TV, Component RGB and audio cables to TV, HDMI to TV) That'll give you and idea what content is available to you.
(some people just listen over their TV - and that is good enough for them. Some TV's have o.k. sound and decent speakers)
- TV may have audio output, via say standard RCA type connectors. Left and Right to one of the inputs of the stereo for better quality sound (better amp and speakers w the stereo)
- or ...Connect audio cable straight from the Digital Box audio out, to one of the inputs of the FM Stereo
(I did this at the Flop house where I stay in Ottawa - sound quality is likely better since it does not pass thru the TV)
This connection could be a simple stereo Left Right, Red White RCA audio cable.
-or- if you have more high end audio equipment and Digital box ... it might even be something more complex like: Optical Cable (digital audio via fibre optic cable), Digital Audio via a coax cable and connector, never seen it but HDMI cable, since that carries digital audio (I believe).

- Suggest you get a channel guide for ... from the Cable co ... so you know the channel listing - what is offered and which channels to tune / search.

Size up what you have, Digital box and Amp or FM receiver ...
And then you'll have some idea for some connection possibilites.

Yes, you may have to consult with the Cable company there - and they'll give you some ideas for the "BEST" way they recommend for you to do it, based on the equipment, and the services they offer.

There may be some "configuration" required ... i.e. going into some menus / software configurations of the digital box and/or the audio Amp/receiver and activating inputs and outputs etc. switching to the right input or activating the right input or outputs etc.

At the flop house I was just able to connect it up, switch the amp/receiver to the right imputs, tune the channel on the Digital Cable Box - and out came SOUND. Not too hard.

Actually, if connected and configured correctly, the sound might be quite allright - pretty good. Maybe not AUDIOPHILE quality ... but what we have hooked up here at the Flop house in Ottawa is fairly good.

Analog FM over Coax, sound quality can suck a little, noisy, raspy, interference - but will give some listening options.

Digital Music Channels / audio over digital box - sound quality is not bad, so so.

FM straight over good antenna - good signal - is usually pretty good.

HD Digital radio - over antenna - I have read posts saying it is really good quality. If you are in Florida, in the U.S. I am not sure if you may have some HD radio options - direct over the air - but you need a special HD digital radio receiver.

Now if you have a home theatre hooked up with your TV - ex 5.1 surround sound then that system itself should be capable of good sound quality ... and it will then depend on the quality of the source of the music from the Cable co. system and equipment.
 

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I am going to add my two cents.

Any normal cable box you might get (except the DTA boxes some providers offer), will have at least analog stereo audio, if not some sort of digital audio.

You can connect that directly to a stereo system to listen with the TV off. I do that with the radio/music channels on satellite all the time.

You probably need to get the box from your provider. Cable boxes are not usually sold on the open market in the USA. A clear Qam capable box may work, but I wouldn't practically count on it.

I hope by the quoted term "aftermarket" one does do not mean a pirate box. In addition to us not allowing pirate discussion here, I don't even think there are such things as digital pirate boxes in the USA.
 

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Discussion Starter #17
Again, thanks for helpful replies. Sorry - I guess I was thinking that cable companies control "the flow" at the source by sending out the cable guy to disconnect your home service, not at the box! Or that they "meter" your usage somewhere upstream like a water meter.

I gather cable as an erzatz-antenna is a thing of the past. Modern large commercial systems stuff all the signals into a digital line right to the STB.

I gather QAM is a type of digital signal and modulation standard and that the "500 channel" universe and program schedules, etc. are multiplexed on it? Is it always a "fire hose" or can the cable company configure the cable signal to suit the customer's long-term or momentary choices... or is all the selection in the box? (I won't ask how the cable company knows what to charge the customer for pay-per-view services.)

Soooo, there are questions about the quality of the demodulation of the FM signal somewhere before the audio-out jacks of the box. And that signal (wherever the cable company accesses it into its system), has a few modulations and demodulations to pass through before the audio-out jacks (and only some of them, like into optical-output, are in the digital family). Pity there aren't legal after-market hifi-grade boxes since I want to hear hifi FM, not something coming from a poor-quality STB.

Likewise, I'd hate to gather my FM programs from the audio-output jacks of my consumer-grade TV, if the FM signal ends up in the TV band. Makes a hifi guy shudder.*

My Florida FM-Fool plot is very favourable to FM OTA. Strong public and university stations in two concentrations 160 degrees about. Perfect for a stationary low-gain antenna with poor front-to-back ratio! On a good night in Toronto, I get 80-mile PBS FM-HD who have a very low antenna in the little town of Boston, New York (no kidding) and always excellent FM-stereo.

Again thanks and I guess I am getting better as explaining my cable-newbie puzzlements since the answers are getting so much better.

*BTW, I am a hifi nut, but definitely not what is derisively called a "Golden Ear" who judges sound quality mostly subjectively.
 

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Yes, QAM (and its related modulations for satellite and other media) is "The 500 channel" universe, with the channels multiplexed onto a number of QAM muxes, and access granted to subscribers on a per-box basis with addressable digital boxes, mostly. VOD/SDV (not specifically related to your desire for audio), does allow individual selections be put onto the cable at the head-end (on a per node basis). Most of the time providers leave the cable connection as is, and trust the user will do the right thing and subscribe to the cable service.

As for the audio path, if the provider does not have a direct connection to the station, it will have a commercial grade FM tuner, which directly feeds an endcoder, whose digital output goes to one of the QAM muxers.

For modern "Hi-Fi", you would get a receiver with a digital audio in and use its decoder/DAC. The cable box would just be passing the digital bits on from the provider exactly as they sent them to you. A "crappy" box will not degrade the digital signal.

The analog audio signal, at least from my Shaw/Motorola satellite receivers, into my analog 1990s hi-fi (with 1970s speakers), is fairly decent quality.

If you get a good FM coverage, I would pursue HD-Radio, possibly with a boom-box or 2.1 bookshelf system.
 

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Hey Classicsat,

Commercial quality tuners? :) With what I've heard over the last 30+ years that issued forth from a cable outlet on FM, the results more mimicked discount store FM front ends of the likes of "Symphonic" or "Concerto" branded stuff...
Multipath, and massive amounts of hiss permeated even the strongest of signals... And audible distortion. The problems weren't the tuner front ends necessarily, but the conversion process to other frequencies and noisy distribution amps all contributed to the mess. It didn't help that the converted FM signals weren't on frequency either...

Just fold it to mono and use it as a background music source and it's fine....

Anything else and you'll be disappointed.

The bitrates and codec used for delivery as well as the source material will all play a part in digital delivery via a STB.

Cameron
 

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Discussion Starter #20
Yes, QAM (and its related modulations for satellite and other media) is "The 500 channel" universe, with the channels multiplexed onto a number of QAM muxes, and access granted to subscribers on a per-box basis with addressable digital boxes, mostly. VOD/SDV (not specifically related to your desire for audio), does allow individual selections be put onto the cable at the head-end (on a per node basis). Most of the time providers leave the cable connection as is, and trust the user will do the right thing and subscribe to the cable service.

As for the audio path, if the provider does not have a direct connection to the station, it will have a commercial grade FM tuner, which directly feeds an endcoder, whose digital output goes to one of the QAM muxers.

For modern "Hi-Fi", you would get a receiver with a digital audio in and use its decoder/DAC. The cable box would just be passing the digital bits on from the provider exactly as they sent them to you. A "crappy" box will not degrade the digital signal.

The analog audio signal, at least from my Shaw/Motorola satellite receivers, into my analog 1990s hi-fi (with 1970s speakers), is fairly decent quality.

If you get a good FM coverage, I would pursue HD-Radio, possibly with a boom-box or 2.1 bookshelf system.
All (or nearly all) my questions answered!!!! Thank you.

In the hifi world, the term "commercial grade" often means "durable but not the finest sound at any cost" sort of thing. So I bet your desription is apt and I bet my take-away message is "ummm, remains to be seen". As our friend CamDAB suggests.

Not sure as I can find any digital inputs on my golden-oldie hifi gear! The shortcoming is mine!*

Again, thanks.


*Includes Dayton-Wright electrostatics for mid-range speakers, for you fans of Canadian excellence.
 
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