HDTV
The current formats used in HDTV are:
- 720p - 1280x720 pixels progressive
- 1080i - 1920x1080 pixels interlaced (most common)
- 1080p - 1920x1080 pixels progressive
Selecting Speaker Cable for House Audio
Gauge Selection
Because the impedance of loudspeakers is quite low, (usually 4 or 8
ohms) the resistance of the cable feeding the speakers becomes quite
relevant in determining how much power actually reaches the speaker. As
an example, a hundred foot run of 16 AWG cable will have a round trip
resistance of 0.8 ohms. If this is used to feed a 4 ohm speaker,
approximately 17 percent of the power will be lost to the cable, and 83
percent will reach the speaker. Larger wire will reduce the power loss.
From a practical standpoint, the wire sizes normally used for whole
house audio speaker wiring are either 16 AWG or 14 AWG. These sizes
provide a good compromise between line loss, cost, and ease of
installation. Most of the equipment available for whole house audio
systems have connection devices designed for these wire sizes. Going to
a non-standard wire size can immensely increase the difficulty of
installation.
Power Loss Budget Table The following speaker wire power loss budget table provides a guideline for selecting the right size speaker wire. Speaker Wire Power Loss Budget Table
Power Loss Budget Table The following speaker wire power loss budget table provides a guideline for selecting the right size speaker wire. Speaker Wire Power Loss Budget Table
Selecting A/V receiver
Step 1: What video connections do you need?
Does your DVD player or cable/satellite receiver use HDMI? If so, you'll want to choose a receiver that has HDMI connectivity or you will have to bypass the receiver and go directly to your TV to get the best picture quality. Going HDMI also simplifies your connections so the back of your A/V rack doesn't wind up looking like mine pictured to the right :)
Most entry level displays only sport 1 or 2 HDMI inputs so it's usually a better idea to select an HDMI-enabled receiver. Remember HDMI is the only connection method the new high definition players (ie. HD DVD or Blu-ray) are allowed to use to send HD signals (>480p resolution) from the player to your display so don't settle for component video or lower resolution connection schemes. HDMI receivers have come way down in price and can be had as little as $249 so there is almost no excuse NOT to be buying an HDMI enabled receiver today. Although we haven't tested the latest round of Pioneer receivers, they seem to be the market leader in the $350-and-under price category and their new x18-series A/V receivers that debuted at CES 2008 look most impressive.
Step 2: What HDMI functionality do you need?
Not all HDMI receivers are created equally. It wasn't until recently that the latest version of HDMI (ver 1.3a) was supported by any hardware despite it was the "going forward" standard for 1080p Deep Color (12-bit) video and True-HD and DTS HD audio support. Only HDMI 1.3a can support all of the latest formats natively, but it doesn't mean you can't get by on the lower versions, especially if the price savings makes sense. If your display resolution is limited to 1080i then older versions of HDMI will work just fine. If you don't own a high definition DVD player but eventually plan to buy one down the road, make sure the receiver you choose has multi-channel audio support via HDMI so you can have the player send the lossless decoded high resolution PCM audio signal to the receiver for it to provide bass management and proper routing to your speakers. If you think Dolby Digital and DTS sounds good, wait until you hear True HD and DTS-HD on your favorite movie or concert video. If you want the cream of the crop, then get an A/V receiver with HDMI 1.3a Deep Color support and TrueHD and DTS HD audio decoding. These type of receivers start at around $800 and work up from there.
Step 3: Do you require external inputs and preamp outputs?
External multi-channel inputs are used for the purposes of connecting DVD-A and SACD and even some HD DVD and Blu-ray machines to play back high resolution audio. This can be cumbersome as it requires at least 6 RCA level interconnects between the player and receiver. While most $300 and up receivers today have 7.1 multi-channel inputs, many of them do NOT have preamp outputs. Preamp outputs are a necessity if you plan on pairing your new receiver with a more powerful external amplifier. This is usually a good idea when mating a receiver with low impedance, low efficiency speaker systems. If somewhere down the road you plan on eventually purchasing an external amp for this purpose and you are choosing between two receivers both of which have preamp outputs and inputs and the basic features you need, buy the cheaper receiver. Separate multi-channel amps usually have more power than even the best receivers on the market. Don't assume even a reasonably costly receiver will have preamp outputs. Always check the back panel. We were quite surprised that Denon didn't include this feature on their excellent AVR-2308CI A/V Receiver which retails for $850.
Examples: Denon AVR-3808CI, Yamaha RX-V1800
Step 4: Do you need multi zone functionality?
If you plan on routing speakers throughout the house for multi zone audio, you need to make sure the receiver you select has such capabilities. Most receivers in the $500 and up price range offer at least one additional zone of audio. If this is an important feature to you, it's a good idea to choose a model that allows you to use some of the internal amplifiers of the receiver for this functionality. That way if you buy an audiophile power amp to use on your main speakers, you don't have to let the amplifiers in your receiver go to waste. Some of the best multi zone receivers we've tested have been from Denon and Yamaha (model RX-V661 and up). We especially like these because they allow you to reassign at least 4 channels to Zones 2 and 3.
Examples: Denon AVR-2308CI, Yamaha RX-V861, Marantz SR4002 (and up)
Step 5: How much power do you need?
Are you party animal that likes to crank music at ear bleeding levels to impress your friends and really get everyone moving? If so, you will need a receiver with a hefty power supply - especially if you are running a multi-channel system in a largish room (over 3,000 ft^3). If your speakers are 4-ohm rated and have low sensitivity (<89 dB @ 1 watt), we recommend selecting a more powerful receiver that is rated to handle this. It's usually a safe bet that when buying a THX Ultra2 certified receiver, the power supply is up to the challenge. As a good rule of thumb, if a receiver has some heft to it (40lbs or greater) it will usually be robust enough to pump out some serious power. Onkyo has the lowest priced THX Ultra2 A/V receiver on the market – the TX-SR805 and it has quite a meaty amp section but it lacks some of the bells and whistles of its competitors. If you are looking for a bare bones HDMI-enabled powerhouse, this is a solid recommendation, otherwise expect to pay a little more to get a receiver with better upscaling features and audio streaming. Bottom line is if you like to listen to music LOUD, don't skimp on power. Alternatively, if it's not in your budget to buy the more powerful receiver, at least choose one with preamp outputs so that down the road you can connect a more powerful external power amplifier. With the price of quality multi-channel amps from the likes of Emotiva (IE. their new XPA-2 and XPA-5 amplifiers) being priced as low as mid level receivers, power has never been more affordable. Be sure to check out our detailed measurements and analysis sections of our A/V Receiver reviews to see just how well they stack up when being put through our vigorous testing procedures.
Recommended Reading: The ACD Amplifier Test, Product Managing Receiver Platforms
Examples: Marantz SR8002, Yamaha RX-Z11, Denon AVR-5308CI
Step 6: Do you need advanced bass management features?
In most cases the typical 80Hz global crossover setting and one subwoofer output will satisfy more users. However, more advanced users will prefer variable crossover settings per channel group and multiple independent subwoofer outputs. For the more advanced user, we suggest digging deeper to ensure that your receiver of choice truly does provide you the flexibility of connecting more than one subwoofer that has independent level and distance trims and will also give you the option of routing LFE and/or bass from all speakers set to 'Small'. There are several processors on the market that simply parallel out the main subwoofer output which limits your setup options. We have found Denon to be the leader in bass management flexibility but lately Yamaha, Onkyo and Marantz are catching up and offering multiple crossover selection per speaker groups, sub out with main speakers set to 'Large', and multiple subwoofer outputs, etc. Recommended Reading: A Guide to Connecting Multiple Subwoofers
Examples: Denon AVR-4308CI, Yamaha RX-Z11, Marantz SR8002
Step 6: Do you need advanced bass management features?
n most cases the typical 80Hz global crossover setting and one subwoofer output will satisfy more users. However, more advanced users will prefer variable crossover settings per channel group and multiple independent subwoofer outputs. For the more advanced user, we suggest digging deeper to ensure that your receiver of choice truly does provide you the flexibility of connecting more than one subwoofer that has independent level and distance trims and will also give you the option of routing LFE and/or bass from all speakers set to 'Small'. There are several processors on the market that simply parallel out the main subwoofer output which limits your setup options. We have found Denon to be the leader in bass management flexibility but lately Yamaha, Onkyo and Marantz are catching up and offering multiple crossover selection per speaker groups, sub out with main speakers set to 'Large', and multiple subwoofer outputs, etc. Recommended Reading: A Guide to Connecting Multiple Subwoofers
Examples: Denon AVR-4308CI, Yamaha RX-Z11, Marantz SR8002
Step 7: Bonus Features - the icing on the cake
Ok you've got all of the core features needed for a good home theater. Now it's time to put the icing on the cake. Let's talk about bonus features.
Video Processing If you're connecting older 480i equipment such as a Laserdisc player or (gasp) a VCR, you may want to select a receiver with video processing and upscaling. It's especially convenient to have a receiver upscale all of your video sources to HDMI. Keep in mind however that no matter how good the video processing capabilities are on a receiver, they will frequently do a worse job of scaling and upconverting than a dedicated HDMI enabled DVD player. Because of this, upscaling features built into a receiver are mostly useful for older analog video sources. Keep a mindful eye on our HQV test results in our receiver reviews to determine just how well a particular receiver does these duties.
Auto Set-up and Equalization These systems are usually a mixed blessing and almost never get all of the settings correct. But, the better ones can get you close and certainly all of them are better than not attempting to calibrate your system at all. Some companies such as Yamaha and Pioneer have their own auto setup systems called YPAO and MCAA, respectively. These generally do a good job of setting speaker level and distance, but we've found Audyssey to be a cut above the rest in getting your system to sound its best. Audyssey MultEQ can be found on receivers from Denon and Marantz as well as a handful of high-end processors.
Examples: Denon AVR-4308CI, Onkyo TX-SR875, Yamaha RX-V3800, Marantz SR8002
XM Radio and Network Streaming If you love the convenience of nearly infinite music channels and talk show selections and can stomach the massive amount of audio compression, than you may want to select a receiver with a built in XM tuner. If not, you can always add an outboard tuner in the future for around $100 or so.
Network streaming is really starting to take off in receivers and we really like what Yamaha has done here, especially if you are a MusicCAST owner. Denon has some nifty capabilities here as well and if you want music distributed wirelessly throughout your house, receivers from these guys are some of the top contenders.
Examples: Yamaha RX-V3800, Denon AVR-3808CI
Conclusion
Well there you have it. As you can deduce from this article, it all boils down to what level of HDMI connectivity you desire when choosing a receiver. At this point, budget A/V receivers ($250-$500) with basic HDMI splitter/repeater functionality will get you bare bone options, limited power and multi zone features. Stepping up to $900 or more will start getting you receivers with the latest audio decoding, basic video upconversion features and multi-zone audio support. Spending upwards of $1900 will get you those heavy THX Ultra2 certified receivers that will play louder and cleaner in larger listening spaces and have all of the video processing features as well as multi-zone and streaming audio support. While there is no need to over-buy based on your needs, it's important to understand what features you need in order to make your home theater function to your level of expectations and provide years of hassle-free enjoyment. There are a lot of great choices out there so take your time, do the research and ALWAYS purchase from an authorized retailer that offers post sale product support. Shopping for the best price isn't always the best option but we'll leave that as a topic for another article.
Step 1: What video connections do you need?
Does your DVD player or cable/satellite receiver use HDMI? If so, you'll want to choose a receiver that has HDMI connectivity or you will have to bypass the receiver and go directly to your TV to get the best picture quality. Going HDMI also simplifies your connections so the back of your A/V rack doesn't wind up looking like mine pictured to the right :)
Most entry level displays only sport 1 or 2 HDMI inputs so it's usually a better idea to select an HDMI-enabled receiver. Remember HDMI is the only connection method the new high definition players (ie. HD DVD or Blu-ray) are allowed to use to send HD signals (>480p resolution) from the player to your display so don't settle for component video or lower resolution connection schemes. HDMI receivers have come way down in price and can be had as little as $249 so there is almost no excuse NOT to be buying an HDMI enabled receiver today. Although we haven't tested the latest round of Pioneer receivers, they seem to be the market leader in the $350-and-under price category and their new x18-series A/V receivers that debuted at CES 2008 look most impressive.
Step 2: What HDMI functionality do you need?
Not all HDMI receivers are created equally. It wasn't until recently that the latest version of HDMI (ver 1.3a) was supported by any hardware despite it was the "going forward" standard for 1080p Deep Color (12-bit) video and True-HD and DTS HD audio support. Only HDMI 1.3a can support all of the latest formats natively, but it doesn't mean you can't get by on the lower versions, especially if the price savings makes sense. If your display resolution is limited to 1080i then older versions of HDMI will work just fine. If you don't own a high definition DVD player but eventually plan to buy one down the road, make sure the receiver you choose has multi-channel audio support via HDMI so you can have the player send the lossless decoded high resolution PCM audio signal to the receiver for it to provide bass management and proper routing to your speakers. If you think Dolby Digital and DTS sounds good, wait until you hear True HD and DTS-HD on your favorite movie or concert video. If you want the cream of the crop, then get an A/V receiver with HDMI 1.3a Deep Color support and TrueHD and DTS HD audio decoding. These type of receivers start at around $800 and work up from there.
Step 3: Do you require external inputs and preamp outputs?
External multi-channel inputs are used for the purposes of connecting DVD-A and SACD and even some HD DVD and Blu-ray machines to play back high resolution audio. This can be cumbersome as it requires at least 6 RCA level interconnects between the player and receiver. While most $300 and up receivers today have 7.1 multi-channel inputs, many of them do NOT have preamp outputs. Preamp outputs are a necessity if you plan on pairing your new receiver with a more powerful external amplifier. This is usually a good idea when mating a receiver with low impedance, low efficiency speaker systems. If somewhere down the road you plan on eventually purchasing an external amp for this purpose and you are choosing between two receivers both of which have preamp outputs and inputs and the basic features you need, buy the cheaper receiver. Separate multi-channel amps usually have more power than even the best receivers on the market. Don't assume even a reasonably costly receiver will have preamp outputs. Always check the back panel. We were quite surprised that Denon didn't include this feature on their excellent AVR-2308CI A/V Receiver which retails for $850.
Examples: Denon AVR-3808CI, Yamaha RX-V1800
Step 4: Do you need multi zone functionality?
If you plan on routing speakers throughout the house for multi zone audio, you need to make sure the receiver you select has such capabilities. Most receivers in the $500 and up price range offer at least one additional zone of audio. If this is an important feature to you, it's a good idea to choose a model that allows you to use some of the internal amplifiers of the receiver for this functionality. That way if you buy an audiophile power amp to use on your main speakers, you don't have to let the amplifiers in your receiver go to waste. Some of the best multi zone receivers we've tested have been from Denon and Yamaha (model RX-V661 and up). We especially like these because they allow you to reassign at least 4 channels to Zones 2 and 3.
Examples: Denon AVR-2308CI, Yamaha RX-V861, Marantz SR4002 (and up)
Step 5: How much power do you need?
Are you party animal that likes to crank music at ear bleeding levels to impress your friends and really get everyone moving? If so, you will need a receiver with a hefty power supply - especially if you are running a multi-channel system in a largish room (over 3,000 ft^3). If your speakers are 4-ohm rated and have low sensitivity (<89 dB @ 1 watt), we recommend selecting a more powerful receiver that is rated to handle this. It's usually a safe bet that when buying a THX Ultra2 certified receiver, the power supply is up to the challenge. As a good rule of thumb, if a receiver has some heft to it (40lbs or greater) it will usually be robust enough to pump out some serious power. Onkyo has the lowest priced THX Ultra2 A/V receiver on the market – the TX-SR805 and it has quite a meaty amp section but it lacks some of the bells and whistles of its competitors. If you are looking for a bare bones HDMI-enabled powerhouse, this is a solid recommendation, otherwise expect to pay a little more to get a receiver with better upscaling features and audio streaming. Bottom line is if you like to listen to music LOUD, don't skimp on power. Alternatively, if it's not in your budget to buy the more powerful receiver, at least choose one with preamp outputs so that down the road you can connect a more powerful external power amplifier. With the price of quality multi-channel amps from the likes of Emotiva (IE. their new XPA-2 and XPA-5 amplifiers) being priced as low as mid level receivers, power has never been more affordable. Be sure to check out our detailed measurements and analysis sections of our A/V Receiver reviews to see just how well they stack up when being put through our vigorous testing procedures.
Recommended Reading: The ACD Amplifier Test, Product Managing Receiver Platforms
Examples: Marantz SR8002, Yamaha RX-Z11, Denon AVR-5308CI
Step 6: Do you need advanced bass management features?
In most cases the typical 80Hz global crossover setting and one subwoofer output will satisfy more users. However, more advanced users will prefer variable crossover settings per channel group and multiple independent subwoofer outputs. For the more advanced user, we suggest digging deeper to ensure that your receiver of choice truly does provide you the flexibility of connecting more than one subwoofer that has independent level and distance trims and will also give you the option of routing LFE and/or bass from all speakers set to 'Small'. There are several processors on the market that simply parallel out the main subwoofer output which limits your setup options. We have found Denon to be the leader in bass management flexibility but lately Yamaha, Onkyo and Marantz are catching up and offering multiple crossover selection per speaker groups, sub out with main speakers set to 'Large', and multiple subwoofer outputs, etc. Recommended Reading: A Guide to Connecting Multiple Subwoofers
Examples: Denon AVR-4308CI, Yamaha RX-Z11, Marantz SR8002
Step 6: Do you need advanced bass management features?
n most cases the typical 80Hz global crossover setting and one subwoofer output will satisfy more users. However, more advanced users will prefer variable crossover settings per channel group and multiple independent subwoofer outputs. For the more advanced user, we suggest digging deeper to ensure that your receiver of choice truly does provide you the flexibility of connecting more than one subwoofer that has independent level and distance trims and will also give you the option of routing LFE and/or bass from all speakers set to 'Small'. There are several processors on the market that simply parallel out the main subwoofer output which limits your setup options. We have found Denon to be the leader in bass management flexibility but lately Yamaha, Onkyo and Marantz are catching up and offering multiple crossover selection per speaker groups, sub out with main speakers set to 'Large', and multiple subwoofer outputs, etc. Recommended Reading: A Guide to Connecting Multiple Subwoofers
Examples: Denon AVR-4308CI, Yamaha RX-Z11, Marantz SR8002
Step 7: Bonus Features - the icing on the cake
Ok you've got all of the core features needed for a good home theater. Now it's time to put the icing on the cake. Let's talk about bonus features.
Video Processing If you're connecting older 480i equipment such as a Laserdisc player or (gasp) a VCR, you may want to select a receiver with video processing and upscaling. It's especially convenient to have a receiver upscale all of your video sources to HDMI. Keep in mind however that no matter how good the video processing capabilities are on a receiver, they will frequently do a worse job of scaling and upconverting than a dedicated HDMI enabled DVD player. Because of this, upscaling features built into a receiver are mostly useful for older analog video sources. Keep a mindful eye on our HQV test results in our receiver reviews to determine just how well a particular receiver does these duties.
Auto Set-up and Equalization These systems are usually a mixed blessing and almost never get all of the settings correct. But, the better ones can get you close and certainly all of them are better than not attempting to calibrate your system at all. Some companies such as Yamaha and Pioneer have their own auto setup systems called YPAO and MCAA, respectively. These generally do a good job of setting speaker level and distance, but we've found Audyssey to be a cut above the rest in getting your system to sound its best. Audyssey MultEQ can be found on receivers from Denon and Marantz as well as a handful of high-end processors.
Examples: Denon AVR-4308CI, Onkyo TX-SR875, Yamaha RX-V3800, Marantz SR8002
XM Radio and Network Streaming If you love the convenience of nearly infinite music channels and talk show selections and can stomach the massive amount of audio compression, than you may want to select a receiver with a built in XM tuner. If not, you can always add an outboard tuner in the future for around $100 or so.
Network streaming is really starting to take off in receivers and we really like what Yamaha has done here, especially if you are a MusicCAST owner. Denon has some nifty capabilities here as well and if you want music distributed wirelessly throughout your house, receivers from these guys are some of the top contenders.
Examples: Yamaha RX-V3800, Denon AVR-3808CI
Conclusion
Well there you have it. As you can deduce from this article, it all boils down to what level of HDMI connectivity you desire when choosing a receiver. At this point, budget A/V receivers ($250-$500) with basic HDMI splitter/repeater functionality will get you bare bone options, limited power and multi zone features. Stepping up to $900 or more will start getting you receivers with the latest audio decoding, basic video upconversion features and multi-zone audio support. Spending upwards of $1900 will get you those heavy THX Ultra2 certified receivers that will play louder and cleaner in larger listening spaces and have all of the video processing features as well as multi-zone and streaming audio support. While there is no need to over-buy based on your needs, it's important to understand what features you need in order to make your home theater function to your level of expectations and provide years of hassle-free enjoyment. There are a lot of great choices out there so take your time, do the research and ALWAYS purchase from an authorized retailer that offers post sale product support. Shopping for the best price isn't always the best option but we'll leave that as a topic for another article.
Selecting Speakers
(1) 2-way or a 3-way speaker
A 2-way speaker's crossover splits the frequency band into two ranges: bass frequencies go to the woofer, and treble frequencies go to the tweeter. In a 3-way system, the frequency band is divided into three ranges. The middle frequencies are sent to a third driver commonly referred to as the midrange. Because 3-way speakers require more room for the drivers, they're usually only seen in floor-standing models.
(2) Speaker Impedance
A speaker's impedance rating refers to the amount of electrical resistance it presents against current flowing from your amplifier or receiver's powered outputs. Though impedance actually fluctuates as the speaker reproduces different frequencies, manufacturers usually publish a single, average figure, known as nominal impedance. Most home speakers have a nominal impedance rating of 8 ohms; likewise, practically all home A/V receivers are designed to be stable when pushing an 8-ohm load. There are a number of higher-end receivers that are capable of handling a 4-ohm load (if you're not sure about your receiver, check the specs in your owner's manual). Speakers with significantly lower impedance (4 ohms or less) may cause problems with 8-ohm receivers by asking them to deliver more current than they are capable of producing.
When you drop from an 8-ohm to a 4-ohm load, you cut the electrical resistance in half, which usually causes your receiver to increase its total power output. Some people are tempted to mate their 8-ohm receivers with 4-ohm speakers, in order to get more wattage. It's wise to avoid this temptation, since it can lead to greater distortion, and cause the receiver to run hot or activate its protection circuitry and shut down.
(1) 2-way or a 3-way speaker
A 2-way speaker's crossover splits the frequency band into two ranges: bass frequencies go to the woofer, and treble frequencies go to the tweeter. In a 3-way system, the frequency band is divided into three ranges. The middle frequencies are sent to a third driver commonly referred to as the midrange. Because 3-way speakers require more room for the drivers, they're usually only seen in floor-standing models.
(2) Speaker Impedance
A speaker's impedance rating refers to the amount of electrical resistance it presents against current flowing from your amplifier or receiver's powered outputs. Though impedance actually fluctuates as the speaker reproduces different frequencies, manufacturers usually publish a single, average figure, known as nominal impedance. Most home speakers have a nominal impedance rating of 8 ohms; likewise, practically all home A/V receivers are designed to be stable when pushing an 8-ohm load. There are a number of higher-end receivers that are capable of handling a 4-ohm load (if you're not sure about your receiver, check the specs in your owner's manual). Speakers with significantly lower impedance (4 ohms or less) may cause problems with 8-ohm receivers by asking them to deliver more current than they are capable of producing.
When you drop from an 8-ohm to a 4-ohm load, you cut the electrical resistance in half, which usually causes your receiver to increase its total power output. Some people are tempted to mate their 8-ohm receivers with 4-ohm speakers, in order to get more wattage. It's wise to avoid this temptation, since it can lead to greater distortion, and cause the receiver to run hot or activate its protection circuitry and shut down.
HDMI
http://en.wikipedia.org/wiki/HDMIHDMI (High-Definition Multimedia Interface) is a compact audio/video interface for transmitting uncompressed digital data. HDMI follows the EIA/CEA-861 standards. HDMI supports, on a single cable, any uncompressed TV or PC video format, including standard, enhanced, and high-definition video; up to 8 channels of compressed or uncompressed digital audio; a Consumer Electronics Control (CEC) connection; and an Ethernet
data connection. The CEC allows HDMI devices to control each other when
necessary and allows the user to operate multiple devices with one remote control handset.Because HDMI is electrically compatible with the CEA-861 signals used by Digital Visual Interface (DVI), no signal conversion is necessary, nor is there a loss of video quality when a DVI-to-HDMI adapter is used. As an uncompressed CEA-861 connection, HDMI is independent of the various digital television standards used by individual devices, such as ATSC and DVB, as these are encapsulations of compressed MPEG
video streams (which can be decoded and output as an uncompressed video
stream on HDMI). The HDMI standard was not designed to include passing closed caption data (for example, subtitles) to the television for decoding.
As such, any closed caption stream has to be decoded and included as an
image in the video stream(s) prior to transmission over an HDMI cable
to be viewed on the DTV. This limits the caption style (even for digital
captions) to only that decoded at the source prior to HDMI
transmission. This also prevents closed captions when transmission over
HDMI is required for upconversion. For example, a DVD player sending an
upscaled 720p/1080i format via HDMI to an HDTV has no method to pass Closed Captioning data so that the HDTV can decode as there is no line 21 VBI in that format.
The standard Type A HDMI connector has 19 pins, and a higher resolution
version called Type B, has been defined, although it is not yet in
common use. Type B has 29 pins, allowing it to carry an expanded video
channel for use with high-resolution displays. Type-B is designed to
support resolutions higher than 1080p.
The HDMI specification defines the protocols, signals, electrical interfaces, and mechanical requirements of the standard. The maximum pixel clock rate for HDMI 1.0 was 165 MHz, which was sufficient for supporting 1080p and WUXGA (1,920×1,200) at 60 Hz. HDMI 1.3 increased that to 340 MHz, which allows for higher resolution (such as WQXGA, 2,560×1,600) across a single digital link.
An HDMI connection can either be single-link (type A/C) or dual-link
(type B) and can have a video pixel rate of 25 MHz to 340 MHz (for a
single-link connection) or 25 MHz to 680 MHz (for a dual-link
connection). Video formats with rates below 25 MHz (e.g., 13.5 MHz for
480i/NTSC) are transmitted using a pixel-repetition scheme.
What is difference between 5.1,6.1 and 7.1 surround sound system
Each number represents the total number of speakers in the surround sound system.