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Monoprice RedMere HDMI cables general discussion

C

Crow550

Platinum Member
Check them out here: http://www.monoprice.com/products/subdepartment.asp?c_id=102&cp_id=10255

http://www.monoprice.com/home/news_detail.asp?news_id=109&s_keyword=

201110we_redmere_011-thumb-300x286-2738.jpg

RedMere-HDMI.jpg


They claim no signal loss and no need for signal boosters (equalizers) up to 100ft(maybe even longer too).

Title Edited
AV&HT Moderator YOyoYOhowsDAjello
 
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on a related note, I wonder if there will a time when we can "blue tooth" all the devices and get rid of all cables once and for all.
 
Damnit. I bought a 'cable saver' last week because I needed something flexible but I would have much preferred something longer like this
 
thats pretty sweet, ill def get them next time i need cables. currently i still have a bunch from a HOT DEAL where i got 10 6 footers for 12$.
 
Binarycow said:
on a related note, I wonder if there will a time when we can "blue tooth" all the devices and get rid of all cables once and for all.
Click to expand...

This would be great but blue tooth barely works for what its intended for already... we got a ways to go before effective wireless home theaters...
 
Hmmm, I'll probably pick one of these up in a few weeks - I'll be subletting my friend's apartment and my PC will be in the second bedroom that shares a wall with the living room where the TV is. Too bad I can't drill a hole in the wall...hmph.
 
Monoprice has updated there HDMI info page. According to it RedMere cables will not need any signal boosters and will work up to 131ft. Sounds awesome.

HDMI® Cables - Introducing RedMere®

RedMere® cables have been recently introduced to the Monoprice catalog of HDMI® Cables. RedMere® cables have a small chip in the HDMI® connector, which boosts the performance of the cable. The significant factor about RedMere® cables is that they break the rules above about cable gauge (AWG) and maximum lengths. RedMere® cables can be much thinner than normal HDMI® Cables and can reliably handle High Speed (10.2 Gbps) signals to much greater lengths. HDMI® Cables with RedMere® chips can handle High Speed signals to a maximum of 40 meters (131 feet)!
Click to expand...

http://www.monoprice.com/home/home.asp?pn=help&idx=12
 
Active cables like this are device powered and not all devices will provide enough power to power the cables. The chips used are not power hogs but using chips like this without external power is abusing the original spec so early HDMI devices may not work. There is nothing special about the cables chips, they have been around for years, the reason other manufacturers never did it is because of the questionable power source.

If you are interested in the chips like this , here is one, been out since 2007.
http://www.maxim-ic.com/datasheet/index.mvp/id/5427

I asked someone in the know about the power usage vs what is supplied. The spec is limited to 50ma, these chips consume at the minimum 75ma. The voltage they are taking the power from is used to signal the endpoint that there is a device present, without that voltage you could see problems of device not detected or other flaky response. I also have to wonder how overloading the power supply will effect the lifespan of the regulators supplying the current. These cables are not recommended by HDMI org. They recommend getting cables that use an external power source.
 
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Modelworks said:
Active cables like this are device powered and not all devices will provide enough power to power the cables. The chips used are not power hogs but using chips like this without external power is abusing the original spec so early HDMI devices may not work. There is nothing special about the cables chips, they have been around for years, the reason other manufacturers never did it is because of the questionable power source.

If you are interested in the chips like this , here is one, been out since 2007.
http://www.maxim-ic.com/datasheet/index.mvp/id/5427

I asked someone in the know about the power usage vs what is supplied. The spec is limited to 50ma, these chips consume at the minimum 75ma. The voltage they are taking the power from is used to signal the endpoint that there is a device present, without that voltage you could see problems of device not detected or other flaky response. I also have to wonder how overloading the power supply will effect the lifespan of the regulators supplying the current. These cables are not recommended by HDMI org. They recommend getting cables that use an external power source.
Click to expand...

Can you or your friend link some sources please?

I checked the RedMere site on compliance: http://www.redmere.com/business/compliance.php

On the chip tech: http://en.redmere.com/technology.php#MagnifEye

Look at page 6 of this: http://en.redmere.com/download.php?file=102

Power Requirements of Active Equalization

A further challenge in supplying any kind of equalization is delivering power to the
equalization circuit. HDMI only allows for 5mA current consumption from its 5V power
supply. This 5mA limit makes it difficult to deliver effective equalization solutions for
any useful range of cable structures, thicknesses, lengths and speeds.

With this limitation in mind, power can be harvested from the sink device, e.g. TV or
monitor, through the output driver of the equalizer circuit. This power supply is then used
to supply the equalizer and subsequent circuits needed to drive the data through the
output driver. Another aid in dealing with low power is to use small circuit devices. The
usual limitation with this approach is that matching in these small devices deteriorates,
which in itself would severely limit the performance of the channel. This problem is
removed however with advanced silicon design techniques in the design of these circuits.
With these power-related additions, no external power supply is required for the
equalization and the 5mA HDMI limit is adhered to with the active equalizer. This
ensures that the approach does not violate the standards compliance requirements of the
HDMI standard.
Click to expand...
 
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Redmere said:
Power Requirements of Active Equalization

A further challenge in supplying any kind of equalization is delivering power to the
equalization circuit. HDMI only allows for 5mA current consumption from its 5V power
supply. This 5mA limit makes it difficult to deliver effective equalization solutions for
any useful range of cable structures, thicknesses, lengths and speeds.

With this limitation in mind, power can be harvested from the sink device, e.g. TV or
monitor, through the output driver of the equalizer circuit. This power supply is then used
to supply the equalizer and subsequent circuits needed to drive the data through the
output driver. Another aid in dealing with low power is to use small circuit devices. The
usual limitation with this approach is that matching in these small devices deteriorates,
which in itself would severely limit the performance of the channel. This problem is
removed however with advanced silicon design techniques in the design of these circuits.
With these power-related additions, no external power supply is required for the
equalization and the 5mA HDMI limit is adhered to with the active equalizer. This
ensures that the approach does not violate the standards compliance requirements of the
HDMI standard.
Click to expand...

Wow, a lot of mumbo jumbo in there 🙂

I particularly like "power can be harvested from the sink device". How do you harvest power from something that is not supplying any power?
 
Drako said:
Wow, a lot of mumbo jumbo in there 🙂

I particularly like "power can be harvested from the sink device". How do you harvest power from something that is not supplying any power?
Click to expand...

That's all I could really find at this time. Still browsing around. However it seems to be HDMI complaint.

I also e-mailed RedMere & Monoprice about this.
 
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Crow550 said:
Can you or your friend link some sources please?
Click to expand...

I went back and read the specs myself, the +5V line is limited to 50ma so their stated 5ma is wrong. It is for the purpose of the EDID line that displays use to tell other devices what formats they support, if they can do HDCP , etc. Depending on how the device implements that regulator chip it will either shut off the current when it goes beyond 50ma or it will try to source the extra amount and eventually harm the lifespan of the chip. If redmere wanted to do it right they would have added a power plug to either end of the cable and an external adapter, but that already exist.


The redmere cables are not HDMI compliant when used like they are in that cable. The spec does not allow for powering external devices from the 5V line.

This is just like circuits that are powered off the parallel or serial ports on computers, the interface was not designed with that in mind and it may or may not work.


From HDMI.org
http://www.hdmi.org/installers/longcablelengths.aspx
Beware products that draw power from the +5V power line. Although these may work in certain applications, different components draw varying amount of power from that line to communicate with each other. A cable that draws power from the HDMI cable may fail when components and the active components in the cable or external booster are all drawing from the same source.
Click to expand...
 
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Hi everyone,

Just wanted to chime in with some details regarding the our upcoming HDMI cables with Redmere technology.

HDMI only allows for 5mA current consumption from its 5V power
supply. This 5mA limit makes it difficult to deliver effective equalization solutions for
any useful range of cable structures, thicknesses, lengths and speeds.
With this limitation in mind, power can be harvested from the sink device, e.g. TV or
monitor, through the output driver of the equalizer circuit. This power supply is then used
to supply the equalizer and subsequent circuits needed to drive the data through the
output driver. Another aid in dealing with low power is to use small circuit devices. The
usual limitation with this approach is that matching in these small devices deteriorates,
which in itself would severely limit the performance of the channel. This problem is
removed however with advanced silicon design techniques in the design of these circuits.
With these power-related additions, no external power supply is required for the
equalization and the 5mA HDMI limit is adhered to with the active equalizer. This
ensures that the approach does not violate the standards compliance requirements of the
HDMI standard.

Using Equalization to Boost Cable Performance

In order to address the above-mentioned performance limitations, the ideal solution
would have in-cable equalization capable of up to 25dBs of boost. Such equalization
should have a variety of boost characteristics in order to cancel various losses in a wide
spectrum of cable gauges, lengths and speeds. As already discussed, not only can
individual cables from the same batch show different loss characteristics but individual
channels within each cable can also widely vary. A solution whereby each channel has an
equalizer that can be individually tuned or programmed at production would solve all
performance issues.

The function of the equalizer can be described as follows: As the magnitude response of a
system rolls off at higher frequencies, the equalizer counteracts this phenomenon by
having a magnitude response that will increase with increasing frequency. There are
typically two options for equalization – passive and active.

Passive equalization techniques suffer from a number of critical performance limitations
which restrict their application. Passive equalization requires an inventory of passive
elements which are costly to maintain for manufacture. The passive circuit has no gain –
in fact it suppresses the signal. This will result in a reduced signal to noise ratio at the
output of the cable. Impedance matching can also be an issue as the passive elements of
the circuit will compromise the 50ohm matching requirements, causing potential
undesirable reflections in the cable.

Another significant drawback with a passive equalizer scheme is that it is difficult to
construct the complex boost characteristics required by the 3.4Gbps channel using
passive techniques. Consider when a cascade of poles and zeros is used to
approximate a boost characteristic of 13dB/decade. This is a complex scenario in that for
the equalizer to realize this characteristic would require a large number of poles and
zeros. Each pole and zero requires additional passive elements. Beyond only a small
number of poles and zeros the passive equalizer circuit becomes cumbersome and costly.

Most importantly however the passive equalizer is not adaptive. The circuit has no way of
altering its performance based on the characteristics of the cable in its input path. It has a
fixed amount of equalization and needs to be redesigned to function optimally for various
cable gauges, lengths and frequencies, and will never be adaptable on a per channel basis.
Active cable equalization techniques overcome all of these performance limitations. An
active equalizer has signal gain so that signal swings are amplified and do not suffer from
the associated losses and distortions. Impedance matching is overcome as correct
terminations can be applied on the input and output of the equalizer, resulting in lower
reflections within the cable. With a programmable silicon active equalizer embedded in
the cable, it is possible to construct large sets of poles and zeros cheaply and then tune
them to cater for a large range of cable responses.

This allows for a whole family of
different equalizer boost settings which are tunable on a per channel basis.

And Redmere is one of HDMI.orgs registered adopters as well, ensuring HDMI compliancy.

http://www.hdmi.org/learningcenter/adopters_founders.aspx#R
 
Monoprice said:
Hi everyone,

Just wanted to chime in with some details regarding the our upcoming HDMI cables with Redmere technology.
Click to expand...


Cut and paste from the Redmere site, didn't even bother to read the whole thread and still repeating the mistake of 5ma when it is 50ma.
 
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Sorry for the confusion everyone, actually our new Redmere HDMI cables are based on their latest PRA series Chipset. Like poster Modelworks mentioned in his previous posts, older generation chipsets like the RM1689 have been around since 2007, and have never been the most reliable solutions due to power limitations already mentioned. However, the modules themselves have changed a great deal since then and are capable of generating ATC Testing compliant cables. While I cannot go into operating details, I can tell you each module contains a chipset in a particular model family but each module itself is different as they are designed per cable length/application. Unfortunately due to confidentiality agreements I cannot specify details of the modules except for basic features. I will happily try and get clarification on any features or specifications that may be erroneous and reach out to HDMI.org or Redmere directly to clear up any of the possible issues.

Not only will we be introducing these latest generation low power modules that are < 50ma peak over the +5V channel per HDMI.org standards, we will also introduce ultra-high bandwidth modules supporting transfer speeds of up to 18Gbps. We do understand how touchy HDMI can be and there is no guarantee over long lengths exceeding 20 meters (around 65 feet) that the cable will always work as device manufactures don&#8217;t exactly design their products to the same specification, it can be frustrating at times but we do offer a 30 day return policy giving you ample time to test compatibility with your equipment. If you have any specific details you would like addressed, please let us know! We definitely appreciate all the feedback, and look forward to being an active member of your community.

Pricing for our Redmere Active cables will be around &#8211;

6 Foot @ $13.23

With various lengths all the way up to

60 Feet @ $72.00
 
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