Select Cost Effective Sound Surround System or sound bars for TVs

4 October 2018

Most Smart TV allow a source device such as blue-ray player to be connected to a TV using HDMI cables and have the TV pass the 5.1 or 7.1  sound surround signal to a sound surround receiver/player using HDMI ARC or digital co-axial or optical SPDIF cables.  However,  not all sound surround receiver/player can receive such raw 5.1 or 7.1 sound surround signal.  This article will explain why.

 

 Why?

For the sound surround receiver/player to be able to receive the raw 5.1 or 7.1 Dolby surround sound,  the receiver/player must have processors that can process and decode the compressed digital  bit-stream audio signal sent by the TV.  The cheaper and common receiver/player usually do not have this built in  function.  They simply receive stereo or 2 channel signal and have a Digital Signal Processors (DSP) to convert the stereo into 5.1 or 7.1 surround sound.     It is not a true 5.1 or 7.1 but a simulated  surround sound.

Which is better,   True or Fake?

The commoners  would invariably say the true 5.1 or 7.1 system is better;  however,  it is understand that not all movies are producing or the content providers are providing true surround sound.  Then the next question is whether one should choose the more expensive set that use patented Dolby Prologic signal processor to decode the raw Dolby surround sound  or just any DSP processor that just produce simulated surround sound.

What is Dolby Prologic or DSP?

Dolby Pro Logic is a surround sound processing technology developed by Dolby Laboratories, designed to decode soundtracks encoded with Dolby Surround.  DSP is a  microprocessor that is often used to simulate sound surround.   Whether one should choose a more expensive sound surround system will depend on the design and the quality of the soundbars and more importantly,   the "taste" of the users.  Some claimed that DSP produced better sound effect than Dolby Prologic. Therefore,  it is always better for one to listen to the sound system as everyone’s “taste of sound”  is different.

Why so much Cost Difference?

One would notice that there are a lot of cost differences between the cheaper and the more  expensive audio receivers or soundbars.    Actually,  if one were to strip the set down to its bare bones,  one would notice that all of them have similar major components such as power amplifiers,  signal processors and control  except that the more expensive ones might use better components such as thyroid transformer instead of ordinary laminated iron core transformers.   The more expensive ones usually have  much higher music power for better sound quality at lower sound volume.

Can MiTV4 Provide 5.1 Surround Sound?

Most MiTV can provide 5.1 sound surround sound but only the ones with external sound bars have specifically mentioned that it can provide Digital Audio Atmos digital surround sound.   Most MiTV can only provide simulated or virtual  surround sound

A Cost Effective MiTV Sound Surround System

This article will examine some of the popular and cheaper soundbars that have been used for Xiaomi and other televisions.  Among them,  the most common one that has been sold well  is the 33” Xiaomi TV soundbar as shown attached. 

The other soundbars that have been sold well in China is the JY Audio soundbars that have similar or better specifications.  

 These soundbars are tabulated and compared here for information (Note: scroll table to the left to read).  Note that these cheap sound bars have only DSP simulated sound surround output.

	Xiaomi 33-inch	万音 JY A1S	万音 JY A9S
Price	CNY399	CNY218	CNY358
Power	15 Watts,  6 ohms	30W+30W RMS	80W
Sound Channel	ATS2825/TAS5731M DSP	DSP sound surround	DSPS/SRS sound surround
Frequency	50 Hz - 25000Hz (-10dB)	20 Hz - 20000 Hz	40 Hz -18000 Hz
Channel Separation		>=65 dB	>=60dB
Sound to Signal		>=75 dB	>=70dB
Idling Power		<=0.5 Watts	<=0.5 Watts
Speakers	8 speakers	8 Speakers	8 speakers
Built-in
Tweeter	2 Nos of 35 mm Dome		2 Nos 2"
All Frequencies		2 Nos  2.5"	2 Nos 3"
Sub Woofers	2 Nos of 65 mm sub-Woofers
Mid range	4 Nos of 70x55 mm passive	2 Nos passive radiator	4 Nos 3" Bass radiation
External Woofer		60 Watts Bluetooth or Cable	60 Watts Bluetooth or Cable
Input Output	1x Co-axial SPDIF 1xFiber SPDIF 1x Stereo RCA 1x Aux in	1 x Sub woofer out 1 x Co-axial SPDIF 1 x Audio input Bluetooth for most TV	1 x Sub woofer out 1 x Co-axial SPDIF 1 x Fiber SPDIF 1 x Audio input Bluetooth for most TV
USB Thumb		Yes	Yes
Card Reader		TF card	TF card
Bluetooth	4.2	4.2	4.2
Power Supply	16 Volt 2.5 A	220 Volts	DC 24 V 3 A
Casing	Plastic Material	Wood with metal surface control panel	Wood with metal surface control panel
Dimension	83 x 7.2 x 8.7 cm	100 x 7.5 x 6.5 cm	98 x 10.2 x 7.1 cm
Weight (kg)	1.925 kg	3.2 kg	3.14 kg
Accessories	Co-axial SPDIF cable Manual	3.5 mm RCA Co-axial SPDIF Infra-red Remote Control Manual	3.5 RCA Coaxial SPDIF Fiber SPDIF Infra-red Remote Control Manual
	https://news.znds.com/article/32629.html		https://cn.made-in-china.com/gongying/jyav2013-ZeYJzxuGvjWm.html
Speaker System (Click to enlarge pictures)
Input Output (Click to enlarge pictures)
Control Panel (Click to enlarge pictures)
Accessories (Click to enlarge pictures)
Pthers (Click to enlarge pictures)

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Xiaomi TV4 Audio Connection (ARC)

28 Sep 2018

https://tinyurl.com/ycba5gg5

1) Audio Connection Options

2) What if Audio Receivers don't have digital input?
3) What if Audio Receiver has only Digital Coaxial Input
4) What if the Receiver only has Toslink Optical connection?
5) What if the Audio Receiver only has Blue Tooth?
6) What if the Audio Receiver only has HDMI (ARC)?
7) How to connect HDMI(ARC), SPDIF and/or BlueTooth?
8) Can We use Ordinary 2 Wire RCA cable as SPDIF cable ?
9) No Sound Output for HDMI ARC Connection
10) Only Stereo Sound Heard
11) What if Everything failed to Work?
 
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Audio Connection Options for MiTV4

Xiaomi TV4 has no analogue audio output connections e.g  RCA A/V connection.  It has only a digital Co-axial SPDIF and a HDMI with ARC (Audio Return Channel) for audio connection.    It has also a Bluetooth 4.2 connection but not all audio receivers or sound boxes have such advanced facility.  This article will discuss the following type of sound connections in Xiaomi TV

1.  Co-axial SPDIF   

    a)  Use Co-axial SPDIF to RCA audio converter   
    b)  Direct connection using Co-axial SPDIF cables 
    c)  Use Co-axial SPDIF to optical SPDIF convert 

2.   Bluetooth

3.   HDMI ARC 

     a)  Direct connection using HDMI version 1.4 cable
     b)  Use HDMI ARC to co-axial/optical/RCA converter  

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What if Audio Receiver does not have HDMI ARC or Digital Inputs ?

These receivers would have only analogue stereo inputs using  RCA cable connection or 3.5 mm jacks.   As Xiaomi TV4 does not  have any analogy outputs,  one would need to use audio converter described here (link)

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What if Audio Receiver has only Digital Coaxial Input ?

The connection will be straightforward using a  digital audio coaxial cable which looks like ordinary RCA cable but of better quality for digital signal transmission as shown below

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What if the Audio Receiver only has Toslink Optical connection?

a)  A HDMI or SPDIF converter would be required.  The following shows a setup using TV's HDMI with ARC to connect to the Audio Receiver's Toslink Optical port using a HDMI converter.   

b)  If audio receiver has HDMI with ARC input,  just use a HDMI cable for direct connection to TV’s HDMI3 that has ARC.

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What if the Audio Receiver only has Blue Tooth?

The connection will be straightforward by pairing the Audio Receiver directly to the MiTV using Bluetooth 4.2

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What if the Audio Receiver only has HDMI (ARC)?

What is ARC?

ARC stands for Audio Return Channel.  ARC was introduced in 2009 and it is now a standard in most smart TV.   The operation will  require the use of devices and cabling system that comply with HDMI 1.4 and above. Using ARC,  one would not need to have additional audio cable  as ARC can  use some of  the HDMI internal cable for sound transmission.  Usually,  TV has only one HDMI with ARC and is always labelled accordingly.   Connection using non-ARC HDMI outlets will not produce any sound.

Why need HDMI ARC? 

SPDIF,  whether co-axial or otherwise,  supports  only up to Dolby 5.1 but does not support Dolby 7.1;  only HDMI can support Dolby 7.1.  Ordinary audio system and many TV soundbars/receivers that produce simulated surround  support only stereo.. However，most Xiaomi TV have only Dolby 5.1 except for  65" Xiaomi TV4.  It has an external soundbar that support Dolby Atmos,  which is an equivalent to  Dolby 7.1.

Connections Using ARC

ARC let users send sound from a source (output)  to a sink (input) through a HDMI cable .  In the case of  connection between a TV and a audio receiver,   the TV is sending audio signal to the audio receiver through ARC.  In the case of the a TV and a video player,  the video player will be sending the video signal to the TV and if the video player's HDMI output  has an ARC,  the TV can send audio signal to the video player or vice versa using the same HDMI cable.

 

Not all ARC transmissions are perfect.  Having established a proper connection does not mean the system will produce proper sound.   It will depend much  how the TV can decipher the content providers' signal information and send the correct signal to the audio receiver or video player.  Therefore,  it is possible that one can only hear stereo sound (2 channels) while playing video contents known to have Dolby 5.1 or 7.1 surround sound.

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How to connect HDMI(ARC), SPDIF and/or BlueTooth?

The sound connection is not plug and play.   It requires proper setting up in the TV and the devices such as soundbars and audio receivers

a)  TV and Receiver Settings for HDMI ARC or SPDIF

To connect up the HDMI ARC or the SPDIF cable for sound output,  one would have to activate the control setting on the TV so that  the TV will direct the sound output to the respective HDMI or SPDIF output. 

On MiTV4,  there are 4 possible settings in the Sound Output Section

1. "自带扬声器"   TV’s own speaker system with Stereo (most people use this option)

2.  "HDMI(ARC)"   Sound connection using HDMI cable through ARC outlet

3.  "SPDIF"   Sound connection using SPDIF coaxial cable

4.   "小米家庭音响"   Using  Xiaomi’s Home  Sound System connected through coaxial cable

Select 2 if one is using HDMI ARC output

If one selected S/PDIF,  one would also have to set the decoder to  "RAW DATA" so that the sound system will output 5.1 surround sound.  If one were to select the decoder to "PCM" as shown, only stereo or two channel sound will be heard.

After that One would also need to consult the manual or seek manufacturer's advice on how to set or activate the control setting of the audio receivers or video players so that they can receive audio signal through ARC or send video signal through the HDMI connection.

b) BlueTooth

Connecting the Bluetooth device is relatively easy.  All one has to do is to pair up the devices.  To pair up,  fire up [Setting] and select [Device and Bluetooth],  MiTV will search for available Bluetooth device in the room.  If the Bluetooth device does not show up,  try turning on the Bluetooth device as it may be switch off by default.

Testing

After having connected up all the cables and done with the setting,  one can download the various sound test files available from here for testing

FAQs 

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1.  Can We use Ordinary 2 Wire RCA cable as  SPDIF cable ?

The SPDIF cable or the Digital Audio Cable used for SPDIF sound transmission is actually a better designed co-axial cable that looks exactly identical to the ordinary 2 wire RCA cable we used to connect up analogue stereos in the olden days.  They all have a centre copper wire,  braided wire mesh,  external PVC shield and a RCA header as shown below

Therefore,  they should all give a working audio digital  signal although many users claimed the specially designed SPDIF cable is of better quality and hence,  providing a better working audio sound.

One can easily test if the cable is faulty just by measuring the the electrical continuity of the cable using a multi-meter.

If there is no sound when SPDIF cable is connected and before starting to complain,  

1.  Make sure that MiTV's sound output and the audio receiver's sound input is set properly to the correct setting as shown below. 

2.  Make sure one has plugged the cable in the right RCA socket using only a co-axial cable.

 .  The co-axial socket is the 2nd one on the right and next to TV aerial socket when one faces the TV.

3.  Turn up the volume as high as possible.  For some designs,  3/4 of full volume for the TV and the sound bar is not uncommon depending on the signal input and the quality of the cable.   For some reasons,  the SPDIF output from devices by specification is always lower than the  other kind of sound devices

souce:  https://en.wikipedia.org/wiki/S/PDIF...specifications

 

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2.  No Sound Output for HDMI ARC Connection

Please refer to this link for more information.

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3. Why Only Stereo Sound Heard

1.   Make sure that the setting in the TV and the Audio receiver have been set correctly  to HDMI ARC

2.   Try some other TV channels to find out if the TV is compatible to receive proper sound signal information  from the content provider. Sometimes,  the internet transmission might affect the transmission of ARC signals.

3.  Refer to this link for more assistance

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4.  What if Everything failed to Work?


If everything failed,  just connect the audio system using HDMI converter as shown in para 3 or the type as shown below.   May be the audio system does not accept the ARC connection.

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How Best One Can Trust Analysts’ Earning Estimates?

12 August 2018

One often hear this stock market slang during every earning seasons;  “The company has beaten or its earnings has exceeded consensus’s estimate with a surprise”.     This article will tell why this happens so often at the Walls Street.

Earning Surprises

 One could always find this kind of table in the web and very often,  the list of companies with “surprise” positive earnings is always longer than the negative earnings .

Why?

There is usually only one answer i.e. the Analysts have under-estimated the earning results. 

How could that happen?

Lets examine one of the earning summary report by Lippe Alpha Insight as shown below,  one will notice that the companies are always reporting negative EPS when they make preannouncements.   These preannouncements by the companies will affect the Analysts’ estimates as no Analyst has better knowledge about the operation  than the companies.

Could this Just Be a Coincident for Q3 2018?

FactSet,  an organization who provides  financial data and analytics for  investors,  has this chart in  their web page

 One can see that there is a consistent pattern for most companies to provide negative preannouncements.    Note that not all companies will make preannouncement but those who did,  always do it with a purpose to get better stock prices.

Is This Fair?

Obviously,  not fair to the investors.  But there are no hard rules for such  preannouncement.  Moreover,  the companies are said to provide the  estimates to their “best knowledge”.   The market is now so used to this pattern of reporting that Analysts and investors are comparing  which year the market has the most positive preannouncement issued by the companies. 

Should we be concerned?

Most investors have learnt  not to trust fully the Analysts’ earning reports.   However,  there are many investors still rely on the Analysts’ report to buy stocks particularly those investors who  go after “growth stocks” rather than “valuestocks”    If these investors were  not careful in sorting out the genuine and accurate  earning reports from the bad ones,  they can be taken by surprise and lose a lot of money.

What Should We do?

To protect our interest,  always take stock market reports especially the earning reports of the Analysts as reference and confirm the earnings with other form of market reports or other reports  from other companies.  Do not just trust the market report from one company or Analyst.   Read through the company’s financial statements especially try to decipher  how the company can get such good earnings.

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A Warning Sign for Stock Market?

1st August 2018

NASDAQ fell about 4% after reaching its all time high of 7,932 on 25 July 2018.   It may appear to many that this is just another rotational play where investors are selling away winning stocks and shifting their money from one segment of the market to another especially when NASDAQ has just reached its all time high.  There is nothing to worry about.

What’s Behind NASDAQ’s  Drastic Sell Off?

There are many reasons.   One of the reason is that the US investors were going more for  “growth” stocks which are subjected more to speculation as they are often  “fueled” by news of future earnings or growth.   The US investors has shifted their portfolios more to buying "growth" stocks rather than "value" stocks.

What is Growth and Value  Stocks ?

Growth and Value are two fundamental approaches  in stock investing.  Growth investors will buy companies or Growth stocks that offer strong earnings growth while Value investors will seek undervalued stocks or Value stocks that has good fundamentals.

How to know there is a Shift?

The shift can be seen from the following chart that compares the trend of S&P 500 Growth ETF( IVW) and the S&P 500 Value ETF (IVE).   The chart clearly shows that investors shifted from Value stocks to Growth stock after mid 2015.   The shift is more pronounce in the last leg between 2017 and 2018.

This shift has unfortunately created a market that is  extremely sensitive to news and prepared to respond rapidly.  When growth-stock investors become disappointed with a company, they would   dump  the company's stock and proceed to buy the next exciting company.  

On July 29, 2018,  almost all the growth stocks  like   Facebook,  Apple,  Amazon,  Netflix,  Google and Alphabet in NASDAQ and S&P that have been sold off .

 Are There Any Sign?

Analysts who tracked closely the “Value/Growth” ratio of the US market are showing us the following chart

With courtesy of the following article

The chart plotted the value/growth ratio of the US market in the last 10 years between 2008 and 2018.   It shows that the growth/value ratio,  last peaked around mid 2008,  peaked again recently with investors buying 4 times as much “growth” stocks than the “value” stocks.   A "near peak" occurred around mid 2015 (Point A above) 

Do We Need to Worry?

It is quite common to see market selling off especially when NASDAQ has just retreated  from its recently peak.   It is also common to see investors adjusting their portfolios,  rotating between one segment of the market to the next segment.  

However,  if we examine the above Growth/Value chart closely and compare the happenings to the DOW chart,  we can see that the peaks or near peaks of value/growth ratio occurred around the time when market took the plunge as shown in the following chart.

What the Market Was Telling Us?

On July 26, 2018,   Facebook had the biggest  single day loss of about USD$120 billions in US history.  Mark Zuckerberg lost more than USD$16 billion as a result.

S&P’s market cap shaved off around USD$2 Trillion since all time high in 2018.   The 5 big companies lost a total of USD$330 billions altogether since their highs.

 

S&P 500 lost $2 trillion in market cap since all-time high from CNBC.

In Conclusion

While it all appears fine with markets started to stabilise and even recovered some of its losses,  we mustn’t be too complacent with the market because

1.  The investors have shifted from value stock to growth stock  since mid 2015. This is especially so,  after Trump was elected to office in Jan 2007.  Unfortunately,  this shift has increased the risk of a market plunge as growth stocks are often fueled by speculation of future earnings and growth;

2.   Studies showed that the Grow/Value Ratio has again reached another peak since the last market plunge in 2008 about 10 years ago;

3.  The market experienced tremendous price shock on July 26,  2018.  It resulted big investors having to lose a lot of fund and money.   It is not known how well  they  could handle this market shock.

Disclaimer:  This article is for information and  educational purposes.   Readers are advised to  conduct their own research and study to make their  own investment decisions.

References
tinyrul : https://tinyurl.com/ycfewutf

Are Stock Markets Approaching the “Valley of Death”?

26 July 2018

Many investors are watching the yield curves of US Treasury carefully.  The trend is worrying as the yield curve has flattened over the recent months,  approaching the triggering point where another economy recession is in the making.

What is Yield Curves?

Simply,  it is a line that plots the interest rates (which is also the “Yield” when it is referred to Bonds or Treasury Notes).  When interest rate rises,  so will the yield of the Treasure Bonds or Notes.  Normally,  the yield is lower for the shorter maturity bonds or notes and higher for longer maturity type.

More about yield curve in here

Why Worry About Yield Curve?

Government Treasury Bonds or Notes are known to be investment safe heavens because they are  “backed” by the Government.  During good times,  investors will buy and keep Bonds especially those with longer maturity such as the 30-year bonds because they are cheaper and have higher yields.  During bad times,  investors will get worried about the economy.  They will sell away their Bonds or Notes even those with shorter maturity such as the 2-year or 10-year Notes.   As a result,  the yields of those with shorter maturity will rise.  The yield curve will gradually flattened and eventually,  inverted if the economy is getting worse.  Yield curves are often used to predict the condition of an economy.

 

Present Yield Curve

The present yield curve has been gradually flattened  since Trump took office from end 2016.  During this period,  Federal Interest Rate rose from 5 times from 0.75% to now 2.0 %.

Should the rate continue to rise,   one would expect the yield curve to be flattened further.

Trump Worried About Fed Rate Hikes

Trump openly expressed concerns about the Federal Rate Hikes recently as Fed mentioned that there would be 2 more rate hikes before the end of the year.

 

https://www.scribd.com/document/384820045/Trump-Worries-That-Fed-Will-Raise-Rates-Two-More-Times-This-Year-White-House-Official

As a result,  the implied probability of the rate hike in Aug 2018 collapsed and dropped from over 90% to almost nothing.  DOW  celebrated the  last 3 days with a rebounce of over 300 points.  

 Why Fed Has to Hike Rates and Unwind its Balance Sheet

1.   Fed hike rates because it sees the US inflation rates have been rising over the last 12 months from 1.7% in Jan 2017  to almost 3% in Jun 2018;

2.  Fed also sees the market is flooded with liquidity and this caused market growth to almost stagnant with Long Term Corporate Debt rising almost 50% since they introduced QE;  meaning,  more and more companies are borrowing money to finance their business with little or no future growth registered.    Fed has to reduce the risk and pull out the liquidity by shrinking its  balance sheet.

 Going Ahead

1. Where are we?

This 30-year to 10-year yield index clearly shows that the market is ready to approach the phase that  will trigger another economy recession;

2.  Will US be able to arrest the problems and reverse the situation?

Fed and the Authority including Trump are obviously  aware of the economy slow down and do what they can to arrest the problem.  They cut tax  and introduce Job Acts which are expected to add another USD 1.5 Trillion to the present debt of  more than USD 21.0 Trillions.

https://www.scribd.com/document/384823222/Tax-Cuts-and-Jobs-Act-Will-Cost-1-5-Trillion-Committee-for-a-Responsible-Federal-Budget

The tax cut and Job Acts are able to help the economy but it is unlikely to change significantly the fundamental conditions of the present US economy which is fueled by debts.

A Trade War was also planned  to boost the US's export and reduce the US's deficit so as to arrest the rising debts;  however,   many Analysts are skeptical about the result and some said the US economy might not survive the trade war.   This is because imposing tariff  in a trade war is equivalent to raising taxes on the goods.

Unless there is a change fundamentally to improve the economy,  it is unlikely that above measures will arrest the problems and save the economy.

Can the US economy survive a trade war? from CNBC.

In Conclusion

We are now approaching the "Valley of Death".

Disclaimer:  This article is for information and  educational purposes.   Readers are advised to  conduct their own research and study to make their  own investment decisions.

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Reference
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Wall Mounting LCD/LED TV

26 July 2018

https://tinyurl.com/y8s329mb

It is common for vendors to include installation cost when buying TVs from the Supermarket.  It is also common for us to buy TV online because it is always cheaper.   However,  many online vendors are just importers looking for quick sale.  They do not often include cost of installation which may cost around SGD$100.    One could save this cost if one could DIY the installation.

What's Needed?

To wall mount TV,  one must have at least the following

1.  An impact drill and drill bit for drilling holes in the wall;
2.  The right size of TV wall mounting bracket
3.  Screw driver
4.  A water level gauge
5.  4 Nos Mounting screws to match TV's mounting hole;  usually M6 or M8 screw
6.  4 Nos of 6 mm x 80 mm masonry screw and 4 Nos raw plug.  

How to Install and Mount the TV?

The following video gives good details about how to install and mount the TV.

 What are the other Advice?

 In addition to follow the steps shown in the video,  it is good to take note of the following:

1.  Purchase a metal or stud detector.  This is advisable as most apartments nowadays have concealed water and electricity pipes in the wall.   Use this detector to locate the concealed pipes and live wire before starting any wall drilling.   This metal detector is available from any hardware store or online for less than SDG$20/=

2.  For large TV more than 40",  it is advisable to get a helper to mount the TV.   Note that Xiaomi TV4 such as the 55" TV is  very thin.  The screens can be easily damaged if they are not handled properly

3.  Make sure the mounting screws are of the correct sizes.  The mountings of Xiaomi TV should comply with VESA standard in which the screw sizes,  distances and depth of mounting holes should be of standard size.

VESA Standard

If the TV is complying to VESA standard,  one could use the following specification to determine the size of screws ,  depths and the width of the mounting holes

The distance between the holes,  the number of holes and the other details are also standard for various sizes of TV as shown below

MiTV Mountings

MiTV's Mountings do not quite follow strictly the VESA standard.  Various sizes have different holes and dimension.   Some models of the same type  also have difference dimensions.   It will be hard to find the correct wall mounting without knowing the actual specification.  One could try to use universal wall mounts that are designed specially for TVs that does not follow the VESA standard.  These universal mounts usually come with various type of mounting holes and some are adjustable to suit various size of TV mounting holes.

How to Remove Old Television from the Wall?

It is always good to get a helper to dismount the TV from the wall as some designs of the older TV bracket might have nasty hooking method.   For most TV mount of the bracket type as shown,   just lift up the TV from the hook and remove the TV.

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