In 2020, a media player is a redundant piece of equipment – if one has a appropriate network attached storage (NAS) server, the topic of next week’s post. Yet, it is its own separate topic because of three different, but related, challenges.
First, people do not understand humankind’s physical capabilities and limitations when it comes to normal seeing and hearing. Normal is the operative term here. Visual impairment will be discussed in its own weblog post: 2020-11-24. Hearing impairment will be the topic one week later: 2020-12-01.
Second, this limited understanding results in the purchase of peripherals, such as speakers and screens, that don’t match user needs. On top of this they will purchase media players or a NAS that are neither suitable nor likeable, from hardware/ software/ operational perspectives.
Third, people tend to make evolutionary, rather than revolutionary, purchasing decisions. They replace components, rather than rethinking the components they need. For example, they may be used to having a television set with an attached recorder for watching video and the accompanying audio content. At the same time, they will have a separate stereo system for reproducing music. Unfortunately, such thinking belongs back in the twentieth century, not the current century that is already more than 20% over.
When we (along with the rest of our local community) updated to broadband, effectively at the beginning of 2019, a number of cable television options were available as a package for about NOK 1 500 a month, with an internet speed of 500 Mbits/s. We declined to have this, and opted for a 50 Mbit/s speed, without cable television, for NOK 600 a month.
A main purpose of a media player is to take content either from an online-source or from a file stored somewhere, including personal handheld devices aka mobile phones, and to send the video content to some form of display/ projector, and the audio content to some form of loudspeaker/ headset. Handheld devices, can be used to control the media player. In essence, they are the 21st century’s remote control.
If people use a particular processor or operating system on their laptop or desktop machine, they will often want to use the same one on their media player. This is understandable, for it keeps them in their comfort zone.
Unfortunately, there are still hardware issues with respect to Intel processors, and – to a lesser degree – those of Advanced Micro Devices (AMD). This design flaw has been known since the beginning of 2018. People are encouraged to use ARM or AMD, rather than Intel processors where these are available. Apple, has recently abandoned Intel and gone over to ARM.
An aside: In 1990 ARM stood for Advanced RISC Machines, a company that started life in 1983 as Acorn RISC Machine, referring to the processor in the Acorn Archimedes computer, used by many schools. From 1998 ARM is simply Arm, not an abbreviation for anything.
Yet, for example, Windows users will often complain about the bloatware on Windows 10, but not do anything about it, either on their personal computer, or a media player. More specifically, they will seldom explore open-source software, including operating systems, as an alternative to the commercial products on offer.
At Cliff Cottage on 2019-04-11, an Asus PN 40 computer was ordered to replace an Asus Tinkerboard, similar to a Raspberry Pi (RPi), as a media player. It is equipped with an Intel Celeron processor, effectively demonstrating that I don’t follow my own advice. The hardware on the PN 40 is more than adequate for its role as a media player. It includes: a Western Digital Green 3D Nand M.2 2280 triple-level cell (TLC) solid-state drive (SSD) providing 240 GB; and, 2 x 4 = 8 GB matched Corsair Vengeance SO DD4 2400 MHz, CL16, 1.2 V DC, non-buffered, non-EEC RAM cards.
The device is low-powered and fanless, but capable of playing videos and music stored on Mothership, the family Network Attached Storage (NAS) server. It is equipped with a LibreELEC = Libre Embedded Linux Entertainment Center, operating system, described as “just enough Linux for Kodi“, an open-source media player, which is also installed.
If the purchase of a media player had been delayed to now (2020-10) it would have been an Asus PN 50, a similar, low power (read: minimal watts), yet a machine with adequate processing throughput. It would be equipped with an AMD Ryzen 3 processor. At the time of purchase, these were not available in Norway. Cliff Cottage now has an Asus PN 50 with a Ryzen 7 4700U processor, but it is being used for other tasks.
An even cheaper, but perfectly adequate, media player can be constructed from a RPi 4 B with anywhere from 1 to 8 GB of RAM. Because of its tendency to overheat, cooling must be used. One approach is to place the RPi in a Flirc case.
Vision
The human eye is not impressive. For eyes to write home about, examine assorted species of mantis shrimp.
Boomers probably experienced cathode-ray tube black and white televisions in the 1950s with PAL providing 625 lines, and NTSC providing 525 lines, essentially 480i (interlaced). This was then upgraded to colour television in the 1960s.
In the 1990s, flat-screen televisions emerged and now dominate. High definition (HD) = 1920 x 1080 pixel resolution, became a standard with the high definition multimedia interface (HDMI), defined in 2002. A decade later, in 2012, ultra high definition (UHD) = 3840 x 2160, four times the pixel count of HD (hence, 4K) was defined, and in 2020, is now dominant.
Early flat-screen televisions used plasma technology, then came liquid crystal displays (LCD) that needed backlighting. LCD usually refers to the use of cold cathode fluorescent lamps (CCFL) for backlighting. LED screens are LCDs that use light emitting diodes (LED) for backlighting. This technology is actively used today. Organic light emitting diode (OLED) technology uses diodes to generate colour and light, like plasma screens, but they are smaller and thinner than LED-lit panels, and are capable of producing the best black levels available (highest contrast ratios). OLED screens are considerably more expensive than other screens.
A television in 2020 has 4K resolution. HD is out of date, while 8K is not only too expensive, it lacks content. A video refresh rate of 60 Hz is acceptable, 120 Hz is better, while gamers maintain that 144 Hz is best. Yes, this is a real consideration, if one is to avoid having multiple screens in a household. High dynamic range (HDR) refers to a colour standard that provides a more extensive range of colours, greater contrast levels and increased brightness, compared with the colour rendition on standard HD and 4K sets. Some users feel HDR offers more realistic colours. Others disagree, describing them as artificial. Most regard them as an improvement. OLED TVs typically provide better colour rendition than standard LCD sets, but are considerably more expensive. QLED TVs, where Q = Quantum, referring to photo-emissive particles, are a more affordable middle ground. Many reviews state that it is better to have four or more HDMI ports, with one or more in HDMI 2.1 format.
Currently, at Cliff Cottage there is a Samsung 40″ LED HD screen, made in 2010 but purchased used at half the new price (NOK 2 500 vs NOK 5 000) in 2012. We have never used more than two HDMI inputs. One is attached to the media player, the second has an HDMI cable permanently attached, that can be plugged into a laptop. When this screen ceases to function, it is uncertain if it will be replaced with another screen/ monitor. A 4K 55″ television now costs about NOK 5 000. A 4K 65″ is about NOK 7 000.
Projectors vs Screens
One main question is if the quality difference between a screen and a projector outweighs their respective ecological impacts. A large television/ screen/ monitor consumes many kilos of electronic components, that have to be recycled when the novelty/ economic/ physical lifetime of the product is over. My estimate is that a projector weighs < 10% of a television, although I have not undertaken any research to substantiate this claim.
Thus, we will be examining 4K projectors carefully, over the next few years. When our family was living in Molde in 2002-3, we regularly used a projector, borrowed with permission on weekends from the school where we worked. At that time, bulbs were expensive, used a lot of power and had to be replaced regularly. Today, most projectors are either LCD-based, or Digital Light Projection (DLP) based with a laser, LED, or LCOS (liquid crystal on silicon) light source.
If the projector route is taken, a Philips PicoPix Max provides a minimalist solution. It is a wireless native HD projector, running under the Android OS, with a control touchpad on top. Its built-in battery lasts for three hours of projection. It has Wi-Fi, Bluetooth and USB-C connectivity. Its LED projection source should last for 30 000 hours, and project up to a 120″ (3 meter) image. A more expensive alternative is the Aaxatech 4K1 mini-projector, that costs US$ 1 000. It offers 3840 x 2160 (4K) resolution, 1 500 lumens and 30 000 hours of illumination. Another choice is an Xgimi H2 that uses DLP with four channels of LEDs to beam content. Providing 1350 ANSI Lumens of brightness, requires an effective cooling system. This increased light reduces the wash-out of colours and allows daylight viewing. With its own camera, it is able to adjust focus automatically. It also provides auto keystoning. In terms of sound it provides 16 W through two speakers for treble and mid-range, and a diaphragm for the bass. One major problem with many manufacturers is their repeated attempts at vendor lock-in.
Personal comments: 1) For many years, I had hoped that the Gigabyte Brix Projector would evolve into something useful. Currently, it offers a machine with 75 ANSI lumens, which is inadequate for all but the darkest of localities. 2) The use of a projector like the Xgimi H2 will probably mean that the Asus PN 40 can be repurposed, as the projector is its own media player.
Sound
The human audible frequency range stretches from about 20 Hz to 20 000 Hz (20 kHz). The (Harry) Nyquist (1889 – 1976) – (Claude Elwood) Shannon (1916 – 2001) sampling theorem states that sampling must exceed twice the maximum frequency. This means that the rate has to be 40 kHz or more.
In practice, two sampling rates are used. The first, 44.1 kHz used on compact disks (CD) was inherited from pulse code modulation (PCM) adaptors used to transfer data from recording studio tape to CDs, with a sampling depth of 16 bits/ sample. This capability was developed by Philips and Sony, starting in the 1970s. The second, the digital audio tape (DAT) format of 1987, uses a sampling rate of 48 kHz, which is the standard for professional audio.
The HDMI TV standard (2003) allows both 44.1 kHz and 48 kHz standards, although DVD-Video and Blu-ray Discs use only 48 kHz. Most PC sound cards contain a digital-to-analog converter capable of operating native at either 44.1 kHz or 48 kHz. The average human has no need to exceed these capabilities.
Sound reproduction
There are two major ways of getting sound into the ears of listeners: loudspeakers and headsets. The main advantage of loudspeakers is that they distributes sound to multiple people throughout a venue/ house/ room. This is precisely its main disadvantage. There are numerous types and quantities of loudspeaker systems available. Flat-screen displays often come with built-in speakers that are too thin to give a dynamic range people want. Thus, it is common to augment/ replace these speakers with soundbars, mounted either above or, more typically, below the display, to improve acoustics. They are easy to set up, and are usually less expensive than other stereo sound systems. Some soundbars have left, center, and right speakers plus detachable rear-left and rear-right speakers, and a sub-woofer, to provide surround sound. Premium soundbars come equipped with equalizers, which allow the sound to be tuned to compensate for the shortcomings of room dynamics. Despite these augmentations, some people are critical of their small size and/ or position, and opt to use speakers placed throughout the space.
The main advantage of headsets (earphones/ earbuds) is that sound can be individually adapted for each listener. At the same time, people who are not interested in listening to something can avoid it. Perhaps the greatest disadvantage is that every person must have their own headset. Headsets can be wired or wireless. The main advantage of wireless systems is that they allow a person greater mobility. The main disadvantage is their cost.
Appendix: HD vs 4K Displays
Guidelines from the Society of Motion Picture & Television Engineers recommend viewing at a distance where the screen fills up about 30° of the field of vision. Unfortunately, this recommendation does not take screen resolution into account. If one sits too close to a screen, the individual pixels become visible, detracting from the viewing experience. This is also dependent on the size of the pixels. With HD (1920 x 1080), a given size screen requires a person to sit further back, because it is the pixel size that has to be optimized. With UHD/ 4K (3840 x 2160), it is the field of vision that has to be optimized. .
| Type/ limiting factor | 40″ | 45″ | 55″ | 65″ |
| HD/ pixel size | 1.56 | 1.74 | 2.14 | 2.50 |
| 4K/ field of vision | 0.71 | 0.80 | 0.98 | 1.25 |
People are creatures of habit. If they are used to one particular viewing position, they will try to keep that constant, preferring to change the size of the screen, rather than moving closer. This means that consumers are often willing to spend more money to buy a larger screen that optimizes their field of vision, when pixel size issues are resolved.
Other considerations include refresh rates which should be 60 Hz for most activities, although gamers prefer 144 Hz. There is no need for anything beyond this. Note: HDMI 2.0 is needed for 4K video at 60 Hz with 24 bit/px colour depth.