The band was recorded often, but unfortunately not always with the best gear. There were very high quality tape recorders out there like the Sony WM-D6. Some recorders could set manual record levels, use different types of tape, including metal and even utilize Dolby NR on recordings. There were also complete pieces of crap meant for simple voice recordings. Again, this means that metadata is necessary to understand how the master recording was made in order to b able to transfer it properly.
I'm personally guilty of recording them twice with a handheld General Electric 3-5363A Cassette Recorder used for voice memos or dictation. It had a built-in microphone, no ability to set a level and probably was aligned for Type I Normal bias cassettes although I used Maxell Type II High Bias tape instead thinking it was better.
These days high quality cassette decks are getting harder to find. Those that are available may not be the best for archival or may need some work. The speed of the tape is determined by a rubber belt on a pulley that degrades and stretches over time (decades now) and can adversely affect the playback speed and hence the pitch or the music. The belts need to be replaced. The heads and tape path will certainly need to be cleaned as well as many of the knobs and switches.
I use a Pioneer CT-W603RS deck for playback. It has Dolby B/C/S NR and will playback any type of tape formulation. I typically archive my tapes going out of the tape deck analog to a MOTU Traveler line input set to -10dbv and capture at 192Khz/24Bit Stereo. Its overkill, but when there is no other source available you should always use the best quality you have available, in my opinion. After archival I can convert it to any format I desire for convenience.
MD is a bridge between cassette tape and digital PCM recording. Like tape it is re-recordable, compact and durable for everyday use in a walkman type portable device. Unlike tape it has random access, no tape hiss, and can connect to digital devices for playback and recording. Similar to PCM recording it uses a sample rate (44.1KHz) and bit depth (20-24 bit depending on the unit). Unlike uncompressed PCM recording found in DAT recorders, however, it uses a 5:1 lossy data compression scheme (the stereo bit rate=292kbps) similar to MP3. It reduces the required storage capacity by eliminating psycho-acoustically in-audible frequencies from the recording. This is fine for an original recording like when someone records a live concert, FM broadcast, CD source, etc. The fidelity is quite good but never as good as a true uncompressed PCM recording could be.
Where it falls apart is in copying from MD to MD. The 5:1 lossy compression is always in effect when making a recording. Thus MD to MD copies, even over a digital connection have inherit loss from an already data reduced source. This can lead to things like aliasing and artifacts that are clearly audible. This can also happen when recording from lossy sources like MP3 or even digital TV or Radio broadcasts. So it is important to keep track of the generation of MD to MD copies just like with analog cassettes and VHS. There are only so many generations that are audibly acceptable. The proper way to archive or distribute MD source audio is to transfer it to a PCM format that preserves all of the information contained in the recording and allows copies to be made in a non-destructive manner.
All of my MD masters are from a Sharp MD-MS702 recorder in the original/standard SP mode. This unit specifies a 24 bit word length on recording. I transfer all of my MD master recordings at 44.1KHz/24Bit Stereo PCM via SPDIF from a Sharp MD-R2 to a MOTU Traveler using the SPDIF as the clock source. Later MD devices can connect to a computer and transfer the audio as data which is also acceptable.
Digital Audio Tape (DAT) uses standard uncompressed 16 Bit Pulse Code Modulated (PCM) signals recorded onto a 4mm wide magnetic tape. The performance is CD quality or better. Multiple sample rates can be used; 32, 44.1 and 48KHz. Many small portable models became available in the early 1990s and many concerts were recorded with them both from the audience and from the soundboard. Those were often then made into commercial CD bootlegs. It was also possible to make a 1:1 digital clone copy with no loss if you had 2 recorders. Prior to CD-R burners that was common practice and slightly more accurate to the original recording if done at 48KHz since CD requires a sample rate conversion to 44.1KHz. DAT offered the highest possible recording quality of its day. It has only recently been surpassed by flash based recorders due to their size, convenience and their ability to record at higher sample rates and bit depths.
All of my DAT masters are from a Sony TCD-D7 at 48KHz. I transfer DAT using a Panasonic SV-3800 over AES/EBU to a MOTU Traveler using the DAT as the clock source.
From the time period between 1994~2007 in US, at least, the NTSC system was used for all Television broadcasts and home video releases using the 525/60i protocol. Europe and Australia, during the same time, used the PAL 625/50i protocol for all TV broadcasts and home video releases. In some parts of the world at this time the SECAM system was used but very few. While it is true there were HD broadcasts prior to 2009 there were very few households with HDTVs or much less anyway to record an HD signal (like a DVR or capture card). At that point in time there was no HD, no widescreen, no iPhone and YouTube had not quite evolved into what it is today. Although, as mentioned, HDTV had started to roll out it had not become the required standard until 2009 in the USA and 2013 in Australia. Therefore, most of the band's output is in Standard Definition, either PAL or NTSC and is also in the 4:3 aspect ratio. The band was also very rarely shot on actual film (perhaps only their music videos) so again almost all of the band's output, visually, is locked into the Standard Definition system of the country at that time. Only for the last few years was the band shot in HD. Live performances from the Young Modern Era may be in HD but might not....
One of the biggest issues I see with Silverchair's (unofficial) video content available on YouTube is that has been stretched to a 16x9 (1.78:1) Aspect Ratio making the band look shorter and chubbier than in real life. Another is that it is "up-converted" to 50 or 60 frames per second (FPS). All official video from the band is 25 fps with a few exceptions. There is no reason to change the original frame rate. It provides no advantage. Consumer video is either 29.97 in the US/Japan or 25 in Europe and Australia. Keeping the native frame rate intact is important. Exceptions would be videos shot on film (24 fps) and then transferred to video (telecine).
Moving forward in 2020 and beyond those standard definition videos need to be handled with care and attention to the source. VHS was capable of very high quality stereo audio comparable to CD on the HiFi tracks. Unfortunately, even if the master has HiFi stereo, by the time all the copies were made many of my tapes only have mono audio. Additionally several of my VHS copies are from Australia but I'm in the USA. That means many of my VHS tapes had to be converted to NTSC from PAL. This obviously decreases fidelity and adds an analog generation worth of noise. These tapes were not converted professionally either. Likely consumer grade multi-format devices.
These days all HDTVs will display both NTSC & PAL without issue. So at this point it is necessary to find the best proper sources for specific videos and get them transferred to a digital format that can easily be distributed and displayed. Many of these videos that have surfaced on YouTube are of questionable sources and quality. While we are lucky to have them, most of the people uploading them do not have the knowledge or equipment to do it correctly. Dazzle capture cards, stretched out widescreen 4:3 sources, enhancements like de-interlace, de-noise, etc just make me want to vomit. Some look ok, but even then the audio is MP3 128kbps! There is also the catch that you can't really download an entire show. Sometimes the link gets taken down. You don't own anything that's on YouTube in the same way you do when you trade VHS/DVD/Digital files.
I've only videotaped the band 2 times. Actually, it wasn't me but I did pay for the video taper's ticket and he was there on my behalf. The equipment used was a Sony TRV-340 Digital8 camcorder. Digital8 has all of the same technical specifications as MiniDV, only it uses wider tape and thus wider tracks to record the data so it is somewhat more robust. It also records a digital uncompressed PCM audio signal at 48KHz/16 bit stereo. Being a digital format it was easy to capture via Firewire (IEEE 1394) at full resolution. I have digital 1:1 clones of the master tapes.
For VHS sources I'm using a Philips 4 head VR960 NTSC SVHS deck. Composite output goes to a Crystalio II VPS3800 for comb filtering, Faroudja DCDi processing and upscaling to 1080p/59.94Hz HDMI output to a Black Magic Intensity Shuttle USB for capture to Apple ProRes 422 LT. For Hi8/Digital8 sources I have a Sony TRV-230 and for MiniDV sources I use a Panasonic DV950 both use Firewire (IEEE 1394).