here's a little glossary about the words and acronyms we mostly use when we're talking about
the wonderful world of RoIOs and VoIOs...
...first of all, the meaning of the acronym "RoIO" is "Recording of Indefinite/Illegitimate Origin" , so
the recordings we used to call "bootlegs" nowadays are called simply "RoIOs"...
...and the same way, we call "VoIO" a "Video of Indefinite/Illegitimate Origin".
Before starting to list the various acronyms, i'll do a little example just to have a little more practical viewpoint...
If you go to http://www.pf-db.com/index.php?list=years&choice=1972 and point your attention to the November 15th 1972 gig, you can find many roios that belong to that particular gig…
While reading the various columns on that page, you can clearly notice the dates, the titles, the venues, etc… BUT the penultimate column say things such as: “audience/Recorder 2” , “audience rec1” , “audience/Source2/Recorder1”… and what means all that stuff?
Imagine that particular gig in that particular night at Boblingen, where one or more persons, having some recording equipment each one, were recording the gig and each one from own point of view…
Each person of those, that we’ll call simply “recorder” , produced a “Master” recording of that concert… and, through the years, those recordings began circulating dubbed into the various analog and/or digital media such as Reel tapes, cassette tapes, vinyl records (bootlegs) and more recently onto DAT tapes, CD-R discs and lastly through the internet…
You can easily imagine that since that night in 1972 till today a great number of Tapes, Vinyl Records, DATs and CDs were circulated among the collectors with different sound qualities, strictly depending on the quality of the equipment and media that were used by the single persons to create the various circulating copies, all of them starting from the original recording…
Logically, on the internet we can find some of those “copies” that were digitally transferred and uploaded but I guess that a great amount of those old analog copies is still into the closets, uncirculated of simply lost or trashed… and these few copies that are circulating on the internet are more than sufficient to create a great amount of confusion into the average fan/collector’s brain… (myself included!)
As you can see, for that Nov 15th 1972 gig there are in circulation mainly 2 different “Recorders” (really they are 3!) that were simply named “recorder 1” and “recorder 2” where the number follows the chronological order in which the respective copies began to circulate among collectors, so the “recorder 1” copies went into circulation before the “recorder 2” copies…
So the first thing we must do, when identifying a recording of a particular gig, is to find out which “recorder” we are listening to… and the main things we have to check are all those “local” details such as noises and chats we can hear near the taper, because normally those details are clearly different when listening to the different recorders… other things that may help to identify a particular source are the sound quality and/or the completeness of the recording itself, due to the different equipment and media used by the single “recorders”… (but these things can be much variable between the various following copies, so the analysis of the local details is the only method that gives 100% accurate results)… logically to do the right comparisons between the recordings we must have some of them to put side by side and listen very carefully…
At this point it’s clear that we all would like to have the best sounding copies of a particular recording/gig in order to have a clearer and more detailed sound and with less tape hiss but how we can identify the copy that is supposedly “best sounding” and/or nearer to the “Master” of a particular recording?
No problem… the “lineage” can really help us… and what is the “lineage”?
Well, it’s simply the list of the single passages (where known) of the copies that our particular recording consists of…
But let’s do some example, just to clarify the matter…
The roio named “(untitled) 1st gen (recorder 1 –source 1)” , the roio named “m[reel]>dat>cass>cdr(?)>shn (recorder1-source2) and the other one named “The Great Gig in Boblingen (recorder 2)” are clearly different recordings of the same gig and have different lineage also…
…let’s analyze their “lineages”…
M[Reel] > cass > cdr[?] > shn --> (aud-rec1-src1)
m[reel] > dat > cass > cdr(?) > shn --> (aud-rec1-src2)
cass[very low]>cdr[?] --> (aud-rec2)
The first two roios both come originally from the “Master Reel” produced by the “Recorder 1” person but the first was copied to a cassette tape and then to a cd-r disc, while the second was copied to a dat tape and then to a cassette tape and last to a cd-r disc…. So they are completely different branches of the same original master recording and we call them “source 1” and “source 2” because the first one went into circulation before the second one…
Logically the third listed roio comes from another completely different “Master” recording, made by another person (the so-called “Recorder 2”)… and was a copy made into a cassette tape and re-copied into some other cassette tapes (supposedly for few times) and then to a cd-r…
…as you can see it’s not much simple to orientate into these many recordings but without a strict “code” system it may be much harder… and so I finish my introduction and go directly to the glossary…
Audience recording (acronyms: aud, au, a) : this is the classic recording made by using one microphone (or more) by a person that is in the audience (the so-called “recorders”) and we will identify and distinguish them by using a number each one. (i.e.: rec1, rec2, etc…);
Soundboard recording (acronyms: sbd, sb) : this is a recording taken directly from the soundboard/mixer;
Radio broadcast (acronyms: ra, FM, AM, b/c) : this is a recording taken from a program broadcasted by a radio station. Generally radio broadcasts are originally sourced from the soundboard, eventually with some editing, cuts and processing made by the sound engineers of the radio station to optimize the sound for the broadcast;
Television broadcast (acronyms: TV) : completely similar to the radio broadcast but going through a television broadcast/device;
Studio recording (acronyms: stu, std, st) : recording originally produced in a recording studio, generally sourced from a soundboard. Logically the “demos” and the “out-takes” belong to this kind of recordings, apart from those “home-demos” that could be originally produced in different ways;
Video recording (acronyms: vid, vi, v) : audio recording sourced from a videotape and/or an archival videotape from a television studio;
Film soundtrack (acronyms: MV) : audio recording taken from a film soundtrack;
Master (acronyms: mst, m) : we call “master” THE original recording of a sound, so the tape (or another medium) that was recorded directly during a gig (or during a broadcast) is the master of that particular recording. Logically each “audience recorder” has its master and if a gig is recorded also from the soundboard then we would have the soundboard master too.
Pre-fm master : generally it’s a soundboard recording that a radio station edits as the source material to be broadcasted. In most cases, the radio station is allowed to record from the soundboard into multi-track and then they perform a mix of that multi-track material into a mono or stereo recording for broadcasting and/or for archival purposes. Logically a pre-fm roio is intended to be sourced directly from the archives of a radio station and NOT from its broadcast.
First generation (acronyms: 1st gen, 1st, 1) : the first generation is a direct copy from a master recording.
Second generation (acronyms: 2nd gen, 2nd, 2) : the second generation is a direct copy from a first generation copy of the master recording. (and so on with the following ones…)
Low generation (acronyms: low gen, low, l) : if we don’t know for sure which generation our recording is, but we imagine there were very few generations between the master and our recording… so we call it simply “low generation”.
n-th generation : sometimes I saw this n-th acronym when we have a copy of unknown generation but with many generations between our recording and the master. A similar way is to label a recording as “high generation”.
Unknown generation (acronyms: ?) : if we don’t know the generation at all and we neither cannot guess anything about that… so we can simply call it as “unknown generation”.
Clone (acronyms: cl, c) : when we have a direct digital copy of a digital recording, made without re-converting the sound (for example 2 DAT recorders digitally connected or similar situations) in order to have a “bit by bit” identical copy, so we call it simply a “clone”.
And sometimes I saw people calling as “clones” the digital copies of unknown generation.
Generation “0” : sometimes I saw people calling generation 0 (zero) the master recording and/or a copy that was the first into its particular medium.
*MOST USED PHISICAL RECORDING MEDIA*
Reel to Reel (acronyms: Reel, RTR) : it’s the good old open reel tape, used for years and years by professionals and audiophiles. If the tape and the recording machine are of high quality, so we can achieve the best sonic results in terms of wide frequency response, warmth of sound and low noise level, remaining into the analog domain. We can find reel tapes of different width (from 1/4 inch to 2 inches) and we can use different recording speeds (usually from 1 7/8 inches per second to 30 inches per second, or ips). An increased recording speed will reach higher sound quality, in terms of wider frequency response, lower noise, less noticeable drop-outs and less “grainy” sound and higher dynamic range… but an higher cost because we need more tape length to record for the same time.
Cassette (acronyms: cass, c) : the mythical compact cassettes, easy to use, easy to store and easy to transport… they were the most used medium during the 70’s , the 80’s and the 90’s…
Its tape has a width of 0.15 inch and a speed of 1 7/8 inches per second and achieves a really good sound quality, especially when using good cassette tapes and decks.
There are different types of tapes, based on different types of oxides used… principally the Ferric ones (called also “normal” , “Fe” or “Type I”) , the Chrome ones (called also “high” , “Cr” or “Type II”) and the special ones (called also “Metal” or “Type IV”) and there were also different lengths from 30minutes (15min. per side) to 120minutes (60min. per side).
Generally the “Chrome” tapes were better than the “Ferric” ones, as they achieved a wider frequency range and a brighter sound… while the “Metal” tapes have a wider frequency range and also an higher dynamic range, so they generally sound louder, brighter and with less “hiss” than the others.
LP (vinyl) : this is the “classic” pressed vinyl record. When a vinyl record is handled, used and stored with sufficient accuracy in order to reduce its wear and the dust into their grooves then it can be really one of the best recording media in terms of sound quality and stability over the years.
If we play a vinyl record using a good and “well tuned” turntable and a good cartridge/stylus (for example a good “elliptical” one) we can achieve a wonderful “natural” sound (similar to open reel’s one) and long lasting use. You can notice that the good old vinyl bootlegs are recordings of very low generation and they sound as the day they were produced without the typical “loss” that gradually occurs into a tape, passing the years… Naturally the vinyl records MUST be stored and used the proper way, otherwise we can wear or damage them in very little time and with very little plays.
Acetate : it works just like a normal vinyl record but normally it’s not pressed (as vinyl LP does) but an “acetate” is cut with a special “cutting stylus” starting from a blank disk.
Generally the acetates are part of the vinyl producing process, as we record (cut) the groove on it starting from a master reel tape… and then, by a galvanic process, we create the metallic matrix disc that will be used to press the usual vinyl records. Sometimes, in the old days, acetate discs were also cut at home (with very expensive equipment) and used as a very high quality recording medium and/or in a recording studio to produce a demonstration disc to valuate an eventual mass production vinyl record. The negative aspects for the acetates are that the material in which the groove is cut is softer than a traditional vinyl record so it wears rapidly after very few plays.
8-Track : this is the old 8-Track cartridge and is somewhat similar to the cassette tape. Into a cartridge there is a continuous loop of tape mounted in a particular “endless” reel. The tape width is ¼ inch and runs at 3 ¾ inches per second. The name “8 track” is because on its tape are stored 8 different tracks (normally joined into 4 stereo tracks) and theoretically the sound should be superior than a cassette tape (because of its double speed). But the cartridges were also famous for their great facility to lose the correct azimuth alignment with the tape head when switching from a couple of tracks to the others (in stereo mode use).
Best results can be achieved using these cartridges as multi-track (up to eight) storage media, but the multi-track decks that can do that are actually unavailable. Another negative thing about these cartridges is that the tape can run in only one direction, so a “rewind” is not really possible at all.
VHS : this is one of the most used standards for the cassettes for video recordings (another one was the old Betamax) that was often used in the past as a replacement for the standard cassette tapes.
The tape contained into a VHS was often of an higher quality and durability than a standard cassette tape so such VHS were often used as an audio only storage medium. The most used acronym to indicate an “audio only” VHS is simply “Hi-Fi” , rather rhan “Hi-Fi VHS”.
DAT : this is the first (and the most used) digital storage medium, appeared during the eighties. Into a DAT tape we can record digital audio up to a resolution of 16bit and a sample rate of 48Khz, a little better than a standard CD. A good thing was that when using two DAT decks connected in a digital way we could “clone” a DAT tape without adding any generation loss, as the digitally copied tape was the exact same as its source. Logically this fact works when, using direct digital connections, we do NOT pass through the converters involved at the analog connections of a DAT deck.
Moreover, DAT tapes were also used in the recording studios to store the master of a mixed multi-track recording, as a replacement for the 1/4 inch reel tape, when producing a CD album.
CD (silver pressed) : the classical silver discs, factory produced by pressing them using a matrix with an industrial process somewhat similar to the vinyl records’ production one.
They are extremely durable and can store the digital sound with a resolution of 16bit and a sample rate of 44.1Khz.
CD-R (or CD-A) : they are the compact discs that can be recorded using either a stand-alone CD recorder or a CD burner mounted into a PC system. As audio quality they are identical to the silver pressed CDs and nowadays we use them for many things. (i.e. for data storage).
The “generation loss” matter is similar to the DAT tapes, so if two CD recorders are digitally connected we are simply cloning a recording. The same thing occurs when we use to copy a CD using a Personal Computer with a CD burner. The negative thing about these CD-R are that they are not “eternal” at all, and the humidity, the continuous temperature changes, the exposure to the light (especially direct sunlight) , the chemical agents and the abuse can deteriorate the disc also very rapidly, so take care of them and possibly make some backup copies to prevent the “disasters”.
Mini Disc (or MD) : a sort of floppy in which we can store the digital audio with the CD quality (44.1Khz / 16bit). But minidisk can also save the sound into a proprietary compressed format (named ATRAC) that has really bad artefacts and so this kind of compression is NOT adequate if we want to record with a good quality. Very simple to use and really portable it hadn’t a good success (at least here in Europe) so the price of the MD recorders and the blank diskettes remained pretty high, and nowadays it’s a really obsolete system.
DVD-R : principally used for data storage and for video use, the DVD-R disc can be also used as an “exaggerated” digital audio storage medium, but only if we use a Computer to sample and edit the audio material the proper way. A DVD-R disc follows the DVD-Video standards, so we can author a sort of DVD-Video (playable on the standard DVD players) but without the Video track (i.e. we’ll have a black screen) and with the audio track at the sample rate of 48Khz or 96Khz and with a resolution of 16bit or 24bit!!! For example, with 24bit/96Khz stereo tracks we can store up to 2 hours of impressive high quality audio onto a single DVD-R disc. We can also use it to play multi-channel audio (such as Dolby Digital AC3 or DTS) but in this way the sound is somewhat compressed with some quality loss.
While using it in Stereo-mode we can record really lossless digital linear PCM samplings to achieve a superb quality. For your information, if I use a 16bit 48Khz audio (the maximum “DAT” quality) I can store up to 6 hours of music into a single DVD-R disc! (up to 4 hours at 24bit 48Khz, up to 3 hours at 16bit 96Khz and up to 2 hours at 24bit 96Khz). I want to put in evidence that with a 24bit 96Khz audio transfer I can really put into a digital medium every little detail that we can hear into the highest quality analog media (such as Reel tapes and vinyl records) , but another important thing to be noticed is that on our stand-alone DVD player we MUST disable every feature such as “auto convert to 48Khz” and/or “dynamic compression” that are often enabled by default, in order to really hear the untouched 24bit 96Khz audio signal straight into our audio system. In my opinion, with the standard DVD-R disc used this way, the new (and expensive) digital standards such as “DVD Audio” and “Super Audio CD” can wait for a while…
When we read the lineage of a roio we can notice that , if they’re known, we find information about the devices used to record the master (i.e. microphones and recorder device) and also the ones used during the copying passages (i.e. tape decks, dat decks, cd burners, pc soundcards, etc…) but generally the thing that influences more the quality of a recording, in my opinion, is the quality of the microphones used when taping the master and most of all the right position and distance of the recorder (and the mics) from the P.A. system, in order to avoid the unwanted saturation and clipping and trying to enhance the clearness and that little stereophony that we can obtain into the ambience (but unfortunately this is not possible all the times…).
*MOST USED AUDIO TREATMENTS*
In the old days, when we used to exchange our recordings on vinyl and tapes, generally we did NOT make any audio treatment to the recordings, but we simply listened to them…
But nowadays, where modern Computers can do virtually anything, things are really changed!
With a standard PC and an audio editor, anyone can do also at home any treatment to the sound.
So, today, many people tweak the sound in order to try to eliminate some of the defects they find into the recordings… in my opinion the most important thing is to try to fix a defect but WITHOUT adding unwanted digital “noises” that very often are worse than the “defects” we had before the tweaking.
Naturally, before tweaking a recording, it’s very important to listen to it very carefully BEFORE doing any sonic treatment and most of all it’s a good thing to know really what we are doing… Today, too often, a person with a PC and an audio editor automatically thinks he is a sound engineer, but the complete lack of knowledge and experience on that matter is almost the rule, unfortunately… so we have a great quantity of recordings floating around that were irrevocably ruined by such “expert” persons…
My honest advice is that if you’re not 100% sure about what you’re doing then do NOTHING to the sound, or at least do that for yourself and don’t put into circulation such “re-mastering” projects…
…the “do it yourself” is NOT the best thing, when talking about audio tweaks and enhancements…
…but now let’s talk about the principal “defects” that affect the recordings (and some possible remedies)…
Speed problems: we know that two different tape decks may have some little differences in terms of tape speed, so a tape that was recorded on a deck could play on another deck with a wrong speed.
Sometimes those “little” differences are not so little… especially when a recording is an high generation tape copy because we could add a “little” difference each new generation…
The wrong speed sometimes could be caused also by the portable recorder used during the concert, especially if it’s a cheap one or if the batteries are getting low power… and when at home we play that tape on a good tape deck (that should run at the correct “standard” speed) we are listening with a speed that is different to that in which the tape was originally recorded… If we have a tape deck with a speed control (often called “pitch control”) we can simply correct the speed while listening to the tape, otherwise we’ll play it how it is…
Speed correction: digital sound systems completely eliminate the “speed” problems, because digital audio is based on the “sample rate” principle and so the speed remains virtually constant between the different digital devices… so, if I record a gig using digital equipment (i.e. a DAT deck) I will play it at the same right speed also on other digital devices (and its digital copies will do the same).
But if I capture a recording from an analog medium (i.e a cassette tape) that runs at a wrong speed to a digital medium, so I will create a digital recording that will always run at the same wrong speed.
So it could be useful to correct the speed of a digital recording that runs at a wrong one, and this is one of the most common audio treatment we find around. Logically, to really “correct” the speed we must have the right reference tuning that was supposedly used by the band during the concert.
But it’s also important to tell you that the digital speed correction process is NOT a process without bad side effects on sound quality, and very often these “side effects” are understated by most people.
So, the best way to correct the speed of a recording would be to play the original tape at the correct speed while capturing to the digital domain, in order to avoid such digital post “re-sampling” treatment… but it’s not always possible to do that… so the digital speed correction is one of the most used processes…
Hiss and Noise Reduction (NR): another typical problem on the analog recordings is the “tape hiss”…
…and when we copy a tape to another blank one some amount of hiss is simply added to the original sound… so an high generation tape has a great amount of hiss! There are many kinds of noise and hiss reduction processes, such as the old analog “dolby system” on the tape decks and the many digital noise filters… Unfortunately it’s much common to find a digital roio where there is an abuse of digital hiss-reduction, and the abuse of this “NR” (but also the simple “use” of it) ruins the sound in a really bad way… while we are reducing the tape hiss we are also reducing the sound itself (especially the high frequencies) and so we’ll lose forever the clarity of a recording and in the worst cases we’ll obtain a “water-bubbling” effect, that is really annoying (I prefer by far the hiss than these bad NR side effects). On the other hand, the analog NR systems (such as dolby system) use a totally different approach, and they work as a dynamic expansion/compression on some frequencies, reducing the clarity of the recording but without the bad water-bubbling side effect… Resuming, I say that if we can’t stand the hiss so we could appreciate the use of these NR processes but if we like to hear the brightness of a recording then we should avoid the NR at all! (the tape hiss is one of those things that our brain automatically “excludes” after only some minutes we are listening to a recording… while the bad “metallic-sound” and/or water-bubbling side effects, due to the use of the NR, are really hard to neglect during the listening). In very few cases, some really expert technicians can do something good to reduce “a little bit” the tape hiss but most times it’s BEST not to try to reduce the hiss at all! (and this is why most people are searching roio recordings that are possibly “unprocessed” or “raw”).
Clicks, Pops, Crackles: they’re all those defects we can hear, for example, on a dusty (or worn) vinyl record. Sometimes also tapes have some clicks (but they sound different from the ones from vinyl LPs).
Generally we call “click” or “pop” an instantaneous noise that has a level above the sound itself, while the “crackles” are all those little clicks that have a level below the music, as a background.
We have principally two methods to eliminate these defects: automatic and/or manual “declick”.
The automatic de-click is very fast and simple to perform, but it has the side effect that, while filtering the clicks and pops, we also filter something into sound as dynamic transients and some high frequencies, so it’s NOT the preferred way to edit a “dirty” track.
The manual de-click, on the contrary, is performed by selecting only the audio portion that contains the click and redrawing the waveform only for those few milliseconds… so the side effects on the sound are really inconsiderable! But to do a good manual de-clicking we have to pinpoint and select the clicks one by one, so this is a difficult work and it takes many hours (depending on how much clicks we have to remove)… so, if we want the best results we have to take in count that we must work very hardly while restoring a recording.
If we are starting from a vinyl record it could be a good choice to clean the record as best as possible, so many clicks go away with the dust we remove from the vinyl grooves and, of course, the following digital editing will be far less hard to do properly.
I have to mention also the digital clicks, that we can remove the same way, and with near-perfect results.
Clip, saturation, distortion: each time the sound level exceeds the maximum level that a medium can correctly handle then it does occur some distortion into the sound.
For example, when we record a tape over its saturation level or when a microphone is under a sound pressure that its diaphragm can’t handle (when we are too near to a P.A. loudspeaker) or when we put into a mixer or an input stage a too hot signal...
The saturation into the analog realm and medium, initially, comes in a smooth way (as a sort of dynamic compression) and if the signal is too hot then the sound becomes really bad.
And when we are recording using digital equipment we must absolutely avoid to exceed the “0 dB” at the Analog to Digital (AD) converters, otherwise we’ll have some digital “clipping” on the sampled waveform… the digital clipping is a very “hard” distortion and the sound keeps “crackling” immediately when we go over the 0 dB level.
Unfortunately we cannot do almost anything to fix the distortion so we should avoid it by checking the recording levels very accurately before it occurs.
The only little thing we can do is when we have a digital recording that has some slight clipping only at the peaks (that will be a bit flattened) and we will hear some single clicks, but if the distortion is in the “mid” of the sound (like the saturation) we cannot do anything to fix it properly.
Stereophony and Phase correlation: sometimes also audience recordings are Stereo because the recorder used two microphones to capture the sound during the concert. This way we’ll have some stereo separation on the high frequencies but almost nothing on the bass frequencies, because bass frequencies do not propagate in a directional way. So, if we have some stereo separation on the bass frequencies much probably we have a bad phase correlation due to a bad microphone placement and that “separation” is not a real stereophony but a side effect of the bad phase correlation that occurs as an erasing of some frequencies between the two stereo channels, while listening.
In other words, in audience recordings we should look at the bass frequencies as some sort of “carrier” signal that should be “phase-aligned” correctly into the two channels… and the high frequencies will be our “out-of-phase” stereophonic signal.
On the contrary, stereo soundboard recordings have two distinct sources for each channel and so the bass frequencies can be different between the two channels, and if we have a bad phase correlation then it means that the mixing engineer did a bad work on the mixing console (or it could be some wanted “artistic” choice).
Logically the re-alignment of the phase is something we can do very well with modern audio editing software (logically we must know what we’re really doing, eheheh).
*MOST USED DIGITAL AUDIO FORMATS*
First of all we have to distinguish linear uncompressed digital signals from the compressed ones.
And then we have to distinguish the lossless digital streams from the “lossy” ones.
The difference is that if we compress a linear PCM digital sample to a “lossy” format (i.e. mp3 format) then we reduce the quality of the sound and we will never recover the frequencies and dynamics of the original digital recording from that lossy version of it.
Uncompressed formats: digital equipment (like CD and DAT) use a linear PCM digital sampling technique that take a “shot” of the sound many times a second with a certain rate (the sample rate) and with a mathematical precision and accuracy that is the resolution in bits.
An higher sample rate can capture higher sonic frequencies and an higher resolution “draws” the signal with an higher dynamic range and more accurately.
Compact discs have 44.1Khz of sample rate and a resolution of 16bits (so we have 44100 samples a second of 16bits each one) while DAT tapes can reach a sample rate of 48Khz at 16bits.
For example, if we rip a CD into our hard disk to a WAV file (or similar formats like AIFF) we will have an identical sound that will be about 10Megabytes for a minute of stereo recording.
Logically a DAT tape at 48Khz/16bits, if converted to a WAV file, it will produce about 11Megabytes of data each minute of recording.
Now it should be clear that WAV and AIFF are the most used uncompressed audio formats into the computer’s realm.
Lossless compressed formats: these formats permit to reduce the size of an uncompressed file (WAV or AIFF) about at half of its original size without modifying the sound at all! So we can convert, for example, from WAV to a lossless format and back to WAV file without any difference in sound quality with a bit by bit identical transformation. Logically these formats are nowadays preferred to store and/or exchange by the internet any recording maintaining its original sound quality while reducing the amount of data. The most used lossless audio formats are: SHN, FLAC, APE, MKW.
Another useful thing is that we have many software players (and also some hardware ones) that reproduce directly the lossless files without the need to convert them into an uncompressed format or to burn into a conventional audio CD.
Lossy compressed formats: these formats permit to reduce the size of the original uncompressed file (WAV or AIFF) much more than how lossless formats can do (even 1/10 of the original !!!) but to reach such data reduction the sound is filtered and the sound quality suffers.
If we listen to a lossy format through the cheap PC speakers probably the sound will seem good, but if we have a good set of loudspeakers we’ll notice that the high frequencies are cut and the dynamic range is reduced and this loss has also some side-effects such as a “metallic sound” on the high frequencies (most notable on cymbals) that is a sort of weird modulation that grimes the sound and eats the details.
If you analyse the frequency spectrum of a lossy audio file you can notice that the frequencies are simply cut about at 15-16Khz and above that cut there is no more sound (this is the trick we generally use to discover if a CD was burned from lossy files or not).
Most used lossy formats are: MP3, MPC, OGG, WMA
Logically they are completely unacceptable in the trading communities!
Fingerprints: “md5” and/or “ffp” fingerprints are an useful method to verify if the files are good or corrupted or to verify if the files are the right ones or not. Basically a roio circulates in a lossless format along with the fingerprints (that is simply a code) generated when the lossless file was created in the first place. So, we can really identify a file by its fingerprints being 100% sure!
Most used software applications to handle, convert and verify lossless audio files are: Trader’s Little Helper (TLH) , MKW audio compression tool (MKWact), FLAC frontend, Monkey’s Audio…
*SOUND QUALITY GRADING*
We use numbers (from 1 to 6 or from 1 to 10) to grade the sound quality of a roio recording but also some acronyms like the following ones.
(SUP-EX-VG-G-P-B): superb -> excellent -> very good -> good -> poor -> bad . we use also "+" and "-" just like at school...
(A-B-C-D-E-F): "A" is for the best quality and "F" is the worst quality (also with "+" and "-").
I hope this little guide will be intelligible and also a little useful to give you an orientation into the various world of roio recordings.
Thank you for reading, Vinz.
(Guide built by Vince666)
(English revised by Andrew)