Contents

 ** TECHNICAL   NOTES ** 

Credit Card Security
 
Collector  Exchange

Postage & Shipping

CD  Mailers

Quality of Recordings
 
Audio  Clips

Audio  Notes

Recording  levels

Normalising recordings

Disc  copies

Audio DVD

Useful links

Home

CREDIT CARD SECURITY
This is not a secure website so there is a slim chance that your order details might be intercepted by a third party.  Probably about the same odds of your being trod on by an elephant.  In over ten years of trading, there has never been the slightest hint of order details misappropriation.
But one does not want to tempt fate so if you are really nervous about transmitting your card details, you can send the numbers over split emails an hour or so apart.  Simply enter a string of zeroes in the Order Form where the card numbers go.
Once I have your number,  it is not required again until the details change.
Just enter zeroes and the  LAST  four numbers,
and the expiry date on your Order Form.
None of this information is stored on the website.

How secure is your credit card online?
The risk of your credit card details falling into the criminal hands when you make an online purchase is real – but remote.
 In fact, the risk is about the same as giving your details over the phone.
Amazingly, not  using your credit card doesn’t make you any more safe.
Criminals have had credit card number generator programs for years. 
These programs use the same algorithms as banks to generate thousands of potentially real credit card numbers. There’s a small possibility that the software will eventually generate your credit card number, purely by chance.

And don’t let yourself think that small transactions are any less important.  A small debit may be one way for criminals to ‘test’ your card. Or it may be part of a much wider fraud. For example, The US Federal Trade Commission uncovered scams that netted some $50 million through thousands of $20 debits.

The best way to protect yourself and your cards is to always check your statements thoroughly as soon as they arrive (or more frequently online, if your bank offers Internet banking services).  It is also a good idea to establish a card with a modest credit limit  and use that for Internet purchases.

QUALITY OF RECORDINGS:

Celestial Audio 
is not a record company nor a private record label.

It is a service to opera collectors unable or disinclined to make their own recordings and who appreciate quality presentation and well-mastered recordings.
You get what you pay for.  In most cases they are the best-sounding editions available, apart from fully commercial releases off the radio master.

Occasionally I am asked about the sound of certain recordings in the catalogue.
The Audio Clips on site should give a good idea of the general level of audio quality and inspire some sort of confidence in that the recording you receive will be of an acceptable listening standard.  
The vast majority are far more than that, ranging from good to excellent.
I do not bother with poor quality recordings  .... unless it were a complete opera sung by Caruso  .... 
or something that is very rare and there clearly is only the one common source recording.

An exception is recordings in the  LIMITED EDITION  series.
These recordings have considerable importance or rarity value but may not meet
current standards of audio quality for one reason or another.
Often they were made under difficult circumstances and usually no better copy is available.  
They are offered as Historical Documents in that they are worth preserving to be appreciated by those who care about these things.  In essence, they are for those who can cope with a bit of crumbly sound now and again.  
But if you know Celestial Audio standards, you will anticipate that it won't be too crumbly !

AUDIO  CLIPS:
Web space is limited and audio clips take up a lot of space.  Where a recording or artist may be relatively unknown or where the recording is significantly better than other available editions, an audio clip is included on site.   The Catalogue Disk is updated yearly and contains a far greater number of audio clips than is available on the website.
Ask for a disk if your copy is out of date.
There is no charge for it when included with an order.


AUDIO NOTES:
The conventional compact disc may be nearing its use-by date as a fine-music carrier.
Its playing time is not much more than two LP sides and its audio performance can be bettered. 
The CD specifications were set in the dawn of the digital age and there has been a lot of progress made since then.  Current model, quality DVD players now sport 192kHz/24-bit digital to analogue converters and are capable of playing just about every disc format.  

SACD  (Super Audio Compact Disc) shows off the superiority of higher sampling rates.

As many of you know, the choice for the home recordist has not been an easy one. Carefully adjusted cassette recorders gave good results but there was always the awkwardness of judging appropriate spots to switch tapes. VHS HiFi with its long tapes solved the problem of playing time but cost-cutting measures whisked away the recording level meters and if one was unable to replay the tape on the machine on which it was recorded, there was often a nasty VHS bass rumble in the sound. 
Currently, many home DVDs are variously affected by that artefact in their audio output.

Some people took the mini-disc option but to my ears, that format lacks a certain element of harmonic detail and of course, playing time is again limited.
Others went with CD recorders and spend a lot of time hoping that the aria would end before the disc did.
DVD recorders appeared that gave a similar audio performance to CD when used in the High Quality mode and enabled one to record in linear PCM.
Many of the latest models have ditched that option and record their audio in a compressed format  (AC-3).
Keen ears notice the difference.

All of which begs the question of how best to record those opera broadcasts we love to collect.
If your idea of good sound is a webcast at 128kbps then you don't need to worry about this.
High quality analogue and digital broadcasts are best captured by high quality means.
Even if you are only vaguely computer literate, the answer is to use the computer!

Having a quality sound card installed is essential.
It will allow you to make high quality recordings at the higher sampling and bit rate of 48kHz/24-bit rather than the lower resolution sound of 44.1kHz/16-bit which compact disc delivers. 
More "bits" captures the signal in greater detail.
These high quality recordings can then be burnt to an Audio-DVD. 
The software required is cheap and easy to use.
Your recordings will play in your fancy new DVD player and furthermore, take up a lot less shelf space as the complete recording will fit on one disc.
At this high data rate, one has a playing time of about four and a half hours !
Recording at the lower resolution of 48kHz/16-bit gives a disc playing time of over six and a half hours. That's two whole operas on one disc in CD quality sound!  Or, if you've got cash to splash, you can go for something like the Yamaha AW1600 Hard Disk Recorder which has a USB connection that will allow your recordings to be transferred easily to the computer to be burned to disc.


On the matter of 
Collector Exchange  where I occasionally receive enquiries:-
What I am most interested in is good quality  original source recordings  rather than ones that have originated from other dealers, or semi-"commercial" editions that have circled the globe many times and gone through several transformations ..... not always to their benefit.
Definitely no webcasts, and minidisc sources only if they are live inhouse and reasonably immediate in sound.    Avoid using the LP4 mode as this is a severely compressed format that loses much of 
the harmonic detail in the sound and does not give a particularly pleasant result.    Keep to Stereo Mode.
Please remember that what satisfies you as a good aural souvenir of a great night in the theatre, may not satisfy the general listener.

Incidentally, minidisc users may not be aware that a new breed of portable minidisc recorders offer the option of recording in uncompressed, linear PCM sound.  Latest models have no moving parts and store their data in flash memory.  Extra high quality  96kHz/24-bit recording is possible with these newer machines which are now available at a reasonable cost.
Used in conjunction with a good microphone, these recorders promise high quality sound on a par with and beyond  compact disc, rather than the compressed ATRAC format with its digital manipulations.

Good analogue sources like cassette and open reel tapes provide excellent material for quality CD transfers.   If you have these and are unable to process them, I can do it for you. 
Don't hesitate to contact me on the matter.

AUDIO DVD .........
Some people are still uncertain about the nature of the Audio-DVDs in the catalogue, mistaking them for videos.
These are all  AUDIO  recordings and 
NOT videos.  I do not trade in video recordings.
DVD  stands for Digital Versatile Disc and the discs can be used to store any sort of digital information: text files, graphics, audio files or video files.
Regular DVD discs can have audio encoded in various formats.
Generally, the audio is compressed to allow room for better picture quality.

The most common format and the one generally found on most DVD recorders is Dolby Digital (AC-3).
It is a perceptual coding algorithm developed to allow the use of lower data rates with a minimum of perceived degration of sound quality.    Another audio format is DTS which uses less COMPRESSION than Dolby Digital, and has a lower bass extension, so in theory it sounds better.

Bit Rate is the term used when speaking of video or audio quality -- it defines how much physical space one second of audio or video takes in bits.
Linear Pulse Code Modulation (LPCM) is an uncompressed audio format.
On DVD it can use an audio sampling frequency of 48khz or 96khz  (which governs the number of audio samples taken each second)  and 16, 20 or 24 bits per sample (which is the number of bits making up that sample).

Regular Compact Disc uses an audio sampling frequency of 44.1kHz and a bit rate of 16.
Compressed Dolby Digital and MPEG audio can have a bitrate that is as low as 10% of PCM audio.

The highest quality, uncompressed audio on DVD is linear PCM at a slightly higher sampling frequency  than normal compact disc.    Audio-DVDs  achieve even better than this, in that the higher bit rate of 24-bits is used to capture the original source recording.  This results in finer detail in the sound and is considerably superior to conventional compact disc.  It is the most efficient method of archiving source recordings since you get  higher quality sound and a vastly extended playing time over CDs . 

And when created with the appropriate software,  Audio-DVDs  are playable in conventional  DVD players.
But remember to select the PCM audio output stream from your DVD player and not Dolby Digital.
Audio-DVD recordings in the Celestial Audio collection are all mastered from first or second generation source recordings. 
They are not copies of copies.
If you require CD copies of your Audio-DVD (to play in the car !)  .... a most easy-to-use program called 
DVD Audio Extractor  can be downloaded from the Web.  It will rip the audio from any DVDs and convert them into CD compatible audio files.
 
LONGEVITY OF CDR DISCS
CDR discs may not last "forever".
Indeed, one occasionally comes across requests from collectors who have found their discs to have "gone bad".
Large, external Hard Disc Drives are now quite inexpensive and it is a good bit of insurance to back-up your CDR recordings.
Using a burning program on the computer, you can copy the CDR disc as a "disc image"  -  using the program's  "image recorder" and then you will have a vastly less corruptible copy which can be burnt to a regular CDR at any time if required.

NORMALISING .......  and  RECORDING  LEVELS  ...

Many computer audio management programs include a feature called  "Normalisation".  
It sounds like a sensible thing to do.
When a group of different items are compiled into a collection, normalisation will bring each item up to a similar audio level so that on playback, there is not a wild disparity between the volume levels of the separate tracks.   However, in continuous concert music that has been split into tracks, normalisation can have a quite adverse effect on the dynamics of the complete performance.  
It is best avoided.    Especially within a CD burning program.
When making recordings, a degree of  'headroom'  is a very wise precaution. 
Unlike mild analogue overload, digital overload (clipping) is not in the least bit forgiving and is a distinctly unpleasant listening experience.   Avoid recording out to zero decibels as most metering is not sufficiently accurate to do this with complete safety.   Especially on CD Recorders.   

Unlike recording to tape, you
can't afford to record any distorted input at all.  
Tape can handle a little overload but digital recording can not.  You can tell a file that has been recorded at too high a volume when the waveform is all squared off;  the "crew-cut" effect.
Use your level meters to make sure that you do not let the input level go past the ' 0db ' mark.  
In fact, try to keep it a decibel or two below this to be safe.


DISC COPYING  (
On the fly)
Yes, I know it says 52X burn speed on the disc label !  But there are other issues that need to be taken into account.   It's asking a lot of a CD burner to produce its best results working at the outer limits of all its tolerances.  If you are burning direct from the Hard Disk, high burn speeds can be set.  However, if you are copying from a CD/DVD Rom drive to a burner, then all sorts of other issues come into play.

It is not easy to guarantee an accurate burn because some CD-ROM audio data reads considerably more slowly than "normal" data (Mode 1 or Mode 2). For example there are modern 48x CD ROM drives which read audio data slower than 10x! 
If errors occur when reading the CD - because there is a scratch on the CD for example - the error cannot possibly be eliminated by reading the appropriate point of the CD several times because, unlike the image file approach, there is no time (threat of buffer underrun). In such a situation there is nothing else the burning program can do but write the questionable data received or just null data. In other words direct copies are very susceptible to read errors! 
Many CD/DVD-ROM drives are unable to provide information about the number and type of sessions. They can only give information on the number and type of tracks. This means that an exact copy of the CD may not be made.  Audio tracks may contain index positions.  However these can only be identified if the appropriate point on the CD is being read. When producing a "disc-at-once" copy, this information does have to be available before the burn process is begun. This means that with fast copies the burning program may not copy audio index positions at the same time. These will therefore inevitably be lost!   The quality of audio data read in, may suffer here. 
The CD/DVD-ROM drive often reads at a higher speed than that at which the recorder can write the data. This means it is possible for an internal buffer to be unable to accept any more data. This can lead to a situation where the CD/DVD-ROM drive has already read audio data in its internal buffer (cache) but has not yet been able to "deliver" to the burning program because the buffer is full. This means that the CD/DVD-ROM is forced to reposition the reading head. As the CD is turning continuously in the CD-ROM/DVD drive, the reading head has to jump back to a previous position. 
Many CD/DVD-ROM drives cannot adjust the reading head for audio CDs accurately and therefore sometimes invalid audio data is transmitted.

So, the lesson from all this "techno-talk" is to keep the burn speed LOW if you require accurate, high quality disc copies.


POSTAGE - Shipping
Do take note of the
cost saving in postage when ordering two or more sets. 
Four x 2CD sets  or  Two x 3CD  sets comes in at just under
500gm and costs $23 in shipping to Europe.
A single  2CD set costs the same to mail !!
To order  four sets singly could cost over $76 in postage !
I try to keep postage costs to the minimum and there is no inflation of the total cost at this point.

Unfortunately, large packages have a way of never reaching their destination, especially to some countries!  Airmail delivery to most countries should never take more than three weeks and if it hasn't arrived in that time you can probably consider it as lost or continue to wait patiently and hope.
That is extremely frustrating both for you and for me.
So please give some thought to structuring your order so that it can be sent in a convenient package.    For example:   2 x Box Sets 
OR...
                                            1 x Box Set  +  2 x 2CD 
OR ...
                                            4 x 2CD     ......  
                                            these combinations can take advantage of the
500gm weight step.
The next weight step is  1000gm  with a significant increase in cost.  ($42)
Certain countries are extremely unreliable in their delivery systems so if you are aware of postal delivery problems,  please take the Registered Post  Rate 
The cost of this is:
                              ... up to     500gm  $27
Over  500gm          ... up to    1000gm  $49  ...   e.g.  1 box set plus  3 x  2CD is just over 500gm.
                        
Check with me if you are uncertain about your packaging combination 
and want to ensure a cost effective one.

This method provides tracking of your parcel and at least returns the major costs involved should it fail to arrive. 
I can not replace items that fail to reach their destination through no fault of mine.

Celestial Audio is a part-time business so please do not anticipate immediate shipments.
However, if you have not heard anything about your order after four weeks and it has not been billed, please enquire about your order status.


Available from Celestial Audio:

         
Cardboard  CD mailer which will hold
  up to 4 x 2CD sets.
Provides firm and secure packaging.
Available in lots of 25 ($10)   or  50 ($18)  plus freight.
Please email for further details:   contact@celestialaudio.com.au


Useful links
:

For recording to the computer:
http://www.hitsquad.com/smm/programs/TotalRecorder/

To create  Audio-DVDs:
http://www.audio-dvd-creator.com/

To extract digital audio from a DVD:
http://www.castudio.org/dvdaudioextractor/