Audio Restoration

 Shaw Sounds use Cedar Audio noise removal tools for click, crackle, hum & hiss, particularly for LP vinyl and 78 rpm records. Improvements to the overall sound can be acheived so as not to spoil the listening enjoyment, especially on very old recordings. 

Even with careful cleaning, your record will almost certainly contain unwanted interuptions, even new records contain minor clicks & pops. The degree of this interference depends very much on the overall condition of the record and it's previous use.

However, using this digital technology, it's possible to seamlessly remove 95% of these annoyances and leave you with a pure audio track. This service is not mandatory, but it is advisable unless your preference is to leave in the original 'vinyl atmosphere'.

Broadband noise can also be detected as surface noise generated by dirt and scratches in the grooves of a record or by tape deterioration and splicings. Analysis and removal such noise as electrical hum, tape hiss or machinery rumble can be acheived without removing portions of the original source material.

When restoring archive recordings, I never try to achieve a dead-silent background with the source material that is inherently noisey. While good supression of clicks, crackle and hiss are impressive, the cost is high in terms of digital artifacts and other unpleasantness. Somehow listening to a restored vintage recording with no noise at all seems out of character and wrong to the ears!

I usually like to remove as much undesirable noise as is possible with today's technology, but will never push that technology to the point where it leaves a degraded signal in it's wake.Things like digital artifacts and audio pumping are forever - once introduced into a signal, they can never be removed.

No one knows what advances in sound restoration will be made 20 years from now, and by then, the original source may not even be playable. I therefore strive for restorations that are not only enjoyable today, but remain intact for the future.

 The Concepts

There are an infinite number of processes that can affect the human perception of sound. For example, the live sound of an orchestra is dependent upon the venue, the audience and the local ambience. So what is the aim of a restoration engineer? The archival viewpoint suggests that such an engineer should present the listener with the most authentic reproduction of the original sound that can be obtained. But what about the creative influence of the recording engineer? With modern recordings, the ensemble sound often exists only on the recording medium, and many parts of it have probably never been through a microphone. Therefore the commercially minded engineer may, in contrast, attempt to generate a new recording more appropriate to its intended use. This use could be, for example, to please the public palate, or to represent accurately the sound of an era. Every restoration has its own criteria.The algorithm designer is responsible for creating the facilities by which the restoration engineer generates new recordings from old. He or she does this by developing and implementing algorithms which remove unwanted sounds and/or effects present on the old recording. CEDAR AUDIO & iZotope RX Advanced software provides a powerful set of restoration tools flexible enough to be used as the restoration engineer sees fit. However, it is always my policy that the human ear should always be the final arbiter of sound quality; judgements based upon signal processing techniques are secondary considerations.

There are times when audio requires more than just simply enhancing

An old analogue reel of tape, for example, or an LP album of which only a few vinyl copies exist; vintage material from 78's or even earlier formats. Shaw Sounds are superbly equipped to deal with such projects - we have sophisticated restoration software available including Cedar, iZotope and Steinberg Technology" with de-crackle, de-hiss, de-click and de-buzz algorithms.

We also have a full complement of vintage equipment for playback transfer quality - this has made us a respected and successful facility.We deal with all kinds of music projects from Classical to Popular, Choral to Jazz including spoken word and delicate historical archive material. We believe restoration requires great sensitivity on the part of the engineer - just because we can remove the hiss in a recording it doesn't mean we should , the recording could loose "life" or "air" as a result. Many restoration software programmes today can provide radical processing of the source signal like hiss, de-clicking & de-crackling - we at Shaw Sounds are careful not to damage the original material by over use.An intimate knowledge of our equipment and it's capabilities allows us to avoid the pitfalls of the process. An experienced engineer develops his own strategies and methods - tricks of the trade, if you like - along with an understanding of  the needs of the material, help us achieve the best possible result.

The most common requests

Removing clicks, pops and groove noise from records  ( LPs, 45s, & 78s ). 

Reducing broadband hiss from records, old reel-to-reel tapes and cassettes

Re-pitching and correcting tone inconsistencies

Making audio programmes louder, or balancing varied volumes levels

Forensic restoration.

Converting mono recordings to stereo with spatial enhancement technology.

Remastering records to CD

 Isolating particular unwanted sounds from live recordings. 

 Editing and space adjustment between programme material.

Compiling and restoring different source tracks to produce a final master CD.

Conversion of analog and digital material to different file formats. 

The CEDAR (Computer-enhanced Digital Audio Restoration) system is a commercial system for restoration of degraded recordings of all types. The system allows for real-time click, crackle, hiss, buzz and distortion removal in mono and stereo. The authors were both founding members of the company and are involved in strategic research and consultancy for the company. It should be emphasised that the algorithms and methods  employed by CEDAR are not detailed for reasons of commercial secrecy.

Transfer - Copy - Convert   LP to CD | Vinyl to CD | 78 to CD | Tape to CD | Cassette to CD | DAT to CD