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78 RPM's :

Restoring old 78 rpm's is rather a special case. To do it well, one should dispose of an adequate equipment.
But we will manage with what we have.

The really old records (1910-1930) where made, having in mind that they where to be read by with mechanical / acoustical systems. That is to say, a table turning between 76 and 82 rpm, and a needle made out of steel or bamboo wood jointly fixed to a membrane which was in turn joined to a acoustical impedance converter leading out into a horn. A cleverly placed "3D hinge" separated the "tone arm " consisting of the "needle-converter-beginning of the horn" from the rest of the horn. This tone arm applied on the record a weight of about 100 grammes. The needle had to be changed after listening to one side of the record.

The frequency response of such a system was not linear.The high notes decreased. On the other hand, the mechanical (and electro-mechanical) systems introduced also a non linear response when the disks where cut. The level of the low notes decreasd and the higher tones increased. These two non linear behaviours tended to compensate one for each other resulting in a more linear frequency response.
The decrease of the lower notes had a certain advantage. The groove was less wide (or deep) and allowed to put more music on the side of a record.

Later, piezo-electric sound heads where invented. These heads also did not have a linear response. The connection of the saphir and the sensistive crystal was quite rigid and there was a decrease in the treble response. Do you remember those old valve record players (Teppaz and others ...) which used two styluses on the same head to read both LP's and 78 rpm's ? There was no R.I.A.A. correcting preamp but the resulting sound was satisfactory even if it was not up to today's HiFi standards.

The use of moving coil sound heads to read 78 rpm's presented a problem. These heads could be very light and linear and of great quality but they did not compensate the non linear recordings. It was then that a new standard was born : the electronic R.I.A.A. correction. This was applied in two ways. The first was during the cutting of the record ( decrease of bass and increase of treble). The second way was during the restitution of the music ( increase of bass and decrease of treble ).

Before this standard, there where many correcting curves applied in the making of records. As many as there were record makers. But all these curves where very similar to the R.I.A.A. curve.

With your modern and everyone's actual equipment ( magnetic head ) you can and should use your R.I.A.A. preamp to transfer 78 rpm music to your computer. I know, this is the opposite to what many people say , but they forget several things :

    - All you want to do is to please your grand mother and transfer her 78 rpm collection on to CDR (or even audio cassettes). This will enable her to remember her youth after listening to this music that she can't play any more. Her old gramophone died 40 years ago.

    - With Cool Edit 2000 you fiddle with the frequency response directly on the digital file. You can then manage a tonal balance which can be satisfactory.

    - You can also, up to certain point, get rid of the clicks and noises usually found on these old records.

    - In this specific case the obtention of HIFI is not compulsory.

The most delicat point is the type of stylus that you are using. One should really buy a special 78 rpm stylus and adapt it to your sound head. Several web sites specialize in the commercial side of these things. The actual LP stylus is too small for the 78 rpm grooves and it has a big tendancy of picking a lot of surface noise. But it is all the same possible to use a modern stylus if the record is not too worn out.
If it is possible, use a spherical model

And what about the turntable? Mine only works at 45 and 33 1/3 rpm !

No problem !!     There is a trick !

One has to adjust the sample rate. Put the 78 rpm record on a player mechanically adjusted at 45 rpm.

     - New
- Check "Stereo" and "16 bits and make the " Sample rate "at ;   25442
     - Ok

Why 25442 ?    because   :  44100 x 45 / 78 = 25442

For a 80 rpm we would have   : 44100 x 45 / 80 = 24806

Record your 78rpm (or 80 rpm) at the speed of 45 rpm.
The music will too low in tone and too slow.

Restablish the situation by :
     - Edit
     - Adjust Sample Rate

Choose " 44100 "

Save the file. It will be at the right speed and tone.

The fact of reading your 78 rpm thru an R.I.A.A. preamp at 45 rpm contributes to establish a tonal balance that you would not have had if you had read it mechanically at 78 rpm.

In the following example, the only correcting made on the adjusted at 44100 Hz file was some "click removing". This is just to show that it is possible to get some decent results without excessive work.
( The stylus used was spherical and made for LP's )

Sampled at 25442 Hz
(mp3 de 204 Koct.)
Adjusted at 44100 Hz
(mp3 de 236 Koct.)

Use of the same technic for transfering music from this very worn out 78 rpm of the 20's.

Tea for two
(mp3 de 118 Koct.)

16.66 RPM's :

Put the 16.66 rpm record on a player mechanically adjusted at 33.33 rpm.

     - New
- Check "Stereo" and "16 bits and make the " Sample rate "at    88226
     - Ok

Why 88226 ?    Because   :  44100 x 33.33 / 16.66 = 88226
(This will only apply if your sound card is able to sample higher than 44.1 Khz that is to say in general 96 Khz)

Record your 16.66 rpm at the speed of 33.33 rpm.
The music will too high in tone and too fast.

Restablish the situation by :
     - Edit
     - Adjust Sample Rate

Choose" 44100 "

Save the file. It will be at the right speed and tone.

In this case if you have used your R.I.A.A. preamp for too higher frequencies coming out of your sound head, you will have to correct your general frequency response by decreasing treble and increasing bass.

If you have no 16.2/3 rpm's or 78 rpm's, you can also experiment this method by placing a 33.1/3 rpm record on a 45 rpm turntable and sampling at 44100 Hz x 45/33.33 = 59541 Hz.
(This will only apply if your sound card is able to sample higher than 44.1 Khz that is to say in general 96 Khz)

Or the other way around, place a 45 rpm on a 33.1/3 rpm turntable and sample at 44100 Hz x 33.33 / 45 = 32663 Hz.

Noise reduction :

Noise reduction systems are very usefull when transfering audio tapes to CDR.
They allow a good removal of "Hiss".
But they must be used parsimoniously with records. They are very difficult to adjust.

In this example, ( NOT TO BE FOLLOWED ) the musical distorsion is desastrous.

Before noise reduction
(88 Koct.   mp3)
After noise reduction
(88 Koct.   mp3)