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Why recordings made before 1965 sound better.

 

I’ve brought ht up this topic before, and I believe my point was misunderstood. so, I’m trying again.

Many A’goners have commented that recordings originating in the late 50’s and early 60’s which have been transferred to CDs sound particularly open with better soundstaging than those produced later.
Ray Dolby invented his noise reduction system in 1965 to eliminate what was considered annoying tape hiss transferred to records of the time. The principle was to manipulate the tonal structure so as to reduce this external noise:

“The Dolby B consumer noise-reduction system works by compressing and increasing the volume of low-level high-frequency sounds during recording and correspondingly reversing the process during playback. This high-frequency round turn reduces the audible level of tape hiss.”

‘Dolby A and C work similarly.

I maintain that recordings made prior to 1965 without Dolby sound freer and more open because the original tonal structure has not been altered and manipulated.

128x128rvpiano

Showing 2 responses by cleeds

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cleeds
5,724 posts
 
elliottbnewcombjr

... similarly 8 track cartridges, before cassettes, the ultimate piece of crap, were initially made for use in radio stations for advertisements (not much tape (i.e. less weight thus less force/abuse involved), And a moving head with serious alignment problems. But, their PORTABILITY was a revolution! 8 tracks were meant to be thrown away when that ad campaign was over ...

That is not correct. Broadcast carts are similar to 8-track cartridges but have some distinct differences. First, they run at 7.5 ips. (And some ran at 15 ips.) Unlike the 8-track, the broadcast cart has no rubber roller. Instead, the roller pivots up into the cart from the player itself, and then presses the tape against the capstan. Also unlike 8-track, tape heads are fixed in cart machine.

Most cart machines were either mono with a second track reserved for cue tones, or 2-track stereo with a third track for the cue tones. And they weren’t disposable, but were bulk erased and re-used.

The best cart machines were very, very good.

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cleeds
5,724 posts
 
bdp24

@onhwy61 has it right. Done correctly, Dolby does NOT change the original tonal structure (timbre) of instruments or vocalists. It takes the original signal and boosts the high frequencies for recording, in playback reducing the high frequencies by the same amount, thereby restoring the original tonal structure. And the hiss encoded into the recording is simultaneously reduced by the same amount, the very rationale for the Dolby process.

I absolutely agree. Dolby gets a bad rap because it was often so poorly implemented. Because of the way Dolby dynamically applies compression on a sliding band, the system requires tight calibration between the recorder and the exact tape formulation used. This includes the correct level of bias while recording to ensure a flat response. Further, the recorder and Dolby circuit must be aligned so that the tape sees the proper Dolby level. If any of these calibrations are off, the circuit can’t work properly.

Many cheap consumer recorders were so poorly made that they could not reliably maintain alignment. And many users used various tape formulations without consideration of whether they were appropriate to their decks. So results were all over the place.

I still have my Nak deck and outboard NR-200 Dolby B/C encoder/decoder. It’s amazing how good some of my old tapes can still sound. Of course it’s mostly just a novelty now.

By the way, the RIAA recording and playback curve was invented and employed in much the same way ...

Hmmm, yes and no. The RIAA curve is fixed. Dolby NR is a dynamic process.

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