Film-Tech Forum ARCHIVE: 6 Track Magnetic vs 6 Track Digital

my profile | my password | search | faq & rules | forum home

»	Film-Tech Forum ARCHIVE » Operations » Film Handlers' Forum » 6 Track Magnetic vs 6 Track Digital (Page 1)

This topic comprises 11 pages: 1 2 3 4 ... 9 10 11

Author

Topic: 6 Track Magnetic vs 6 Track Digital

Tom Petrov
Five Guys Lover

Posts: 1121
From: El Paso, TX
Registered: Jan 2003

posted 12-28-2010 06:32 PM

I have recently gotten into 70mm films. I am wondering if it is worth it to make it Ottawa for the 70mm festival.

A lot of the movies will have 6 track magnetic.

Wondering what people's thoughts are on this?

| IP: Logged

Mark J. Marshall
Film God

Posts: 3188
From: New Castle, DE, USA
Registered: Aug 2002

posted 12-28-2010 06:55 PM

SR has a wider frequency range and a wider dynamic range than digital. If done correctly, six tracks of SR analog will sound awesome compared to six tracks of digital. I think the only 70mm six track SR print was Star Trek 4, but I might be wrong. If they have the ability to play six tracks of SR sound and they're doing it with a great sound system, then I bet that would be pretty awesome to hear.

The rest are probably Dolby "A" or something similar and will still sound REALLY good if done right - assuming the tracks are in good shape. Lossless DTS sound should give magnetic tracks a run for their money, but I doubt that's being used.

| IP: Logged

Daniel Schulz
Master Film Handler

Posts: 387
From: Los Angeles, CA USA
Registered: Sep 2003

posted 12-28-2010 06:59 PM

I think the single best sounding thing I've ever heard was a 70mm 6-track mag print of Apocalypse Now. The print was in pristine condition, and the sound was simply glorious.

The more recent restorations have gone through a digital remix, but in the earlier days of DTS 70mm, the 6-track DTS discs were a straight transfer off the 6-track mag masters.

| IP: Logged

Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 12-28-2010 07:57 PM

What we are comparing in this topic is the difference between analog sound and digital sound in which you'll get a lot of reverbs from hi end audiophiles collectors on how analog sound is tonnage better than any digital out there.

..since you're actually hearing the entire audio waveform as it's reproduced, not scrunched into "bits and bytes" to make it come close to the actual waveform no matter how high the sampling or frequency rates are.

In short, analog is what we hear (and see) now. When you "digitize" (a.k "Tron) analog information, you're not getting the full spectrum of the original source.

You take 6 track mag audio from a 70mm print and it will blow away any digital reproduction since the encaptured wavefrom on those magnetic tracks are so spread apart due to the film speed of 20ips going across those magnetic headstack reproducers.

For recording and playback comparison: Stock analog tape studio recorders sped the tape across the headblocks at 15ips....and they were hitting 22kHz on the top end and down to 30hz with dynamics close to CD quality at around 70dB before distortion sets in .. in which this is the only thing that saves digital is that the digital can hold higher dynamics - which is over 100 plus dB -(why there is a lot more lower frequencies due to the wider dynamic range that digital can hold compared to analog), but they lose it in the top end where analog wins this area hands down.

Sadly, also with DTS processes, it chops off the HF's above 9kHz were you don't get that chop with analog.

I'll stay with a 6trk mag analog 70mm print more than a print being reproduced with DTS..

-Monte

| IP: Logged

Sam D. Chavez
Film God

Posts: 2153
From: Martinez, CA USA
Registered: Aug 2003

posted 12-28-2010 09:17 PM

I'm not sure I agree with Monte's stated numbers, but IMHO, pound for pound, 6 track 70mm mag simply sounds better than a digital version of the same material, regardless of type of noise reduction used.

We are talking of material recorded and mixed in the 60's, '70's and '80's for the most part here. Live orchestras and all the rest of the recording techniques used back then have something to do with it as well.

| IP: Logged

Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99

posted 12-28-2010 09:43 PM

If my memory serves 70mm 6 track with SR has the same dynamic range as digital and maybe a bit more namely because it will soft clip if over modulated
Also i question this 9K issue on DTS
Lawrence of Arabia had SR 70mm prints as well
a 35mm 6 track fullcoat mag has better sound than digital
the big issue over time is print though, head wear and oxide flaking and slow demagnitization of the track

| IP: Logged

Tom Petrov
Five Guys Lover

Posts: 1121
From: El Paso, TX
Registered: Jan 2003

posted 12-28-2010 09:57 PM

quote: Monte L Fullmer
between analog sound and digital sound

Wow! Its looks like older timeers have chimmed in. And that is great.

Thanks for responding. Why is it called magnetic?

| IP: Logged

Chris Slycord
Film God

Posts: 2986
From: 퍼항시, 경상푹도, South Korea
Registered: Mar 2007

posted 12-28-2010 10:27 PM

Because the soundtrack is stored on a magnetic strip? [Wink]

| IP: Logged

Ian Parfrey
Phenomenal Film Handler

Posts: 1049
From: Imbil Australia 26 deg 27' 42.66" S 152 deg 42' 23.40" E
Registered: Feb 2009

posted 12-28-2010 10:29 PM

quote: Gordon McLeod
a 35mm 6 track fullcoat mag has better sound than digital

Gordon.
Do you mean 35mm 4 track or 70mm 6 track? I may be wrong here bit I seem to recall 35mm 4 track with surround steering by tones. Can anyone verify this?

Tom.
Magnetic sound refers to actual magnetic oxide stripes applied to the film print post processing. In 70mm, these reside thus- 4 tracks in two stripes (1 stripe per side) outside the perforations and 2 tracks in two stripes inside the perforations.
Just like magnetic tape, these stripes have to be 'sounded" after the stripes have been applied, then played back to check the quality of the soundings and for Q.C. Just one reason why 70 mm mag prints are so expensive.

It seems apparent that as the volatile chemicals used in stripe application also hasten the fading of Eastman prints and possibly other manufacturers too. This volatility has also been outlawed as it is considered a pollutant and therefore there will no longer be any magnetic prints made-hence the uptake of DTS optically timecoded 70mm prints.

IMHO. NOTHING beats a well kept 70mm mag print. I remember hearing South Pacific in 70mm mag and it was stunning! Considering the recording equipment used, and at some parts over 120 separate analogue audio tracks mixed with valve technology, it just shows the care and attention to detail those engineers used to make an experience never to be forgotten.

| IP: Logged

Tom Petrov
Five Guys Lover

Posts: 1121
From: El Paso, TX
Registered: Jan 2003

posted 12-28-2010 10:41 PM

quote: Ian Parfrey
Tom.
Magnetic sound refers to actual magnetic oxide stripes applied to the film print post processing. In 70mm, these reside thus- 4 tracks in two stripes (1 stripe per side) outside the perforations and 2 tracks in two stripes inside the perforations.
Just like magnetic tape, these stripes have to be 'sounded" after the stripes have been applied, then played back to check the quality of the soundings and for Q.C. Just one reason why 70 mm mag prints are so expensive.

It seems apparent that as the volatile chemicals used in stripe application also hasten the fading of Eastman prints and possibly other manufacturers too. This volatility has also been outlawed as it is considered a pollutant and therefore there will no longer be any magnetic prints made-hence the uptake of DTS optically timecoded 70mm prints.

IMHO. NOTHING beats a well kept 70mm mag print. I remember hearing South Pacific in 70mm mag and it was stunning! Considering the recording equipment used, and at some parts over 120 separate analogue audio tracks mixed with valve technology, it just shows the care and attention to detail those engineers used to make an experience never to be forgotten.

Thanks for the elaborate write up Ian. Much appreciated! I didn't know any of this.

So it is similar to a cassette tape?

| IP: Logged

Darryl Spicer
Film God

Posts: 3250
From: Lexington, KY, USA
Registered: Dec 2000

posted 12-28-2010 10:44 PM

quote:
quote: Gordon McLeod
--------------------------------------------------------------------------------
a 35mm 6 track fullcoat mag has better sound than digital
--------------------------------------------------------------------------------

Gordon.
Do you mean 35mm 4 track or 70mm 6 track? I may be wrong here bit I seem to recall 35mm 4 track with surround steering by tones. Can anyone verify this?

I think he may be referring to the full coat magnetic on 35mm base used in Imax theaters. Full coat magnetic 35mm was also used on Cinerama and I think it had 7 tracks of sound.

| IP: Logged

Mitchell Dvoskin
Phenomenal Film Handler

Posts: 1869
From: West Milford, NJ, USA
Registered: Jan 2001

posted 12-28-2010 10:51 PM

quote: Ian Parfrey
I may be wrong here bit I seem to recall 35mm 4 track with surround steering by tones.

I am unaware of any 35mm mag stereo with surround steering, although I would not rule anything out. Many 35mm mag tracks had a tone on the surround track that caused the preamp to cut out the surround channel when present. This was done to eliminate hiss on that track, as mag stereo pre-dates Dolby by 2 decades.

| IP: Logged

Chris Slycord
Film God

Posts: 2986
From: 퍼항시, 경상푹도, South Korea
Registered: Mar 2007

posted 12-28-2010 11:02 PM

quote: Tom Petrov
So it is similar to a cassette tape?

Yes. Cassette tape is a type of magnetic tape.

| IP: Logged

Bobby Henderson
"Ask me about Trajan."

Posts: 10973
From: Lawton, OK, USA
Registered: Apr 2001

posted 12-29-2010 12:10 AM

It's not so easy to say which type of audio (analog or digital) is better. Lots of variables are involved.

Using proper recording and mastering techniques in conjunction with the best of what's currently available in technology, "digital" can handily beat the quality levels of analog.

Unfortunately, the best techniques are often not used when recording and mastering digital audio.

Movie soundtracks are often put together pretty fast. The music score, ADR, sound effects, etc. are among the very last elements produced in a movie production. Quality is going to be only so good when things are done in a hurry. Lots of canned audio effects of varying ages and quality levels are used.

With popular music the quality bar is all over the place. Most rock and dance pop music is horribly mastered. The high end of the wave form is often badly clipped and the remaining wave form dynamically compressed so everything sounds loud and punchy rather than natural and clean. This isn't a fault of digital technology. Rather it's a fault of listener ignorance and the tendency of record producers to cater to that ignorance.

I can play an old CD carefully mastered from analog material, such as the 24K gold "Ultradisc II" version of Pink Floyd's Dark Side of the Moon. None of that audio is clipped. The wave form is preserved, even though it's only in standard music CD resolution. That disc plays at a very noticeably lower volume level than just about any newer music disc I own.

Digital has weaknesses in areas like analog to digital and digital to analog signal conversion. A/D and D/A converters have greatly improved over the years. The live audio is "analog" but must be converted into digital data at some point. When the audio is played back through your speakers it has to be converted back into an analog signal so it can be amplified for the speakers.

Analog has its own weaknesses. The tape width and recording speed used are big quality factors. Lots of other variables play a part. Analog tape can stretch, "sweat," shed or just wear out over time.

Basically neither system is perfect. Both analog and digital audio can sound exceptional or horrible.

With either digital or analog audio sources, the sound system itself plays a giant part in determining audio quality.

quote: Mark J. Marshall
SR has a wider frequency range and a wider dynamic range than digital.

Dolby SR magnetic has a wider dynamic range than 16-bit digital. But it doesn't have a greater dynamic range than 24-bit digital.

Bit word length is one quality factor with digital. Sample rate is another.

Music CD supports 16-bit depth with 44,100 16-bit samples per second. Most movie discs have audio running at 48,000 samples per second, often in 20-bit or 24-bit sample depths. Blu-ray commonly delivers lossless 24/48 audio but can also deliver up to 8 channels of 24-bit 96kHz audio or even 2 channles of 24-bit 192kHz audio.

The combination of increased bit depth and sample rates can smooth out any of the harshness associated with digital audio. The audio creators just have to use the technology properly. Many of them aren't. They're treating digital audio the way many wannabe graphic designers are treating their fonts: disgraceful abuse.

quote: Mark J. Marshall
I think the only 70mm six track SR print was Star Trek 4, but I might be wrong.

Star Trek IV: The Voyage Home was the first movie to use 70mm Dolby SR prints. But it wasn't the only 70mm SR release. I'm pretty sure the 1989 restored version of Lawrence of Arabia had 70mm SR prints -at least it was advertised that way in New York. Indiana Jones & the Last Crusade had 70mm Dolby SR prints; I saw the one that played Loews Astor Plaza in Times Square. I thought Born on the Fourth of July sounded pretty damned good at the Ziegfeld theater. There's at least a couple dozen or so other movies released with 70mm Dolby SR prints between 1987 and into the 1990s.

| IP: Logged

Sam D. Chavez
Film God

Posts: 2153
From: Martinez, CA USA
Registered: Aug 2003

posted 12-29-2010 01:45 AM

"Wow! Its looks like older timeers have chimmed in. And that is great."

Oy!

This old tmer was lucky enough to learn the craft at a time when cinema sound was reaching the state of the art and I still make a very good and enjoyable living at this game.

IMHO, you really do come off as a total jerk if this matters to you. Thoughtless and mispelled posts do not earn much respect.

| IP: Logged

All times are Central (GMT -6:00)

This topic comprises 11 pages: 1 2 3 4 ... 9 10 11

Printer-friendly view of this topic

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.