Turtlerock Forum

I need to access a 1 inch 8 track needed for a Bon Scott recording that was recorded just before ACDC was formed.
Needs to be transferred to wav files at 48khz
This is for a mate of mine who wants to be at the transfer session, and would prefer to do it in Sydney.
Tape has been already baked at 301
Can anyone help please?
Thanks

Hey Chris,

email me, i have a 1" 8 track (ampex ag440b)

Chris

YEAH - AMPEX - could not get any better
I'll email you chris
Thanks

i have worked this track previously many many years ago
but we fatally made safeties to DAT
.. so much for digital !

its a good tune !
round and round

Ahh - good old Dats
I remember at Spectrum Films we transferred literally thousand and thousands of 1/4 inch film sound FX library's from 50 years worth of location recordings, atmospheres, spot FX, etc to VHS digital thinking it was the future storage medium - then 10 years later it was done again to DAT when it first came out. (most of which are now dead)
The boss told my sound editor mate - you can have all that old shitty 1/4 inch tape now that DATS have been invented.
The 1/4 tapes all still sound good - and have recently been transferred once again to hard disc.....to die maybe once again.
Nothing like rust on plastic.

I remember reading comments made by an archivist at the Powerhouse Museum regarding the limitations of digital storage media compared to correctly stored tape

Last time I was at the Film and Sound archives, digital storage was a hot topic. Their solution, at least then, was to do a digital to digital re-store every 5 years. If a new system had been developed in that time, then they would re-store to that, if not then a re-store to a new copy in the previous format. Of course this only works if you believe that there is no copy loss in digital.

So how (where? what conditions?) do you store tape to make it last?

I recently looked at a heap of 15 year old videotapes and they're shedding so much oxide that I had to clean the heads every couple of minutes ...

stosostu wrote:Last time I was at the Film and Sound archives, digital storage was a hot topic. Their solution, at least then, was to do a digital to digital re-store every 5 years. If a new system had been developed in that time, then they would re-store to that, if not then a re-store to a new copy in the previous format. Of course this only works if you believe that there is no copy loss in digital.

............A bit like painting the Sydney Harbor Bridge. Once you finish you go back to the start and do it all over again.

It's a matter of fact, not faith...

stosostu wrote:Of course this only works if you believe that there is no copy loss in digital.

well technically with digital pcm data
there is always errors on playback or copy = loss

but really the size of the loss is not worth the mention .. unless somebody mentions it


now that am afraid is fact.... not faith

be careful with this 0 and 1 argument i reckon

its been simplified for digestion - not for reality

i have a theorectical "no loss" DA convertor
have you seen how big it is ..?
its not exactly practical or affordable ... but it exists
and even then its still only statistically no loss !

as for the bon scott track , i transferred it to digital 15 years ago
now all those 0 and 1 have gone missing off the media !

so its retransfer time again from the analog tape that has lasted since about 1971

enjoy the rich melodies of life when you hear them thats my advice

I worked on a lot of transfers for Screensound (National Film & Sound Archives) and everything including cassette sources went simultaneously to both 24bit broadcast wavs (for metadata cataloguing) and – yep – direct to 1/4" half track with a custom Otari MX55, 15ips, IEC EQ, Hx Pro and some ridiculous ref flux level – all as per their stringent specs. Any dropouts on analogue ≠ total data loss.

I suspect all those bwfs will, if not already, need transferring from optical disc to HDD and/or SSD, or Fortress of Solitude crystals. And in triplicate.

"well technically with digital pcm data
there is always errors on playback or copy = loss"

you sure about this Rick? This would imply that all data stored on a hard drive always has errors. So how come all my spreadsheets work and my applications still work as it would be fair to say that any uncorrectable bit would in all likelyhood cause a software or data file to crash. We know that magnetic and optical storage does have errors but that error correction built into the dataset is there to correct these. Of course you occasionally can get uncorrectable errors but wether a spreadsheet or an audio file these are obvious as defective.

If I took a PCM wavefile and made a million copies of copies would I end up with the same file?

Yes, it's been done. The whole piracy thing would be an issue if it didn't work...

rob wrote:If I took a PCM wavefile and made a million copies of copies would I end up with the same file?

You can lead a horse to drink but you can't make it water

CD's have a tolerance for errors. My understanding of it is you don't need a bit for bit reproduction on a CD for it to contain data that is still viable. An audible CD "skip" is when the number of errors cross a particular error threshold for example.

Now I guess the question remains (if I am correct in any way, shape or form that is!) as to whether the platters in a harddrive are similar? There would have to be a degradation of quality... we are talking about light pitting a fine aluminium (or gold) film after all. Straight duplication might lead to negligible differences as the computer only needs to read the two distinct states of high and low voltage. It can probably accumulate though.

Hi,

I think you'll find that there is quite a bit of mathematics going on inside hard drives in the form of error correction via checksums and the like.

I remember typing machine code for games into a commodore 64, with each row having an associated 'checksum' to make sure the line you just typed in was correct. Ah those were the days! I'd imagine hard drives do a similar thing on a much more advanced scale.

Optical media for playback - on the other hand, can have errors and still 'play'. I think the very nature of optical media lends itself to a certain number of errors. Data stored on optical discs I think is layered differently, rather than being just a linear stream of data it's actually got checksums and error manipulation built into it.

Any 'experts' out there?

Chris

Sammas wrote:CD's have a tolerance for errors. My understanding of it is you don't need a bit for bit reproduction on a CD for it to contain data that is still viable. An audible CD "skip" is when the number of errors cross a particular error threshold for example.

Not only do they have checksums and parity bits, but the "samples", such as they are encoded, are placed out of order. It's known as Cross-Interleaved Reed-Solomon Coding and reduces the likelihood that consecutive samples will be lost.

Hmmm, Interesing stuff.