Remember those legends about ‘digital recording on VCRs’ back in the 80’s??

As a kid, before the DAT deck was available, I vaguely remember talk about ‘so and so mixes his music digitally to a VCR’ and this just sounded like some black magic to me. Well, as it turns out, this was done via a reasonably affordable series of SONY devices, the base model of which was the 501 ES. The 501 ES was a duplex AD/DA convertor that could covert stereo analog audio to a single PCM stream that was then sent out as a video-bandwidth signal, to be recorded as single video signal on any VCR deck. There were some real drawbacks, such as a 1/2 sample interchannel delay, and apparently it worked best in 14 bit, rather than 16 bit mode? But none-the-less, this was a ‘real thing’ and back in those days, DIGITAL WAS BETTER and any way that you could GET DIGITAL was pretty much embraced.

Now, SONY actually marketed this technology as early as 1978, but at that point it was extremely expensive and beyond the reach of a small studio or musician. We ran an article on that first machine, the SONY PCM-1, a long while back. You can read it at this link. The PCM 501-es was much more of a prosumer product, though, so it managed to achieve much wider use. I found a great article from a 1986 issue of MUSICIAN mag which explains, in great detail, operation of the 501ES. It is by a person or persons named FREFF, and I reproduce it below for your edification.

chris

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Tom Fine says:

12/26/2013 at 3:00 pm

Hey Chris: Thanks for the article.

Using videotape for storage of digital audio data dates from the 1960s, pioneered by Japan broadcaster NHK and then further advanced by NHK and Denon. Denon was first to produce commercially-released LPs from digital masters. Videotape machines were the storage systems for the proprietary Decca and EMI digital recorders in the UK. The main reason that 44.1/16-bit was the agreed CD standard is that it can be stored in the frame rates of Japanese and US video recorders, made by Sony. Remember that the Soundstream, 3M/BBC and Decca digital recorders could all do more resolution than 44.1/16 from the get-go. For the first two decades of CDs, the typical go-to mastering/authoring system was a Sony U-Matic based setup, the 1600, 1630 or last-generation systems. JVC also had a U-Matic-based CD mastering/editing/authoring system.

For more, see my article "The Dawn of Commercial Digital Recording," originally published in the ARSC Journal:
http://www.aes.org/aeshc/pdf/fine_dawn-of-digital.pdf

Regarding the Sony 501ES -- it's a neat artifact. This was part of what would be third-generation VCR-adapters from Sony (PCM-1 was first, then PCM-F1). The standard used is the EIAJ format, which can be 14-bit or 16-bit, 44.1 kHz sampling rate. The 14-bit was usually preferred with consumer VCR's because the error-correction was more robust. People using U-Matic decks tended to use 16-bit. I used to use a 501ES and a VHS deck to time-shift radio programs (this was before the age of podcasts). Leave the tuner and 501ES on, set the VCR timer and record the program unattended.

Despite claims from the day, most people would prefer the sound of a master made on an Ampex ATR-100 or Studer A80 to anything made with an EIAJ system and a VCR. However, the VCR-digital systems definitely smoked the likes of portable cassette recorders of the day.

-- Tom Fine
Carl says:

12/30/2013 at 8:32 am

That's a blast from the past. At the public station I worked at, these things were the bridge between analog and the first Sony portable DATs. We initially used them for location recordings because the adapter and a VHS machine were much lighter to carry into a venue than an Ampex ATR-700. We lashed them together with gaff tape. The tape was lighter and cheaper, too, and given the trade offs the sound compared well to 7.5 ips analog. As a hedge against dropouts, we also ran analog into the vcr's audio tracks, but I don't recall ever having to use them. I had a few musicians complain about the steely, bleached sound, but most artists were happy to get free recordings, so they accepted it. These boxes were hacked; Keith Johnson's modded 701 made some very good sounding recordings for the audiophile label Reference Recordings.
- Tom Fine says:
  
  12/30/2013 at 11:23 am
  
  There is some information about Keith Johnson's modified 701 here:
  http://www.ultraaudio.com/features/20090201.htm
  
  Here is a somewhat fuzzy photo of the service manual cover:
  http://elektrotanya.com/PREVIEWS/63463243/23432455/sony/sony_pcm_701es.pdf_1.png
  
  This page has some good images of a 701 that was for sale:
  http://www.audioscope.net/sony-pcm701es-p-1215.html?language=de
  
  I think the 701 was the last generation Sony adapter for VCR's using composite NTSC video as the carrier. Like the 601, it had a built-in SPDIF adapter, so one can get direct PCM output from the box.
  
  Carl, when you were doing radio remotes with a 501 and VHS machine, how were you operating? My guess is 14-bit and 2-hour (SP) mode? Doing backup audio on the analog VHS tracks was common. This eventually led to people just using the VHS-HiFi tracks and not bothering with a bulky and balky digital adapter. The VHS-HiFi tracks were analog FM, and could be quite balky machine-to-machine. I made a few party tapes this way back in the day, and they worked fine as long as played back on the machine they were recorded on.
  
  -- Tom Fine
  - Carl says:
    
    12/31/2013 at 10:02 am
    
    Interesting article. I have a couple of Sandiford's Delos CDs. Don't ask me why...
    
    Yeah, 14bit/SP gave us the time and reliability needed. There was always the attitude that this was 'only' FM radio, so ultimate quality was not a priority. To me, getting away from the remote truck and into portable systems meant freedom from compressor/limiters, which some engineers couldn't work without.
Tonmeister K. says:

01/16/2014 at 3:20 am

Hiya. Dug up the old Sony pcm-f1 today. Hooked it up to the Sony sl-hf 900 beta machine. Yeah, the old tapes played back perfectly both as Beta hi-fi, and 14/16 bit digital recordings. The latter DAT technology, tho' better, was not as robust. Cheers.
Andrew says:

05/21/2014 at 10:53 pm

I use VHS as an outboard effect on drums and vocals, it has a nice wet effect that's a step above dumping to cassette and I use the pitch control to further mess around.

To hear a similar VHS used this way listen to Mac demarco's first record
Giro says:

10/31/2017 at 7:32 pm

The 701 ES is among the simplest and probably makes the best sounding PCM destined for low rate mediums, because its an inherently causal system. Newer designs are inherently non-causal because designers 'gave in' to linearity (at low rates at first) and pressures from their superiors to make things cheaper. Non linearities imposed by causal analog filters aren't even audible, irrespective of rate because it is an intra-channel phenomenon, and this is well documented. Increasing the rate of a PCM adapter can mitigate the problems of aliasing up the khz. The main propellants to over sample is cost effectiveness (relative to SNR) and linearity. Oversampling is fundamentally flawed. The system was to aid and 'divert' problems associated with low rate systems. consider the objective of linearity, at low rates, this introduces pre-ringing which is unwanted - so - the alternative would be to program OS systems to be minimum phase instead, which completely undermines its purpose! SO, logic would say, the next best route is to go back to 1fs systems (these adapters) increase their rate seen by the double-ended system (that was the CD system initially) as advances in storage is much more accessible and and affordable than then. This seems like the obvious and natural next step however manufacturers just aren't interested and I fear that this is because of the cost element. SAR technology is a bit more expensive but sounds hella great. I also think that this has something to do with the fact that the devices are inherently 'weighted' with respect to current, much like valves are.
john morris says:

07/05/2018 at 6:52 pm

Back in May of 1989 I purchased the Toshiba DX900C. It was the flagship HI-FI VCR of the company and it had a 14 bit PCM processor in it. It was only $1300 but boy was it worth it.
It actually allowed 4 tracks of professional quality audio at the same time. With four inputs and four outputs you could record 2 tracks of PCM and 2 tracks of Hi-Fi (AFM) at once. Great for backing up 4 track cassettes. You could use the EP mode and get 8 hours of CD quality (minus 2 bits) on a single T-160. These would play without problems....For about 2 years. Always record on the fastest speed. But even on the SP mode my PCM tapes could be played back 5 years later. unfortunately I mixed my 4 track cassette mixes down to this machine on the slowest speed . I later saved these mixes by copying to VHS HI-FI in the SP mode. And then when those were in danger I copied them to VHS HI-FI again. In 2003 I took the third generation copy and put it on CD.

I remember being so impressed with the digital sound. It was my first digital recorder.
Johnnie V says:

08/16/2018 at 10:03 am

I was just wondering if someone here could point me in the right direction. I recorded a single with my band back in the late 80's- early 90's. I have the master on a Betamax tape. This was recorded on a Sony PCM 501 to Betamax. I cannot seem to find anyone that is able to convert these tracks over to digital. I do not have any duplicate recordings of this song and would really love to hear it again for nostalgia purposes. Can anyone point me in the right direction to someone or some company that could make this happen?