QCASS: Astrocom Model 307 Quadraphonic Cassette Deck

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Quadrockasaurus

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Please post comments and photos of this quadraphonic cassette deck in this thread.

Astrocom Model 307 Quadraphonic Cassette Deck (1972)


Rarity: ULTRA RARE
Average Sale Price: UNKNOWN


Front View
Astrocom Model 307 Quadraphonic Cassette Deck.JPG
 
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Holy shit!

Few questions:

1. Is it yours?
2. If not, Have you ever seen one in person?
3. How did you find out about this one?

This could be the ULTIMATE way to preserve the quad recordings (in an analog format of course). Especially the Q8 and Q4 tapes
 
In answer to your questions...

1. Not Mine.
2. Never seen one in person or ever seen one for sale in the usual places.
3. Image is from a 1972 roundup of Quad components in an old Playboy mag, where I found it, and could not believe that there was actually a Quad cassette deck available in the early 70's.

I believe Astrocom was an American company, and the unit might have been assembled in the US as well.

Cheers.
 
Quad Linda...Thanks for this enlightening new info....I always wondered why I'd never seen one of these units for sale.

I also have an image of a (equally mysterious...or not) Astrocom/Marlux Quadraphonic Reel to Reel, if I can scrounge enough cash together to replace my recently kaput scanner, I'll add that to the hardware database at some point as well...:)
 
The reel-to-reel is a new one to me. I wasn't aware there was a prototype or production reel. Would love to see the picture. Of the 7 chains and dozens of independent dealers doing business in Chicago and Milwaukee at that time, I don't recall anyone being an Astrocom/Marlux dealer.

Is your scanner for police calls or inputting documents into your computer?

Linda

"You're under arrest, you have the right to one phone call, or remain silent, so you better shut up!" - Miles Davis on the cover of "You're Under Arrest." Sony Japan SACD (2ch) SRGS 4530.

Quad Linda...Thanks for this enlightening new info....I always wondered why I'd never seen one of these units for sale.

I also have an image of a (equally mysterious...or not) Astrocom/Marlux Quadraphonic Reel to Reel, if I can scrounge enough cash together to replace my recently kaput scanner, I'll add that to the hardware database at some point as well...:)
 
...for anyone interested, here is the complete 1972 Quad roundup page where I found the (..prototype..??) Astrocom 307. Note they had a price set and everything....and the text mentions the unit records in 2 & 4 channels with playback of regular cassette PLUS auto reverse! playback of stereo cassettes.

...(...if it worked) you really got you money's worth for $499.95..!!

1972 Quad Roundup Page.jpg
 
Philips 'main' idea for a 4 channel Compact Cassette was to use a 4-4-4 compatibility matrix like CD-4 used, so that both mono and stereo cassette decks would play back all the channels. Unfortunately, the tapes would have played only in one direction for half the total time - and adding tracks together add's noise and Dolby B didn't provide enough noise reduction to offset the increase in going to quad. The other option they considered was splitting each mono track into two, making the cassette an 8-track medium, but the tracks would be so narrow that the noise increase would have been terrible, in addition to the difficulties in making recording/playback heads accurately with such small dimensions. And a 4-2-4 matrix was out of the question because the cassette format couldn't hold phase and level between channels accurately enough to decode properly. So, Philips simply refused to license any companies from making 'non-standard' (i.e. quad) Compact Cassette decks. This didn't apply to cassette units like the Teac multi-track PortaStudio's (is that the correct name?) because their tapes were never meant to be compatible with existing consumer gear.
 
Six years on and although none of these has ever shown up since then - the JVC version from 1974 did a blowby on one of the electronics museum excess-gear websites this summer (vs eBay/Amazon) for $250.

As previously noted - the cassette portastudios - whether 4-track or 8-track - were NOT like their reel-to-reel counterparts.

As everybody knows by now - Q8s and portastudio 8-track quarter inch are compatible when it comes to track placement where the cassette version is not.

Even though the speed and EQ is not compatible - both of which have been corrected on a one-to-one basis by a number of guys both on as well as off this board for the purpose of REPRODUCING a Q8 to record into the computer - nobody to my knowledge has ever done recording onto it.

Well not in real time anyway. When I want to putz with newbies minds, I take whatever stereo source somebody has - run it through my QSD-10 decoder - make a half-inch 7-1/2 IPS 4-track 10-1/2-inch quad master reel out of each ``side'' of the album and then dub that at 30 onto loop tape with the e.g. Fostex or Tascam's 15 with the NAB curve re-tweaked on the record deck.

Then reproduce the album art and cartridge back with some design software, print out on some glassine paper - stick it on the cart wind the tape into an old Q8 shell snap it shut and voila. e.g. Maroon 5 or Nickelback on Q8. (ROFLMAO)
The Astocom Marlux, was a cassette with eight tracks, four in each direction. Those would be compatible with stereo and mono cassette machines where a cassette recorded on the four track studio deck would play only two tracks on other cassette machines, similar to playing a Q8 on a stereo 8 deck.
Well not quite.
The tape would only be marginally compatible.
As everybody also knows by now - the cassette portastudios - like the half-speed Talking Books for the Blind and the 3/4 speed background music cassettes both of which use four monaural tracks two in each direction - use equidistant tracks.

Take one and play it on a portastudio and see. You'll hear four individual tracks - two forward and two backward - perfect fidelity half-speed speech at 15/16 IPS and the same for the background music tapes at 1 13/16 (halfway between 15/16 and 1-7/8 so they could get an hour on a side of a C-90 chrome cassette.)

The quadraphonic versions on the other hand - both the single direction as well as dual-direction formats - use a wide-center-guardband format so that you would theoretically be able to play at least the two-sided versions on a standard stereo cassette player and not miss anything.

The single direction versions with the notches in the back and the buttons over the holes like a data cassette would have in order to ensure proper tape orientation - would indeed play back as a Q8 would on a stereo player - front tracks taking up Side A and rear tracks taking up Side B.

The handful of times I had to transfer these types of single-direction programs that I couldn't source elsewhere - I had two oprions.

First was to take the transport out of an old Child Guidance or Worlds of Wonder 4-track cassette and quiz book player and pipe that directly through to the Head In of one of my old 4-channel reel to reel players that had the feature and record onto another 4-channel reel player from there (or a portastudio at 3-3/4) or later on I had to take it to church/school and run them off onto a standard 4-track reel dubber.

I had to re-patch the cassette to be the master and the reel to be the slave - and then stop them both down from 60 for the reel and 15 for the cassette to 15 for the reel and 3-3/4 for the cassette and then do the actual transfer off that.

Which only worked because the cassette-from-reel dubber at church/school was configured for consumer stereo track configuration - dubbing Side A and Side B simultaneously.

It wasn't bad once I switched the reel-slave tape to BASF LPR-35 CR and switched on the Dolby encoding. Better than a commercial 3-3/4 dub from a record company but not as good as the 7-1/2 versions.

When people HAD portastudios and whoever they were giving the copies to also had them - I started scouring around for the CG tapes w the notch in the back and the buttons over the holes the same as the old data cassettes from the 70s had and dubbed onto there.

Then as the years went by and computers became first accessible then affordable, we popped that into the computer and tried to clean it up the best we could. Not perfect - but serviceable.

As far as archiving quad material on portastudio tape - at least there were millions of portastudios made so it's not like you aren't going to be able to come across a working one or make one out of three or four.

Or - there's always ordering a one-off and paying the money to John French who has all the patents schematics and tolerances for any number of odd-format heads and mounting THAT in a 4-track or 8-track cassette portastudio.
 
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There's some misinformation here I thought I would clear up. According to Walter G. Salm's Cassette Tape Recorders How They Work - Care & Repair (1973) Astrocom/Marlux's format was essentially the same as your home four track Portastudio recorders; four tracks in one direction. From top to bottom Salm has the track order as RB, LB, RF, LF. As mentioned above, this didn't sit well with Philips which is why they proposed their eight track quad cassette format with a full quad program on each side. AFAIK, the 307 was just a prototype and never made its way to the masses.
 
Mea Culpa! I stand corrected. Must be a brain fart. At 66, I'm entitled, aren't I? In addition, I'm not sure that I ever returned to this thread until today...

After reading my original post, I realize that it makes no sense. It contradicts itself. So, it is now deleted.

As Nick mentioned, I do recall JVC working on a similar deck. I vaguely recall ('74 ??) seeing it in a JVC brochure, but never in person. And JVC's midwest HQ was in the next 'burb from our store. So, we got to see new products when they first hit the street. We could fill special orders instantly if we drove over annd picked it up.

The late, great Ty (Disclord) has a wonderful post, as well. I recommend you (re)read Nick's and Ty's posts. Ty's knowledge and insights into matrix hardware/software (+more) was astounding! He was involved in the design and beta testing of the Surround Master. His input was invaluable. RIP, Ty.
 
Philips 'main' idea for a 4 channel Compact Cassette was to use a 4-4-4 compatibility matrix like CD-4 used, so that both mono and stereo cassette decks would play back all the channels. Unfortunately, the tapes would have played only in one direction for half the total time - and adding tracks together add's noise and Dolby B didn't provide enough noise reduction to offset the increase in going to quad. The other option they considered was splitting each mono track into two, making the cassette an 8-track medium, but the tracks would be so narrow that the noise increase would have been terrible, in addition to the difficulties in making recording/playback heads accurately with such small dimensions. And a 4-2-4 matrix was out of the question because the cassette format couldn't hold phase and level between channels accurately enough to decode properly. So, Philips simply refused to license any companies from making 'non-standard' (i.e. quad) Compact Cassette decks. This didn't apply to cassette units like the Teac multi-track PortaStudio's (is that the correct name?) because their tapes were never meant to be compatible with existing consumer gear.
Philips' insistence that all cassettes be compatible with all players, and their patents that assured this, killed the idea of a discrete quad cassette. When you look at the track layout they'd require, and how narrow those tracks would have to be, keeping proper head alignment would be tricky. Also, how effective could Dolby B or C be on such narrow tracks? I would have loved to have seen a discrete quad cassette deck, but it wasn't in the cards.
 
Mea Culpa! I stand corrected. Must be a brain fart. At 66, I'm entitled, aren't I? In addition, I'm not sure that I ever returned to this thread until today...

After reading my original post, I realize that it makes no sense. It contradicts itself. So, it is now deleted.

As Nick mentioned, I do recall JVC working on a similar deck. I vaguely recall ('74 ??) seeing it in a JVC brochure, but never in person. And JVC's midwest HQ was in the next 'burb from our store. So, we got to see new products when they first hit the street. We could fill special orders instantly if we drove over annd picked it up.

The late, great Ty (Disclord) has a wonderful post, as well. I recommend you (re)read Nick's and Ty's posts. Ty's knowledge and insights into matrix hardware/software (+more) was astounding! He was involved in the design and beta testing of the Surround Master. His input was invaluable. RIP, Ty.


4 adopt 4ch cassette in Japan ,

is the article headlining the existence of quad cassette players/recorders.

Aiwa , Hitachi , Matsushita and JVC demo'd prototypes , with Hitachi's actual prototype still pending.

BILLBOARD...28-07-73 Page #33.
 
From my post in Tapeheads.net:
http://www.tapeheads.net/showpost.php?p=461097&postcount=3
Specs seem typical of 1972 vintage cassette machines, maybe Philips
and Dolby thought the cassette medium in 1972 was too fragile to
reliably support 8 tracks on the narrow cassette tape.


Kirk Bayne
Philips' intention was that any cassette recording was to be fully compatible with any cassette player. Any variation from that violated the patent and licensing agreements. This Audax deck may have been set up to use all four tracks in one direction, like an open reel tape. If so, it would have gone against the patent and licensing agreements, and Philip's could have prevented it from being marketed.
 
From my post in Tapeheads.net:
http://www.tapeheads.net/showpost.php?p=461097&postcount=3
Specs seem typical of 1972 vintage cassette machines, maybe Philips
and Dolby thought the cassette medium in 1972 was too fragile to
reliably support 8 tracks on the narrow cassette tape.


Kirk Bayne
Any tape deck with a s/n ratio of just 46 dB would be barely useable as a dictating machine - any hifi aspirations for such a device would be laughable!
 
IIRC, there's about a 3dB loss in S/N due to the (quad) magnetic tracks
being 1/2 the width of the stereo magnetic tracks on the cassettes.

The S/N spec is most likely before Dolby B NR.

JVC marketed cassette decks with (Dolby B compatible) ANRS
in the early 1970s.

I wonder if Astrocom had used ANRS instead Dolby B if this
Discrete Quad cassette system could have been brought to market
(it did meet the Philips requirement of backward compatibility
with stereo and mono).


Kirk Bayne
 
Mea Culpa! I stand corrected. Must be a brain fart. At 66, I'm entitled, aren't I? In addition, I'm not sure that I ever returned to this thread until today...

After reading my original post, I realize that it makes no sense. It contradicts itself. So, it is now deleted.

As Nick mentioned, I do recall JVC working on a similar deck. I vaguely recall ('74 ??) seeing it in a JVC brochure, but never in person. And JVC's midwest HQ was in the next 'burb from our store. So, we got to see new products when they first hit the street. We could fill special orders instantly if we drove over annd picked it up.

The late, great Ty (Disclord) has a wonderful post, as well. I recommend you (re)read Nick's and Ty's posts. Ty's knowledge and insights into matrix hardware/software (+more) was astounding! He was involved in the design and beta testing of the Surround Master. His input was invaluable. RIP, Ty.


Just a little more info I found in relation to the JVC Q4C deck QUAD LINDA, (via Billboard.)

"JVC quad cassette demonstrated and various quad disc systems at Polygram's Solleveld . Phonogram and Polydor have made 4 channel programs for sometime now .....still undecided. They have made test lps in CD-4 and SQ and await conditions for eventual quad releases ".
( May 26th 1973 , pages 63/64)

And in July 7th 73 , page 48 :

"Q cassette by JVC uses Cronios 4ch head . 4CD-1680 JVC Deck compatible with 2ch and mono, and can pick up 8 signals."


And one more company had a Q4C deck : ( 17-03-73 , page 29)
-" Q cassette by Nippon Columbia has matrix and discrete capability as demo'd at the A.E.S. in Rotterdam. "
 
https://worldradiohistory.com/Archi...-Review-Tape-Recording-Guide-1974.pdf#page=64^^^
Philips has repeatedly suggested that the way to four-channel cassettes must involve a further reduction of track width. Specifically, this is eight very narrow tracks all within the width of a little more than 1/8inch...


So...it was a Philips idea, I suppose that the Astrocom 307 could have allowed Dolby B for Stereo cassette recording, but not for Quad cassette recording (possibly pacifying Dolby Labs).

(My interest in Audio began with receiving a compact cassette recorder for Christmas 1969 [a Craig 2610], so I followed developments in the compact cassette format closely)


Kirk Bayne
 
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