BBC Matrix H

[tadploe]

Does anyone know which tracks were actually broadcast in Quad?
The follow on email I received from BBC states that their paperwork does not specify which tracks are in Matrix H, and that looks like it was a live broadcast and is not in their archive.

 

[Mark Anderson]

The mod responsible for this thread should remove it and place it in with the matrix quad album threads.
Ambisonic is not quad.

Ambisonic is the UHJ format. Matrix H and HJ are quad.
Funny to note that early nimbus vinyl records that were recorded in H and HJ and indicated as such on the cover and label can also be found with QS notations on them. They are not QS and are actually H/HJ but decoders were scarce and the format was compatible with QS. UHJ is not.

 

[fizzywiggs41]

Ambisonic is the UHJ format. Matrix H and HJ are quad.
Funny to note that early nimbus vinyl records that were recorded in H and HJ and indicated as such on the cover and label can also be found with QS notations on them. They are not QS and are actually H/HJ but decoders were scarce and the format was compatible with QS. UHJ is not.

Hopefully the moderator will remove the quad threads (H and HJ) from this Ambisonic section.

 

[fizzywiggs41]

I've taken the Radio Times every week for about fifty years (!) and I would put an enormous amount of store by it. Agreed, there are very occasional errors but it is as near 100% reliable as makes no difference. They are the oldest programmes listings in the world and since starting in 1923 they've had a fair bit of practice in getting these things right! Their Genome project is an extraordinary undertaking and a resource of enormous value - can you imagine any other broadcaster doing such a thing?

Agreed.

 

[surround.sound.enthusiast]

Sansui QSD 2 (QS Vario matrix w/ Matrix H and HJ adapter)

What do you mean by "Matrix H and HJ adapter" fizzy? The QSD-2 didn't handle Ambisonic natively, did you have one that was custom modified, or did you patch an Ambisonic decoder into the QSD somehow? You've got me curious!

 

[Soundfield]

What do you mean by "Matrix H and HJ adapter" fizzy? The QSD-2 didn't handle Ambisonic natively, did you have one that was custom modified, or did you patch an Ambisonic decoder into the QSD somehow? You've got me curious!

I don't think Fizzy said anything about the QSD-2 handling ambisonic formats.
In decode (but not encode) terms the QS system was broadly the same as Matrix H and there was, very briefly, a modification for the QSD-2 made available for the UK market that allowed the QSD-2 to decode Matrix H. It was a simple mod that changed a couple of phase shift capacitors, sacrificing the Tape Monitor switch to enable the function. I don't think it worked very well and I imagine they didn't make many, and probably sold even fewer - especially as by the time the unit was available, the BBC were about to move on to Matrix HJ, and Sansui didn't move with them, rendering it all but useless.

 

[fizzywiggs41]

What do you mean by "Matrix H and HJ adapter" fizzy? The QSD-2 didn't handle Ambisonic natively, did you have one that was custom modified, or did you patch an Ambisonic decoder into the QSD somehow? You've got me curious!

Note that both H and HJ were quad systems , and not ambisonic. Ambisonic designated UHJ , came about sometime later in the 70's probably 79 , but that's a good guess.

It should be mentioned that Quad matrix HJ was a compromise of BBC QUAD MATRIX H and the NRDC'S 45J (the early ambisonic system of .).

HJ was compatible with BBC MATRIX H and 45 J.

Not a problem with playback in my quad system utilizing the QT 1, as the adapter was hooked up to my QSD-2.

You should check out those threads (must be 3 or 4 perhaps) located in the" matrix quad legacy" area .( The ones that mention quad matrix BBC MATRIX H and BBC MATRIX HJ).
(there is also a thread on matrix h in the ambisonic section, which does not belong there , but that's up to the moderator to correct )
There are some Integrex decoder pictures relevant to the matrices in practice back then and they utilized H and HJ along with SQ and RM , and should even be some other decoders of note, (eg; Comcor , Sansui, . .....)
Always wanted one of those years ago , but near impossible getting them across the pond.


Lots of very relevant matrix quad info there for anyone still interested in matrix quad .

 

[surround.sound.enthusiast]

Thanks Soundfield and Fizzywiggs41. I don't know too much about the matrix H / HJ, and UHJ formats. I've always mentally lumped them together in the ambisonics pile because of the progression from H to HJ to UHJ (correct me if I'm wrong there again). I've read some of the articles on them, but I haven't come across much of any of the three formats in the United States as they were no where near as prevalent as in the U.K. So, it's a matter of pick them up when I find them, but I don't yet have the equipment to play any of them back properly.

So Fizzy, where you just using a regular QSD-2 for matrix H / HJ playback, or a special version like Soundfield mentioned (which is more news to me)?

 

[MidiMagic]

In the BBC quad trials articles, they gave a simple expedient of using psi phase shifts to make one stereo channel lead and the other lag, and then feed the resulting RM signal into the Sansui variomatrix. I don't have the articles handy right now, and can't remember which channel leads.

90 degrees total (45 lead and 45 lag, or 90 lead and 0 lag) gave BMX
45 degrees total gave H
22.5 degrees total gave HJ
12 degrees total gave UHJ

All "great circle" (on the Poincare sphere) matrices can be converted from one to another by applying sum-and difference and/or psi phase shifting.

 

[fizzywiggs41]

Thanks Soundfield and Fizzywiggs41. I don't know too much about the matrix H / HJ, and UHJ formats. I've always mentally lumped them together in the ambisonics pile because of the progression from H to HJ to UHJ (correct me if I'm wrong there again). I've read some of the articles on them, but I haven't come across much of any of the three formats in the United States as they were no where near as prevalent as in the U.K. So, it's a matter of pick them up when I find them, but I don't yet have the equipment to play any of them back properly.

So Fizzy, where you just using a regular QSD-2 for matrix H / HJ playback, or a special version like Soundfield mentioned (which is more news to me)?

MATRIX H and HJ were not broadcast in the USA as it was soley a product of the UK. The BBC later the Independent Broadcasting Association used HJ and later UHJ.
But the BBC utilized Matrix H as it was their child .
Only 2 albums I know of utilized H . Norrie Paramor-40 years of TV a BBC record from 76 which is not indicated as matrix H quad and one on the Virgin label....David Bedford - Instructions For Angels from 77.
There was also believed to be one or two on the Philips label. That would be no surprise as The Netherlands Dutch radio (NOS) was an early advocate of BBC Matrices. And I do believe some other Norwegian countries as well.

To reiterate BBC MATRIX H and MATRIX HJ are QUAD Matrices , and UHJ was known as a Kernel system of multichannel .

Yes I used my Sansui QSD -2 and it had a little box adapter attached after the decoder which had a Matrix H and HJ switch.

 

[surround.sound.enthusiast]

Thanks fizzywiggs!

 

[fizzywiggs41]

In the BBC quad trials articles, they gave a simple expedient of using psi phase shifts to make one stereo channel lead and the other lag, and then feed the resulting RM signal into the Sansui variomatrix. I don't have the articles handy right now, and can't remember which channel leads.

90 degrees total (45 lead and 45 lag, or 90 lead and 0 lag) gave BMX
45 degrees total gave H
22.5 degrees total gave HJ
12 degrees total gave UHJ

All "great circle" (on the Poincare sphere) matrices can be converted from one to another by applying sum-and difference and/or psi phase shifting.

From what I've read , a 60 degree phase shift of the right channel with an adaptor with any RM decoder provides the best listening of H in quad.
However the "encode " is actually 47.5 degrees with an RM encoder.

Also I believe my adaptor preceded my Sansui QSD-2.

Should be tried out with an SM Decoder in the "involve " mode for anyone with that device.

 

[quadaholic]

Dear Midi Magic,

I "dabbled" with decoding H a few years ago, and while I was initially lured in by the idea of H being not too far removed from QS, once I started digging into the tech. info, it started seeming less and less so. I wonder if a lot of these recommendations were a result of that particular point in time, where expectations of channel separation were a lot lower. In any case, I ultimately found (at least for me) that H is its own beast (emphasis on "beast") with more annoying phase angles to deal with, and a lot more redundant audio to eliminate than QS. Having said all that, definitely give any workarounds a shot and see how it goes. Being able to hear something is definitely better than nothing when it comes to good music.

 

[surround.sound.enthusiast]

Coming back around to this part of the discussion:

...a modification for the QSD-2 made available for the UK market that allowed the QSD-2 to decode Matrix H. It was a simple mod that changed a couple of phase shift capacitors, sacrificing the Tape Monitor switch to enable the function. I don't think it worked very well and I imagine they didn't make many, and probably sold even fewer - especially as by the time the unit was available, the BBC were about to move on to Matrix HJ, and Sansui didn't move with them, rendering it all but useless.

Take a look at what's on Ebay right now: Sansui QSD-1 w/ Matrix H function



THAT, truly is a rarity. The seller is in Northampton, U.K. - anybody know if it might be a fellow QQ'er?

 

[DuncanS]

Coming back around to this part of the discussion:


Take a look at what's on Ebay right now: Sansui QSD-1 w/ Matrix H function

View attachment 48397

THAT, truly is a rarity. The seller is in Northampton, U.K. - anybody know if it might be a fellow QQ'er?

…. and expensive! £995/US$1233!

 

[fizzywiggs41]

Coming back around to this part of the discussion:


Take a look at what's on Ebay right now: Sansui QSD-1 w/ Matrix H function

View attachment 48397

THAT, truly is a rarity. The seller is in Northampton, U.K. - anybody know if it might be a fellow QQ'er?

Wow, I mean wow it's got a Matrix H adapter. That's a new one for me. Although Sansui did sell decoders in the UK with H , but in late 77 or early 78 IIRC.

The price is not worth it , as you can get an Involve decoder and make an adapter with the 48 degree shift ....or not at all as some people on this site state that The Involve decoder does H and HJ decoding quite well.

 

[fizzywiggs41]

…. and expensive! £995/US$1233!

Way too much , right Duncan?

 

[DuncanS]

Way too much , right Duncan?

Yep. Especially when compared to a Surround Master!

 

[fizzywiggs41]

I received the following reply from the BBC today regarding the Alan Freeman Matrix H broadcast on January 28th 1978:

The session material used in the programme was as follows:
The Rods (repeat of 12/11/77 – “Life on the Line”)
Queen (repeat of 03/12/77 – “It’s Late” and 10/12/77 – “Melancholy Blues”)
John Martyn – “Small Hours”
Graham Parker and the Rumour – “Watch the Moon Come Down”
Rezillos – “Top of the Pops”
Siouxsie and the Banshees – “Love in a Voi

Tracks by the following artists were also played:
The Edgar Winter Group (“Frankenstein”/“Bull Fight and Toreador’s Song” - part of theme tune with “At the Sign of the Swinging Symbol”? It’s played at beginning and end, and is only a few seconds each time)
Manfred Mann’s Earth Band
Bob Dylan
XTC
Bill Bruford
Starcastle
Rush
David Sancious
Santana
Pink Floyd
George Harrison
Hot Snax
Jimi Hendrix
Hank C. Burnette
Roxy Music

I hope this helps,

Kind regards

I must wholeheartedly agree with @Old Quad Guy .....

That would have been a way cool Matrix H broadcast to catch !!!

Thanks for this info btw ...@tadploe

 

[kfbkfb]

Some posts in this thread have mentioned using a modified Sansui QS decoder to decode matrix H, in some cases these are QS variomatirx decoders - I was wondering if anyone has listened to matrix H encoded content with a basic, no logic decoder and the same H encoded content with a "variomatrix" logic assisted decoder - does matrix H benefit a lot from using a logic assisted decoder?


Kirk Bayne