SQ Shadow Vector Soundfield Mapping

[Owen Smith]

So how goes the testing? This thread has been quiet for many months.

 

[malcolmlear]

The CBS Labs 4212 SQ position encoder has 24 specific locations (including LF,CF,RF,RB,CB,LB) and provides optimum SQ encoding for each of these 24 locations.

Are there any plans to design a logic directed SQ decoder that will decode to each these 24 positions (depending on which of the 24 positions is loudest at any given moment) rather than the current 6 locations the Shadow Vector decodes?

4212 front panel:
https://www.worldradiohistory.com/Archive-All-Audio/Archive-Audio/70s/Audio-1973-07.pdf#page=24

Kirk Bayne

The Shadow Vector actualy has an infinite number of decode locations. The decoder moves its decode location dynamically to the primary sound source on the Scheiber Sphere, the source is then mixed and directed with precision to the 4 channel output channels. This is process replicated at every octave (9 bands).

 

[malcolmlear]

So how goes the testing? This thread has been quiet for many months.

All is good, code is now optimised so a cooling fan is now not necessary. I have 3 preproduction units that have been running almost continuously for 24 months without missing a sample (the CPU code is instrumented and the FPGA performs checks as well). Now awaiting a reply from Fredblue as to whether he able to do a review.

 

[malcolmlear]

If it's the first logic directed Matrix H decoder specifically designed for Matrix H, I think it should decode both Matrix H formats.


Kirk Bayne

The 'H' decodes H76, and 'BHJ' decodes H79 which was when it merged with UHJ.

 

[steelydave]

All is good, code is now optimised so a cooling fan is now not necessary. I have 3 preproduction units that have been running almost continuously for 24 months without missing a sample (the CPU code is instrumented and the FPGA performs checks as well). Now awaiting a reply from Fredblue as to whether he able to do a review.

I hope he says yes because in my estimation there's no one here more qualified both in terms of knowing what a good decode should sound like and also the number of matrix quad LPs he's heard decoded than my main man @fredblue !

 

[malcolmlear]

If the decider isn’t an ambisonic one then it probably won’t *properly* extract a third, or any, channel. The effect might be interesting but incorrect. Ambisonics encodes direction, not loudspeaker feeds. In UHJ, specifically 2 channel BHJ, the fully extracted channels are W (omni pressure), X (front to back velocity) and Y (left to right velocity), from which the B-format decoder generates signals for the 4 or more horizontally placed ‘speakers. So the question is, why not just use a proper UHJ decoder (Eg. Bruce Wiggins Wigware or one of the used Meridian boxes)?

For anyone wanting to get into the maths, just do a search, “is my decoder ambisonic?”, and you will get a load of academic papers with plenty of detail.

It decodes the 2 channel BHJ accuratly, as per published data and that should include all sound channels. Like all 2 channel matrix systems BHJ can be described using the Scheiber Sphere which theorically includes n number of decode channels. Decoding 4 channels equally spaced around the sphere would decode all sound sources with correct location (providing encoding was done correctly).

 

[BJMarsh]

I'm pumped up on this. Good work, Malcolm. This is very exciting. Now the inevitable questions: when & how much?

 

[malcolmlear]

I'm working on updated spreadsheets this week and release price at the end of this process. I can say it will cost more than the Surround Master V3 due to both a high performance CPU and FPGA, but not by much. It will also be shipped with a USB to optical adapter for playback from USB sources. A nice little bonus feature is the option of adding silent metadata headers to digital audio files that will override the front panel controls, thus ideal decoding settings for various source material can be automated. Software to add the metadata will be supplied with the unit.

 

[Owen Smith]

My problem continues to be my amp has no analogue multi channel inputs. I've been looking out for analogue to HDMI solutions but the only one I found handled stereo only. I contacted the seller (looked like a small company) and he was completely uninterested in designing a multi channel version. He even said something along the lines of "Why would anyone need one of those? Multi channel audio is over HDMI already" or words to that effect. I sent an explanation of why but never got a reply.

 

[J. PUPSTER]

My problem continues to be my amp has no analogue multi channel inputs. I've been looking out for analogue to HDMI solutions but the only one I found handled stereo only. I contacted the seller (looked like a small company) and he was completely uninterested in designing a multi channel version. He even said something along the lines of "Why would anyone need one of those? Multi channel audio is over HDMI already" or words to that effect. I sent an explanation of why but never got a reply.

Heathens!

After my "repaired" QRX-8001 went down with multiple problems, I ended up with an Emotiva UMC-200 Preamp (has both HDMI and 7.1 analog outputs) and Emotiva BasX A7 amp to handle my Quad material+.

I'm working on updated spreadsheets this week and release price at the end of this process. I can say it will cost more than the Surround Master V3 due to both a high performance CPU and FPGA, but not by much. It will also be shipped with a USB to optical adapter for playback from USB sources. A nice little bonus feature is the option of adding silent metadata headers to digital audio files that will override the front panel controls, thus ideal decoding settings for various source material can be automated. Software to add the metadata will be supplied with the unit.

Looking forward to it Malcolm and the added metadata control files is really innovative!

 

[proufo]

I'm working on updated spreadsheets this week and release price at the end of this process. I can say it will cost more than the Surround Master V3 due to both a high performance CPU and FPGA, but not by much. It will also be shipped with a USB to optical adapter for playback from USB sources. A nice little bonus feature is the option of adding silent metadata headers to digital audio files that will override the front panel controls, thus ideal decoding settings for various source material can be automated. Software to add the metadata will be supplied with the unit.

Maybe this has been discussed. Please Malcom make the firmware upgradeable, No matter how sure one is of the definiveness of something, there is always room for improvement.

 

[Owen Smith]

Maybe this has been discussed. Please Malcom make the firmware upgradeable, No matter how sure one is of the definiveness of something, there is always room for improvement.

I asked that question some time back on this thread. If I remember correctly the firmware is on some removable media inside the device so can be upgraded by swapping that.

 

[mandrix]

My problem continues to be my amp has no analogue multi channel inputs. I've been looking out for analogue to HDMI solutions but the only one I found handled stereo only. I contacted the seller (looked like a small company) and he was completely uninterested in designing a multi channel version. He even said something along the lines of "Why would anyone need one of those? Multi channel audio is over HDMI already" or words to that effect. I sent an explanation of why but never got a reply.

Yes it's unfortunate. I have a decent HDMI > 5.1 box from Monoprice. But going the other direction is problematic to find.

 

[BJMarsh]

Yes it's unfortunate. I have a decent HDMI > 5.1 box from Monoprice. But going the other direction is problematic to find.

Is there such a beast?

 

[mandrix]

Is there such a beast?

Yes indeed. I bought mine off the Amazon a few years ago, but should be listed on the Monoprice site, or at least they were at one time.
I no longer use it, but it worked perfectly fine jacked into the inputs of an analog input AVR. You will have to buy converter cables for 3.5mm > RCA as the device only has the 3 stereo 3.5mm outs. (5.1). It also has an HDMI passthrough port.

 

[Sonik Wiz]

Yes indeed. I bought mine off the Amazon a few years ago, but should be listed on the Monoprice site, or at least they were at one time.
I no longer use it, but it worked perfectly fine jacked into the inputs of an analog input AVR. You will have to buy converter cables for 3.5mm > RCA as the device only has the 3 stereo 3.5mm outs. (5.1). It also has an HDMI passthrough port.

I belive @BJMarsh was referring to 5.1 analog out to HDMI to connect to an HDMI input only receiver etc.

 

[BJMarsh]

I belive @BJMarsh was referring to 5.1 analog out to HDMI to connect to an HDMI input only receiver etc.

Correct, I need 5.1 to HDMI.

 

[malcolmlear]

I asked that question some time back on this thread. If I remember correctly the firmware is on some removable media inside the device so can be upgraded by swapping that.

Firmware is indeed on a SD card and is upgradable.

 

[mandrix]

Correct, I need 5.1 to HDMI.

Apologies. I had already said it was problematic so just assumed you were asking about the opposite. If that makes any sense. lol

 

[kfbkfb]

(the only description I can think of for this issue):

Given: sound_A in sequential frequency bands:

band 1: sound_A is the loudest sound in this band (logic system makes sound_A more separate from the other sounds in this band)

band 2 (next sequential band up from band 1): sound_A in band 1 is also in band 2, but softer in volume than sound_B in band 2, so the logic system makes sound_B more separate, is this logic action audible [sound_A precisely located in band 1 but less precisely located in band 2]?


Kirk Bayne