A Matrix Decoder curiosity item on Japanese Auction site

QuadraphonicQuad

Help Support QuadraphonicQuad:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Somewhere in my digging in the past few months, I think I remember a quick blurb on the QM-4 format. I wanted to say it was yet another variant of Regular Matrix in Japan,
but of course I can't put my fingers on that right now. It's curious how QM-4 is it's own setting and not included as a sub-function under "matrix" (along with SQ and RM). It
might just be an ambient extractor along the lines of a Hafler circuit.

I did a bit of searching but couldn’t find much detail on QM-4. There were two Japanese industry standards for matrix systems. RM covered “surround oriented” matrix systems (e.g. QS) QM covered “front-oriented” matrix systems (e.g. QM4, Stereo-4 and QX).

The fundamental difference between RM and QM was in the separation between the channels. RM has equal separation adjacent channels, QM has greater separation between front channels but lower separation between front and back channels.

(QX, a Denon invention, was slightly different in that it required a unique five speaker layout).
I don't think either QM-4 or QX were adopted outside of Japan.
 
I did a bit of searching but couldn’t find much detail on QM-4. There were two Japanese industry standards for matrix systems. RM covered “surround oriented” matrix systems (e.g. QS) QM covered “front-oriented” matrix systems (e.g. QM4, Stereo-4 and QX).

The fundamental difference between RM and QM was in the separation between the channels. RM has equal separation adjacent channels, QM has greater separation between front channels but lower separation between front and back channels.

(QX, a Denon invention, was slightly different in that it required a unique five speaker layout).
I don't think either QM-4 or QX were adopted outside of Japan.

Good research. Explanation sounds right regarding RM/QS/QM. And I've never even heard of QX!
Many quad receivers sold in the US we're basically SQ with RM thrown in as a token concession to playing QS. I imagine this is due to not wanting to adhere to Sansui decoding standards & therefore pay a license fee. In Japan they just had SQ & the home grown QM/QX to go along with SQ.

And soes anyone know where I can get control knobs with the LED pointer built in similar the ones in the photos?
 
Good research. Explanation sounds right regarding RM/QS/QM. And I've never even heard of QX!
Many quad receivers sold in the US we're basically SQ with RM thrown in as a token concession to playing QS. I imagine this is due to not wanting to adhere to Sansui decoding standards & therefore pay a license fee. In Japan they just had SQ & the home grown QM/QX to go along with SQ.

And soes anyone know where I can get control knobs with the LED pointer built in similar the ones in the photos?
Didn't see any LEDs, but I have come across these before with LED illumination at the bottom of control knobs Illuminated Controls
same company show some custom knobs
40105
scroll down link
 
I did a bit of searching but couldn’t find much detail on QM-4. There were two Japanese industry standards for matrix systems. RM covered “surround oriented” matrix systems (e.g. QS) QM covered “front-oriented” matrix systems (e.g. QM4, Stereo-4 and QX).

The fundamental difference between RM and QM was in the separation between the channels. RM has equal separation adjacent channels, QM has greater separation between front channels but lower separation between front and back channels.

(QX, a Denon invention, was slightly different in that it required a unique five speaker layout).
I don't think either QM-4 or QX were adopted outside of Japan.

Hi. Soundfield

Good researching there, you have come to the same results that I have looking into these QM-QX Matrix systems there would be technical papers on these matrix systems but being only Japanese in house and only sold in Japan there would be no English documents available to explain in detail.
BBQ.....
 
I did a bit of searching but couldn’t find much detail on QM-4. There were two Japanese industry standards for matrix systems. RM covered “surround oriented” matrix systems (e.g. QS) QM covered “front-oriented” matrix systems (e.g. QM4, Stereo-4 and QX).

The fundamental difference between RM and QM was in the separation between the channels. RM has equal separation adjacent channels, QM has greater separation between front channels but lower separation between front and back channels.

(QX, a Denon invention, was slightly different in that it required a unique five speaker layout).
I don't think either QM-4 or QX were adopted outside of Japan.

I came across this Diatone ◆ 4-channel receiver DA-Y56 4ch...….. have a look at the switch position of SQ/QM???????????

40235
40236
40237
40238
 
I came across this Diatone ◆ 4-channel receiver DA-Y56 4ch...….. have a look at the switch position of SQ/QM???????????

View attachment 40238

That's pretty weird!
Although I suspect this was a rather budget receiver trying to be all things to all men and the differences between the matrix decoding modes was minimal. The QM decoder was probably little more that a Hafler type circuit and so yes you could have stuck SQ material through it - wouldn't have done very much good though!
 
I came across this Diatone ◆ 4-channel receiver DA-Y56 4ch...….. have a look at the switch position of SQ/QM???????????

View attachment 40235View attachment 40236View attachment 40237View attachment 40238
How do you find this stuff?
SQ/QM is weried and so is a plugged hole for remote balancer. As mentioned before some consumer electronics like this was intended for only the Japanese market. Why wouil everything be in English on the front panel? Did Kenwood/Sansui/Pioneer etc do it this way even for Asian destined sales?
 
The more i look these Diatones, the more it seems JVC... did Mitsubishi have a connetion with JVC? In theory no, but...
 
How do you find this stuff?
SQ/QM is weried and so is a plugged hole for remote balancer. As mentioned before some consumer electronics like this was intended for only the Japanese market. Why wouil everything be in English on the front panel? Did Kenwood/Sansui/Pioneer etc do it this way even for Asian destined sales?

Yeah, that receiver is another unique critter, and there are plenty of them from the Japanese market. That plugged balancing port is the that first I've ever seen. For every piece of Japanese quadraphonic hardware that I've ever looked at pictures of, they seem to have gone with English labeling on the front panels. The back panels are usually a mix, the RCA connections are labeled in English, but anything else may be in Japanese. This may have been to keep them attractive to potential non-Japanese markets, or could even be a hold-over from post WW2 industrialization, just like 50Hz and 60Hz electricity both being utilized in Japan.
 
Both Technics and JVC/Victor offered DIN Style plugs with wired balancers on the front of many receivers, preamps and integrated amps. There was one for early Sansui receivers as well and is uncommon and extremely pricey. I have the Technics and Victor balancers and without service thay make a lot of unwanted noise.
 
That is a weird selector alright.

QM was the matrix adopted early on by Toshiba, fwiw.
Toshiba later dropped QM for RM, using QS encoders. There had also been claims that they used Sansui encoders for the QM material, too. I have some "Pro Use" records from Toshiba that feature the QS logo on the inner info sheet. Gotta say, they're some of the best sounding quad records I've heard.
 
Toshiba later dropped QM for RM, using QS encoders. There had also been claims that they used Sansui encoders for the QM material, too. I have some "Pro Use" records from Toshiba that feature the QS logo on the inner info sheet. Gotta say, they're some of the best sounding quad records I've heard.
Yeah, those Toshiba “Pro Use” titles really decode well through a Surround Master, too bad they didn’t produce more CDs using that.
 
Toshiba released an SQ sampler in Germany with Bellaphon with some pictures of Toshiba quad gear:
https://www.discogs.com/Various-The-Fantastic-World-Of-Quadro/release/5637276Here is from the user manual of the Toshiba SA-504 shown on the sampler:
20201017_124259.jpg

Diatone must have got confused over the formats somehow, as Toshiba states QM should played in R-MTX in this manual. Can't seem to find a manual for the Diatone receiver.
 
Toshiba released an SQ sampler in Germany with Bellaphon with some pictures of Toshiba quad gear:
https://www.discogs.com/Various-The-Fantastic-World-Of-Quadro/release/5637276Here is from the user manual of the Toshiba SA-504 shown on the sampler:
View attachment 58111
Diatone must have got confused over the formats somehow, as Toshiba states QM should played in R-MTX in this manual. Can't seem to find a manual for the Diatone receiver.
RM would be the correct setting for QM. I've tried both QS and SQ settings to play a QM record, and the effect was noticeably better in QS.
 
Toshiba later dropped QM for RM, using QS encoders. There had also been claims that they used Sansui encoders for the QM material, too. I have some "Pro Use" records from Toshiba that feature the QS logo on the inner info sheet. Gotta say, they're some of the best sounding quad records I've heard.


Yes I know, and thanks.

What's weird is that they had QM and SQ as the same selection . I always thought QM was one of those more associated with the Regular Matrix family.
Maybe as @Soundfield suggested it was a basic matrix like a Dynaquad .
 
A little more on this:

The Japan Phonograph Record Association (JPRA) and the Electronic Industry Association of Japan (EIAJ) standards for matrix recordings:

- RM - Regular Matrix - Equal-separation basic matrix
- QM - Quadraphonic Matrix - Forward-oriented basic matrix (e.g. EV)
- PM - Phase Matrix - All SQ-related matrix systems
- CD-4 - Compatible Discrete - CD-4
- UX - Uniform Matrix - All UMX-related matrix systems

QX and XM are not standards of either JPRA or EIAJ. They were trademarks of Denon.

QM-4 would be a brand and is different from the QM standard.
 
Back
Top