ALL TESTS ON THE SURROUND MASTER

QuadraphonicQuad

Help Support QuadraphonicQuad:

gene_stl

900 Club - QQ All-Star
QQ Supporter
Joined
Nov 3, 2019
Messages
941
Location
St.Louis
I mean end user programmable.


 

chucky3042

2K Club - QQ Super Nova
Joined
Apr 9, 2012
Messages
2,465
I mean end user programmable.


Nup, maybe it will be something to explore on the super pre amp. I am open to suggestions.
 

chucky3042

2K Club - QQ Super Nova
Joined
Apr 9, 2012
Messages
2,465
And I want a one of those amps too. It will reduce my footprint of gear considerably....and time to try a 40 year younger amp(s).
Yep, i will be ditching my big lumpy stuff also
 

barfle

500 Club - QQ All-Star
Joined
Oct 28, 2005
Messages
508
Location
Meridian, ID
Hey, @chucky3042 I've been looking seriously at the SM3, and have a question. I looked at your website and even downloaded the manual, and this topic isn't covered, as far as I can see (although I've overlooked the obvious many times before).

There's an optical input on the SM, along with stereo copper inputs. I see that I have an optical output from my Oppo 105, which would be useful in decoding the handful of (supposedly) quad matrixed CDs I have, so that's neat. But what I don't see is how to select between the copper and optical inputs.
 

Sonik Wiz

👂 500 MPH EARS 👂
QQ Supporter
Joined
May 30, 2005
Messages
3,608
Location
Kansas City
Hey, @chucky3042 I've been looking seriously at the SM3, and have a question. I looked at your website and even downloaded the manual, and this topic isn't covered, as far as I can see (although I've overlooked the obvious many times before).

There's an optical input on the SM, along with stereo copper inputs. I see that I have an optical output from my Oppo 105, which would be useful in decoding the handful of (supposedly) quad matrixed CDs I have, so that's neat. But what I don't see is how to select between the copper and optical inputs.
Me thinks this was addressed somewhere in the official SM v3 thread. Someone said they had wonky conflicts when both analog & digital were utilized. IIRC Chuckys response was that it never occurred to Involve that both would be used simultaneously. So the way you choose between input sources is done by cable hook up.

I might point out that if using digital the signal is immediately converted to analog inside the box. So it would need to be considered if you think the D/A conversion is superior in your Oppo 105 or the Involve unit.

I still don't have a precise understanding of this but Chucky has said all the "math" is done in digital but what you listen to stays analog. So it seems the SM units are an interesting hybrid of both.
 

chucky3042

2K Club - QQ Super Nova
Joined
Apr 9, 2012
Messages
2,465
Hey, @chucky3042 I've been looking seriously at the SM3, and have a question. I looked at your website and even downloaded the manual, and this topic isn't covered, as far as I can see (although I've overlooked the obvious many times before).

There's an optical input on the SM, along with stereo copper inputs. I see that I have an optical output from my Oppo 105, which would be useful in decoding the handful of (supposedly) quad matrixed CDs I have, so that's neat. But what I don't see is how to select between the copper and optical inputs.
Hi Barfle

Sonik is correct. Basically the output of the optical stuff and the RCA stuff go into a MIXER. The logic is that if there is no signal on one then you just get the other output.....1+0 = 1. We saved another input selector knob in doing so. Oh yes the SM is a digital/ analogue hybrid to some extent but all the signal processing including the variomatrix is done in the DSP with the exception of the Hilbert transform (90 degree phase shift network) was done in a 5 stage analogue opamp network.
 

Sonik Wiz

👂 500 MPH EARS 👂
QQ Supporter
Joined
May 30, 2005
Messages
3,608
Location
Kansas City
Oh yes the SM is a digital/ analogue hybrid to some extent but all the signal processing including the variomatrix is done in the DSP with the exception of the Hilbert transform (90 degree phase shift network) was done in a 5 stage analogue opamp network.

Thanks for the clarification. While you're mentioning phase shifts I have another long standing question about design. In the Sansui units various combos of L,R,L+R,L-R were used for decoding & enhancement. Phase shifts of 90 deg were applied after decoding right at the outputs to correct for the phase shifts in encoding. Is this how you do it?
 

chucky3042

2K Club - QQ Super Nova
Joined
Apr 9, 2012
Messages
2,465
Thanks for the clarification. While you're mentioning phase shifts I have another long standing question about design. In the Sansui units various combos of L,R,L+R,L-R were used for decoding & enhancement. Phase shifts of 90 deg were applied after decoding right at the outputs to correct for the phase shifts in encoding. Is this how you do it?
Hi Sonik

In fact we do the phase shifts right after the input buffer and all the L/ L90/R/R90 signals are input to the DSP for final computations.
 

kfbkfb

1K Club - QQ Shooting Star
QQ Supporter
Since 2002/2003
Joined
Feb 20, 2003
Messages
1,467
Location
Midwest USA
Any reasonable possibility of doing the 90 degree phase shifts in the SM digitally (avoiding analog component tolerance and aging errors)?


Kirk Bayne
 

chucky3042

2K Club - QQ Super Nova
Joined
Apr 9, 2012
Messages
2,465
Any reasonable possibility of doing the 90 degree phase shifts in the SM digitally (avoiding analog component tolerance and aging errors)?


Kirk Bayne
Its done outside the DSP. The analogue components are accurate on the frequency shifts
 

barfle

500 Club - QQ All-Star
Joined
Oct 28, 2005
Messages
508
Location
Meridian, ID
Me thinks this was addressed somewhere in the official SM v3 thread. Someone said they had wonky conflicts when both analog & digital were utilized. IIRC Chuckys response was that it never occurred to Involve that both would be used simultaneously. So the way you choose between input sources is done by cable hook up.

I might point out that if using digital the signal is immediately converted to analog inside the box. So it would need to be considered if you think the D/A conversion is superior in your Oppo 105 or the Involve unit.

I still don't have a precise understanding of this but Chucky has said all the "math" is done in digital but what you listen to stays analog. So it seems the SM units are an interesting hybrid of both.
As I envision my potential setup, I would have an analog preamp from my turntable connnected (fairly) permanently to the analog inputs to decode my vinyl sources and an optical connection from my blu-ray to decode any matrix encoded CDs. Naturally, I wouldn’t do both at once.
 

barfle

500 Club - QQ All-Star
Joined
Oct 28, 2005
Messages
508
Location
Meridian, ID
Hi Barfle

Sonik is correct. Basically the output of the optical stuff and the RCA stuff go into a MIXER. The logic is that if there is no signal on one then you just get the other output.....1+0 = 1. We saved another input selector knob in doing so. Oh yes the SM is a digital/ analogue hybrid to some extent but all the signal processing including the variomatrix is done in the DSP with the exception of the Hilbert transform (90 degree phase shift network) was done in a 5 stage analogue opamp network.
While I suspected that to be the case, I also thought that having a selector of some sort (automagic if there was light on the optical input?) would reduce the likelihood of noise from the unused input. Naturally, I wasn’t involved (sorry) in the design and test, so I don’t know if that was ever an issue, but my history in the field makes me look for such things. 🙄
 

MidiMagic

1K Club - QQ Shooting Star
Joined
Jul 5, 2010
Messages
1,544
Thanks for the clarification. While you're mentioning phase shifts I have another long standing question about design. In the Sansui units various combos of L,R,L+R,L-R were used for decoding & enhancement. Phase shifts of 90 deg were applied after decoding right at the outputs to correct for the phase shifts in encoding. Is this how you do it?
The phase shifting has to be done first. Otherwise the decoder would have the same troubles the Scheiber decoder had with center back material.
 

Sonik Wiz

👂 500 MPH EARS 👂
QQ Supporter
Joined
May 30, 2005
Messages
3,608
Location
Kansas City
0
The phase shifting has to be done first. Otherwise the decoder would have the same troubles the Scheiber decoder had with center back material.
If you are referring to QS encoding, of course you are are correct. I was referring to decoding. It is well documented & well known that Sansui applied 90 deg phase shifts after the decoding by Vario-Matrix.
 
Last edited:
Top