New Surround Master coming! Its a jump to the left and a step to the right

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proufo

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Dear all

I have been doing some background investigation on the new SM V2 and I will be advising all of some findings shortly but as a general operational note, it is better to operate the thing with the main input level knob as fully advanced clockwise as possible to just below the onset of the clipping light. If you are dumb like me you will be setting the thing with all knobs at 12 o clock by habit - not right. Doing the fully clockwise thing will optimise the decode operation, distortion and signal to noise ratio.

Regards

Chucky
Would you explain how the lamp circuitry works?

Is it derived from a signal in the ADC that informs of overload, or is it an analog level-calibration performed in the factory?

Thanks in advance.
 
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J. PUPSTER

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.... It’s like getting the torque right on bolts – tighten them up till they shear then back off a quarter of a turn!
Fortunately, it’s not that permanent. You guys should have told me; I’ve been running mine at only about 2 o’clock. Shoot, now I’ll have to go back and listen to all that great music all over again, but this time only better😉
 

ar surround

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Dear all

I have been doing some background investigation on the new SM V2 and I will be advising all of some findings shortly but as a general operational note, it is better to operate the thing with the main input level knob as fully advanced clockwise as possible to just below the onset of the clipping light. If you are dumb like me you will be setting the thing with all knobs at 12 o clock by habit - not right. Doing the fully clockwise thing will optimise the decode operation, distortion and signal to noise ratio.

Regards

Chucky
I can see how it would optimize the distortion and SNR, but how does the main input level knob position affect the decode operation?
 

J. PUPSTER

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I can see how it would optimize the distortion and SNR, but how does the main input level knob position affect the decode operation?
Chucky- "will be advising all of some findings shortly" and chortle (laugh in a breathy, gleeful way; chuckle); so we'll just have to wait and see; and will it be for all modes?
 

M-D-Z

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I am guessing that this is the best way to peak level-match this component to all other clip-points throughout the system.

This adjustment then optimizes for ideal "gain structure" and provides the greatest window through which the cleanest, most dynamic musical content can pass and/or be processed, uncluttered of accumulated noise floor throughout the signal chain?
 

DuncanS

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Dear all

I have been doing some background investigation on the new SM V2 and I will be advising all of some findings shortly but as a general operational note, it is better to operate the thing with the main input level knob as fully advanced clockwise as possible to just below the onset of the clipping light. If you are dumb like me you will be setting the thing with all knobs at 12 o clock by habit - not right. Doing the fully clockwise thing will optimise the decode operation, distortion and signal to noise ratio.

Regards

Chucky
I didn't read the manual :whistle: but that's what I have been doing anyway :smokin as it sounded better to these knackered old ears!
 

Mark Anderson

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Dear all
it is better to operate the thing with the main input level knob as fully advanced clockwise as possible to just below the onset of the clipping light.
Great tip as I have multiple volume controls in the chain and have been playing with adjustments to all three. To feed the matrix decoders I use the zone 3 output from the Marantz SR-7010 to a 4 channel distribution amp and then into each decoder
1569457724876.png


I have found that a unity gain approach works best with the distribution amp around 8 to 9 and the SM2 to 9. The zone volume at 8.
When all the volumes were set lower and the zone output higher a lot of openness was lost.
 

quadsearcher

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I've been using the SM1 with a preamp that has a volume control, using the variable line level outputs (meant for driving a power amp). I found there is a sweet spot for the level that drives the decoder, although I kind of didn't dare turn it full CW. The preamp is a unit with IIRC a 2.5v max output (depending on input). I have the volume control set around 2 o'clock.
 

chucky3042

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Would you explain how the lamp circuitry works?

Is it derived from a signal in the ADC that informs of overload, or is it an analog level-calibration performed in the factory?

Thanks in advance.
Its analogue circuitry that is buffered and set to clip just before the opamps get into saturation (soft clip )
 

chucky3042

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Actually it does not effect the decode much as it is completely linear, more in optomising the dynamic range it facilitates even more linear control even at the really low signal levels......minor stuff
 

chucky3042

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I can see how it would optimize the distortion and SNR, but how does the main input level knob position affect the decode operation?
Actually it does not effect the decode much as it is completely linear, more in optomising the dynamic range it facilitates even more linear control even at the really low signal levels......minor stuff
 

Scott65

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I seem to be back to about 2 o'clock with most things tonight, as closer to 3 and it starts to clip, so I guess I was about right after all.
Where do others here land at just before you get a little red blinky?
Since today I have been having it just before 2 o'clock position - prior to today 12 o'clock. Seems to be going well so far.
 
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