Nguyen hi, I had a look to see in the user manual what the output of the oppo is at full volume, but it's not stated, hopefully it must be above the standard of 2v. I've been told from a guy who mods them that it is 2.5v.
Your amp says on this main page that it is <1v input sensitivity
http://shop.grantfidelity.com/Shuguang-Classic-S845MK-Tube-Power-Amplifier-pair.html
Yet when I downloaded the manual it says 4v as you say
https://shop.grantfidelity.com/files/s845mk%20manual.pdf
Your impedance matching to and from the Lightspeed is great from the Oppo's 100ohm and into the S845's 100kohm.
My question to you is do you have enough volume when the Lightspeed is almost at full up?
As "GOD" Nelson Pass and I both state:
QUOTE: "Nelson Pass,we’ve got lots of gain in our electronics. More gain than some of us need or want. At least 10 db more.
Think of it this way: If you are running your volume control down around 9 o’clock, you are actually throwing away signal level so that a subsequent gain stage can make it back up.
Routinely DIYers opt to make themselves a “passive preamp” - just an input selector and a volume control.
What could be better? Hardly any noise or distortion added by these simple passive parts. No feedback, no worrying about what type of capacitors – just musical perfection.
And yet there are guys out there who don’t care for the result. “It sucks the life out of the music”, is a commonly heard refrain (really - I’m being serious here!). Maybe they are reacting psychologically to the need to turn the volume control up compared to an active preamp. Nelson Pass"
Cheers George
