The Roon CTO mentioned that TPDF dither is applied when reducing bit depth from 64 bit to 24 bit, so I guess this must be reason I hear some SQ impact when I apply volume leveling on the linn streamer.
Maybe. With the NDX2, the reduction is to 32 bits, maybe that’s less audible. He says:
“We dither for all reductions…it’s the most important for 16bit output. Some people debate the necessity for 24. For 32, it could probably be skipped but it is still more technically correct to do so, so we do.”
He also gives some examples for other possible causes though,
- Psychoacoustics. Any test of a volume control that does not employ precise level-matching is flawed. Quieter statistically sounds worse
- After level matching, you may discover that the amplifier (or another component) does not perform equally well in all volume ranges
I’ve been playing around with it, with no volume adjustment, it seems better.
That seems obvious. Of course setting the master switch to off turns off all DSP. Why wouldn’t it? He says,
In the off position, its behavior is a shortcut for flipping the enable switches on each of the sections in the DSP Engine to “off” if they are not already off. It does nothing extra. When “on” it has no effect at all–just the absence of forcibly turning that other stuff off.
My point here was that people on that thread had an incorrect conception of what the master switch does in the code path, and it made them subjectively hear different things
I know, I’m not saying it can’t, and he doesn’t say either. It could be either due to the 24 target reduction that the Linn has, as opposed to the 32 of the NDX2, where the dither has less effect, or it could be other things, such as it’s really hard to perform precise level matching with and without leveling, or it could be that you are not superhuman and have unconscious biases like every human. (If you were so inclined, you could rule that out with blind testing)
Maybe I am under some psychoacoustic effect? 
Maybe the Linn streamer does something? But definitely no volume adjustment setting (when loudness is unknown) makes some improvement.
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Yes, or maybe the Linn streamer does something as you say, or I am half deaf, or I might not care enough. Could be anything, in reality or just in your head or my head. I thought you might be interested in the math, mostly
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I see that on the new Roon release it says “UPnP Bridge: bridge your existing UPnP device to Roon”. Does that mean an older generation streamer (I have a Uniti2) can be set up as a Roon device now?
I can see this sentence in the new RoPieeeXL release. RoPieee is not Roon but a Roon Bridge installer with some bells and whistles for Raspberry Pi, the XL is for using UPnP instead of Roon. I don’t think this is what you are looking for
That said, the RooUPnP Extension has existed for about a year and I think this is what you want. It requires an RPi as well
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No he added the same UPnP bridge as in RooUPnP to the latest version.
Yes Ropieee now runs the LMS UPnP bridge software. It may or may not work well. I always found it very temperamental but lots of users use it on here. Ropieee isn’t Roon it’s a custom OS for a raspberry pi that runs Roon bridge amongst other renderers if you choose the XL version. Regular version is Roon Bridge only.
Ah OK thanks
I’m not sure I understand any of that, to be honest. I think I’ll stick with what I’m doing. The Uniti2 can stay as uPnP from the Naim app and Qobuz via ATV.
You posted this.
Roon says no such thing.
This is a 3rd party software called Ropieee that runs on a raspberry pi. It comes in 2 forms Ropieee which turns a Raspberry Pi into a Roon endpoint. Or Ropieee XL which turns a Raspberry Pi in to a Roon endpoint, Apple Airplay, UPnP Renderer, Squeezebox Endpoint. It also now adds additional software called UPnP Bridge which was originally a plugin for the Squeezebox system to allow it to use UPnP renderers for it’s software. It bridges UPnP renderers so they can work in Roon. Many users on here use a version of this as its available for Mac, windows and Linux.
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Indeed, it was a little confusing, as it was mentioned in a email summarising the blog page, and could be mistaken for those of us who don’t know about all these side deviations.
Some of us use Roon to simplify streaming, not to complicate it 
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I think I must thank @Suedkiez for the info about the Roon vol levelling, now I like Roon even more after setting “No volume adjustment when loudness is unknown”.
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Wow thanks! I’ve known about Volume Leveling but didn’t know about “No volume adjustment when loudness is unknown”. either so thanks.
What’s volume leveling all about? I haven’t tried it.
Please see these:
Hope that Richard is OK with the external link.
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Thanks, I’ll take a look. Does it impact on sound quality?