A+ 3.2.5 Best Preference settings

[Jamesroy]

I have A Stellar DAC with built in Preamp, what would the best Preference settings for latest A+ 3.2.5

[buonassi]

What in particular?  There are lot's of settings under preferences.  

[Jamesroy]

I guess that was a crazy question since we all have different equipment. I'm awaits a used MicroRendu with a LPS-1 power supply so I hope it's easy to setup. Not using Roon just may MacBook with an external HD.

[sockpit]

I’d like some advice on upsampling in A+, if there is collective wisdom about this.

 

 

[Jamesroy]

So would I.

[buonassi]

oh boy, where to begin....  

 

as far as settings for a network streamer, I'm not knowledgeable enough to answer.  But I have heard that you can only use 'direct' mode with direct connection to a DAC via usb.  Still, many people are using A+ with the rendu, so it can be done and sounds great from what I read.

 

In short, the whole point of upsampling is to:

 

1. change the aliasing filter to your liking - if you don't like the one on your DAC - IE, you want minimum or intermediate phase, but your DAC doesn't have selectable filters and is linear phase.

 

2. bypass the oversampling done by your DAC - the theory goes like this:  if I can upsample (interpolate) using the power of my computer and send that signal to the DAC, it will be "better" than if I send a native signal to the DAC and allow its chip to oversample it (do interpolation of the additional samples).  

 

3.  Convert PCM> DSD - if your DAC supports DSD, you can experiment with changing PCM to DSD and observing the sonics.  Personally, I like the effect it gives.  It's hard to explain what's going on here, but most of the time, I like it.  Other times I find myself reverting back to PCM.  

 

I'll try and round up some links to other posts that cover the topics of upsampling and reply back.  

[buonassi]

 

I started with the above link, then moved on to this:

 

 

It's a lot of reading.... the goal of this post I think is to understand that there's a tradeoff - if you have a slow rolloff filter, thus reducing the ringing, you could have a very weak filter that doesn't suppress the aliased artifacts above nyquist.   Conversely, if you have a sharp filter, you end up with more ringing, but great suppression of aliased artifacts.

 

Also, if you want to get crazy about this stuff - spend some time on this guy's blog.  He's active here on CA as well.  

http://archimago.blogspot.com/2016/07/musings-digital-interpolation-filters.html

 

 

Finally, if all you're looking for are some setting to try, give this a go - it works for me (this week at least).  Also, try upsampling by "power of 2" PCM vs the DSD I show in the pic,  if you don't want to tax your mac's processor so much.  I change my mind all the time, it's really a curse having so many options, beware guys

 

 

[Jamesroy]

Thanks so much for your reply. I'll work on it. Haven't received my MacroRendu don't even have my ethernet cable installed to my Music area.

[buonassi]

sure thing.  in the meantime, there's nothing stopping you from playing with upsampling via direct USB connection to your DAC.  As a standard prerequisite, I would suggest you set "exclusive access" and "integer" mode active on the audio system tab. 

 

Another rule of thumb for upsampling (based on consensus in other threads) is to keep the interpolation to "multiples of 2" - but I can't tell a difference if I select this or the "maximum sample rate".  I suspect your processor works less, though. 

 

Personally, I see the benefit in upsampling.  It's nice to have the option to change the phase characteristics of the passband, giving more attack to transients (minimum phase) or smoother sound with great instrument separation (linear phase).   Or you can try and achieve both by using some intermediate phase setting like 33%. 

 

Happy listening! 

[Jamesroy]

Thanks again. In my Stellar DAC I do have 3 filters to choose from I keep it on 1 Low so far but I don't know what to expect once I get my MicroRendu and hooked up thru ethernet as opposed to usb?

[buonassi]

Dude, if I had a PS audio DAC, I probably would just enjoy the hell out of its magic, and avoid upsampling altogether.  They know what they're doing and have designed the filters to sound better than what I imagine you or I can tune by ear with the A+ software.  That said, you can still have fun experimenting! 

 

I'd like to help facilitate some understanding, just so you know what you're getting into.  Forgive me if I'm stating the obvious or if you already know this, but I saw some of your other posts and want to really ensure you understand how these components get hooked up.  your Mac will send a stream through ethernet to the router or switch.  the switch then sends it through ethernet to the rendu.  finally the rendu will send it to your DAC via USB still.  So the "last mile" is still USB.

 

 

[Jamesroy]

Thanks for the reply. Yes I still new at this and I think the MicroRendu is my last upgrade. So I guess when the signal goes to rendu then there will be some settings there for me to also pick  my Mac with the external HD where my music resides.

[buonassi]

getting a+ connected to the rendu, I don't know about this. But I'll reply if I find the answer. 

[Jamesroy]

I'm pretty sure there is no problem with A+

[buonassi]

absolutely not a problem - there are many users with success.  It's officially supported as far as I know.  I'm pretty sure you select the rendu from the audio system, just like you would a DAC.  But research more as I'm not positive on this.    

 

I found this link that may help, but I haven't read it