Nubie question on Pure Music and upsampling

[DavidFaik]

I'm running a Mac Mini into a Musical Fidelity M1 DAC (first version).  The USB maxes at just 16 bit 48hz.

Question: So why does it sound much better in Pure Music when I turn on oversampling?

I tried using the SPDIF but the DAC also indicates that it is only receiving the native 44KHz. 

Question: Does that mean that the software oversampling only works with USB and not with the SPDIF?

 

I have a more modern Audiolab MDAC (on another system) that I will be testing with this system over the weekend.  Maybe that will be even better.  USB on that is up to 24-bit/96kHz.

 

Both DACs rate 24-bit/192kHz on coax. 

Question: Do wise members of this community think that I should invest in some kind of USB to Coax anti-jitter thing, or save that money and get a better USB DAC?  I'm in general happy with both my DACs but haven't heard new kit in a long while.

 

The remainder of my system is two Musical Fidelity XT-100's bi amplifying a pair of B&W 705s.  I think that tweaking my source (mac-mini / DAC etc) should be able to reap big sonic benefits, so that's what I'm poking around on this forum to learn more about.  Thanks :-)

[Ralf11]

as an unwise member it seems that the 2 things you want are galvanic isolation and re-clocking

 

but it also seems that neither is needed for certain high quality DACs

 

What-HiFi thought this DAC was xlnt. at first and a few years later only got 3/5 due to newer designs

 

how many pennies do you want to put into a new DAC or add-ons vs. new speakers?

[DavidFaik]

Scratching around various sources I have established that a Mac Mini 2012 will put out max 88khz (thus for most people 2x the 44,.1 khz of most music flies) from it's built in SPDIF.  Also max 16bit.  I will check this over the weekend.  Models 2010 and before max at 48Khz and some later models hit the heady heights of 96Khz.  Also then saw that my pure music was set at 44.1 Khz, so when I swapped to SPDIF it probably wasn't doubling the KHz in upsample.  That said, I'm still completely scratching my head as to why selecting "upsample"  did actually audibly improve the sound quality, since it clearly wasn't upsampling ? 

 

So, I think this means that I either need a good USB to coax/ spdif adapter to allow me to upsample in Pure Music to higher levels.  Or to buy a new DAC with 32bit 384khz DSD and such wonders built in.

 

Ralf11, thanks for your comments!!! I'm in no rush to part with hard earned cash, but think this means I need to figure the relative value of a USB->coax (or balanced) that would allow me to upsample and deliver an easy processing load to my fairly decent DACs (namely 192Mhz / 24 bit) OR buy a new DAC.  I think the latter would be my choice if the USB->coax started costing round half the new DAC.  I'm wondering if said converters also help with regards to jitter, isolation and reclocking?  Also if the clocking in PureMusic isn't pretty good anyway?  Ideally I'd like any such converter to power from USB and certainly not to have a noisy wall wart plug (I invested in good power cables and interconnects to adding noise with a crappy psu would hurt LOL).  The gadget that I was aware of was the now discontinued Musical Fidelity V-Link 192, which seems suitably small and self powered.  Don't see many popping up 2nd hand though.  Would be very open to any advice or experience said gadgets?

 

For a new DAC if that was the path, I'm now seeing some discounting of prices on the Audiolab MDAC Plus, guessing as they are now aging a little (2016 model).  USB does 32-bit/384kHz, handles DSD (that I don't currently own) and generally seems up there with the higher specified DACs.  Or maybe would want to see if I could hear the older version of the Hugo TT (as the small RCA connectors on the Hugo seem to be a show stopper).  I'd really need to do more research as I'm hopelessly out of date DAC wise. I'd not look to change the speakers, as I think that they are one of the stronger elements in my set, so am focused on bettering the source.

 

 

[Panelhead]

 You have to allow upsampling. It is in the drop downs at the top. 

  I think PM can detect the maximum sample rate and will not allow upsampling higher than the dac can accept. But some dacs do accept higher rates than specified. 

  I normally upsample to the highest rate the dac will accept. The highest I own goes to 384K.

[DavidFaik]

Hi Panelhead!  Thanks for the reply.

I discovered a few things in my stumbling along journey:

 

1. that I had to change midi settings to the upsample rate as well

2. that the spdif output on the Mac mini doesn’t seem to go higher than 88mhz

3. that - when all else is correct - the upsampling in Pure Audio doesn’t improve 44khz tracks, best left in my case to the DAC to upsample.  Maybe as the DACs upsample to 192 and it’s better to do all the upsampling once / in one place?

4. my Musical Fidelity DAC in this system completely wipes the floor with my Audiolab MDAC, despite the rave reviews when it was out and the higher specs (it can do 96khz on usb vs 48khz). The MF DAC sounds nearly high end and the Audiolab sounds hifi

 

I think based on the above I’ll be sticking to 44khz high res like Apple Lossless. Changing the midi and rebooting the computer to play a few tracks at a higher kHz doesn’t cut it for me in terms of practicality.

 

I may look at a streamer and a high Rez music service to see if there is anything to be had from tracks at higher kHz, as these seem easier in use (no midi settings to keep fiddling about with)

 

Curious if your 384k DAC is upsampling or if you have found an easy way to play high res files that are not 44k?