[zilch0md]

Thanks for this bit of research you posted in March of 2013, songmic!

I just ordered the MK1.

... which was listed as available, but turned out to be not in stock, so I've ordered the MKII, instead.

When it arrives, I'll write a gushing first impression guaranteed to be incredible.

 

[zilch0md]

Do any of you Octave MK1 or MKII users upsample 44.1 to 88.2 in a PC before playing via this DAC?

If so, what are the benefits?

Thanks,

Mike

 

[Sorrodje]

Yes I do. No hearable benefit for me but I didn't try serious comparison

 

[zilch0md]

Thanks! Do you upsample routinely or did you just try it as a casual test?

I've read of NOS fans doing this for the purpose of overcoming a 3dB fall-off to 20kHz when playing 44.1 files.

Was that your motivation? (I know I wouldn't be able to hear any difference that high.)

 

[Sorrodje]

Thanks! Do you upsample routinely or did you just try it as a casual test?

I've read of NOS fans doing this for the purpose of overcoming a 3dB fall-off to 20kHz when playing 44.1 files.

Was that your motivation? (I know I wouldn't be able to hear any difference that high.)

 
 
I upsample routinely. I'm using Linux and Pulseaudio so I configured pulse to generate a 24bits/96khz PCM
 
My motivation was to avoid this treble roll off on order to be sure I don't alterate the neutrality of the dac.

 

[zilch0md]

I am unfamiliar with Pulseaudio - have you configured it to upsample on the fly, so to speak, or are you storing previously upsampled files?
 
Thanks very much for your replies.

 

[Sorrodje]

On the fly. I have very few  HD files.
 
Funnily. I'm currently using antoher dac you had : the Bushmaster mkII . Seems we're lurking around the same pieces of gear

 

[zilch0md]

Yes, there's no accounting for our excellent taste!   

 
And I came very close to ordering a Sonnet 2, but decided to try tackling my HD800 with a good NOS DAC first, so my chain will still be more sterile than yours:
 
FiiO X5 Coaxial Out > Octave MKII > OPPO HA-1 amp, balanced out > unmodified HD800
 
---
 
Of interest to our discussion, above:  I received an email reply from Cees Ruijtenberg, having asked if there are any audible benefits to be enjoyed by using a PC to upsample from 44.1 kHz to 96 kHz in advance of playing a file through the Octave MkII.
 
I don't want to quote him directly without asking his permission, but paraphrasing, it boils down to this (my summary):  
 
1) Depending on the software used, upsampling can create pre- and post-ringing.
2) Artifacts can be created that give the impression of more detail, but it's not genuine.
3) It's best to use the original files.
4) If you want to experiment, however, 44.1 should be upsampled to 88.2 or 176.4, not to 96 or 192.
 
In my original query, I hadn't mentioned anything about doing this to compensate the 3 dB at 20kHz attenuation that I've read some NOS DACs suffer.  I had only asked if there is any audible benefit to upsampling with something like dbPoweramp - for the Octave MkII.  Apparently, Cees feels it's best not to do so.
 
By the way, Cees responded very quickly to my email. It's great to have direct access to the designer. I'm humbled and impressed.
 
Mike

 

[zilch0md]

It's here!  
 

 

[Argo Duck]

^ Yes I've seen comment elsewhere on HF that there's good reason to use whole multiples of 2 when up-sampling. IIIRC Jason (Schiit) discussed it, among others.

 

[zilch0md]

Not quite two hours out of the box, the Octave MkII is already doing wonderful things with the unmodified HD800 on a neutral amp (OPPO HA-1 or even the DACmini CX with 1-Ohm output impedance mod). It has smooth yet still detailed treble, terrific separation, with everything sounding very natural. That's the part that's the biggest jaw-dropper. I'm listening to Jennifer Warnes at the moment. Dynamics are awesome. It is WAY nicer than the ESS9018 in the HA-1 > HD800 (for my tastes).  Me thinks I can actually listen to the HD800 for a few hours now, without fatigue, but that's just the half of it. Enough gushing, for now...

 

[Sorrodje]

  Yes, there's no accounting for our excellent taste!   

 
And I came very close to ordering a Sonnet 2, but decided to try tackling my HD800 with a good NOS DAC first, so my chain will still be more sterile than yours:
 
FiiO X5 Coaxial Out > Octave MKII > OPPO HA-1 amp, balanced out > unmodified HD800
 
---
 
Of interest to our discussion, above:  I received an email reply from Cees Ruijtenberg, having asked if there are any audible benefits to be enjoyed by using a PC to upsample from 44.1 kHz to 96 kHz in advance of playing a file through the Octave MkII.
 
I don't want to quote him directly without asking his permission, but paraphrasing, it boils down to this (my summary):  
 
1) Depending on the software used, upsampling can create pre- and post-ringing.
2) Artifacts can be created that give the impression of more detail, but it's not genuine.
3) It's best to use the original files.
4) If you want to experiment, however, 44.1 should be upsampled to 88.2 or 176.4, not to 96 or 192.
 
In my original query, I hadn't mentioned anything about doing this to compensate the 3 dB at 20kHz attenuation that I've read some NOS DACs suffer.  I had only asked if there is any audible benefit to upsampling with something like dbPoweramp - for the Octave MkII.  Apparently, Cees feels it's best not to do so.
 
By the way, Cees responded very quickly to my email. It's great to have direct access to the designer. I'm humbled and impressed.
 
Mike

 
Yep.  I've read pages and pages about the subject. I often read that 88,2 upsampling is better . 
 
I know it's possible ti choose the resampling algorythm in Pulsaudio and the level of "quality" . but after talking with some people here or there , we all doubt that anybody could hear IRL the bad effect of even the worst level quality of upsampling. Maybe i'm wrong. so Ieft the default setting to keep my CPU consumption low enough.
 
For th treble roll off, it has been measured and charts are explicits here : http://www.head-fi.org/t/561674/metrum-acoustics-octave/165#post_8602241
 
So after many hesitations, Ive choosen to upsample.
 
That been said I think I'm splitting hairs

. All these setting have no hearable effects I can detect

 

[zilch0md]

LOL
 
If you're like me, though, "knowing" that there's an advantage is enough for me to lock onto something, whether I can hear the advantage or not. 

  
 
It's kind of like blind faith, but if there's a lot of evidence saying "this is better,"  I do it.  
 
Thanks for that link. If indeed the Metrum Octave MkII has so great a roll-off, I know from being tested by an audiologist less than a year ago, that I'm good up to 12k, where my loss only just starts to kick in - right on schedule for my age.  So that might be why I'm not "hearing" rolled-off highs.  Oddly, I have no tolerance for sibilance or otherwise "bad" treble - which suggests my hearing isn't all that bad.  After all, how much content actually resides at 15k or higher in most recordings?  
 

 
Mike

 

[Sorrodje]

I'm on the same boat. So I definitely can't advice to upsample or not.   At 43 years old I don't hear anything above 15 Khz so I really don't really care

 

[hans030390]

Keep in mind that while the roll-off may be -3dB or so at 20KHz, it'll be between -0.5-0.75dB at 10KHz and about -1.5dB at 15KHz. Given most music, the performance of most headphones, and the average hearing ability, this isn't much to worry about.
 
I spent a lot of time playing around with upsampling methods when I had my Metrum DACs on hand. HQPlayer is fun to mess with, because it lets you try a bunch of different upsampling filters. Some are linear phase, some are minimum phase, and they all have varying amounts of pre and/or post ringing. I think it has a couple filters that aren't supposed to have filter ringing. If you're using a Mac, I think there's a known good audio player with different upsampling filters available. Common upsamplers seem to use linear phase, IME. The more you play around and test various filters, the more you might be able to hear the sound they impart on the DAC (and the Metrums acted as a good "template" to test how these filters sound, in a sense). Yes, you'll likely get a better sense of clarity and detail with upsampling, but whether or not you'll prefer that is up to you. I decided I just preferred NOS on everything, even 16/44.1.
 
It's expensive and ugly as sin, but XXHighEnd supposedly has a good upsampler designed for NOS DACs (the Phasure DAC, in particular). I believe it avoids filter ringing.
 
Upsampling will bring some other measurable benefits to the table outside of the frequency response (much like playing higher bit-rate and sampling rate files will improve NOS performance to an extent), but, again, it really comes down to what your ears hear as most pleasing.