Re: Bit test on Bluesound Node2i and two types of digital cable

If you use the Node 2i as a transport you're losing MQA... for me it matters but not for everybody.

Re: Bit test on Bluesound Node2i and two types of digital cable

tubeaudio wrote:

If you use the Node 2i as a transport you're losing MQA... for me it matters but not for everybody.

I will not be using MQA by design. I wrote about this here:

https://forum.audiogon.com/discussions/ … ical-music

53

Re: Bit test on Bluesound Node2i and two types of digital cable

Ghjuvanni wrote:

BTW, I am curious why the +6dBu on balanced output?

That comes automatically, as explained by Basken. Missing is only the note that this is standard on nearly any HiFi unit that has XLR outputs. They are always 6 dB higher in level. And because that is 'normal' it should not be necessary to point out and explain.

Regards
Matthias Carstens
RME

Re: Bit test on Bluesound Node2i and two types of digital cable

MC wrote:
Ghjuvanni wrote:

BTW, I am curious why the +6dBu on balanced output?

That comes automatically, as explained by Basken. Missing is only the note that this is standard on nearly any HiFi unit that has XLR outputs. They are always 6 dB higher in level. And because that is 'normal' it should not be necessary to point out and explain.

@MC I agree this is not strictly necessary -- but it would be helpful. Misunderstandings are possible for people new to XLR. Better to err on the side of more information. If it wasn't for the answer on the Polish audiostrereo.pl forum I would have gone on the wrong path of cable improvements. FYI, it wasn't before a lot of anti-audiophile-myth ammunition was fired on both forums, that a correct technical answer was provided. 
If you google for XLR and 6 dB, you'll see there is a lot of Q & A. Here's an example, and a good answer:

https://homerecording.com/bbs/general-d … ter-310133

An electrically balanced output will increase signal level by 6dB. Let's say you have a signal that is 3V (really the voltage changes constantly, but play along). An electrically balanced output will take that output signal and invert it to -3V. Then it sends both those signals down the line to the next bit of kit.

The receiving amplifier is differential, which means it will output the difference between its two inputs. The difference between 3V and -3V is 6V, so your signal is now 6V, which is 6dB hotter than 3V, according to this formula:

dB = 20 * log (6 / 3)

Note that only electrically balanced outputs do that, the other two types of balanced outputs (impedance balanced and transformer balanced) do not.

Also, the 6dB increase becomes self-limiting because if there were no other gain changes made then each bit of kit would have to have 6dB more headroom than the previous bit--which is not realistic (even if manufacturers knew the exact order of your chain, which they cannot). So when you have an electrically balanced output, you will usually have to compensate by reducing level somewhere.

Depending on where that happens it can actually degrade signal-to-noise, but it's a small enough change that it probably doesn't make a noticeable difference. Generally, noise is dominated by earlier stages, so the electrically balanced output's noise contribution should be negligible. However, if you run into a headroom problem at the receiving gear, it's ideally best to reduce level in between them, or at least at the output of the earlier device rather than its input.

Again, probably doesn't make a noticeable difference. Just plug things in and enjoy

Re: Bit test on Bluesound Node2i and two types of digital cable

Ghjuvanni wrote:

@MC I agree this is not strictly necessary -- but it would be helpful. Misunderstandings are possible for people new to XLR.

I guess the point MC is trying to make is, that if a unit features an XLR input/output it is expected to handle common XLR signal-levels, or at the very least specify acceptable levels in the manual - and it would seem your amp does neither.

In fact - the M6si manual states:

"The unit features a finely tuned and tweaked preamplifier, for smooth sound coupled with low noise and virtually no distortion."

Ghjuvanni wrote:

FYI, it wasn't before a lot of anti-audiophile-myth ammunition was fired on both forums, that a correct technical answer was provided.

Well - you'll have to concede that it was never the quality of the cables, but rather what i would characterize as a "design-flaw" of the amp .. or at the very least an omission of operational information essential to extracting the full performance of the amp that was the culprit - and honestly, considering the $$$ of that pre-amp i would take the issue up with the manufacturer of said amp!

Ghjuvanni wrote:

If you google .. <snip>

.. you will find (technical) answers - but - what could possibly benefit the "spirit" as well as sanity of this forum, might be an elaborate and living FAQ / Wiki, addressing some of the repeat questions from new owners of the ADI-2 Pro / DAC - in a way that that is respectful yet factually and verifiably accurate, which should hopefully satisfy everyone.

Fruit for thought ..

Best,
Basken

Rune Borup @ FishCorp
Producer / Engineer / Composer
RayDAT > 2 x ADI-8 QS | AES+SPDIF > ADI-2 Pro

56 (edited by N00b 2020-02-02 23:04:43)

Re: Bit test on Bluesound Node2i and two types of digital cable

Basken wrote:
Ghjuvanni wrote:

@MC I agree this is not strictly necessary -- but it would be helpful. Misunderstandings are possible for people new to XLR.

I guess the point MC is trying to make is, that if a unit features an XLR input/output it is expected to handle common XLR signal-levels, or at the very least specify acceptable levels in the manual - and it would seem your amp does neither.

In fact - the M6si manual states:

"The unit features a finely tuned and tweaked preamplifier, for smooth sound coupled with low noise and virtually no distortion."

Ghjuvanni wrote:

FYI, it wasn't before a lot of anti-audiophile-myth ammunition was fired on both forums, that a correct technical answer was provided.

Well - you'll have to concede that it was never the quality of the cables, but rather what i would characterize as a "design-flaw" of the amp .. or at the very least an omission of operational information essential to extracting the full performance of the amp that was the culprit - and honestly, considering the $$$ of that pre-amp i would take the issue up with the manufacturer of said amp!
[...]

Indeed. No problem with my former Cambridge CXA-80 amp at +13 dBu via (cheap) XLR...

ADI-2 DAC (with stock PSU) - Neumann KH 310 A monitors - Cheap USB and XLR cables