[grizzlybeast]

I posted this in the Compass thread, maybe some will find it helpful:
FYI, I've been contemplating whether to go with the Compass2 or NFB28 and I've discussed this with Kingwa to a great length (much kudos to him). I've come to the following conclusions:

- In single-ended use they're very similar
- The NFB28 has the benefit of a balanced design, enabling one to use balanced inputs (RCA vs XLR related differences) and balanced output (which in theory should make the headphone sound a bit better and more controlled + the balanced design of the amp, which should make the amp section a bit better)
- The balanced output is basically the one thing that makes the NFB28 better (single ended vs balanced termination)
- NFB28 uses digital relay controls and digital volume control, which he says is better even sonically, I personally like ALPS analogue volume pots just as much and not really sure about sonic merits
- NFB28 uses an R-core transformer while the C2 uses a smaller 'high quality' 45W transformer. No idea if that makes a difference
- DAC section is identical
C2 has a line in through an op-amp, NFB28 has a direct input.
- With the stock op-amp, difference should be small if any (my guess)
- C2 can roll DACs and op-amps for line in, NFB28 cannot
- Both have plenty of power to drive everything short of the HE-6

In the end because I went with the Compass because going balanced would mean further investments (cables or even sources or converters) and without using the balanced output the difference is 'slight' since the DAC and single-ended amp sections are ialmost dentical. (C2 is slightly more powerful even).

In conclusion if you are ready for balanced get the NFB28 (or upper models), if you roll single-ended (I only utilize the USB in and line in and a SE output is more viable for me cause most headphones come like that... Retermunatiom or balanced cables = money over budget...) spring for the C2.

Both amazing units for the price

Do u mean plenty of power for everything short of the he6 in single ended use? Or balanced as well?

Though one is on its way I remember reading somewhere that a similarly specified agd amp didn't power the he6 enough. They didn't mention if they used it balanced or not.

 

[conquerator2]

Do u mean plenty of power for everything short of the he6 in single ended use? Or balanced as well?

Though one is on its way I remember reading somewhere that a similarly specified agd amp didn't power the he6 enough. They didn't mention if they used it balanced or not.

Even in SE use ( the NFB28 has a bit less power there though so balanced with it is better)
Anything short of HE-6, Abys and K1000, etc.
MLE tested the C2 with the HE-4 and it drove it well.

 

[grizzlybeast]

I guess I am apprehensive because though I have one coming in, people in the "amps that can drive the he6..." posted that the slightly more powerful 10ES didnt provide enough power for the he6. But Specs show plenty. Maybe Ill be the first to have them paired together?

 to report back atleast.

 

[sayh]

I guess I am apprehensive because though I have one coming in, people in the "amps that can drive the he6..." posted that the slightly more powerful 10ES didnt provide enough power for the he6. But Specs show plenty. Maybe Ill be the first to have them paired together?  to report back atleast.

Both 10es and nfb28 have enough power and will drive he6 well enough in se or balanced. Definitely louder and better driven in balanced mode, with 10es sounded more sparkly with he6 with certain genres of music.

 

[grizzlybeast]

^THANKS a ton I'll take your word for it while I wait to get here.

 

[DaemonSire]

I've posted this in the NFB-3 thread as well, but wanted to get your take on this too since the NFB-3 and NFB-28 uses a similar design in its DAC stage.
 
As I'm putting my NFB-3 through the paces and testing the ins-and-outs of all the functionality, I've discovered something.  I sent Kingwa a message on Sunday but waiting to hear back from him.
 
This is related to the USB32, optical input and relay click.  I've noticed that if I send an optical signal to the unit, the USB32 cannot override the sample rate.  Essentially it is locking the unit at whatever sample rate the optical is sending it.
 
I've discovered this when I had the optical out from my soundcard connected to the optical in, and using the USB32 input at the same time.  Without the optical connected, anytime I would play/stop a song, or switch songs to different sample rates (44.1kHz, 96kHz, etc.), the internal relay would click letting me know it is switching.  However, if I turn the optical source, I can hear the relay in the unit click (even though it isn't even on Optical) and then the USB32 never clicks.  I can switch between different sample rates all day and no relay click whatsoever.
 
If I shut off the optical source, the USB32 does its normal relay click as expected.
 
This is what makes me believe it gets stuck at using whatever sample rate the Optical Source is, regardless of the USB32 input.
 
As another test, I used my PS3 as the optical input as well.  As soon as I turn the PS3 on, the relay clicks (syncing it to the PS3), and then it never clicks again when using the USB32.  If I turn the PS3 off, everything is back to normal.
 
This behaviour doesn't happen over the Coax input.  Coax input functions exactly as expected.
 
Now, the sound still does come through the USB32 input fine with an optical source on, but I would rather it be playing bitperfect and not resampled.
 
Can anyone confirm/deny this behaviour?  I hope it isn't a wider spread issue.
 
I will update when I hear back from Kingwa.
 
Thanks

 

[conquerator2]

I've posted this in the NFB-3 thread as well, but wanted to get your take on this too since the NFB-3 and NFB-28 uses a similar design in its DAC stage.

As I'm putting my NFB-3 through the paces and testing the ins-and-outs of all the functionality, I've discovered something.  I sent Kingwa a message on Sunday but waiting to hear back from him.

This is related to the USB32, optical input and relay click.  I've noticed that if I send an optical signal to the unit, the USB32 cannot override the sample rate.  Essentially it is locking the unit at whatever sample rate the optical is sending it.

I've discovered this when I had the optical out from my soundcard connected to the optical in, and using the USB32 input at the same time.  Without the optical connected, anytime I would play/stop a song, or switch songs to different sample rates (44.1kHz, 96kHz, etc.), the internal relay would click letting me know it is switching.  However, i[COLOR=222222]f I turn the optical source, I can hear the relay in the unit click (even though it isn't even on Optical) and then the USB32 [/COLOR][COLOR=222222]never[/COLOR] clicks[COLOR=222222].  I can switch between different sample rates all day and no relay click whatsoever.[/COLOR]

[COLOR=222222]If I shut off the optical source, the USB32 does its normal relay click as expected.[/COLOR]

[COLOR=222222]This is what makes me believe it gets stuck at using whatever sample rate the Optical Source is, regardless of the USB32 input.[/COLOR]
[COLOR=222222] [/COLOR]
[COLOR=222222]As another test, I used my PS3 as the optical input as well.  As soon as I turn the PS3 on, the relay clicks (syncing it to the PS3), and then it never clicks again when using the USB32.  If I turn the PS3 off, everything is back to normal.[/COLOR]
[COLOR=222222] [/COLOR]
[COLOR=222222]This behaviour doesn't happen over the Coax input.  Coax input functions exactly as expected.[/COLOR]
[COLOR=222222] [/COLOR]
[COLOR=222222]Now, the sound still does come through the USB32 input fine with an optical source on, but I would rather it be playing bitperfect and not resampled.[/COLOR]
[COLOR=222222] [/COLOR]
[COLOR=222222]Can anyone confirm/deny this behaviour?  I hope it isn't a wider spread issue.[/COLOR]
[COLOR=222222] [/COLOR]
[COLOR=222222]I will update when I hear back from Kingwa.[/COLOR]
[COLOR=222222] [/COLOR]
[COLOR=222222]Thanks[/COLOR]

I imagine it is.

For me, the RCA in on the Compass2 does the same thing.
There's a button to make the line in activate or deactivate and it does not work properly with the USB in.
To use the USB in I have to switch to a different input (coax or optical) and only then change to the line in input as it doesn't work on USB in whenever the sample rate is different (for example 44.1 on the PS3 line in and 48 via USB)
Which is strange because line in is a purely analogue input so it shouldn't interfere with USB...

It's a different problem perhaps but I am positive it's because of the relay unit not doing it's job perfectly...

 

[Clemmaster]

Did you try playing a 48 or 96 content with the unit locked at 44.1? Is the sound slower?

 

[DaemonSire]

Did you try playing a 48 or 96 content with the unit locked at 44.1? Is the sound slower?

 
No it isn't.  I set the PS3 to use either 44.1 or 48, and then played some 96 content via USB and it sounded normal.
 
So maybe it isn't being locked at the specific sample rate but is bypassing the muting relay?

 

[Clemmaster]

I don't think the USB-32 would resample the data (does it have a processor?) so if it plays fine with any sample rate, then it is a mineur issue.

 

[DaemonSire]

I don't think the USB-32 would resample the data (does it have a processor?) so if it plays fine with any sample rate, then it is a mineur issue.

Even if it doesn't resample, it still isn't working properly.  Without the muting relay, there is a loud pop when switching around DSD tracks.  Because the Optical input is blocking that muting relay, there is that pop now.
 
I don't have too many DSD tracks (really other than testing), but it is annoying.  Especially for the price of these units...

 

[elwappo99]

  I guess I am apprehensive because though I have one coming in, people in the "amps that can drive the he6..." posted that the slightly more powerful 10ES didnt provide enough power for the he6. But Specs show plenty. Maybe Ill be the first to have them paired together?

 to report back atleast.

 
I had the NFB-10SE for quite some time actually. I found that it did a pretty good job for a headphone amp. It got most music up to OK volumes, but if there was a recording that wasn't cranked up in mastering, I had the volume maxed out and on high gain most of the time. 
 
These are really stellar units though. So much functionality shoved into one box, and with so much SQ is really a bargain.

 

[grizzlybeast]

 
I guess I am apprehensive because though I have one coming in, people in the "amps that can drive the he6..." posted that the slightly more powerful 10ES didnt provide enough power for the he6. But Specs show plenty. Maybe Ill be the first to have them paired together?  to report back atleast.

I had the NFB-10SE for quite some time actually. I found that it did a pretty good job for a headphone amp. It got most music up to OK volumes, but if there was a recording that wasn't cranked up in mastering, I had the volume maxed out and on high gain most of the time. 

These are really stellar units though. So much functionality shoved into one box, and with so much SQ is really a bargain.

And you had the volume maxed out on high gain while using the balanced out right?
If I run into that the. I will most likely get a good speaker amp and sell this. I am stubborn about headroom.

 

[elwappo99]

 

 

 
I guess I am apprehensive because though I have one coming in, people in the "amps that can drive the he6..." posted that the slightly more powerful 10ES didnt provide enough power for the he6. But Specs show plenty. Maybe Ill be the first to have them paired together?

 to report back atleast.

I had the NFB-10SE for quite some time actually. I found that it did a pretty good job for a headphone amp. It got most music up to OK volumes, but if there was a recording that wasn't cranked up in mastering, I had the volume maxed out and on high gain most of the time. 

These are really stellar units though. So much functionality shoved into one box, and with so much SQ is really a bargain.

This is all balanced right?

 
Oh yea. I didn't think it did so well SE. Of course all of this was using the older, NFB-10SE, and IMHO.
 
EDIT: Forgot to add, I thought the HE-500 and HE-400 were both really spectacular on the NFB-10SE. The increased performance of having a balanced amplifier really shone through. 

 

[conquerator2]

Oh yea. I didn't think it did so well SE. Of course all of this was using the older, NFB-10SE, and IMHO.

EDIT: Forgot to add, I thought the HE-500 and HE-400 were both really spectacular on the NFB-10SE. The increased performance of having a balanced amplifier really shone through. 

Too bad I couldn't read this a week ago when I was buying the Compass2 specifically for the HE-560
Regardless, it's still what it is - a good solid 3w SE DAC/amp