[holland]

 
Quote:

I admit I am not knowledgable enough to know, but according to the website, it states that low impedance phones use the diamond output stage. So is it possible that it is sensing the load and rerouting the output? I believe that is how the new Schiit Lyr is going to operate. Or is the website just saying that the diamond output stage is always there, but especially to help low impedance phones which need more current?
 
"For low impedance, we applied a diamond output stage which is quite less colored than most conventional circuits."
 

That's low impedance, not low gain.  I think they mean low output impedance, particularly with no global feedback.  The diamond buffer is a good circuit with low output impedance.  It's possible they bypassed the ACSS and have the DAC directly connect to the pot...but I never get that impression in their specs.
 
Quote:

Chinese New Year just started today soo i doubt you'll get a response soon.

Kung Hei Fat Choi!

Chúc Mừng Năm Mớ!

Happy New Year!

 

[migman]

I won't pretend to understand the technical but interesting conversation of the last few pages, so I will just give my impressions so far of the NFB-12.  I received mine yesterday and was able to spend about an hour listening to a CD I know well (the soundtrack to Jurassic Park).  The associated equipment I was listening on is as follows:
 
Sony DVP-NS999ES CD/SACD/DVD player
NFB-12
Yamaha RX-V692 receiver circa 1997
ATH-M50 headphones (via Yamaha headphone jack)
 
The Yamaha is being fed analog outs from both the NFB-12 and the Sony.  This allows me to rapidly compare the DAC in the NFB-12 to the DAC in the Sony (which in my understanding is quite good).  Initially I just want to see if I can discern the difference between the Sony's DAC and the NFB-12 which is why I am connected to the Yamaha's headphone jack.  After matching the levels as close as possible I listened to some of my favorite tracks on the JP soundtrack multiple times.  Granted this was right out of the box and my listening time was short, but to me the NFB-12 and the Sony sound virtually identical.  The Sony might be a hair brighter with a little tighter bass, but it is very close.  I will be doing more listening tonight with some other pieces.  Also, I have a pair of Kenwood KH-K1000 headphones on the way which I hope should be more revealing than the M50s.  So far I am very happy with the NFB-12.

 

[tim3320070]

Can everyone wait a couple of weeks before commenting? The gear needs run-in and initial impressions only muddy the water.
Stuck record here.

 

[Poetik]

I Just got mine today and I like it so far.  I'd say from the initial "non burn in" the sound stage isn't quite as expansive as my HDP (width wise) but I can hear the details in the music quite a bit better with the NFB-12 (better instrument separation and placement).  Also so far the NFB-12's bass isn't as tight as the HDP either.  I'm sure my impressions will change after it burns in for a few weeks but we'll see. 
 
So far I feel the HDP > NFB-12 for the fact that it immerses me in the music a bit more with it's sound stage and tighter bass.  If the NFB-12's bass tightens and it's sound stage opens a little bit more  then it'll be enough to sway me to sell the HDP.  I'll be sure to come back and update after I get a couple weeks of burn in on it. 
 
Also I know there's a lot of technical talk going on and how some graphs don't show a "favorable" result.  Honestly I didn't understand a single graph that was posted but it is an objective way way to look at it.  However when you want to test a piece of gear that's made for your ear then you should place more importance on actually listening to it.  For anyone that's thinking of getting the NFB-12 it's a great deal for the price so please don't be afraid to try it because of some miscellaneous graphs. 

 

[Kassem]

After everyone gets nice and burned in I'd personally like to know how this thing sounds with DT880 and various Grado products.

 

[Slaughter]

No
 
Quote:

Can everyone wait a couple of weeks before commenting? The gear needs run-in and initial impressions only muddy the water.
Stuck record here.

 

[madwolf]

 
 
Quote:

 
Quote:

olf /img/forum/go_quote.gif

Pin 4 is 0 volts, Pin 22 is 3.5V and Pin 24 (Hardware/software) is at 0 volts.
 
So yes it is hardware mode.  
 

 
Great, thanks.  The input rate is set for 192KHz and using the default linear filter mode.  From what I understand, changing Pin4 to floating and remove the pull-down resistor would offer a better filter than the default linear filter.  This would sacrifice some phase linearity for better time domain.  The roll-off is the same, but it is to eliminate pre-ringing.  The roll-off is to eliminate post-ringing.
 
I'm curious to see what the sweeps look like with an upsampled 192KHz sample rate, since oversampling is set for a 192KHz stream in the chip, so the chip is really expecting 192KHz data and the filters are set for high frequency data vs 44.1KHz.
 
Ayre whitepaper
 
Too bad there are no switches or jumpers to play with the filters.
 
Also note that if oversampling is disabled and the input stream to the DAC is 44.1KHz or 48KHz, the filters where the corner rate is normally around 30KHz moves to 15KHz.  This is *exactly* what the RMAA has shown.  By extension, if you provide an upsampled stream, the sound will change.

I did some more measurement Pin 22 is directly connected to Pin 8 the Digital Plus supply, 0 Ohm between the 2 pins. 
Pin4 the filter select pin is directly connect to Pin 7. 0 Ohm There is no pull down resistor. 
So the only way to mod this is to lift the pin from the board. And that is exactly what I did for Pin 22 on both Wolfson 8741

 
By lifting Pin 22 (The voltage is now 1.7V) The oversampling is now at 96Khz. 
I could connect this pin to ground, float or Digital Vcc to select the different frequency. 
 

 
Quote:

Quote:

 
Even cheap HDA codecs integrated in computer mainboards don't exhibit this kind of problems those days.
If you upsample before sending to the DAC, the performance is honorable. If you use a CD player outputing 44100Hz signal, the performance is just crap.
 
Looks like someone didn't do its homework in audio testing, or my amp is misconfigured?

It's set up incorrectly.  It's an easy fix though, setting 1 pin properly, though I would change the filter to be the minimum phase filter instead of the linear.  I'd take phase distortion over edginess any day of the week, as per the Ayre whitepaper.  If you really want to have flexibility you need to add parts.  You'd need an ASRC, but I would run the DAC at 96KHz instead of 192KHz, because the WM8741 runs better at 96KHz instead of 192KHz.  In 192KHz it runs at 128Fs instead of 256Fs.  I might build an ASRC module when I get mine in March or just set it to 44.1KHz and the minimum phase filter.
 
Nice job on running the tests.  The issue is that the DAC is told the input stream is 192KHz, and it simply is not.
 
Email KingWa the data.  I'd wait a little longer for an ASRC implementation, or at least a 2 3-way switches in the back to select the HW filter mode and the HW sampling rate.

 
A 3 way switch would be nice, But I think some jumpers could be easier here. It not very often then you change the source sampling frequency. 
My unit comes with 5 jumpers (someone else reported 10) maybe I am fated to use jumpers to fix this issue. (pun intended)
 
The cheapest and easiest solution would be to float pin 22 as shown above. With this solution the ability to run at 192 is gone. but so far I do not have anything recorded at 192Khz so it not a big loss. 
 
ASRC may not be needed if there is a pin indicating what the source freq. But I could not find it on the 8805. It seem to be inside a register.....
 
From supercurio graph if the source is half the freq of the sampling freq it is still relatively flat to 20khz, so it might be an all in one solution. 
 
Using 44khz as a source as a comparison after lifting pin 22 the spectrum did open up and the sound is not so dark anymore. (Maybe some placebo since I am expecting this)
I only have a dual trace o-silly-scope at home. (measure the amplitude of 20Khz test waves at both setting ? ) Suggest please.
 
 
I need to borrow some equipment to test this out. 
 
 
Quote:

 
Even cheap HDA codecs integrated in computer mainboards don't exhibit this kind of problems those days.
If you upsample before sending to the DAC, the performance is honorable. If you use a CD player outputing 44100Hz signal, the performance is just crap.
 
Looks like someone didn't do its homework in audio testing, or my amp is misconfigured?

Maybe they only test with 192khz source, but thanks for the graph very helpful. I am an Android developer as well.  
 
I hope KingWa do not faint when he see this. 
Gong Xi Fa Cai

 

[Wen-Li]

Reading trough this Thread, and especially Slaughters and Elanzers Posts I have now decided to get a Beyerdynamics headphone.
The T1 is a tiny little bit out of my league tough So I settle for the DT880.
 
Now there are mutipple version of this yet again! D:
Oh well there seem to be enough threads about it...
 
Also the technical comments are very interesting altough I don't understand much. Thanks guys.

 

[Slaughter]

This amp has the volume for higher impedance phones like the 600 ohm Beyers, but I'm not sure it is best suited for them. This amp has crazy current, so the 32 or 250 ohm 880 might be a better fit for this amp. Might want to get some others thoughts on this though.
 
Quote:

Reading trough this Thread, and especially Slaughters and Elanzers Posts I have now decided to get a Beyerdynamics headphone.
The T1 is a tiny little bit out of my league tough So I settle for the DT880.
 
Now there are mutipple version of this yet again! D:
Oh well there seem to be enough threads about it...
 
Also the technical comments are very interesting altough I don't understand much. Thanks guys.

 

[cdanguyen08]

ive been offered a NFB 11 for 300. I intend to use this amp/dac for my HD 650 and k702. my question is that should i just take the NFB 11 or will the NFB 12 be fine enough.seeing how the price difference 60 dollars? and is the NFB 11 more suited for those headphones? had to sell my ibasso D2 for this new setup. only other amp/dac i have used

 

[Poetik]

Also I did try usb and toslink.  Toslink seemed to be a little clearer and had a wider sound stage. 

 

[Elanzer]

Quote:

ive been offered a NFB 11 for 300. I intend to use this amp/dac for my HD 650 and k702. my question is that should i just take the NFB 11 or will the NFB 12 be fine enough.seeing how the price difference 60 dollars? and is the NFB 11 more suited for those headphones? had to sell my ibasso D2 for this new setup. only other amp/dac i have used

I personally think the NFB-12 would be more suited for the K702, and NFB-11 more suited for the HD 650.

 

[Slaughter]

I could not detect any difference between USB and Coax.
 
Quote:

Also I did try usb and toslink.  Toslink seemed to be a little clearer and had a wider sound stage. 

 

[Poetik]

Quote:

I could not detect any difference between USB and Coax.
 
Quote:

Also I did try usb and toslink.  Toslink seemed to be a little clearer and had a wider sound stage. 

 

Different ears, different results.  Anyways it's been burning in so I'll have another go at it tonight. 

 

[BoyNamedSue]

It would be helpful to get other impressions of how the NFB-12 couples with the HD650. I personally think there is great synergy between the two - the sound is full bodied, dynamic, and very musically engaging. Its done a nice job of brining out the fun personality out of the HD650s which apparently is a latent/hidden characteristic of these phones. FYI, I have the HD650s with new drivers which may explain why I'm not getting the veil with them. 
 
Quote:

I personally think the NFB-12 would be more suited for the K702, and NFB-11 more suited for the HD 650.