[PleasantSounds]

I have recently purchased the NFB-5.2 to drive my Q701s when connected to a PC (Win7/64). To my ears it's a stunning combination and I'm enjoying every minute of using it, but within the gamut of possible choices between the file formats, players, drivers, connections and the DAC, I'm still experimenting to find the sweet spot. Here's what I have found so far:
- Audio file formats: I can hear a difference between 44.1, 48 and 96kHz, but 192kHz doesn't add any value to me. 24 bit sounds smoother than 16, albeit many recordings are ruined by clipping, and that's across the board. 320kps mp3 is as good as FLAC to my ears.
- Player: foobar2000 - mostly because of it's flexibility and ability to pass "pure" signal (however with some recordings this purity is reduced by the need to lower the volume to minimise clipping). But to be honest I haven't done extensive research on players.
- Driver: not much to choose in terms of driver software as usually all one's got is what comes with the motherboard or the soundcard. All you can do is make sure that the installed driver version works well (sometimes this could mean resisting upgrade to the newer one). However there are some driver settings that may have impact on the sound quality: the output port to be used and the default settings. Note that if you use WASAPI plugin these settings may have no impact any more. I'll discuss them in the next point
- Connection: I have tried all 3 of the USB/optical/coax and settled for USB 24bit/96kHz. To me it sounds a bit warmer than coax, with slightly cleaner bass, but I'm not sure if this is really optimal. For example, does this mean that all signals will be upsampled to 24/96 by the PC? In hardware or software? Even if so, this should be better than downsampling if I choose 16/44.1,  or even 24/48, right?
- Didn't see any difference between optical and coax (due to my preference for USB I wasn't trying really hard to compare these two).
- Filters: they do have impact, however very subtle. To me #3 sounds most pleasing.
- OPA: to me it only distorts the signal. Why not using equaliser instead?
- High gain setting sounds cleaner and I have an impression that it delivers slightly warmer sound but narrower soundstage, at the same volume levels
 
I'd be interested in comparing my observations with other users of the NFB5 in similar setups.

 

[Loquah]

I've just bought my NFB-5.2 and am loving it's power and sound quality to drive my Ultrasone HFI-680s. I've just organised to buy a pair of HD650s as well so can't wait to run it through it's paces with those.
 
So far the sound seems great. I am using it for my PS3 (via optical), cable TV (optical) and PC (USB) and it's doing a great job all round.
 
One concern I have is a nasty "crack" that comes through whenever I alter file details or settings (i.e. EQ) on my PC media manager (MediaMonkey). My USB soundcard/amp (Creative X-Fi HD) never did this so it's something to do with the NFB-5.2. Anyone else noticed this?
 
I'm using WASAPI drivers to output the sound. Should I stick with this or change to waveOut or MediaMonkey DirectSound?

 

[Loquah]

Does anyone know what the settings in the Audio-gd software do? These are the 2 settings options:
 

 

 
I figured these settings were handled by the media player (MediaMonkey in my case). Is that not so?

 

[PleasantSounds]

Quote:

Does anyone know what the settings in the Audio-gd software do? These are the 2 settings options:
 

 
 
 
I figured these settings were handled by the media player (MediaMonkey in my case). Is that not so?

 
As far as I can tell, this driver is supposed to enable USB to work at 192kHz - without it, Windows can handle up to 24/96kHz only.
Looks like it will do that for you - mine comes up greyed out (disabled) and set to 16/48kHz.

 

[PleasantSounds]

Quote:

One concern I have is a nasty "crack" that comes through whenever I alter file details or settings (i.e. EQ) on my PC media manager (MediaMonkey). My USB soundcard/amp (Creative X-Fi HD) never did this so it's something to do with the NFB-5.2. Anyone else noticed this?
 
I'm using WASAPI drivers to output the sound. Should I stick with this or change to waveOut or MediaMonkey DirectSound?

 
I have a feeling that this is related to WASAPI rather than the NFB-5.2. Have you used similar settings with the X-Fi? 

 

[Loquah]

I have a feeling that this is related to WASAPI rather than the NFB-5.2. Have you used similar settings with the X-Fi? 

I changed to DirectSound and it fixed it. Must be a driver compatibility thing. Same settings were fine on the X-Fi. Main thing is NFB-5.2 now running perfectly at 96 and 192 and sounding great!

 

[Loquah]

As far as I can tell, this driver is supposed to enable USB to work at 192kHz - without it, Windows can handle up to 24/96kHz only.
Looks like it will do that for you - mine comes up greyed out (disabled) and set to 16/48kHz.

You're right. It does let me choose 192kHz and it works beautifully. It seems to be dependent on the output driver used by the player. Maybe try a different player output driver and/or make sure your media player software is running when you open the Audio-gd config app. Any changes you make will require restarting your player to take effect.

A new question now: what's the benefit of upsampling to 192 if the tracks are at 44 or 96?

 

[PleasantSounds]

Quote:

You're right. It does let me choose 192kHz and it works beautifully. It seems to be dependent on the output driver used by the player. Maybe try a different player output driver and/or make sure your media player software is running when you open the Audio-gd config app. Any changes you make will require restarting your player to take effect.
A new question now: what's the benefit of upsampling to 192 if the tracks are at 44 or 96?

 
I'll give it a shot, however I suspect the problem is somewhere in the guts of Windows. Maybe reinstall the driver under the Administrator account rather than my user account will fix it.
 
Regarding upsampling to 192kHz: it could be bringing more issues than benefits - for example USB would have to pump much more data, and if you combine that with other things happening on your system like external disk access or printing, it may just saturate the bus and make the DAC to choke. Still - I'd like to be able to try it In theory a good upsampling algorithm can slightly improve the sound quality, so it may be worth a shot. In my experimenting I noticed that upsampling somewhat softens the clipping efefct, and that alone would be worth it.
 
Note that this shouldn't be an issue for coax/optical connections which are dedicated audio interfaces, while USB is shared. I just can't help that to me the USB sounds a bit richer...

 

[drez]

Quote:

 
I'll give it a shot, however I suspect the problem is somewhere in the guts of Windows. Maybe reinstall the driver under the Administrator account rather than my user account will fix it.
 
Regarding upsampling to 192kHz: it could be bringing more issues than benefits - for example USB would have to pump much more data, and if you combine that with other things happening on your system like external disk access or printing, it may just saturate the bus and make the DAC to choke. Still - I'd like to be able to try it In theory a good upsampling algorithm can slightly improve the sound quality, so it may be worth a shot. In my experimenting I noticed that upsampling somewhat softens the clipping efefct, and that alone would be worth it.
 
Note that this shouldn't be an issue for coax/optical connections which are dedicated audio interfaces, while USB is shared. I just can't help that to me the USB sounds a bit richer...

 
I like your thinking

.  I read somewhere that running more than 192 kHz can be counterproductive for some DAC chips: http://www.head-fi.org/t/588478/24-96-compared-to-24-192
The best recordings I have on my computer are 16/44.1 CD rips.  As you say streaming 24/192 puts more stress on the CPU, takes longer to read from the HDD, and uses up a greater proportion of the USB 2.0 bandwidth.
Realtime upsampling increases the load on the CPU even more - some use offline upsampling (ie upsample using a pro-audio software) but not many people tend to do this unless they have a NOS (nonn-oversampling) DAC.
USB is shared, but you can use separate USB controller/root hub for your keyboard, mouse etc and thereby avoid any potential problems.  
To be honest it is a shame that there are so few audiophile Firewire interfaces as Firewire has technical advantages, but maybe asynchronous USB levels the paying field...
 
@ Loquah The crack you are hearing is probably the audio stream restarting as necessary when settings are changed?  As long as it isn't happening when you aren't touching anything I think it's normal.

 

[john57]

[size=medium]If you are using professional recording software like cubebase, cakewalk and others you would use the ASIO driver since that driver operates at a lower level to the hardware and will have the lowest latency when recording multi instruments at the same time with the hardware you are using. Not a big need with a DAC only unit but you will be bypassing some of the software layers, like windows mixer to the device and lower latency. If you do not have an ASIO driver from the manufacture of your device you will then try the WASAPI driver which is the Microsoft version of ASIO. WASAPI in exclusive mode talks straight to the driver of the audio device and both ASIO and WASPI will give lower latency and best sound quality theoretically. With ASIO and the WASAPI driver you may not have windows software volume control and will have to rely on the device for sound level control.  With Directsound you have more audio software layers being used in windows OS for processing the audio. [/size]
 
Quote:

 
As far as I can tell, this driver is supposed to enable USB to work at 192kHz - without it, Windows can handle up to 24/96kHz only.
Looks like it will do that for you - mine comes up greyed out (disabled) and set to 16/48kHz.

 

[Loquah]

Quote:

 
I'll give it a shot, however I suspect the problem is somewhere in the guts of Windows. Maybe reinstall the driver under the Administrator account rather than my user account will fix it.
 
Regarding upsampling to 192kHz: it could be bringing more issues than benefits - for example USB would have to pump much more data, and if you combine that with other things happening on your system like external disk access or printing, it may just saturate the bus and make the DAC to choke. Still - I'd like to be able to try it In theory a good upsampling algorithm can slightly improve the sound quality, so it may be worth a shot. In my experimenting I noticed that upsampling somewhat softens the clipping efefct, and that alone would be worth it.
 
Note that this shouldn't be an issue for coax/optical connections which are dedicated audio interfaces, while USB is shared. I just can't help that to me the USB sounds a bit richer...

Just tried to change the Audio-gd app settings from 192 back to 96 after some of the other posts here (very informative - thank you everyone). When I tried the app, it was greyed out for me too. Need to make sure the device is connected via USB.
 
UPDATE: forgot that I'd unplugged the USB. Not sure which of these factors is involved, but seems to be one of or multiple of: USB connected, device switched on, media player running, output driver selected in media software.

 

[PleasantSounds]

Quote:

UPDATE: forgot that I'd unplugged the USB. Not sure which of these factors is involved, but seems to be one of or multiple of: USB connected, device switched on, media player running, output driver selected in media software.

 
That's a good hint - thanks!
Reinstalling the driver under admin account hasn't changed anything, but this sounds more logical.

 

[Loquah]

Quote:

 
That's a good hint - thanks!
Reinstalling the driver under admin account hasn't changed anything, but this sounds more logical.

 
I'm seriously thinking about creating a step-by-step guide by doing some trial-and-error testing. If I do one, I'll let you know and share it somewhere so others can benefit from my experimentation.

 

[PleasantSounds]

Quote:

[size=medium]If you are using professional recording software like cubebase, cakewalk and others you would use the ASIO driver since that driver operates at a lower level to the hardware and will have the lowest latency when recording multi instruments at the same time with the hardware you are using. Not a big need with a DAC only unit but you will be bypassing some of the software layers, like windows mixer to the device and lower latency. If you do not have an ASIO driver from the manufacture of your device you will then try the WASAPI driver which is the Microsoft version of ASIO. WASAPI in exclusive mode talks straight to the driver of the audio device and both ASIO and WASPI will give lower latency and best sound quality theoretically. With ASIO and the WASAPI driver you may not have windows software volume control and will have to rely on the device for sound level control.  With Directsound you have more audio software layers being used in windows OS for processing the audio. [/size]
 

 
Thanks for chiming in! I'm trying to put together in my head a cohesive picture of how these things are organised in Windows, and your message helps. But I have a few questions:
 
- Lower latency should mean faster response times. This may be true for ASIO, but playing with WASAPI I have an impression that the latency actually increases, for example reaction time to volume level changes becomes noticeable. Or are you talking about something different? If so, then what causes this delay?
 
- My understanding of WASAPI is, as the name says - an API, or a programming interface. It allows direct access to the sound driver, bypassing the Windows sound control layer (which contains volume control, among other things). What comes with foobar and other players as WASAPI module is a kind of adaptor that replaces the DirectSound calls with WASAPI calls. In that sense the term "driver" is a bit confusing, as we commonly associate it with code that integrates hardware with operating system. What you're referring to as "WASAPI driver" is code that changes the way application communicates with the actual driver. Can you confirm that we are on the same page?

 

[PleasantSounds]

Quote:

 
I'm seriously thinking about creating a step-by-step guide by doing some trial-and-error testing. If I do one, I'll let you know and share it somewhere so others can benefit from my experimentation.

 
Great idea! I see a lot of messages suggesting that people are trying to reinvent the wheel every day. A guide would be very helpful.