[Alexdad54]

As Nick replied in the other thread, the Audio-GD DI will definitely work with the ALix box, he was key in helping me set up an Alix and DI together.
FWIW, I am using it with an MHDT Havana NOS DAC and it is superb but when I tried it with an Eastern Electric Minimax DAC (with the ES 9018 Sabre chip) I had frequent recurring drop-outs. I have read (but am far from an expert on the subject) that this may be due the Sabre chip in the Minimax having difficulty locking on properly to the signal from the DI.

[rklein]

For those of you who are using an NFB-2 or NFB-3, are you using the USB on the DAC or are you using an USB/SPDIF converter?  What are your impressions of the sound quality using the USB on the DAC as opposed to using the DAC with a converter.

I have emailed Kingwa and asked the question of whether the USB implementation on the NFB-2/3 is the same as the USB implementation on the DI.  If it is, I probably will save myself some dollars and just order the NFB-2 without the DI.

I already have a John Kenny Modified HiFace MKII.  The problem is that the M2Tech drivers are not compatible with Linnux(Alix), hence my interest in the Audio G-D DI

Randy

[JohnR]

John got any lowdown for us on the NFB-12 now that you've had it a little while???

I feel that maybe it's time for an update on this one. I've tried every which way I can, and I simply cannot get good sound from the NFB-12. I know it's a relatively cheap unit, and I hate to say it as Audio-GD has a great reputation in general and this should be a bargain product, but I'm happy to just get rid of it at this point. Since I bought mine, Audio-GD have come out with a new version with switches to set filter parameters but honestly I would be surprised if they make a fundamental difference. The one I have just tends to sound "sucked out" in the midrange, there's something not right with it. I'm sorry but I can't stand listening to it for any length of time.

Bearing in mind that I am in Australia and this unit is beefy (for a headphone amp), I'd be happy to give it away to anyone here for the price of po$tage and a promise to post a fair evaluation of your thoughts here on AC, in case i really have gotten it wrong. Just send me a PM with how you plan to evaluate it and I'll take the fairest offer.

Thanks

[JohnR]

This is now taken. After the PM I realized that I of course got a unit wired for the correct wall voltage. I took it apart, no luck so I googled:

  http://www.head-fi.org/t/524263/audio-gd-nfb-12/1905#post_8272336

Thankx head-fi The jumpers were hidden under a piece of tape on the board... (?!) So I'll try converting it over tomorrow - or Saturday if that doesn't happen - and confirm that it still works.

Jeez, I can't believe how well this thing is built. If I had a ready use for the power supplies in it, it would almost be worth the price just for them. Oh well...

[Letitroll98]

I feel that maybe it's time for an update on this one. I've tried every which way I can, and I simply cannot get good sound from the NFB-12. I know it's a relatively cheap unit, and I hate to say it as Audio-GD has a great reputation in general and this should be a bargain product, but I'm happy to just get rid of it at this point. Since I bought mine, Audio-GD have come out with a new version with switches to set filter parameters but honestly I would be surprised if they make a fundamental difference. The one I have just tends to sound "sucked out" in the midrange, there's something not right with it. I'm sorry but I can't stand listening to it for any length of time.

I read as many pages as I could get thru in one sitting of the discussion over on Head-Fi when the unit first came out.  There was a big discrepancy between those who feel as you do and those who thought it was just fine for the price.  The general consensus of the nay sayers is that the DAC was not suited to run 44khz with the filters selected by the designer and if you either upsampled to 196 before feeding the signal to the DAC (using Foobar or some other program) or pulled pin 22 on the DAC to make it run 96khz max it fixed the problem and the unit sounds just fine.  Kingwa, the designer, and the folks who liked it said the right filter was chosen and it sounds just fine like that.  Obviously since the newer model has jumpers to change the filter characteristics, the nay sayers won over the designer, or he just caved to the market demands.     

[Sparky14]

Man...you guys sure expect a lot for a $200 pre-amp, dac, and headphone amp. 

I have the NFB-11, which was the initial effort in the NFB-12 vein but had the ESS9018 Sabre DAC. I have tested this thing against $1000+ DACs and much more expensive stand alone amps. While I have been itching to buy something "better", I have never found a unit that substantially improves upon the NFB-11. I am pissed now because I once had two of them, sold one figuring I'd get something better for home, and now I want it back.

As for the filters....Kingwa had implemented switchable filters long before the NFB-12, but in more expensive units. The switchable filters have made their way down to the less expensive units such as the NFB-12 and NFB-15.

[Letitroll98]

Hey Sparky, maybe you can answer something for me.  Do all NFB-12 (11) units have the jumpers to adjust the digital filters, was it a running change in the model, or is that only a feature of the NFB 12.1?  As typical with these manufactures, very little info is available on the website. 

As far as being tough, I'm just repeating the synopsis of the threads on Head-Fi, I've never heard the unit.  Please dear sir, don't shoot the messenger.  I'd be ecstatic if it sounds great.

[Sparky14]

Hey Sparky, maybe you can answer something for me.  Do all NFB-12 (11) units have the jumpers to adjust the digital filters, was it a running change in the model, or is that only a feature of the NFB 12.1?  As typical with these manufactures, very little info is available on the website. 

As far as being tough, I'm just repeating the synopsis of the threads on Head-Fi, I've never heard the unit.  Please dear sir, don't shoot the messenger.  I'd be ecstatic if it sounds great.

My NFB-11 does not have any switchable filter jumpers. I don't know if the initial NFB-12 did, I suspect not as I remember it being identical except for the DAC chip. They were in for the 12.1 though.

Not shooting the messenger, just pointing out that the NFB-11/12 offer a LOT for $200ish.

[JohnR]

No filter jumpers on this one. Kingwa told me the equivalent settings, which I'll dig up when I send it to Letitrol.

[Letitroll98]

Arrived tonight in good order, only played for an hour and at low volume.  So far nothing to complain about and a lot of possibility.  I won't comment much yet, mostly so I won't paint myself into a corner either in print here or in my mind subjectively. 

[JohnR]

The equivalent filter settings: OS: 2, Filter: 3

[Letitroll98]

The equivalent filter settings: OS: 2, Filter: 3

2X oversampling , Linear phase 'brickwall' filter.  Hmmm.  Not what I would have chosen.  Much more problematic sound at normal volumes this morning.  Still experimenting a lot, in other words no love at first blush.

[JohnR]

2X oversampling , Linear phase 'brickwall' filter.  Hmmm.  Not what I would have chosen.  Much more problematic sound at normal volumes this morning.  Still experimenting a lot, in other words no love at first blush.

Any update?

[Letitroll98]

Yes I do.  I was waiting to complete some headphone evaluation, which I mentioned to you would be after it was in my main system.  My evaluation as a headphone amp won't be a lot different than yours, but as a stand alone DAC it has merit.  I'm away at my father's memorial typing on a phone,  so I'll need to hold off until I get back to give a full review.  Should be home late Tuesday.

[Letitroll98]

JohnR was very kind to offer to send his Audio GD NFB 12 to me to give it another ear as he couldn’t make it sound right, as I interpret a midrange suckout making it unlistenable.  A nice unit on paper with dual Wolfson WM8741 chips  The deal was I was to post my impressions of it online.  He’s been waiting some time for this to occur, and I can tell his patience is wearing thin.  Well this has been the hardest component to nail down that I’ve ever experienced, it keeps changing like a chameleon.  I think I finally have a handle on the changes.

The unit arrived at my door when I came home somewhat late and I installed it into my main system playing low level late night listening and it sounded fine.  The next morning I rushed to play it at high sound levels it was pretty much unlistenable.  Rather than a sucked out midrange, I had harshness or glare in the mid-treble and up, note at this time that I had immediately switched it to fixed output without listening to the variable output much past that first night as my current DAC sounds much better that way.  I have two pre-amps that have both active and passive options, so I tried it both ways, using both high level and low level outputs, and while the sound did change a bit, it didn't get better in any significant way.

So in an effort to fix something, anything, asap, I thought I'd try it direct into the amp and cut out my preamp.  Of course to implement this I switched to the variable outputs.  Well this sounded a lot better.  A large portion of the glare was gone and I could actually listen to music.  I played with power cords and interconnects and although I could hear their effect, it didn't change the basic sound of the DAC.  Then I wondered if it was the variable vs fixed output rather than my preamp, so the preamp goes back in the circuit.  At this point I'm assuming there is a difference between variable and fixed outputs because although there is the inevitable slight haze of another component, the DAC sounded essentially the same as direct to the amp.  Then later I went back to fixed output and it had lost most of the troublesome harshness and sounded as good as the variable outputs. (??)  Curious.  As mentioned the DAC has high and low level output settings and these stayed consistent through all listening conditions, high level was more direct and dynamic, low level recessed and darker, my comments will be on the high level outputs as I preferred that setting. 

So about now you’re asking what is the sound of this DAC?  At it’s best pretty good for a $200 DAC.  Great bass impact, nice detail, good soundstage with a very nice separation of instruments, but there’s a persistent hardness or glare to the mid to upper treble that never goes away completely.  Not a dealbreaker for sure at $200, but always noticeable.  The manufacturer states this is the softer, more rolled off model, while not tipped up in the treble, compared to my regular TC 7510 using the venerable Burr-Brown PCM1716 it didn’t sound reticent at all.  Although I’d be content spending $200 for the unit, I’m not sure I could make it a keeper.  I like listening to the unit, but I constantly have this feeling of wanting more.

The chameleon sound?  It turns out you need to warm up this thing for a ½ hour or so every time you listen to it.  Not just leave it turned on, it has to play music for a bit before it settles down.  I still don’t believe this to be possible, but I’ve spent weeks with the NFB 12 and that’s what I’ve found.  Please feel free to criticize and critic this conclusion as I’m fine with being proven wrong here.

Then I sent a note to John about my findings, well, I replied to his insistent requests for an update, and he said, “Strange, I had never considered using it as a stand alone DAC.”  So I pulled out my Sennheiser HD 203 headphones to give it a listen (don’t laugh, they’re perfectly fine for my Ipod and a very good budget set of phones).  Straight out of the NFB 12 using the SPDIF inputs from my transport, finally I heard what John was talking about.  A hollow suckout through the midrange making the whole presentation unnatural.  I switched to the headphone output of the preamp and this disappeared.  Must definitely be a fault in the headphone amp.  Then I moved the unit to the computer to try out the USB interface, and a seachange in sound quality.  Using some FLAC and WAV 44khz samples that I had used on the big rig the sound was sweet and open, perfectly toned, with only the slightest touch of the hard glare I heard at the units worst days.  I could be very happy with the Audio GD NFB 12 as a computer source for a very long time.  Why the change?  I can only assume the USB interface softens the sound, dropping off a bit of detail perhaps, making the unit sound more musical.  Why is the midrange suckout gone?  Not a clue, but it is.

Thanks again to JohnR for his generosity, I hope I haven’t peeved him too much with the long delay.  And a bonus to those who waded through this review, anyone who wants to listen to the unit, send me a PM and I’ll get it out to you for a trial.  I’ll continue playing with it for a bit and post any changes, depending on how many are interested I'll then send it around for a listening tour.

[tomytoons]

The chameleon sound?  It turns out you need to warm up this thing for a ½ hour or so every time you listen to it.  Not just leave it turned on, it has to play music for a bit before it settles down.  I still don’t believe this to be possible, but I’ve spent weeks with the NFB 12 and that’s what I’ve found.  Please feel free to criticize and critic this conclusion as I’m fine with being proven wrong here.

You are not wrong. I had a gd NFB 2 (used, non switchable filters) and it did the same thing exactly. You can hear it change after 30 minutes of play not just being on.
I thought I was nuts but others have mentioned this too with this particular NFB 2.

Sold it! The Wolfson chip is too laid back for me I was just not moved by it.

[JohnR]

What, me insistent? 

Thanks Letitrol for taking the time, you've given it a much more thorough and fair evaluation than I did. It sounds like chameleon is a good word for it.

[eclein]

I thought these units were the super hot ones last year? Am I thinking of a different model?

[wushuliu]

I thought these units were the super hot ones last year? Am I thinking of a different model?

There have been a lot of changes in the lineup over the last 18mos. I think this version is a little older.

Sorry you struck out on the NFB-12 John! 

[Letitroll98]

You are not wrong. I had a gd NFB 2 (used, non switchable filters) and it did the same thing exactly. You can hear it change after 30 minutes of play not just being on.
I thought I was nuts but others have mentioned this too with this particular NFB 2.

Sold it! The Wolfson chip is too laid back for me I was just not moved by it.

Thanks for that tommy, nice to hear from at least one person that I'm not crazy.  Well you didn't say not crazy exactly, just not wrong, somewhat different perhaps...

The only thing I could think of is the SMD's.  Perhaps for some reason they need current through them?  But the NFB 2 (and current 2.2) have discrete components.  So we'd have to look elsewhere.  John Darko also said 1/2 warm up for the NFB 2.   

I can hear what you're saying about the Wolfson chips, lots more low end energy, but I prefer that presentation.  Although fairly dynamic, I can see how some would want a more dramatic presentation.  Different horses.  Nice to have so many inexpensive chips to choose from.

What, me insistent? 

Thanks Letitrol for taking the time, you've given it a much more thorough and fair evaluation than I did. It sounds like chameleon is a good word for it.

No John, thank you.  I'm having a blast with this thing, much more fun than something that's easy to figure out.  Listening to some WAV files now and it sounds excellent.  (Shadowfax, Too Far To Whisper)  I'm pretty sure it's a little less incisive through the USB interface, details softened, the edge taken off, which is just what is needed in this unit.  It has a nice sound in the big rig, but there's a cheapness to the upper ranges when played there, which can be expected for the price, but it's a letdown with he rest of the performance so nice.  I'd like to hear the next level up in the Audio GD line without the SMD's like the 2.2 (without headphone amp tho), or maybe a tube buffer with this unit. 

I thought these units were the super hot ones last year? Am I thinking of a different model?

There have been a lot of changes in the lineup over the last 18mos. I think this version is a little older.

Sorry you struck out on the NFB-12 John! 

Yes, this is the earliest model without any internal jumpers to change the filters or sampling rate.  As I understand, the rest of the unit is unchanged.  I would expect subtle changes with those adjustments, but subtle changes might be just exactly what this unit needs.  The latest 12.1 model with the external switches to change filter and rate for $215 could be a pretty good deal.