Audio-GD NFB-12 - Page 144

They all look the same, is the only difference in the treble?

No. Some of them even affect the bass for some reason. I know it's weird but the 8x minimum phase apodising filter has less bass than some of the other ones

 

Thinking to buy this that it can be used to control volume as well

 

My setup is

 

PC->Audio-gd->Active crossover->Amp->Speaker

 

 

 

i want to control volume from the DAC as there is no other place i can contrl the volume output PC is a MPD which send bits perfect to the DAC....

 

This can act as a preamp with volume control am i right for USB and coaxial input....

 

 

V

Yeah it works as a pre-amp, the volume out of the RCA can be controlled using the fake Alps pot. Funny thing is, since the RCA are the same thing as the headphone out, the High and Low gain mode also affects the volume out of the RCA... which is just silly because the signal is already way too high on low gain with the fixed out.

Thanks for this...has anyone have any idea if i connected my RCA output from my Classe preamp for HT purpose and i feed into Audio-gd using RCA to Coaxial wire  will it be able to swtich between coaxial and USB which is coming from PC....

 

 

V

By RCA you mean digital audio over coaxial? If that's the case, then yes. Though the NFB-12 will only be able to decode stereo PCM signal. It's unable to decode surround or any other digital encoding. Most DVDs these days are encoded in AC-3 or similar. Some have a PCM stereo track, but they are getting rarer. If your preamp supports it, it may be able to re-encode the input signal into stereo PCM, though I've no experience with pre-amps so I'm just guessing here.

The complaints about the heat of the NFB-12 seem to be legitimate. I left mine on for about 2 days (listening to music while I'm sleeping, listening to it while I'm awake), and suddenly it powered off. Touching the top of the unit was nuclear, too hot to touch.

I think it has a bad power supply, nothing looks burnt or blown inside. It's safe to say that it was killed by heat. Room temp at death was a fairly chilly 8'c / 46'f as well..
Edited by Elanzer - 12/4/12 at 10:26pm

Why not just turn it off when you're not using it...? It's a flick of a switch. I doubt you listened to it 48 hours straight with no breaks.

The problem is that I'm using it while I sleep, as in I'm listening to music then fall asleep with it on. Then immediately when I'm up in the morning, I'm using it again, so it doesn't get a period to rest.

No. Your headphones are not on your head 48 hours straight. If that's the case, you have bigger problems than an overheating headphone amp.

I'm not using my headphones on while I'm sleeping. I'm using it as a DAC to my powered speakers which plays music that I fall asleep to, then when I get up I turn off the speakers and use the headphone output.

So you never leave your home? And you never turn off your music? How do you get food? When is the last time you saw the sun?

I didn't leave my home for a period of 2 days, no.

I listen to music or otherwise use audio output at all times when I'm at home, yes.

How do I get food? From my fridge. Why would I turn off the amp going to the fridge? I only go grocery shopping once every couple weeks.

I saw the sun this morning.

 

That's interesting. And it still is not working, even after cool down?

 

By powered off, you mean that nothing works anymore? The LED doesn't light up, it's not recognized as a DAC trough USB, no audio out.... Since it has a different power supply for each of these features, if nothing works you probably burned the transformer itself.

 

This thing was not designed to pass safety and performances tests like the ones performed by UL. It's not designed to be used non-stop for days. I'm not really surprised it died.

Well, it seems to be a blown power supply because that's where the extreme temperatures were originating from.

I opened it up to check out the internals and let it cool off for awhile. It turns on, but with it set to High gain it shuts off the power LED and the output has buzzing in it, then after about 5 minutes it loses power. With it set to Low gain, it fares a bit better: the power LED stays on and it does not buzz, but eventually gives out after about 10 minutes and shuts off.

I guess when I get it back from repair I'll set it ontop of my PC, that way the 140mm exhaust fan ontop can provide some active cooling for the NFB-12. Having it on a desk with a clear surrounding in almost freezing room temp isn't enough for 2 days of operation apparently.
Edited by Elanzer - 12/5/12 at 12:34am