Review and Measurements of Audio-gd NFB28.28 DAC and Headphone Amp

[amirm]

Funny thing but a bit off topic: Audiophonics.fr (One of the biggest audio seller in France and the first EU Audio-GD distributor) linked ASR reviews on their Khadas Tone Board and Topping DX3 product pages. But this is probably a bad move, since on the same website, you can also see how horrible AGD products measure...

Audiophonics folks are good people. They have sent me some products to review. And are following up with Audio-gd on this measurements.

 

[Jimster480]

Funny thing but a bit off topic: Audiophonics.fr (One of the biggest audio seller in France and the first EU Audio-GD distributor) linked ASR reviews on their Khadas Tone Board and Topping DX3 product pages. But this is probably a bad move, since on the same website, you can also see how horrible AGD products measure...

Lets see if they take the measurements down later

Audiophonics folks are good people. They have sent me some products to review. And are following up with Audio-gd on this measurements.

Thats actually really great to hear. I hope that AudioGD has a real response for their terrible performance.

 

[VintageFlanker]

Audiophonics folks are good people

@amirm I don't have any doubt about that. I'm a Audiophonics customer for years and ordered many things from them. I was just saying this sounds like a weird plan to link ASR reviews as they are one of the biggest AGD distributors.

 

[jsmiller58]

Do USB Audio Cables Make A Difference?

The short version: only in extreme cases, and not enough to be audible.

“Do USB Audio Cables Make a Difference?”

Yes - to the account balance of the fortunate person selling the “upgrade”

Yes - to the account balance of the unfortunate person falling for the “upgrade”

 

[Audiophonics]

We link some ASR comments because they provide useful and objective information and are mostly reassuring for products that are little known.
We resell many brands and are not affiliated with any of them.
In addition we always had a transparency approach, and if a product is bad, it is not a problem as another will take its place.
We prefer to sell products that will satisfy the customer.

In the case of this Audio-GD measures, it is certain that we were very surprised and disappointed. But the results are so bad that we do not think that all units are similar.

From what I understand, the measured noise level depends greatly on the output level and the gain used, and it seems to me that this test was done at the maximum level of low gain. (that is not a wrong approach)
This kind of Audio-GD product is actually a dual product, consisting of a DAC and a built-in Preamp / Headphone Amplifier, allowing a high output level, up to 16V

It does not totally excuse bad results, but it helps to understand them better.

After several emails with Kingwa, he gave me a video of a NFB28.38 to show me the impact of the output level on performance.
I sent it to Amirm to get his opinion on it, you will find the link below.

In these exchanges with Kingwa, it also emerged that Audio-GD is able to release products with a better THD, even if for him it is not necessarily a guarantee of better sound. This is why it is possible that it will soon offers some products with a special low THD output module.

 

[Veri]

Could it be, another manufacturer that sees the light?

 

[VintageFlanker]

@Audiophonics Good to know! Glad to see you here, by the way!

I knew you being involved in others (French) audio forums, showing your interest about what communities think. Thanks for that.

Ps: C'est en effet rassurant de vous voir vous intéresser (et réagir) à ce qui se dit ici et ailleurs, continuez ainsi !

 

[yue]

audio-gd is not a serious designer at all. Last time I asked them for the measurement data which they claim they have, and in the reply email they told me they can't send it to me. When asked why they told me they once measured it, and they discard the data because it doesn't look good. They are so confident with their design, that they don't even trust objective measurement.

For anyone who believe in objective measurements, you should stay away from audio-gd.

 

[dinglehoser]

Years ago, I bought into the hype and picked up an Audio-gd NFB-11 DAC/amp combo, which as I recall was based on an older ESS chip. It was so subjectively metallic and shrill sounding that I thought something was wrong with my ears. I gave up trying to like it and eventually got rid of it. Almost wish I still had it just to see how close it came to having single digit SINAD ...

 

[BurritoJustice]

If I am reading Audio-GD's website correctly, they are now offering specific APx measurements for the individual serial number products. Crucially, they also state that if you measure worse results using proper equipment then they will consider it faulty for the sake of the warranty.

If it got large different result by the professional instrument test, you may consider it had fault inside and ask the warranty

This is clearly a response to this review, they also state:

NFB-28 is a discrete and non feedback design, its diagram may not look as good as to the deep negative feedback design.

I wonder if anyone is game to test this policy. I could see myself being so inclined if they offered it for the R2R combo designs, so I can experience the total other end of the objective spectrum from my ADI-2 Pro Fs with the added bonus of testing the policy and identifying whether the extreme difference seen above is universal.

 

[Veri]

@BurritoJustice great idea/inititive

I don't think this policy will work on their R2R too though.

 

[Jkdjedi]

"Nothing really broken here other than higher noise floor and sidebands that get somewhat too high. Fortunately audibility of all of this is very low to non-existent so not a problem." Does this mean all these tests are inaudible? I will admit listening to some tracks demonstrated some distortion from usb input and it's been almost entirely gone using the spidif input, sound right to you guys? (11.28)

 

[amirm]

"Nothing really broken here other than higher noise floor and sidebands that get somewhat too high. Fortunately audibility of all of this is very low to non-existent so not a problem." Does this mean all these tests are inaudible? I will admit listening to some tracks demonstrated some distortion from usb input and it's been almost entirely gone using the spidif input, sound right to you guys? (11.28)

That is just for jitter test. Other tests show more serious issues.

 

[jsheard]

What qualifies as a "professional instrument" for that policy? If the customer is expected to use a $20,000 AP analyser to prove their unit isn't up to spec then the number of people who could possibly take advantage of that policy is probably in the low single digits...

 

[graz_lag]

audio-gd is not a serious designer at all. Last time I asked them for the measurement data which they claim they have, and in the reply email they told me they can't send it to me. When asked why they told me they once measured it, and they discard the data because it doesn't look good. They are so confident with their design, that they don't even trust objective measurement.

For anyone who believe in objective measurements, you should stay away from audio-gd.

AFAIMC - Back in 2015 ... I appreciate who feels he can translate the below feedback into @amirm graphs ...

Dear .....,
The NFB11 sound most neutral, emphasize detail, dynamic and speed. Bass is tight and impact.
The NFB15 sound is a bit on warmer and smoother side in compare, the bass is rich but not very tight.
It is no matter with Windows and most Linux.
Kingwa

 

[Jkdjedi]

We link some ASR comments because they provide useful and objective information and are mostly reassuring for products that are little known.
We resell many brands and are not affiliated with any of them.
In addition we always had a transparency approach, and if a product is bad, it is not a problem as another will take its place.
We prefer to sell products that will satisfy the customer.

In the case of this Audio-GD measures, it is certain that we were very surprised and disappointed. But the results are so bad that we do not think that all units are similar.

From what I understand, the measured noise level depends greatly on the output level and the gain used, and it seems to me that this test was done at the maximum level of low gain. (that is not a wrong approach)
This kind of Audio-GD product is actually a dual product, consisting of a DAC and a built-in Preamp / Headphone Amplifier, allowing a high output level, up to 16V

It does not totally excuse bad results, but it helps to understand them better.

After several emails with Kingwa, he gave me a video of a NFB28.38 to show me the impact of the output level on performance.
I sent it to Amirm to get his opinion on it, you will find the link below.

In these exchanges with Kingwa, it also emerged that Audio-GD is able to release products with a better THD, even if for him it is not necessarily a guarantee of better sound. This is why it is possible that it will soon offers some products with a special low THD output module.

And he tested from the coaxial input, not the usb input, does that make a difference? (to me it appears that it does)

 

[Jimster480]

When I emailed back and forth with him last year while inquiring about a unit... it was very obvious to me that he had no idea what he was doing.
When I started asking him about the difference in the units and their reason for difference in price and the performance; he tried to claim he doesn't understand english well.
So I had one of my chinese associates write him the entire message in his native language, the answer that he replied in chinese wasn't really any better.
Trying to say that you have to "hear the difference" vs the "claimed specs" and prices.

 

[BurntheHeadPhoneKid]

Devastating.

Truly

 

[Veri]

Anyone else notice the "AS-1 ultra low distortion" product? Is this new?

 

[bunkbail]

Anyone else notice the "AS-1 ultra low distortion" product? Is this new?

Haven't seen that one before. Audio-gd is following Schiit footsteps??