OP
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- #21
Here is the dynamic range:
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Review and Measurements of NAD 7050 Streaming Amp
- Thread starter amirm
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I'm sure it's about the pink panther you're using, they simply don't have it on their desk while doing the measurements, so that would be a huge advantage for your measurements. You should probably open an online store with these "audio totems"; a fair starting price could be 1000 USD per item.
BTW, I see the high freq. noise on their graph too, especially on 8 Ohms measurements.
OP
- Thread Starter
- #24
I just packed it to ship tomorrow.....
miero
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OK, no problem. Do you have another NAD product in the queue? D3020 would be a nice cheaper alternative, but it was already measured by Stereophile -- https://www.stereophile.com/content/nad-d-3020-integrated-amplifier-measurements
maty
Major Contributor
[Polish] https://audio.com.pl/testy/stereo/wzmacniacze-stereo/2608-nad-d7050
to English: https://translate.google.com/translate?sl=pl&tl=en&u=https://audio.com.pl/testy/stereo/wzmacniacze-stereo/2608-nad-d7050
to English: https://translate.google.com/translate?sl=pl&tl=en&u=https://audio.com.pl/testy/stereo/wzmacniacze-stereo/2608-nad-d7050
- Rated power (1% THD + N, 1 kHz) [W] 8 Ω, 2x 33
- Rated power (1% THD + N, 1 kHz) [W] 4 Ω, 2x 64
- Sensitivity (for maximum power) [V] 1x -
- Signal-to-noise ratio (A-weighted filter, with reference to 1W) [dB] 71
- Dynamics [dB] 86
- Damping factor (relative to 4 Ω) 69
This is a review and detailed measurements of the NAD 7050 integrated DAC, amplifier and streaming playback. It is on kind loan from a member. It appears the product was announced in 2014 and since discontinued as I can't find it on sale anywhere. The cost was USD $999 from what I can gather.
The unit can be used both horizontally and vertically. A rotational sensor changes the display orientation conveniently. Here is its upright position which I consider better for sound since the electrons can naturally free fall into the speaker terminals:
The outside has what appears to be some sort of rubber glued to it. It is soft to touch but picks up dirt very easily and is impossible to clean due to sticky nature of it.
The large knobs imply great feel which they don't have. They wobble as you rotate them. The larger knob is the volume control which had an odd delay in updating the display as you rotated it. Overall, a good effort has been made to create an unusual design but didn't quite get there in feel and functionality.
The back panel shows off the inputs and speaker output:
For my testing, I focused on USB input as I suspect that is the most common interface for consumers. Alas, the USB interface is class one so only goes up to 96 kHz. To get the advertised 192 kHz you need to use the other inputs. I downloaded the NAD drivers which nicely gave me ASIO interface for testing.
There is an app to control it and I downloaded it from Android play store. It is a simple remote control but allowed me to change the audio-out to be full range so I could use it for DAC testing. Otherwise it is filtered for subwoofer out. Despite its simplicity the app crashed on me once.
There is no analog input so I had do all of my testing with USB digital interface.
As expected from a brand name company, the NAD 7050 comes with full set of safety and emissions regulatory certifications.
The amplification in NAD 7050 apparently is a scaled down version of what is in NAD M2. Here is what NAD says about it:
View attachment 23134
My read is that it is a power DAC similar to Lyngdorf TDAI-3400 I reviewed recently. Measurements will confirm if so.
DAC Measurements
As usual, where possible I try to isolate the performance of the subsystems, in this case the DAC. Here is our dashboard view using USB input/Line Out. I hope you are sitting down if you owan the 7050 and use it as a DAC:
View attachment 23135
What the heck is going on here? Even at 0 dB the unit doesn't get to 2 volts yet it severely clips resulting all of those harmonic distortions. Dialing down to -2 dBFS improved performance but just to 83 dB. By then the output voltage was even lower, making it not so useful as a DAC anyway. My thinking is that this is a split off output from the power amplifier as opposed to a traditional DAC output. I guess for the assumed subwoofer duty it may be OK.
Naturally, with the SINAD as measured falls at the bottom of the graph of DACs tested:
View attachment 23138
After the first bad impression, the 7050 almost nails the rest of the measurements such as linearity:
View attachment 23136
And jitter:
View attachment 23137
Since USB doesn't support 192 kHz, I had to run a different multi-tone test at 44.1 kHz:
View attachment 23140
Amplifier Measurements
As usual, the dashboard view is at 5 watts of power into 4 ohm:
View attachment 23139
As power amplifier measurements go, this is not too bad actually and almost matches the vaguely stated 90 dB spec by NAD.
Power versus distortion+noise is also pretty decent:
View attachment 23141
The downward part of the curve is always dominate by noise as the output level is low. Here, that part of the curve is flatter than I am used to seeing which is good as far as level of noise. Likewise, distortion is kept under complete control until onset of sudden and massive clipping at 54 watts. This too is good (sans the clipping). Stated rating is 50 watts at 4 ohm and we beating that a bit which is nice. Then again, 50 watts is not that much power in grand scheme of things.
THD+N versus frequency using my default 45 kHz bandwidth shows pretty awful results (in red):
View attachment 23142
Suspecting ultrasonic noise at play, I re-ran the test with 22.4 kHz (as with the dashboard) in blue which shows that effect quite conclusively. One channel is worse than the other though which is strange. Note that the drop above a few Khz is due to bandwidth of the test being too low to capture all the harmonics (and hence the reason I like to use 45 kHz bandwidth normally).
Broadband FFT shows of 1 kHz tone shows us what is going on:
View attachment 23143
This is without my Audio Precision high-frequency filter (AUX-0040). All the other tests used that filter.
On the extreme left we see our 1 kHz tone as a spike rising to 0 dB or so. We have a single and large spike at 850 kHz. That seems to indicate to me that 850 kHz may be the switching frequency. Given its high frequency, the power DAC is running likely with as a single bit converter which would create a lot of quantization noise. Noise shaping is used to push that above 30 kHz or so with the peak at about 80 kHz. This is the drawback of power DACs as we have seen in the Lyngdorf and SONOS Amp versus class D amplification which doesn't need noise shaping. You can see the effect of high frequency noise in the thickened sine wave of the same signal in the inset.
Conclusions
Usually, by the time I get to the end of testing, I have a good idea of if I like or don't like a device. Here, I am not quite sure. Let's agree that no one should be using the NAD 7050 as a DAC with external amplification as NAD suggests in the manual. You will be listening to a heap of distortion products with anemic output to boot.
The amplifier seems to have some good tricks under its sleeves with lower than normal noise and very controlled distortion until a very hard limit. My issue there is the 50 watt rating for a $1000 device. That is just not enough power for a product in this category.
Seeing how the NAD 7050 is discontinued, maybe it doesn't need my recommendation or lack thereof anyway. So I will leave it at that.
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I think you should remeasure this device in a horizontal position as free fall of the electrons must have caused such poor SINAD figure due to their collision with terminals.
I have been using one of these D3020s in my study system for a few years connected by USB to my work computer and to old Proac EBS speakers. The room is 12’ x 15’ and the display shows around -15dB to -20dB fwiw.
graz_lag
Major Contributor
It looks NAD had been losing the right way of doing things since the integration within the Lenbrook Group (PSB Speakers) ...
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I think you should remeasure this device in a horizontal position as free fall of the electrons must have caused such poor SINAD figure due to their collision with terminals.
Your joke is actually the kind of nonsense one is likely to encounter at a "high end" store. Years ago (true story) my dealer sold me an Acoustat system (if anyone remembers them). MOSFET amp and preamp, plus tall electrostatic speakers. It was pretty good value, in the scheme of things. The idea was that FETs were supposed to sound 'tubelike,' and tubes were authentic 'high end'. The store also sold a line of tube gear; I think it was Conrad Johnson. Anyhow, the salesman-owner told me how he was told by the tube brand's rep that a competing design (Counterpoint, another tube brand sold back in the day), using horizontal tube sockets (in order to sort of mimic the Mark Levinson preamp look), might not be as good as vertical tube sockets, since the tube filaments could sag the wrong way, causing electrons to introduce time smear. I swear the guy was serious. In the early days of 'high end' we were all mostly idiots and fools. Some still drink the kool aid.
LOOL
When I see how many folks believe that vaccines are dangerous and that Earth is flat believeing in HiFi "high end" nonsense seems very benign to me.
MetalheadRich
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I would have liked to see the headphone out tested, but not a huge deal I guess.
MetalheadRich
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why? if it clips the same way, that should be easy enough to avoid.
invaderzim
Senior Member
Because people don't know any better; when it comes to audio the only way to know that there are higher quality choices is to hear better examples. As always I wonder if their engineers are pleased with the results or angry that they weren't allowed to improve it. Were they kicking and fighting all the way through or did they go home thinking "that is awesome!"
That being said as confucius_zero points out it is in the top 4 of the amps tested on here.
I've seen rave reviews of the STA200 which tests way worse and doesn't have the appearance that looks great in an office or on a desk like this one. And this is a one item does most everything solution too.
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I'm not so sure the amplifier is all that hot. Yes, the 1kHz performance is pretty good, but I'm going to go out on a limb here and guess that the IM distortion would have been pretty bad, if it had been tested fully. I would continue to urge a frequency sweep at full power, or at least a 10kHz or 20kHz THD test to really put an amp through its paces and test linearity.
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Back in the 'stereo' day you had at least 3 mainstream magazines that routinely did (at least) cursory measurements that could be used to validate published specs. Those magazines are long gone. Specs are often not very well published, anymore, either. In its later years, Audio Critic had David Rich take apart amps and CD players, and critique them from an engineering standpoint, but those days are gone, too. Now, sadly, Rich is consigned to occasionally reviewing phono cartridges for a mostly worthless Webzine. And those are buried deep in within cyber clicks, because evidently the publisher doesn't want to publicize his findings. Oh yeah, he did a primer on buying and refurbishing open reel tape decks, a while ago. How the mighty have fallen.
I don't know, but my guess is that a company like NAD relies on marketers to tell them what they can likely sell, and at what price point. Then in-house or contract designers are given a parts bin to work with, and told to come up with something. The final product is sent to one of the subjectivist sites, and if there are enough advertising dollars present, it is given a review. The more expensive the product is, the higher it is rated. If the reviewer likes it, for whatever reason, he just keeps it, or maybe even 'buys' it for a huge discount. There was a recent 'scandal' uncovered at one of the last big subjectivist magazines: the reviewer admitted that he misplaced a multi-thousand dollar phono cartridge for a year or so, never wrote a review, but the manufacturer (Ortofon) never asked for it back. My guess was that they were too afraid to alienate the reviewer. The reviewer later found it, wrote up a quick review praising it, then 'bought' it from Ortofon for an undisclosed dollar amount. LOL
The unsuspecting consumer has nothing else to go by, other than perhaps what a brick and mortar commissioned salesman might tell him. Or, if he doesn't have audio salon dollars to spend, he goes on the Crutchfield site, calls up an 'advisor' and makes his order based on price. And that is that.
invaderzim
Senior Member
It would be really nice if they were required to say in their review if, in the end, they were gifted the item or for what percentage off they bought it or if they sent it back.
More and more retail sites are listing under people's reviews if they received something in exchange for the review but the official publications still breeze past that.
But I guess, in reality, even if they have to send the review sample back they will want more review samples sent to them as well as advertising dollars from the companies and glowing reviews would do a lot more to see that happen.
That sounds like a Dilbert cartoon but sadly I'm sure it is the truth. The engineers are told "Here's the packaging, here's the price, here's the time frame, make it"
I remember the first amp and speakers I bought; I spent hours at the shop listening to what they had and talking to the salesman. I'm sure he got sick of me but those were our main system for two decades and I still use them both in another room nearly 30 years later. Now it is harder and harder to find a place to listen to equipment so you buy it and have to hope it was the best in that price range.
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I had a 7050 for a while, and the one great feature it had that I hadn't seen anywhere else was that the 'line out' could be repurposed as a *stereo* low-passed woofer / subwoofer output. Mono sub/lfe output is obviously common, but the stereo output allowed crossing over mini-monitors to stereo woofers at 200Hz. Actually worked well, but sold it when I changed out my main speakers and no longer needed the 2-way functionality.
Obviously subjective, but I thought it sounded decent enough when fed strictly from digital sources.
Obviously subjective, but I thought it sounded decent enough when fed strictly from digital sources.
graz_lag
Major Contributor
After Mr. Gordon Holt sold Stereophile magazine at the end of the Seventies, the policy did a swift 180° turn from "No Advertising" to only reviewing products that were advertised in the magazine - and had a minimum of six dealers, making for a slick little Catch-22 for new manufacturers trying to break into the market. You either had deep corporate pockets and entered the market with a big splash, or could forget about any reviews in the magazine that now saw itself as the industry's gatekeeper.
In a few years, things reached the point where high-end audio was no longer about sound, but perceived status, with high-profile reviewers passing out awards to the "inner circle" of manufacturers. Dealers had little choice but go along and get along; customers came in to the store clutching a dog-eared copy of the magazine, and by golly, they wanted that "Component of the Year" right now. At a discount. Especially if the review said it was much better than last month's favorite.
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