Measurement and Review of Emotiva DC-1 DAC

[NorthSky]

Thx

"The Stealth DC-1 uses dual independent AD1955 differential D/A converters, each operated in their highest quality internal differential monaural mode, for the lowest possible noise and distortion, followed by professional-grade LM4562 op-amps in the analog section for maximum fidelity. An advanced switchable asynchronous sample rate converter (ASRC) re-clocks the data at the same sample rate as the incoming signal, to dramatically reduce jitter."

 

[Mad_Economist]

I seem to recall the Emotiva has a really hefty headphone amp. Might be worth looking at the output of that.

Memory serving it is a BUF634 or LME49600 nested buffer with an LM4562 or LME49710, analogous to Benchmark DAC1, Lynx Hilo, "The Wire", etc. Should perform quite well on paper, I look forward to seeing how it performs in reality.

 

[DonH56]

Amir, you need to hire help, by the time you get time to review they've upgraded (DX7 -> DX7s and now DC-1 to DC-2). But I certainly love the reviews!

I hate the look and feel of the new Emotiva website FWIWFM.

 

[Sal1950]

and now DC-1 to DC-2

Looks like the requests for full size headphone jacks was ignored and now there's only one.
Since I have no interest in DSD or streaming WiFi nothing here for me. My old DC-1 will most likely hang with me till it lets the smoke out.
I'll still believe the March release date when I see it, heard that before.
https://www.avnirvana.com/threads/e...dc-2-dac-and-confirms-rmc-1-launch-date.2039/

 

[SpeedyRodent]

Looks like the requests for full size headphone jacks was ignored and now there's only one.
Since I have no interest in DSD or streaming WiFi nothing here for me. My old DC-1 will most likely hang with me till it lets the smoke out.
I'll still believe the March release date when I see it, heard that before.
https://www.avnirvana.com/threads/e...dc-2-dac-and-confirms-rmc-1-launch-date.2039/
View attachment 10312

The DC-2 is also more expensive. Edit: $699 didn't read the link. I also read of rumors of a balanced headphone amp is also coming to match the DC-2.

 

[sssn]

What's the output impedance?

 

[amirm]

What's the output impedance?

To be measured soon when I go after the headphone amp.

 

[amirm]

Here are a few headphone measurements.

First up is the output impedance at 1 Khz:

As you see it is an excellent 0.92 ohms! So definitely a stout output that can drive any impedance headphone without changing its frequency response.

Next is the channel balance as level is reduced on the front panel from 0 db to -50 db. Load is 300 ohms (as is the case for the rest of the measurements):

The measurement is stereo and we want the two channels to land on top of each other (so looks like one color). That happens until we get down to -40 db where slight deviation appears and becomes about 1 dB at -50 db level. I don't have my IEMs in the lab but I am assuming that is a pretty low level and channel imbalance is not an issue.

You can also eyeball the accuracy of the volume level db scale relative to measured one. It looks pretty good I think.

Zoomed in frequency response shows just a bit more roll off than RCA jacks:

Not a concern though.

Next I thought I run my DAC linearity test to see what the headphone output does to it:

Looks like we lose about 2 bits. And the extreme low level response is pretty bad, shooting way up. Likely noise dominated.

Finally here is the distortion products of a 1 Khz tone that has been filtered out. Not sure it is very useful with 300 ohm load but here it is anyway:

Hopefully I get more reference data in the future with these measurements to make them more useful.

For now, I say the verdict is quite good for the headphone output of the Emotiva DC-1.

 

[SpeedyRodent]

Here are a few headphone measurements.

First up is the output impedance at 1 Khz:

View attachment 10346

As you see it is an excellent 0.92 ohms! So definitely a stout output that can drive any impedance headphone without changing its frequency response.

Just a friendly question. What is the reasoning for measuring output impedance at 1Khz? I don't have the engineering knowledge/background so just trying to understand measurement approaches.

I usually measure at 100hz for output impedance. Reason is this is the frequency range that is typically affected most by output impedance on some dynamic driver headphones.

 

[Sal1950]

For now, I say the verdict is quite good for the headphone output of the Emotiva DC-1.

I always enjoyed the sound driving my Sennheiser HD650's

 

[sssn]

Just a friendly question. What is the reasoning for measuring output impedance at 1Khz? I don't have the engineering knowledge/background so just trying to understand measurement approaches.

I usually measure at 100hz for output impedance. Reason is this is the frequency range that is typically affected most by output impedance on some dynamic driver headphones.

An amplifier really shouldn't have hugely varying output impedance over various frequencies. That in itself would be bad engineering.

 

[mindbomb]

Can you do a thd+n x voltage graph for 33 ohms? It is a good way to get information about power and noise in one graph.

 

[Sal1950]

Would really now like to see the current high end (but affordable) Benchmark DAC3 (or even a DAC2) go under the Amir microscope. Interested to see what a extra $1500 or so might bring to the plate from a company that prides itself on top engineering.

 

[Blumlein 88]

Would really now like to see the current high end (but affordable) Benchmark DAC3 (or even a DAC2) go under the Amir microscope. Interested to see what a extra $1500 or so might bring to the plate from a company that prides itself on top engineering.

I second this idea. I would expect the need to get a loaner.

Or as far as it goes, I would like to see an older Benchmark DAC measured for reference. A DAC1 purchased second hand could be measured and then re-sold to recoup the purchase price or very nearly all of it. I know where one is advertised for $450 currently.

I suppose we have JA's measurements already though.
https://www.stereophile.com/content/benchmark-dac1-usb-da-processor-headphone-amplifier-measurements

As well as for the DAC 3 HGC.
https://www.stereophile.com/content...preamplifier-headphone-amplifier-measurements

The DAC1 was very good. The DAC 3 is what you might call SOTA. So what were those $10k, $20k and more expensive devices supposed to provide?

 

[RayDunzl]

The Benchmark DAC manuals come with rather complete AP measurements, if that counts...

https://benchmarkmedia.com/pages/manuals

I could try plugging my DAC2 into the UMC202HD, but I'd suspect the results to be limited by the Behringer.

 

[Blumlein 88]

The Benchmark DAC manuals come with rather complete AP measurements, if that counts...

https://benchmarkmedia.com/pages/manuals

Benchmark has enough credibility to me I would generally accept them. Having others corroborate like in the measurements of JA certainly is a good thing. It does mean there is less benefit to measure it once again.

 

[RayDunzl]

Today's little experiment is running the JBL 308s in parallel with the stereo cheese-subs (twin 150Watt 15's on each side) with a little manual EQ.

Sounds good...

Jim Payne's New York Funk Vol 1

 

[Sal1950]

I suppose we have JA's measurements already though.

As well as for the DAC 3 HGC.

Only thing is for the technically challenged like me, trying to make direct comparisons is difficult.
Where as Amir's overlays of the exact same measurement from the various DUT's gives me a clearer understanding.
Seems like each one of the reviewers are doing things in slightly different ways.

 

[SpeedyRodent]

An amplifier really shouldn't have hugely varying output impedance over various frequencies. That in itself would be bad engineering.

Makes sense. I will have test this theory if I ever get time to get back into learning how to measure amps and dacs.

 

[Blumlein 88]

Only thing is for the technically challenged like me, trying to make direct comparisons is difficult.
Where as Amir's overlays of the exact same measurement from the various DUT's gives me a clearer understanding.
Seems like each one of the reviewers are doing things in slightly different ways.

Yes, that is a big advantage. Overlays for comparison are great. I cannot claim to be a credentialed expert. I might can help make comparisons reasonable among different methods in some cases. In the main, there is nothing in JA's results that to any extent contradict the measurements in the Benchmark manuals.