• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

Review and Measurements of E1DA 9038S BAL Portable DAC & Amp

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
22,046
Likes
32,098
Location
Seattle Area
#1
This is a review and detailed measurements of the E1DA 9038S portable balanced DAC and headphone amplifier. It is the brainchild of the member @IVX. He kindly sent me a sample for review. The cost is stated as "TBD($70)." He will have to tell us if the price is finalized or not.

The 9038S looks like most "thumb drive" DAC and amps with a USB-c connector at one end. Where it departs is that its output is only balanced 2.5 mm jack:

E1DA Portable DAC and Balanced Headphone Amplifier Audio Review.jpg

Given the 2.5 mm, 4 conductor jack, you must use a "balanced" headphone cable with it.

There is a blinking orange LED that shows USB activity that I like. It is not very bright so should not be a bother.

The 9038S weighs essentially nothing. It gets a bit warm but nothing of concern.

There are no volume controls so you have to use the controls in your operating system/player.

@IXV has an audio precision analyzer (series 2) and its claim to fame is very good measurements. BUt let's see how it does using my standardized measurements.

DAC Audio Measurements
Let's start with our dashboard view:

E1DA Portable DAC and Balanced Headphone Amplifier Audio Measurements.png


The output voltage is a bit shy of 4 volt I like to see from balanced DACs but given that this is a portable unit, that can be forgiven. The output is certainly higher than a lot of portable DACs of this type.

The star of the show is the THD+N and hence SINAD (signal over noise and distortion). At essentially 110 dB, this is class leading performance with distortion products at astonishingly low, -123 dB! And that is the highest one. The rest are below -130 dB. The SINAD therefore is dominated by baseline noise, not distortion. WIth that noise well below that of 16 bit audio, this DAC produces audible transparent sound in just about any situation.

The 9038S takes its place in our cherished, top tier of DACs regardless of cost and size:
E1DA Portable DAC and Balanced Headphone Amplifier SINAD Audio Measurements.png


Signal to noise ratio is excellent as well:
E1DA Portable DAC and Balanced Headphone Amplifier Dynamic Range Audio Measurements.png


Signal to noise ratio at just 50 millivolt to simulate output to a sensitive IEM is likewise quite good:

1565758498304.png


Frequency response is just a hair off from flat:
E1DA Portable DAC and Balanced Headphone Amplifier Frequency Response Audio Measurements.png


Jitter test shows the excellence in engineering, keeping all sources of noise and spurious tones out of the DAC's output:
E1DA Portable DAC and Balanced Headphone Amplifier jitter Audio Measurements.png


As the name indicates, an ESS ES9038QM DAC is used. Would it have the dreaded ESS IMD Hump???

E1DA Portable DAC and Balanced Headphone Amplifier IMD distortion Audio Measurements.png


Seems like we have found our second designer (after Topping) which has figured out how to conquer this aspect of ESS implementation. There is only a hint of the hump visible which is totally inconsequential.

What is not inconsequential is matching the Topping DX3 Pro step by step which vast majority of DACs fail to do in desktop size, let alone in a tiny package.

EDIT: Linearity is picture perfect:
E1DA Portable DAC and Balanced Headphone Amplifier Linearity Audio Measurements.png


THD+N versus frequency shows elevated noise/distortion due to wide spectrum of this test:
E1DA Portable DAC and Balanced Headphone Amplifier THD vs Frequency Audio Measurements.png


We can see that the cause is harmonic distortion of high frequencies which are not audible anyway.

Headphone Amplifier Measurements
Let's measure the power versus distortion using 300 ohm load:
E1DA Portable DAC and Balanced Headphone Amplifier Power 300 Audio Measurements.png


At 37 milliwatts, the 9038S blows past anything in its size:

Best Portable Headphone Amplifier 300 Ohm Power.png


And does this while maintaining exceptionally low noise and distortion.

My only other balanced load is 50 ohm:
E1DA Portable DAC and Balanced Headphone Amplifier Power 50 Audio Measurements.png


As you can see, it actually beats the recently tested Sabaj D5 desktop product in how clean it is! Of course, it doesn't have nearly the same power output. But compared to other portable DACs, it is in a class by itself. We are talking a quarter of a watt into 50 Ohm load.

Output impedance is the lowest I have measured but this is with a new optimized harness I built to just test this DAC:
Headphone Amplifier Output Impedance Measurement.png


Headphone Listening Tests
I am waiting for my balanced headphone cable to come in. Will test and report back when it arrives. For now, the power levels predict very good performance.

Conclusions
This is one DAC that you don't want to read by its cover. It looks as ordinary as you can get. But inside lives a potent, highly optimized DAC and efficient headphone amplifier. It shows excellent command of engineering and proper design verification through measurements. The result is a DAC and headphone amplifier which gives many desktop products a run for their money, let alone in this tiny and low cost package.

The requirement for balanced headphone cable may be a barrier to some people as you need to get such a cable for your headphone if you don't have one already.

Overall, it is my pleasure to give my strongest recommendation for E1DA 9038S DAC and headphone amplifier. That is job well done! It put a huge smile on my face to see such strong performance and attention to getting the best performance possible in such a tiny package.

-----------
As always, questions, comments, recommendations, etc. are welcome.

I transferred the balance of my paypal account to my bank account. As a result, it now shows $0.00. That makes me depressed thinking I have no money left!!! so please help replenish that account by donating using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
 
Last edited:

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
22,046
Likes
32,098
Location
Seattle Area
#2
@IVX sent me a video of prototype he has built to support 3.5 mm unbalanced output. Here you also see the guts of it:

 

TonyNL

New Member
Joined
May 7, 2019
Messages
3
Likes
9
#3
Of course everyone will start googling this. It's not easy, but you can start here: https://e1dashz.wixsite.com/index
It's very similar and shares the same model name 9038S.
1565762178023.png
 
Last edited:

THW

Active Member
Patreon Donor
Joined
Nov 21, 2018
Messages
296
Likes
398
#5
This runs entirely on USB power and has no batteries in it, right?
 

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
22,046
Likes
32,098
Location
Seattle Area
#10
According to calculation, this unit only has 65ma current output. I don't know why amir didn't test 32/33ohm here.
My 33 ohm load is unbalanced. Don't have time to build a balanced version right now given my workload.
 

TonyNL

New Member
Joined
May 7, 2019
Messages
3
Likes
9
#13
Last edited:

IVX

Active Member
Patreon Donor
Joined
Mar 3, 2019
Messages
204
Likes
611
Location
South of China, SHZ area
#15
Ohh, thank you for the review. Regarding the SNR, it depends on USB 5V rail quality and current loops around it. I took the video with #9038S tied to the USB OTG Android, powered from power-bank i.e. completely isolated from 230VAC outlet, and you can see the SNR is 122.9-123.8dbA, next I moved my wireless 2.4GHz mouse(DUT AP2702 and mouse on the same table) to stop video record and this action reduced SNR to 121dbA. I submit 1dbA just in case and published -122dbA as specs. -118dbA I never have seen yet but I believe it could be in some particular setup.
 

JohnYang1997

Major Contributor
Joined
Dec 28, 2018
Messages
1,564
Likes
895
Location
Sydney - Australia
#17
Ohh, thank you for the review. Regarding the SNR, it depends on USB 5V rail quality and current loops around it. I took the video with #9038S tied to the USB OTG Android, powered from power-bank i.e. completely isolated from 230VAC outlet, and you can see the SNR is 122.9-123.8dbA, next I moved my wireless 2.4GHz mouse(DUT AP2702 and mouse on the same table) to stop video record and this action reduced SNR to 121dbA. I submit 1dbA just in case and published -122dbA as specs. -118dbA I never have seen yet but I believe it could be in some particular setup.
Amir doesn't weight the noise. His numbers are unweighted.
 

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
22,046
Likes
32,098
Location
Seattle Area
#18
Joined
Jul 2, 2018
Messages
79
Likes
30
#19
Solid performance for such small device. This could be very good option for eg. Office and portable usage.

It seems that no one sells this device at the moment?
 

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
22,046
Likes
32,098
Location
Seattle Area
#20
-118dbA I never have seen yet but I believe it could be in some particular setup.
A few dB difference is really not material here so I would not worry about the discrepancy. My test fixture for headphone jacks is not made to be absolute lowest noise.

But yes, the quality of USB impacts this. I recall my Samsung output was cleaner than my computer's.
 
Top Bottom