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

[infinitesymphony]

Actually, can't realize why so many people want unbalanced 3.5mm if most of decent HP for sure balanced?

My guess is a some people are planning to use it with a regular amp and speakers.

Exactly. We'd like to be able to use it as a standalone DAC rather than a DAC/amp. I would like the ability to output a line-level signal to two balanced 1/4" TRS or XLR connectors, or 3.5mm to two RCA connectors for unbalanced.

With either of those features, this could be king of the hill in terms of budget USB DACs, the main competitors being the Khadas Tone Board (differences: unbalanced RCA outputs, S/PDIF input) and the Apple USB-C to 3.5mm headphone jack adapter (differences: unbalanced 3.5mm output, inferior performance).

 

[Johnb]

Question for Amir: Sinad at -109db, highest distortion product at <-120db, 3rd harmonic. Usually Sinad is slightly lower than highest spike. Here we have 11db difference. I would then assume that noise is high, but that is not the case, looking at both power graph and IMD graph. I know that there is distorion at ultrasonic freq, but I thought that the dashboard is bandwidth limited to around 20khz.

 

[amirm]

Question for Amir: Sinad at -109db, highest distortion product at <-120db, 3rd harmonic. Usually Sinad is slightly lower than highest spike. Here we have 11db difference. I would then assume that noise is high, but that is not the case, looking at both power graph and IMD graph. I know that there is distorion at ultrasonic freq, but I thought that the dashboard is bandwidth limited to around 20khz.

I will have to think about it more to figure out the exact reason for discrepancy. For now, the dashboard uses 22.4 kHz bandwidth whereas the Dynamic Range test uses 20 kHz. It also applies weighting to the measurements so that improves things again. See AES-17 specifications for how this is measured.

 

[bidn]

Hello Amirm and all,

I just joined your forum and this is my first post.
I had been enjoying reading the reviews and posts here for long.
But the stellar (actually a black hole-ish) review about the TotalDAC moved me to join,
(at some point, due to Jude's assessment at Head-Fi, I had even considered purchasing one, I luckily never expended so much money. And then this site has been exposed how awfully it performs compared to its price, also synthesizing fake details not present in the recording and being advertised with a deceiving SNR curve created with a -120 dB signal -- who pays attention to this,? the super-cheap transformer being sold as a super-expensive power supply, and so on... what a gigantic unmasking that was! It should have been like a huge nuke causing an earthquake, shaking and turning the audiophile world upside down, but I fear ASR is made into something "audiophilly incorrect" on other forums).
and now such another stellar (this time in the opposite, positive sense) review about a tiny and inexpensive device performing so incredibly well!
I couldn't resist more and joined the forum, these reviews are by far the best things I know of for the audio world!

IVX, congratulations for your so outstanding work with the E1DA !
I am interested in buying it (having a 2,5 mm--> XLR-4 adapter for my headphones nd some power hungry earphones with a 2,5 mm cable),
but like other persons I am also interested in other versions :
- one with a 3,5mm connector
- and even more interesting for me: some versions (2,5 or 3,5 mm) with a larger enclosure incorporating a volume knob or wheel ( I find it unpractical to reach to the display of a computer or smartphone to adjust the volume).

BTW I purchased a RME ADI-2 Pro not long after it was issued (before they started exporting it to the US), I am glad I made a good choice with RME!

All the best and have a nice weekend,
bidn

 

[Xulonn]

I'm thinking about buying a pair of headphones and getting a E1DA to use with my computer. It looks like open back is best for me, because my previous objections to headphones were being isolated from outside sounds like knocking on my door or my phone ringing. During my surfing for info and reviews, I came across the headphones.com which has a page with an excellent discussion of balanced circuit including the difference between balanced drive a fully balanced headphone system - LINK - and lots of diagrams to help visualize the differences.

In short, balanced headphones are just regular headphones that have been re-cabled to a different plug.

Edit: Add LINK for DIY headphone wiring and modifications, including TRS, TRRS and microphone wires. Once the headphones are wired correctly with this plug, I believe that it will work for the C1DA, and then adapters can be used to go to XLR, RCA, etc. for other devices.

 

[Xulonn]

As I looked at TRRS wiring variants - it can be confusing - It looks like there is no standard (yet).

According to Solderdude's comment on Page 4 of this thread, the C1DA uses a 2.5mm TRRS that matches the A&K / FiiO configuration below.

Is that correct?

 

[Hemi-Demon]

Today I sent #9038Dv0 gerbers pack to make PCB samples. Next few days will try it. I have added:

1) softstart to limit inrush current and let work with mobiles without Y-splitter. Actually, a big output power peaks anyway will off USB OTG power rail ))

2) Seems max power at 16ohm will be limited anyway. 32ohm I hope will produce similar 340mW but @16ohm maybe just 400mW or so
3) Optimized I/V stage for minimal noise, simulations show up to 125dbA, let's see
4) A lot more part on both sides. Becomes expensive.
5) Regarding THD #9038S seems to stay unbeatable. And cost-effective as well. Actually, can't realize why so many people want unbalanced 3.5mm if most of decent HP for sure balanced?

Perfect!! Hope it works as I would like to use this with my smartphone. So a smartphone type c output, wont event power the current #9038s?

 

[Tks]

To be abundantly clear... One can NOT use single ended headphones with any (truly) balanced device. ONLY balanced (4-wire) headphones.
Regardless what kind of aftermarket 'adapters' are available and how much one may want these to work.

The THX 789 would be one of these not (truly) balanced devices where this would suffice. Also I think you wouldn't even need adapters, you could just run unbalanced into the amp, yet still use the Balanced Headphone-out and still reap the power benefits, correct?

 

[solderdude]

yes you can used both balanced and truly balanced amplifiers, that's why truly is between hooks..

 

[solderdude]

As I looked at TRRS wiring variants - it can be confusing - It looks like there is no standard (yet).

According to Solderdude's comment on Page 4 of this thread, the C1DA uses a 2.5mm TRRS that matches the A&K / FiiO configuration below.

Is that correct?


View attachment 31530

Correct.
The other ones are all 3.5mm and Pentaconn.
Indeed it is something to take in consideration when buying/making a conversion cable for 3.5mm connectored headphones.

 

[Nango]

As I looked at TRRS wiring variants - it can be confusing - It looks like there is no standard (yet).

According to Solderdude's comment on Page 4 of this thread, the C1DA uses a 2.5mm TRRS that matches the A&K / FiiO configuration below.

Is that correct?


View attachment 31530

This actually is the pin assigning of all new Onkyo/Pioneer DAP 2,5mm TRRS, it differs slightly from above in your chart:

 

[IVX]

guys, I vahe a render for the pinout https://e1dashz.wixsite.com/index/products?lightbox=dataItem-jwceud87

 

[solderdude]

This actually is the pin assigning of all new Onkyo/Pioneer DAP 2,5mm TRRS, it differs slightly from above in your chart:

View attachment 31543

actually it doesn't

 

[graz_lag]

In fact it looks identical to the 2.5mm TRRS used by FiiO ...

 

[tower2010]

Will it have enough power to drive the Sennheiser HD650? Thanks.

 

[Labjr]

Seems like there's a new DAC out every few days which takes the price/performance title from the previous week's DAC!

Congratulations IVX! And best wishes on your success!

I wonder if you'll be developing ultimate performance balanced DACs and headphone amps for home desktop use, where you don't have the limitations of USB power and tiny enclosures? Also need line level outputs for my stereo? Oh and DSD? Thanks.

 

[Tks]

Seems like there's a new DAC out every few days which takes the price/performance title from the previous week's DAC!

Congratulations IVX! And best wishes on your success!

I wonder if you'll be developing ultimate performance balanced DACs and headphone amps for home desktop use, where you don't have the limitations of USB power and tiny enclosures? Also need line level outputs for my stereo? Oh and DSD? Thanks.

If only we had other electronic industries like TV's or computer parts doing the same in similar fashion of time.

Oh and monitors.. ESPECIALLY monitors, goodness lord what a slow industry this is for any sort of progress..

 

[IVX]

I believe 3.5BRMS is enough for HD650, yes, power is not too big just 40mW but the sensitivity of HD650 >100db so I expect SPL level around 120db. I.e. as HFM HE400i, Phantom, LCD2 etc. Someone already reported in my discord channel about HD800s sounds "on spot" with my DAC so I think HD650 no problem.

 

[IVX]

As I said, I have an idea regarding such desktop DAC, probably just like a board(to keep it inexpensive), with self-calibration. Without such novelty, I don't want to spend time for just 1 more desktop DAC - boring.

 

[Veri]

As I said, I have an idea regarding such desktop DAC, probably just like a board(to keep it inexpensive), with self-calibration. Without such novelty, I don't want to spend time for just 1 more desktop DAC - boring.

Self-calibration sounds really cool