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

[XeCutor]

i have an android smartphone.
I thought a power bank could connect between the 9038D and the smartphone.
If I can't connect the power bank to the 9038D I will have to buy another DAC / AMP.

Disclaimer: I don't use it that way, I use it with a computer 99% the time and 1% of the time connected with a usb-c to usb-c cable to an Android phone.

That said I don't think there's anything a all preventing hooking in a power bank in the middle as long as you have an appropriate cable or powered hub in-between. There's an example of a potential cable on the sibling product here (5th picture): https://www.aliexpress.com/item/4000078625548.html

You'd need an additional adapter or cable to complete the setup, for example an usb-a to usb-c cable, provided your phone uses usb-c.

Please set me straight if this doesn't work with the 9038D for some strange reason, the closest I have first hand experience of is having a powered usb hub in-between and that works just fine at least, but is even bulkier.

 

[Lana2177]

Hi everyone, i'm kinda new to this dac-amp world, i want to know if the 9038D could power the Hifiman Sundara?

 

[XeCutor]

Yes, unless you're looking for ear-damaging volume. I'm using this exact combination and my normal listening volume is around 40%. If you want a lo-fi speaker setup using your headphones just place the Sundaras on your desk or a stand and crank up the volume to 100%. The sound output driven by 9038D is comparable with what my Lenovo Carbon X1 laptop produces from it's built in speakers on 50% volume, same distance to listener, sound quality is probably better with the Sundara-speakers but obviously awful compared to wearing the cans like you should.

 

[Lana2177]

Yes, unless you're looking for ear-damaging volume. I'm using this exact combination and my normal listening volume is around 40%. If you want a lo-fi speaker setup using your headphones just place the Sundaras on your desk or a stand and crank up the volume to 100%. The sound output driven by 9038D is comparable with what my Lenovo Carbon X1 laptop produces from it's built in speakers on 50% volume, same distance to listener, sound quality is probably better with the Sundara-speakers but obviously awful compared to wearing the cans like you should.

Wow that's impressive, thanks for replying btw, I would buy it now.. Cheers

 

[Viennacalling]

@amirm
please can you Test 9038D as a christmas surprise for me

 

[Veri]

@amirm
please can you Test 9038D as a christmas surprise for me

Ha-ha

 

[WoodyLuvr]

Anyone know what the 9038D's output power (mW) is @ 150 Ohms@1kHz? I know that max output is ~2.75Vrms.

 

[IVX]

WoodyLuvr, 50mW or close to. OPA1622 with +/-5Vdc rails has a voltage limit at 2.75Vrms and the current limit at 110mA@25C. In your case only voltage limit involved, hence, 2.75^2/150 = 50mW.

 

[Zerobrsss]

Hello everyone. Have a question: 9038d works with iphone 7 without additional power or i should use, for example, power bank and y-cable??

 

[wasnotwasnotwas]

Hello everyone. Have a question: 9038d works with iphone 7 without additional power or i should use, for example, power bank and y-cable??

I think you need an apple camera kit or simlar. Search this thread, it has the answer, somewhere

 

[Zerobrsss]

I think you need an apple camera kit or simlar. Search this thread, it has the answer, somewhere

I found some type c to lightning adapters that could transfer audio from dac’s like 9038d (meenova brand), but it doesn’t have additional power.

 

[wasnotwasnotwas]

I found some type c to lightning adapters that could transfer audio from dac’s like 9038d (meenova brand), but it doesn’t have additional power.

I believe iphones need additional power for the 9038, its not just the cable connection

 

[Zerobrsss]

I believe iphones need additional power for the 9038, its not just the cable connection

Ok, thanks for your answers!

 

[IVX]

Zerobrsss, please try to ask our discord channel, they know the solution. Some lightning2USB adapter with 200mA load ability.

 

[chi2]

Hello everyone. Have a question: 9038d works with iphone 7 without additional power or i should use, for example, power bank and y-cable??

While 9038SG3 works with iPhones without any additional power source, 9038D doesn't.

 

[chi2]

With the 9038SG3 a decoding cable like the Meenova or Penon or the Apple camera adapter is still needed but no additional USB power source. The 9038D needs both.

 

[cqtek]

Hello to all.

On Tuesday I got the E1DA 9038D, it took only 8 days to get from China to Spain, quite a record!

I listened to it a bit and then made some measurements. I am not completely satisfied with them. When empty it reaches almost 3V. I tried with a resistance of 15 Ohms and almost gave the 120mW specified, my measurements gave 110mW, not bad. However, at 33 Ohms it was not so good. The best measurement, with no visible distortion, gave about 2.1V at 1kHz. Turning up the volume, the curve became saturated. I checked if the measurement was consistent with another multimeter, which even measured less voltage. Well, I will rely on my small and cheap oscilloscope. But 2.2V gives 150mw and not 180mW specified (that would be 2.4V).
Of course, the measurement was stable over the entire audible range, which confirms that the frequency response is flat even at the limit of its power.

The measurements were made with the Tweak_9038D_C.hex firmware and with the 9038D configured at 0dB.

Is there something wrong with my measurement methods? I don't know...Although, at these power levels, 20 or 30mW is not very important either, a difference between 0.2 or 0.3V.

 

[Veri]

The measurements were made with the Tweak_9038D_C.hex firmware and with the 9038D configured at 0dB.

Looks like it's being driven into clipping. Is that the default firmware?

 

[cqtek]

Looks like it's being driven into clipping. Is that the default firmware?

No, it is not the default firmware. But can the firmware reduce the power? It is possible, but in any case, it should be notified. I can try it with other firmwares as soon as I have some time.

 

[IVX]

cqtek, the power was specified for THD+N = 1% i.e. the same way as a power amp's standard power measurement. Another factor that affects the power performance is USB 5Vdc rail.
I took a look for your pics closer and noticed that you used 11ohm(brown/brown/black/gold/black) 2 resistors in serial = 22ohm and got 2.37Vrms with clipping, is that correct?

PS: ah, I see it was ornage/orange so 33ohm and resistors are no in serial, I see now with zoom in. Actually, OPA1622 has >100mA current limit at 25C, hence not clipped voltage should be 33ohm*.1A = 3.3Vpeak or 2.333Vrms i.e. 165mW + some gain to reach THD+N 1% and 180mW has to be there. Could you please check the unclipped voltage without load, and 5Vdc USB rail under load as well?
THD 1% looks like that: