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

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fo


For XLR to RCA = 2-XLR to center pin RCA, 1-XLR to sleeve RCA
For RCA to XLR = centerpin RCA to 2-XLR and sleeve to 1+3 XLR.

These adapters do not work the other way around.
I was thinking about this a bit yesterday, electrically, will it be okay when we have one pin with an active signal to be NC? I am talking about XLR>RCA cable, more specifically about negative pin (pin 3).
 

bravomail

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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?
Most headphones sold today are unbalanced. People wouldn't want to buy a new headphone just for trying a new DAC/Amp. There is no easy way to convert balanced output to unbalanced input. My proposal would be to have 2 versions of your 9038S - with balanced and unbalanced output. You can then see for yourself which one will be selling better. BTW Great engineering work!
 

Veri

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Most headphones sold today are unbalanced. People wouldn't want to buy a new headphone just for trying a new DAC/Amp. There is no easy way to convert balanced output to unbalanced input. My proposal would be to have 2 versions of your 9038S - with balanced and unbalanced output. You can then see for yourself which one will be selling better. BTW Great engineering work!
The unbalanced is in the work :)
 
OP
amirm

amirm

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Thread Starter #265
Most headphones sold today are unbalanced. People wouldn't want to buy a new headphone just for trying a new DAC/Amp. There is no easy way to convert balanced output to unbalanced input. My proposal would be to have 2 versions of your 9038S - with balanced and unbalanced output. You can then see for yourself which one will be selling better. BTW Great engineering work!
A lot of the cleverness in this device is due to being balanced. That produces a lot more output which makes it suitable for many headphones. Take that away, i.e. provide 3.5 mm connection, and there may not be much value to set it apart from other devices.

If the cable is removable on your headphone, see if you can find a cheap balanced cable or make it yourself.
 

sajunky

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A lot of the cleverness in this device is due to being balanced. That produces a lot more output which makes it suitable for many headphones.
The most important is a fact that it is easier to manufacture. Balanced I/V conversion is a part of ESS design. It is how they achieved low distortion figures. It makes easy to make a balanced output, as is already there. SE output would require additional opamps and we don't know how it would affect internal ground loops, it may require better filtering of PSU rails, etc..
 

IVX

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sajunky
100% correct. That's why I didn't promise the same THD performance for the new 9038D. However, I already see a few db better S/N, because of lower noise opamp used in I/V stage, and 8397 works with lower gain. Also, I have to use 4 layers PCB instead of cheap 2 layers as 9038S + about 30% more part list, and very busy 2 side soldering SMD. So 3.5mm unbalanced isn't optimal at all, especially if a nice looking balance cable 2.5,mm/MMCX 1.2m 225mOhm/wire just $15.
 

solderdude

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I was thinking about this a bit yesterday, electrically, will it be okay when we have one pin with an active signal to be NC? I am talking about XLR>RCA cable, more specifically about negative pin (pin 3).
It is the only way unless you use a transformer
 
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It is the only way unless you use a transformer
Could I take the 2.5mm output of the 9038S or PowerDAC into a transformer volume control with balanced inputs and then output to power amps on the stereo?

The PowerDAC v2 functions really interest me, though. Really cool functions.
 

IVX

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The trafo is ok option as well, maybe that approach steady associated with high THD tube-amps, however, any Audio Precision analyzers outputs are isolated by Jensen's trafo with -135db harmonics level. For THD<.01%@20Hz and 3.5VRMS you need a quite big one trafo, be aware.
 

solderdude

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Could I take the 2.5mm output of the 9038S or PowerDAC into a transformer volume control with balanced inputs and then output to power amps
You can connect the 9038 to any balanced input and headphone
 

solderdude

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Hi Patrick:

I was following up @solderdude and @infinitesymphony comments about the possible conversion from the 2.5mm TRRS (Fiio or A&K) to 2 x XLR plugs, as I would like to be able to test this E1DA 9038S as USB DAC feeding the analog XLR inputs of my HK990 integrated stereo amplifier.
This option, if possible, would be in parallel to my current one, in which the Singxer F-1 USB-S/PDIF interface feeds the HK990 on-board DAC section.

However, still waiting the confirmation by @IVX @solderdude whether the said setup is feasible.

@Veri thank you for reassuring abt. the vendor Lunashops!
(I believe they can easily arrange customized items in terms of XLR pin arrangement and cable length.)
Yes this is possible
R+ to 2-XLR right channel
R- to 3-XLR right channel
L+ to 2-XLR left channel
L- to 3-XLR left channel
 

graz_lag

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Yes this is possible
R+ to 1-XLR right channel
R- to 3-XLR right channel
L+ to 1-XLR left channel
L- to 3-XLR left channel
Thank you!
Does this E1DA 9038S offer the 'DAC only mode'? I mean, is there any potential issue in feeding my integrated amplifier analog XLR inputs from the jack designed to power headphone ...
 
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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.
Hi IVX,
Yes, it does have enough power for the HD650 in real life as well.
 
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