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

[solderdude]

Didn't IVX say there were 2 cases of people burning things out by doing that?

But do we know if they used the correct conversion cable.
When one were to use an XLR input with fantom supply or one with pins connected to ground or one which doesn't like DC input or has DC on its input it is easy to destroy the 9038S.

With the correct cable and normal balanced amplifier input there should be no blowing up anything.

 

[th0m]

Isn't there a 9038X on the way as well? Maybe that one will have Home-DAC mode in addition to being balanced.

 

[magor34]

It should work, I mailed Ghent audio to make such a cable and I had no problems using it.
But might be more prudent to wait for 9038d which has Home DAC mode and use 3.5mm to RCA cable.

I reckon it would be a good idea to start listing reliable 2.5mm to 2x XLR cables and other cables respectively to each use case. Perhaps on the E1DA discord, with links to purchase them. Links to AliExpress, eBay and others with more or less global availability.

It would likely mitigate the amount shorted 9038s units.
I for one would like to buy the 9038s and a “certified” working Stereo XLR cable to use with PA systems without frying the thing right away.

 

[somebodyelse]

I reckon it would be a good idea to start listing reliable 2.5mm to 2x XLR cables and other cables respectively to each use case. Perhaps on the E1DA discord, with links to purchase them. Links to AliExpress, eBay and others with more or less global availability.

It would likely mitigate the amount shorted 9038s units.
I for one would like to buy the 9038s and a “certified” working Stereo XLR cable to use with PA systems without frying the thing right away.

As @solderdude pointed out the cable isn't the only issue - you need detailed knowledge of the input stage you're connecting to, and its implications, not just that it uses an XLR. If you need a list of cables then you don't know enough to use them safely. In @IVX's position I'd strongly discourage use of this sort of cable as there's a significant chance of damage.

As a practical example the old Quad 520f has an XLR input which may or may not kill the 9038s depending on which factory options were selected when the amp was ordered. There's no obvious external difference. If you know enough to find out which is which you know enough to order/make the right cable.

 

[Veri]

Yep this is why @IVX would rather say "please don't do it", so to avoid any freak accidents.

 

[IVX]

I said one guy burned the DAC, another guy successfully connected with some exotic preamp with trafo inputs.

 

[magor34]

As @solderdude pointed out the cable isn't the only issue - you need detailed knowledge of the input stage you're connecting to, and its implications, not just that it uses an XLR. If you need a list of cables then you don't know enough to use them safely. In @IVX's position I'd strongly discourage use of this sort of cable as there's a significant chance of damage.

As a practical example the old Quad 520f has an XLR input which may or may not kill the 9038s depending on which factory options were selected when the amp was ordered. There's no obvious external difference. If you know enough to find out which is which you know enough to order/make the right cable.

Honestly I don’t know enough about soldering and wires to figure it all out. Or enough to gamble on it.
So let me ask you directly (and any anyone willing to help), what cable would I need to hook this up to a mixing console with two 3-pin XLR inputs? Surely there’s a premade cable out there to safely use with a mixer?
I’m asking cause I don’t even know what wiring standard the 9038 uses, assuming there’s multiple 2.5mm balanced standards.
And so you don’t think I’m a complete moron... I won’t be using any phantom power (+48v) on the mixer with this device

 

[Earfonia]

Honestly I don’t know enough about soldering and wires to figure it all out. Or enough to gamble on it.
So let me ask you directly (and any anyone willing to help), what cable would I need to hook this up to a mixing console with two 3-pin XLR inputs? Surely there’s a premade cable out there to safely use with a mixer?
I’m asking cause I don’t even know what wiring standard the 9038 uses, assuming there’s multiple 2.5mm balanced standards.
And so you don’t think I’m a complete moron... I won’t be using any phantom power (+48v) on the mixer with this device

From experience, I guess the following connection would work, but do it at your own risk, I'm not responsible for any blown up 9038S

2.5mm --- XLR Left & Right
L- >>> pin 3 XLR Left
L+ >>> pin 2 XLR Left
R- >>> pin 3 XLR Right
R+ >>> pin 2 XLR Right

Be very careful getting cables from AliExpress like this one:
https://www.aliexpress.com/item/329...chweb0_0,searchweb201602_1,searchweb201603_55

As we don't know how they connect the pins. If they connect the L- and R- to XLR pin 1 it would probably burn the DAC.
And don't forget to switch off phantom power of the XLR ports.

 

[Veri]

I asked Ghent audio to make this cable, according to @solderdude's instructions

2.5mm TRRS -> 2x XLR 3-pin
Tip -> pin-3 Right channel (R- signal or RN)
Ring (next to tip) -> pin-2 Right channel (R+ signal or RP)
Ring (next to sleeve) -> pin-2 Left channel (L+ signal or LP)
Sleeve -> pin-3 Right channel (L- signal or LN)
pin 1 and screen are left open on both XLR connectors

The resulting cable works without issues.

 

[headwhacker]

I asked Ghent audio to make this cable, according to @solderdude's instructions

2.5mm TRRS -> 2x XLR 3-pin
Tip -> pin-3 Right channel (R- signal or RN)
Ring (next to tip) -> pin-2 Right channel (R+ signal or RP)
Ring (next to sleeve) -> pin-2 Left channel (L+ signal or LP)
Sleeve -> pin-3 Right channel (L- signal or LN)
pin 1 and screen are left open on both XLR connectors

The resulting cable works without issues.

No hint of hum from mains noise? People in discord chat always mention that a hum noise could be a problem due to a floating ground in the XLR input for anyone who asked about connecting 9038S to a balanced amp like THX 789.

 

[Tks]

No hint of hum from mains noise? People in discord chat always mention that a hum noise could be a problem due to a floating ground in the XLR input for anyone who asked about connecting 9038S to a balanced amp like THX 789.

Odd, wouldn't that be rectified the moment you connected the device to a computer's USB port?

 

[Earfonia]

No hint of hum from mains noise? People in discord chat always mention that a hum noise could be a problem due to a floating ground in the XLR input for anyone who asked about connecting 9038S to a balanced amp like THX 789.

In Pro Audio it is common to disconnect the ground (XLR ground) to remove hum caused by ground loop. From my experience so far, floating input ground usually doesn't cause problem.

 

[headwhacker]

In Pro Audio it is common to disconnect the ground (XLR ground) to remove hum caused by ground loop. From my experience so far, floating input ground usually doesn't cause problem.

So it is more of a good thing than bad. Possible the report of busted 9038S connected to a balanced amp using xlr cable is wrong pin assignment.

 

[Veri]

So it is more of a good thing than bad. Possible the report of busted 9038S connected to a balanced amp using xlr cable is wrong pin assignment.

No it could be a hum is picked up, just seems unlikely to happen. If it does happen you're kinda SOL. With 3-pin XLR it really shouldn't happen though but considering this is 2x 2-pin wiring, it's not impossible.

 

[somebodyelse]

So it is more of a good thing than bad. Possible the report of busted 9038S connected to a balanced amp using xlr cable is wrong pin assignment.

Or the cable is correct but the amp input is incompatible.

 

[Veri]

I would expect headphone amps to deal with it fine, but for speaker amps it might be a very bad match indeed.
For these reasons I believe IVX doesn't like people using such a cable. But hey it worked for me. Just tread with care.

 

[Nicosea]

Anyone knows when the 9038D (unbalanced output) will be available and expected to be sold?

 

[Zoide]

Anyone knows when the 9038D (unbalanced output) will be available and expected to be sold?

@IVX will probably recommend that you check his Discord for the latest information

 

[IVX]

I hold on the release so far because I hope I'll change Cmedia CM6642 USB/audio bridge IC to Realtek or Savitech or whatever. CM6642 has design defect(yesterday cmedia confirmed that they can't improve that on the current silicon version) and it doesn't check CRC of audio data, hence it may send random junk instead of valid audio data in the case of unstable USB connection. In the real portable world, where are dust and cable shaking, it is a problem.

 

[Tks]

I would expect headphone amps to deal with it fine, but for speaker amps it might be a very bad match indeed.
For these reasons I believe IVX doesn't like people using such a cable. But hey it worked for me. Just tread with care.

What's your setup lookin like Veri if you don't mind me asking?