Earstudio HUD100 Portable Headphone DAC & Amp Review

[radsonemily]

The THD+N and SINAD measurement here are conducted under Dynamic mode which is DCT(Radsone proprietary advanced dithering) with Radsone-tuned EQ. Our EQ preset boosts bass.

If tested under 'Bypass' mode with no algorithm, the THD+N and SINAD value would be flat on the low- frequency area.

Also, both value are better with standard output

We are sorry that the measured value here is not good, but thank you for sharing the measurement under the Dynamic+High Power mode. If possible, could you please add a measurement under bypass mode with standard output?

 

[Jimster480]

It was sent to me to the company for review.

Don't you mean "it was sent to me by the company to review"?

 

[amirm]

The THD+N and SINAD measurement here are conducted under Dynamic mode which is DCT(Radsone proprietary advanced dithering) with Radsone-tuned EQ. Our EQ preset boosts bass.

If tested under 'Bypass' mode with no algorithm, the THD+N and SINAD value would be flat on the low- frequency area.

Also, both value are better with standard output

Ah yes. I specifically put the switch in bypass mode. But I must have had the unit upside down and instead set it to dynamic! Should have realized that from elevated low frequency noise floor but did not. Anyway, the review is updated:

Max output is 2.2 volts but I dialed it down to our nominal 2 volt output for above.

 

[Cahudson42]

Max output is 2.2 volts but I dialed it down to our nominal 2 volt output for above.

So SINAD is equal to the Apple A2049, except EarStudio is 2.0v out vs. Apple 1.0v. (a plus).

Except both IMO have an anemic output for most anything but IEMs, so if you follow either with an NX3s, does 1v vs. 2v really make any difference?

And, if you look at an LG G7/V20 'tricked' into hi impedance mode, you also get 2V @ 109 SINAD - with DAP to boot.. for $120..

Hard for me to see the EarStudio value proposition..

 

[amirm]

Except both IMO have an anemic output for most anything but IEMs, so if you follow either with an NX3s, does 1v vs. 2v really make any difference?

1 volt versus 2 makes a massive difference.

 

[Veri]

Ah yes. I specifically put the switch in bypass mode. But I must have had the unit upside down and instead set it to dynamic! Should have realized that from elevated low frequency noise floor but did not. Anyway, the review is updated:

Max output is 2.2 volts but I dialed it down to our nominal 2 volt output for above.

That's better

 

[ZolaIII]

Well now it performs satisfactory & we all learned something new how DCT actually did the same what tube amp's do, probably with less fuss & character. Questions that remains is how shouting it off impacted output power.

 

[Veri]

Well now it performs satisfactory & we all learned something new how DCT actually did the same what tube amp's do, probably with less fuss & character. Questions that remains is how shouting it off impacted output power.

Their 'Dynamic' DCT is literally just combined with an EQ. The DCT/dithering itself should not be an audible thing..

 

[ZolaIII]

Their 'Dynamic' DCT is literally just combined with an EQ. The DCT/dithering itself should not be an audible thing..

Should be barely auditable, it's widely used in lossy codecs. We don't know what they did proprietary...

 

[Luyil]

Thanks for the review Amir! I think HUD100 is one of the better options for those who want an unbalanced DAC/AMP that can deliver plenty of power while still remaining portable for commuting. I'm interested in something portable without batteries (as I'm terrible at remembering to recharge / have a phone with good enough battery juice) which that can fit in the pocket if needed. I suspect many here are overestimating the size of the HUD100. While it is larger than E1DA & Hidizs S8, it is much smaller than the Dragonfly Red and DACport HD. It does not deliver as much power as the DACPort HD, however it does have considerably better distortion numbers than the DACport HD on the power vs distortion graphs, especially under 300O. Overall think HUD100 isn't the best at anything, but it is quite a powerful yet extremely portable unbalanced USB DAC/Amp, so I can see why it is recommended. Dont think there is something that is more portable than the HUD100 that can deliver more unbalanced power at lower distortion levels. Hidizs S8 does come close in the power department though.

Still think the price is quite steep though, so will probably wait for a deal where the price is in the double digits.

DACport HD: 7.6 x 2.8 x 1.0 cm = 21.28cm3 & ~35g
Dragonfly Red: 6.2 x 1.9 x 1.2 cm = 14.14cm3 & 22g
Earstudio HUD100: 4.5 x 3.2 x 0.8 cm = 11.52cm3 & 22g
E1DA 9038s: 4.8 x 2.2 x 0.9 cm = 9.50cm3 & 10g
Hidizs S8: 4.7 x 1.88 x 0.78 cm = 6.89cm3 & 9g

Topping NX3s: 10.7 x 6.6 x 1.36cm = 96.04cm3 & 157g

 

[Asylum Seeker]

Thanks for the review Amir! I think HUD100 is one of the better options for those who want an unbalanced DAC/AMP that can deliver plenty of power while still remaining portable for commuting. I'm interested in something portable without batteries (as I'm terrible at remembering to recharge / have a phone with good enough battery juice) which that can fit in the pocket if needed. I suspect many here are overestimating the size of the HUD100. While it is larger than E1DA & Hidizs S8, it is much smaller than the Dragonfly Red and DACport HD. It does not deliver as much power as the DACPort HD, however it does have considerably better distortion numbers than the DACport HD on the power vs distortion graphs, especially under 300O. Overall think HUD100 isn't the best at anything, but it is quite a powerful yet extremely portable unbalanced USB DAC/Amp, so I can see why it is recommended. Dont think there is something that is more portable than the HUD100 that can deliver more unbalanced power at lower distortion levels. Hidizs S8 does come close in the power department though.

Still think the price is quite steep though, so will probably wait for a deal where the price is in the double digits.

DACport HD: 7.6 x 2.8 x 1.0 cm = 21.28cm3 & ~35g
Dragonfly Red: 6.2 x 1.9 x 1.2 cm = 14.14cm3 & 22g
Earstudio HUD100: 4.5 x 3.2 x 0.8 cm = 11.52cm3 & 22g
E1DA 9038s: 4.8 x 2.2 x 0.9 cm = 9.50cm3 & 10g
Hidizs S8: 4.7 x 1.88 x 0.78 cm = 6.89cm3 & 9g

Topping NX3s: 10.7 x 6.6 x 1.36cm = 96.04cm3 & 157g

Shanling UP2
volume control, BT functionality, self-powered
67mW@32 Ohm (claimed)
18cm3
26g
$79
You can set it to draw power from your device thereby eliminating the need to charge it separately.

 

[Zerohour]

Glad to see the HUD100 still maintains the company's track record, even though it is a bit pricey considering today's market

no worries Amir, I'm sure lots of people understand that when you "recommend" something, its not an absolute and that it depends on preference/requirements.

 

[wyup]

1 volt versus 2 makes a massive difference.

As per the graphs, I don't see the point of having a low (1V) powered connection, the high powered (2V) performs the same as the low at 33 ohms with much more power and less distortion. And as for 300 ohms, the low powered isn't practical, and it even has more distortion at near max power, where it would be most needed.
Hidizs S8 as a headamp has lower distortion at all power scale points at 33 ohms compared to HUD100. Yes it has 138mw of power compared to 65mw, but would I need them to power sensitive low impedance headphones?
The benefits of high power (supposedly better amp) in my opinion are counterbalanced by high dac noise and middle-of-the road SINAD.
@amirm could this noise at dac sinad be due to noisy usb pc out? Did you use the same usb port as with Hidizs S8 to be that noise clean in comparison?
Small portable dac-amps make more sense for IEMs and low impedance headphones, I don't see myself commuting with a HD650 or DT880pro...

 

[Ron Texas]

Looks OK, although not earth shaking.

 

[darmanastartes]

@amirm could you test in DCT mode? (the middle setting) I would like to see what impact, if any, Radsone's "proprietary advanced dithering" tech has on the measurements.

 

[fieldcar]

I just got mine after Zeos posted a coupon to bring it down to $120. It appears that zeos's coupon is dead, but there is a fathers day sale from now until 6/22/2020.

Anyway. I had major issues with the Dynamic mode with a few songs mastered to a higher level, and contacted support over the issue.

I found that music in tidal or spotify that is mastered to a peak of -1dB instead of the usual normalization of -3dB will exhibit heavy clipping distortion no matter the output volume level in windows. Radsone even confirmed that I need to get it to -3dB to prevent the distortion in dynamic mode. So it's a flaw that they probably wont fix. I don't really mind it since I don't want any EQ going on in the DAC anyway.

 

[Spirit Roxas]

A possible replacement or upgrade from topping nx4? I use the topping nx4 with the laptop but I never use it for portability so battery could give out someday. Also I have the sennheiser 58x and moondrop starfield. May get the Sundara in the future.

 

[Veri]

A possible replacement or upgrade from topping nx4?

The NX4 is a lot more powerful. Not sure this one can drive the Sundara..

 

[fieldcar]

The NX4 is a lot more powerful. Not sure this one can drive the Sundara..

Are you sure? The NX4 appears to have ~147mW@33Ohm vs the HUD100 putting out 138mW@33Ohm on the high output jack.

As for driving the Sundara (37 ohms / 94 dB), I'm sure it will work as it's similar to my HE4XX's (35 ohms / 93 dB). It works, but it's basically maxed, and while I don't hear any tone change or audible distortion, I'm sure it's distorting. 100% volume is at just a tad under what I consider loud. It can't replace my stacks, but dang its impressive for its size and throwing in my laptop bag for on the go use.

 

[Veri]

Are you sure? The NX4 appears to have ~147mW@33Ohm vs the HUD100 putting out 138mW@33Ohm on the high output jack.

As for driving the Sundara (37 ohms / 94 dB), I'm sure it will work as it's similar to my HE4XX's (35 ohms / 93 dB). It works, but it's basically maxed, and while I don't hear any tone change or audible distortion, I'm sure it's distorting. 100% volume is at just a tad under what I consider loud. It can't replace my stacks, but dang its impressive for its size and throwing in my laptop bag for on the go use.

In that case, maybe it'll work I thought the Sundara required more powah