This is a review and detailed measurements of the Zorloo Ztella MQA portable USB-C headphone and DAC "dongle." It was kindly sent to me by a member. The Ztella comes in two version: MQA version that I have which costs US $99 and "standard" version for US $65.
As dongles go, the Ztella is on the attractive side:
The cable has a nice jacket so hopefully lasts longer than the throw-away kind. Even the USB-C adapter is nice quality as you see in the picture.
I tested the Ztella on my Windows PC. There, typical of these dongles, the ASIO interface I use was truncating 24 bit audio to 16 bits. So for some of the tests, I used my Roon player in exclusive (WASAPI bit-exact) to avoid that issue. Note that this class of device also relies on the system device volume so be sure to check that.
Also, when I first plugged the unit in with a 33 ohm load, it reduced its output to half. This stayed so even after I plugged in a higher impedance load into it. I needed to unplug and plug it back in to get it to output the full voltage. This kind of behavior is typical of these dongles as they attempt to control the maximum power consumption.
In use the Ztella gets a bit warm which goes with the territory of higher power output it provides.
Audio Measurements
Here is our usual 1 kHz dashboard:
The best news here is 2 volt output as many dongles limit at 1 volt which severely reduces their power with high impedance headphones. On the down side we have a ton of noise spikes in the FFT spectrum (top right). This is likely system dependent and due to lack of sufficient filtering. There is just not much space in these dongles to put in proper filters. This may be the reason my measured performance is worse than the company's. And your phone may be more quiet than my desktop computer as well. As it is, SINAD falls in a region which is considered very good for dongles:
Even though I had to use the interface that truncates to 16 bits (and hence introduces some distortion), intermodulation distortion is quiet low:
Jitter performance is ugly because of the previously mentioned system noise bleeding through:
Again, most dongles are different shades of bad here.
Dynamic range is not as good as I like to see because of the noise issue:
Power Measurements
The problems above may not be audible. But what is guaranteed audible is lack of power so let's look at that using both 300 and 33 ohm loads:
I can predict with almost 100% accuracy that this level of power provides a very satisfying experience. And raises to almost top of our charts:
Output impedance is nicely low:
Headphone Amplifier Listening Tests
I only had time to listen using my Sennheiser HD-650 headphones. Here, performance was excellent. There was plenty of powerful and clean bass that was hard to imagine coming out of this little dongle. The only time I wished for a bit more power was with recordings that were not recorded loud.
Conclusions
The Zorloo Ztella MQA has good distortion measurements combined with lots of power in a tiny package. This results in very nice listening experience. Alas, the $99 price is quite high for a dongle. So unless something else is taken out, I would get the non-MQA standard version.
I am happy to recommend the Zorloo Ztella MQA headphone adapter.
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As always, questions, comments, recommendations, etc. are welcome.
Today is a sad day. Had my back to my photo stand and heard its backdrop fall down as it often does. Sadly this time it had a pink panther on it and poor "guy" lost its left arm as it hit the floor.
It is the "I don't know panther" which tirelessly models for me. I am debating what to do with him. Plastic surgery is expensive and there is not much left of the arm to put back together. So I may have to buy another (don't tell him that please -- he has enough to worry about). So donate what you can for both potential surgery and replacement costs using : https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
As dongles go, the Ztella is on the attractive side:
The cable has a nice jacket so hopefully lasts longer than the throw-away kind. Even the USB-C adapter is nice quality as you see in the picture.
I tested the Ztella on my Windows PC. There, typical of these dongles, the ASIO interface I use was truncating 24 bit audio to 16 bits. So for some of the tests, I used my Roon player in exclusive (WASAPI bit-exact) to avoid that issue. Note that this class of device also relies on the system device volume so be sure to check that.
Also, when I first plugged the unit in with a 33 ohm load, it reduced its output to half. This stayed so even after I plugged in a higher impedance load into it. I needed to unplug and plug it back in to get it to output the full voltage. This kind of behavior is typical of these dongles as they attempt to control the maximum power consumption.
In use the Ztella gets a bit warm which goes with the territory of higher power output it provides.
Audio Measurements
Here is our usual 1 kHz dashboard:
The best news here is 2 volt output as many dongles limit at 1 volt which severely reduces their power with high impedance headphones. On the down side we have a ton of noise spikes in the FFT spectrum (top right). This is likely system dependent and due to lack of sufficient filtering. There is just not much space in these dongles to put in proper filters. This may be the reason my measured performance is worse than the company's. And your phone may be more quiet than my desktop computer as well. As it is, SINAD falls in a region which is considered very good for dongles:
Even though I had to use the interface that truncates to 16 bits (and hence introduces some distortion), intermodulation distortion is quiet low:
Jitter performance is ugly because of the previously mentioned system noise bleeding through:
Again, most dongles are different shades of bad here.
Dynamic range is not as good as I like to see because of the noise issue:
Power Measurements
The problems above may not be audible. But what is guaranteed audible is lack of power so let's look at that using both 300 and 33 ohm loads:
I can predict with almost 100% accuracy that this level of power provides a very satisfying experience. And raises to almost top of our charts:
Output impedance is nicely low:
Headphone Amplifier Listening Tests
I only had time to listen using my Sennheiser HD-650 headphones. Here, performance was excellent. There was plenty of powerful and clean bass that was hard to imagine coming out of this little dongle. The only time I wished for a bit more power was with recordings that were not recorded loud.
Conclusions
The Zorloo Ztella MQA has good distortion measurements combined with lots of power in a tiny package. This results in very nice listening experience. Alas, the $99 price is quite high for a dongle. So unless something else is taken out, I would get the non-MQA standard version.
I am happy to recommend the Zorloo Ztella MQA headphone adapter.
------------
As always, questions, comments, recommendations, etc. are welcome.
Today is a sad day. Had my back to my photo stand and heard its backdrop fall down as it often does. Sadly this time it had a pink panther on it and poor "guy" lost its left arm as it hit the floor.