As announced earlier this year, after the A20, which replaced a 25 W version of the Model A, we are going to release one more amplifier.
And two main, and closely associated features, distinguish the A21 from the A20: one is a higher power, and the other is a balanced topology.
Outside, the A21 shares a similar shape and look with the A20, however, it is physically bigger and more weighty (approx. 11 kg). Increased size and weight are normally a consequence of a notably higher power: the A21 is not only 100 W at 8 Ohm, but it also can provide 10 A, and thus drive somewhat lower loudspeakers impedances than A20 can.
Consequently, a more massive mains transformer was required for the output stage. This transformer provides separate secondary wingdings for two channels, so the output stage operates practically as dual mono. One additional, small transformer is used to feed the line-level circuits.
Inside the chassis, there are also many similarities with the A20, especially in the input switching circuit, volume control, and line-level circuits’ supply.
The A21 is however a balanced amplifier, and the essential for this feature is the input phase splitter. In the A21, this stage is a differential circuit without global feedback. It can accept either an unbalanced or balanced source, and output a balanced signal, which is then sent to the appropriate volume control, and then amplified by the balanced power amplifier stage.
The A21 employs three unbalanced RCA and two balanced XLR inputs. These two later inputs can also be used as unbalanced inputs, due to Neutrik XLR “Combo” connectors, which can also accept the phone jacks (the jacks are wired to accept both balanced and unbalanced signals).
Just like the A20, the A21 will also include a JFET buffered pre-out (RCA only), and Audial-made pure copper binding posts.
The A21 can be operated by the remote control, which will be available for purchase in the first quarter of 2022. The same remote control will work for both the A20 and A21.
Hi the Audial Team,
Please, send me a notification when the A21 is ready.
Best regards.
Marc BELOTTI
Hi Marc,
Thanks for your interest. We will do that.
We are about to finalize this design, but we are also checking the manufacturing feasibility related to the parts shortage.
Hopefully, we’ll come up with good news quickly.
When will it be ready?
Hows the snr measurements?
The idle noise is about 60 uV, which translates to something close to 100 dB at 1 W, taking into account balanced topology. This should be taken only as preliminary data, though.
Of course, when the time comes, we will publish definitive specifications.
Another update on the A21 release will follow in the first week of May.
We are going to postpone this release once again, this time hopefully for the last time.
The good news is that we managed to find some parts stocks which will make the A21 production feasible for now, or maybe even until the parts manufacturing and regular supplies stabilize (expectedly) in 2023. This will require small project changes – no compromises here, don’t worry, the point of all this is not to make compromises – so I will have to ask you for another month of patience.
It will be rewarded by significantly better A21 availability.
Thanks, and stay tuned, please.
Literally, my new reference solid-state integrated amplifier. As a reviewer of audio gear, it is essential to have a great tube amplifier as well as a solid-state amplifier to review a host of gear. One of our community members made me aware of Audial and spoke very highly of the A21. I was skeptical about how well it would keep up and perform alongside my Prima Luna Dialogue Premium KT88/120 integrated. I was instantly impressed by the A21’s ability to project into the room. The soundstage and imaging were superb, with a very sweet and clean upper frequency, a realness and detail to the mids and vocals, and very nice bass control. And that build quality and overall appearance is just mouth-watering!! I have clearly found my Prima Luna Partner… Well done.. 🙂
Thanks for writing, James. I am flattered.