I’ve not used a DN, so take this with a pinch of salt.
I doubt you can get some of the twangy, glassy, metalic or bell-like tones that FM is famous for out of an A4.
Overall, I find it “mid-forward”.
You can easily get buzzy, noisy, screachy sounds, and dry or sandy sounds. It’s “warm” the way an MS-20 is warm (i.e. a screaming banshee), but not the way a Moog or Prophet are warm (i.e. not an alluring siren).
It’s excellent for getting novel variations of classic analog sounds because the oscillators are “not quite normal”- all the core waveforms are slightly irregularly shaped, and all of them have pulseidth/tilt controls which do a lot to alter the harmonic content away from the standard balance. E.G. you have to turn the pulse-width control slightly off zero (5 or 6) to get a proper square wave.
Alongside this, the oacilator and filter controls are all very, acurate and detailed, and the oscillator drift control is optional. Taken together I find this makes it easy to get clean, bright, chip-tune noises from it. You have to get creative and disciplined to make it do more standard “warm” analog sounds out of it. The low polyphony count foces some workarounds which have an impact on the tone. E.G. you can make chords using the oscilators and sub-oscilators, but these all share their track’s filters, so they’re more like a paraphonic synth. It’s very useful towards the “one box” workflow, but it nudges your choices in certain directions.
If you pair it with other devices, you could make more use of multi-track polyphony and the voicing modes. This might get you closer to the rich Phophet/Oberheim type sounds. I havn’t tried.
I think it’s an amazing machine, but I pair mine with a Rytm. I think it pays dividends to consciously work to get each track’s sound significantly different; have them occupy different frequency bands (mix in the box). Consider dividing up the delay, chorus and reverb so that only one track uses one effect (to avoid mushing everything together). Then break all those rules occasionally.
(It does LOADS more besides: can be a filter bank, an effects unit, a drum machine, a CV sequencer & controller.
I sold my Phophet Rev2 and a Specral Audio monosynth when I got my A4. I occasionally miss the Rev2 (it’s a very different instrument), but I’ve been way, way more productive with the A4 than with the other two.