i don't doubt that.. had the same experience with recording my pro one. why shouldn't a human be perceptive enough to pick up on subtle stuff like the difference between oscillations?
each analog circuit has it's own way of producing the waveform you hear.. it's not like perfect math jsut ocmes naturally in electronics. there are little ways of doing stuff to reduce the 'peak' that comes in at the start of when a pulse wave switches.. leveling out oscillations and stuff i don't understand at all.. tons of stuff on it on the web. yer basic low-parts-count referred-to-as-a 'pulse' osc has a load of shrinking teeth along the edge from whanging that current back and forth. it's an edgy sound i am familiar with (you too if you remember my homemade box.)
in other words, it's a buggery job trying to get a perfect sawtooth ramp. designers have different ways of applying circuitry (ie. there is no perfect way afaik) to approximate this ideal form, and each way is going to produce it's own, unique timbre, of ocurse.
now in virtual form, drawing a straight line is easy.. the only thing you've got to deal with is your digital resolution, which is a new sound altogether.
so on about my z again.. it's got 4 lfos right and i've been doing these analog emulations with layered (say one at 5Hz and one at 14Hz) 'random vector' lfo waveforms (it generates a positive random vector and a negative one for eahc cycle.. like two straight lines, but the angle to be determined) and it's just so right on analog. you know when the sound comes out of an analog and it's so colourful you can taste berries.. it gets there.. really sounding vivid and alive like analog where the self-oscillating resonance licks around your head like a hallucinatory salamander. my filter sweeps go thru my fucked up warbling oscillators like 'ooh glitchy dirty potentiometer..' sounds so lovely..
i think i'm kinda liking it more than real analog because it's so clean, but it's a bit starchy to set all the variations personally.. to ramp the scale just so.. just a little flat on the highs.. ie. ooh, i'll pitch this one down, offset it one 3Hz.. sorta silly when there's one that's 'messed up' naturally.
16, 32, 1024 random vector modulators should be even better, to apply in seperate layers (ie. a fast and a slow random vector and maybe another pair subtly altering the speed of each..) to envelope times, et c. my envelopes are sounding bit stiff now that i've got the oscillators coloured up. the bass doesn't seem as thick either but that's probably largely idiomatic.
cos in analog, you've got all these things that are affecting your waveform.. the circuit design, down to temperature, dare i say planetary magnetic fields and cthulhu and stuff.
but why not just-as-peachy??? it's not like there are digital speaker cones and digital air (hope not anyway) so eventually the sound has to go analog somewhere.
maybe one day there'll be a v.a. with presets designed to emulate an analog played on neptune, or by kilo, since we have magnetic fields too. subtle, but there's your variation and magic.
when i finish this track (riight..) i'm also sampling some 'raw' oscillator (for making a point elsewhere) if anyone wants to look forward to it. it's sweet!