Repro-1 (out now)

[wagtunes]

Hehehe, that isn't aliasing, that is the resonance still being there and locking in with the harmonics of the oscillators. People in the office also came over and said "Uh, it aliases like hell". Then I pressed a key on the Pro-One with same settings and "uh, ok".

OK so I've been wrong

It isn't aliasing as Urs has already exlpained here.

Hehehe, that isn't aliasing, that is the resonance still being there and locking in with the harmonics of the oscillators. People in the office also came over and said "Uh, it aliases like hell". Then I pressed a key on the Pro-One with same settings and "uh, ok".

[Urs]

It lacks bottom end authority of an analog, otherwise filters 2-5 all sounds really very nice and even 1 would be just fine. Volume differences between the filter models makes comparisons a bit iffy, and on most actually used settings differences between 2-5 are way too small to make any difference whatsover. At more extreme settings the differences become more obvious, but as the character of the filter is the same, I'd be tempted to say that the additional detail probably isn't worth the CPU hit. In the end the they all sounds like algos anyway, #5 was my favourite.

I agree to 100%

So you're saying we should give up?

[Urs]

Hehehe, that isn't aliasing, that is the resonance still being there and locking in with the harmonics of the oscillators. People in the office also came over and said "Uh, it aliases like hell". Then I pressed a key on the Pro-One with same settings and "uh, ok".

OK so I've been wrong

It isn't aliasing as Urs has already exlpained here.

There is still loads of aliasing though, it's just drowned in analogue artifacts. Settings can be utterly extreme, no 8x oversampling will fix that. No sure if we need to?

Also, this version I think still has a bug in the oscillators. It's work in progress, after all

[Vesius]

Well, I decided on 4. It keeps it's fizz the highest of all of them and exhibits the best behaviour when quickly feeding in a osc signal at high res. Mix signal affects the cutoff pitch on all of them which is a very nice touch indeed, but I found the way 4 behaved to be the most convincing, and by far the rudest that doesn't go into actual aliasing.

And for what it's worth, 1 does alias. The others, no.

[moscom_electronics]

[\rant on] Wow, I am amazed at the popularity of filter 5. This one is so boring! I think that the issue is that hearing the differences require that RePro be pushed into the realm of large modulations. It is really not enough just to make the filter ring with resonance to the maximum. Please play with OSC B -> Cutoff! Then change OSC B settings and play with the algos. The differences then are obvious! Again, 2 and 5 are really muting the sound when strongly modulated at high resonance level, they do no sound like possible candidates for the end product to me.... I would be really sad if they did I think that 1, 3 and 4 are way better options. Although I voted for 3, 1 and 4 have their strength... but damn, leave the dull 2 and 5 alone!!

Ok, [\rant off]

[Sound Author]

If Urs says it's not aliasing...then it's not #u@%!n& aliasing.

[chk071]

If Urs says it's not aliasing...then it's not #u@%!n& aliasing.

He just said it is.

I'm a bit confused though. I thought audio signals alias, not the filter.

[Sound Author]

I'm jk. As far as I know, there is no way to completely avoid aliasing. It's inevitable.

[Urs]

[\rant on] Wow, I am amazed at the popularity of filter 5. This one is so boring! I think that the issue is that hearing the differences require that RePro be pushed into the realm of large modulations. It is really not enough just to make the filter ring with resonance to the maximum. Please play with OSC B -> Cutoff! Then change OSC B settings and play with the algos. The differences then are obvious! Again, 2 and 5 are really muting the sound when strongly modulated at high resonance level, they do no sound like possible candidates for the end product to me.... I would be really sad if they did I think that 1, 3 and 4 are way better options. Although I voted for 3, 1 and 4 have their strength... but damn, leave the dull 2 and 5 alone!!

Ok, [\rant off]

Pssst, no worries, we do not feel obliged to use the poll result for the final version.

[Ivan_C]

There is still loads of aliasing though, it's just drowned in analogue artifacts. Settings can be utterly extreme, no 8x oversampling will fix that. No sure if we need to?

Also, this version I think still has a bug in the oscillators. It's work in progress, after all

I think there is an issue with the drone knob too, I get a strange sound on Reaper / W8.1 when I click on it without sending any MIDI note first (might be the default note being too low, a C4 might be better)

What I meant is I assumed that the "harshness" I have talked about in my message was due to some kind of aliasing. So I thought the "cleaner" filter models might be the closer to the original analog filter. But now I know that's not just aliasing but also something existing in the original filter, which means my guesses might be wrong... The "best" filter might be 2 or 3 or 4 or... I don't know anymore

And I have still not answered to the question "what is the filter I prefer" because I really don't know either...

[Urs]

I'm jk. As far as I know, there is no way to completely avoid aliasing. It's inevitable.

Yep!

[Urs]

And I have still not answered to the question "what is the filter I prefer" because I really don't know either...

Give it 3-5 days before you vote.

[Vesius]

chk071 - with no audio input, these filters are capable of generating an audio signal - that's why they are 'self-oscillating'. And that's why I'm damn sure Filter 1 aliases. At full resonance in the very high end with no modulation aliasing is really quite apparent on this model.

[Funkybot's Evil Twin]

It's interesting how a lot of pre-conceived notions about what a Pro-One (or any analog) filter should sound like are coming into play along with what is and is not aliasing. Yes, Urs said there's some aliasing, but he also said it's buried under all the artifacts (which means you're probably not hearing it). Several people have commented on how 5 is the smoothest and therefore is the most analog sounding, which I get, but it also seems overly polite and lifeless to me. I'd be very curious in hearing how Urs unit sounds at or near max resonance settings.

Urs, if I set both oscs to square waves (no PWM, no detuning, no mod), crank up the osc A+B volume to max (compensate on master), then jack up the resonance to 10, and set the cutoff just above 6 I get a popping type sound (not calling it a bug, but definitely a popping - maybe a bug in the oscillator, maybe an analog artifact). None of the other filter types exhibit this at all. There's also some very interesting little chirps when you really play with the osc volumes. Very quirky this one.

[chk071]

chk071 - with no audio input, these filters are capable of generating an audio signal - that's why they are 'self-oscillating'. And that's why I'm damn sure Filter 1 aliases. At full resonance in the very high end with no modulation aliasing is really quite apparent on this model.

You're right. But isn't it difficult to distinguish between "smear", or distortion with the filter self oscillation, and aliasing? I haven't tried RePro, but gathering from the sound demos, and other, similar synths, there's some heavy distortion going on in the filters, which leads to the pure (self oscillation) sine sounding more like a square anyway, right? I could be wrong, and tbh, i have no idea about aliasing anyway, because i never really tried it out myself, and pushed synths into areas where aliasing happens.