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Still no decent 303 emulations for iOS...
...with the exception of the ancient Technobox 2, which sounds authentic but lacks any sync options or IAA compatibility.
People still swear by Rebirth, but it always sounded plastic to me, and I already own the clunky, (now abandoned) iPhone version.
As for Bassline...it really sounds very little like a 303. There are occasional similarities but it's pretty much a different synth in its own right.
So.....am I missing something obvious? The only other emulation I'm aware of is for Tabletop. Is there a good 303 app that I should be aware of?

Comments
Rhythm Studio by Pulse Code, Inc.
https://appsto.re/gb/ZfqfB.i
Claims to have a 303 emulation in it. I can't say if it's a good one though as I have never heard an original one.
Many have tried
There even a 1111 (303+808) by Alexander Smith. Not terrible. Technobox 2 is a tasty one for sure.
Rhythm Studio is a big box of great sounds- Rebirth to my ears is pretty great, maybe outboard EQ and Compression? Chicago inside Gadget has that bite...I've only heard the original on recordings, mastered at that, so take my advice for what it's worth (2¢ at best)
Another route is using a fully fledged synth, there's a few formidable options for programming, vintage emulations like Model 15, iMS-20 etc Pulsecode's Modular has a good acid patch...
Some gifted members may have some programming tips and synth ideas...
There was/is an xoxbox app available in the US store- but I don't know how good it is- it looks and sounds ok in the YouTube video. But yes I agree- I actually made a post like this some time ago. There is no decent 303 app out there. I have a Roland TB3 which is an absolutely superb piece of kit and well worth the investment if you can stretch to it.
I've played a Roland 303 back to back with my Phoscyon, the square wave was so close I couldn't tell which was which, the saw wave failed and I could hear the difference a lot.
Among a few others I really wish d16 ported some of their stuff to us...the Technobox 2 dev, Audiorealism, makes a top rated VSTi 303/semi-modular, ABL Pro, as well as ABL.
Caustc ...maybe?
No - nice synth but no 303 IMHO. The version in the beta (will 3.2 ever be released?) is pretty cool in that you can draw your own waveforms. Gives it a lot more flexibility. But I don't think there's anything better than Technobox or Rebirth. I wish the Technobox guys would come out with a standalone 303.
New sounds maybe! Just kidding sorry, disregard.
afaik the original 303's filter is a regular 24dB 4-pole design, but something went wrong in developement and the last pole doesn't work as intendend and distorts.
So it's generally considered an 18dB filter plus X... the bug that became a feature.
cheers, Tom
for 303 sounds..................
like the good old Rebirth! this into WoW FX is SICK!
I do not despise Rebirth so much. And sounds can be processed through efxs, too
That BassLine that goes with MoDrum looks somehow close to 303 to me
Seeing as Technobox seems to be built off Audiorealism's excellent ABL2 (still my favourite 303 VST... I never really liked Phoscyon), I don't know why they don't just port that.
I'm reliably informed that Roland are working on a Boutique 303...if it's as authentic as the JU-06 was to the Juno 106, I might just wait it out for that.
Why use an app when there are also free browserbased 303 emulators*
To name but one:
http://errozero.co.uk/acid-machine/
*of course no audiobus, iaa, au, etc. but still it's free
Hang on there. What do you imagine is conveyed by a “pole” in a filter, and how might such a filter pole distort, from a technical perspective?
Might as well stick to Technobox 2 if I'm going down that route;)
(simplified and leaving math aside) the Moog ladder (filter) gives a good impression:
each of it's 4 transistor pairs represents one 6dB filter stage, which increases the steepness of response to 24 dB after the signal passed the last stage (6, 12, 18, 24)
'Pole' originally refers to a math term, which in this case happens to coincide with the physical filter stage.
iirc there was a misprint (false calculation ?) on the TB303 circuit diagrams used during production.
So active parts (transistors) were not driven as intended.
Distortion may habe a lot of forms, it's not necesarily a fuzz like tone.
cheers, Tom
Oooh
with a piano roll!
I would pay 30 € for a full midi and Link version of this one...
http://www.acidvoice.com/avalon-bassline-synth.htm
Chicago in Gadget is clearly based on the 303, can't really say how close it sounds, I'm afraid I was never a fan of it.
perky offer...
it has USB midi, tho - nice sound examples in the A/B comparison, cool
cheers, Tom
The problem with Chicago is that it's missing the 303 slide/accent. Caustic has these features built into the sequencer. I hope Korg one day adds them.
Peace \/
chisel316
Cool story @Telefunky, never knew about it.
Having dedicate accent and glide buttons on the sequencer sure is handy but both can be programmed in Gadget. Automate the glide control (draw it high on the step to turn it 'on') and use velocity for accent.
I don't really 303 much these days but fondly remember the Rubber Duck as the best emulation ever.
Hate to say it in mixed co. but tabletop's x0x is tasty...
Over the year that I've had my iPad mini 4, I've tried my hand at some 303-ish Acid songs.
Using Caustic:
Using ReBirth:
Using Gadget:
Enjoy!
chisel316
Nice....
Yup.
One of the tricky aspects of 303 emulation has nothing to do with the synth at all, but rather, the sequencer. The slide is not exactly like a portamento, although they fulfil the same purpose.
On a conventional synth keyboard with portamento, the time constant (the time it takes to complete the curve) is a fixed gradient of whatever you set it to, and will aim to complete the slope in its own good time contingent upon whether you’ve finished transitioning from one key to another.
If you lift portamento up to a mid value, then press a low note and then the next note up, quite quickly, it’ll not quite reach it, but if you press a low note then the next note up and hold the note to give it enough time, it’ll reach it.
If you press a low note and a high note, the same applies, but it’ll require longer to complete the curve.
The curve angle is about the same no matter where it is applied. Hence, a wider note interval needs more time. Also, the portamento starts from the hit of the first note and continues until it decides it is finished sometime during the second note. (This varies depending on legato mode of some synths – some will require a second note onset during the first, or it won’t do portamento to the subsequent).
On the 303 sequencer the glide is different in two aspects:
it doesn’t start when the second note is hit, instead it actually finishes when that second note is hit. It can do this because it is a sequencer, not a live keyboard, hence no extra sensory perception or premonition is required by the synth to guess if you’re going to glide from one note to another, it already knows it is going to happen, it is written, in the sequence data.
The other aspect is quite strange, in that it is a constant time, not constant gradient. The time to glide is the same no matter whether it is a note and the neighbouring note, or a note and a quite widely separated note – it takes the same duration in time, therefore the slope will have to become the variable.
Here's a track i made with abl3 by audiorealism. Would be amazing if they ported it to iOS
https://m.soundcloud.com/mireko/acidlick
The above Gadet examples get close to the tone of the 303 but, crucially, lack the unique glide and accent that are what defines its sound. That's why, as previously mentioned, the sequencer is an essential part of it.