Cytomic "The Drop" Resonant Filter

[toothnclaw]

Over at gearslutz Andy said:

Good news people, in a break from working on the AAX stuff I've implemented a basic version of the OSCar State Variable Filter (SVF) and it sounds great so I'm going to include it in The Drop. I wanted to include an SVF in The Drop but previously tried the SEM 1-A SVF but found it way too clean so I dropped it.

How accurate is this OSCar-based filter? A 'basic version' somehow doesn't sound good to me. Will it be improved into a close emulation of the original before release?

[Funkybot's Evil Twin]

Over at gearslutz Andy said:

Good news people, in a break from working on the AAX stuff I've implemented a basic version of the OSCar State Variable Filter (SVF) and it sounds great so I'm going to include it in The Drop. I wanted to include an SVF in The Drop but previously tried the SEM 1-A SVF but found it way too clean so I dropped it.

How accurate is this OSCar-based filter? A 'basic version' somehow doesn't sound good to me. Will it be improved into a close emulation of the original before release?

There are samples earlier in this thread. Sounds damn good to me.

[andy-cytomic]

Over at gearslutz Andy said:

Good news people, in a break from working on the AAX stuff I've implemented a basic version of the OSCar State Variable Filter (SVF) and it sounds great so I'm going to include it in The Drop. I wanted to include an SVF in The Drop but previously tried the SEM 1-A SVF but found it way too clean so I dropped it.

How accurate is this OSCar-based filter? A 'basic version' somehow doesn't sound good to me. Will it be improved into a close emulation of the original before release?

It is very accurate. By basic I mean "very accurate and stupendously good sounding, but more cpu friendly". The only difference between the efficient version and the full version is modelling of the transistor buffers and more of the internals of the 13600 OTAs. If you aren't clipping the signal with huge signal levels at the input you won't notice much difference between the two versions. CPU usage for the efficient version is around the same as that of the current Sallen Key model.

[toothnclaw]

Great, thanks Andy!

[HamHat]

Please add a Japanese Filter Type, every one I have heard sounds amazing on the bass frequencies.

[andy-cytomic]

Please add a Japanese Filter Type, every one I have heard sounds amazing on the bass frequencies.

Can you please name some synths / filters you had in mind?

[HamHat]

The Japanese filter on Etch sounds amazing in the bass frequencies but the signal was always to colored when the filter was open all the way. Also on TB ReelBus when ever it was set to the Japanese mode the bass sounded wonderful as well, not sure if there would be a way to use that character as a filter type tho. Another great sounding filter imo is the Zebra 2 Analogue.

[knowix]

The Drop already has two "Japanese" filters...

I imagine one is modelled after the same one Etch's Japanese filter is based on...

[andy-cytomic]

The Japanese filter on Etch sounds amazing in the bass frequencies but the signal was always to colored when the filter was open all the way. Also on TB ReelBus when ever it was set to the Japanese mode the bass sounded wonderful as well, not sure if there would be a way to use that character as a filter type tho. Another great sounding filter imo is the Zebra 2 Analogue.

I'm of no use to help you out there since I have no idea what other plugins are doing, I model circuits, so if you have any particular synths or filter boxes in mind I can describe how they relate to what is in The Drop.

As pointed out by knowix, there are several Japanese resonant filter models already in The Drop. There are going to be three types of Sallen Key, and there are already two types of Cascade, which cover the two most prominent Japanese synth manufacturers Korg and Roland.

The Sallen Key filter circuits are based on those of the classic Korg MS20 synth, an efficient version, an MS20 mk1 version, and an MS20 mk2 version. The mk1 version uses biased transistors, the mk2 uses OTA chips. The original MS20 high pass filters are only one pole, but I've designed 2 pole versions of them. These models are very accurate, although I have made some slight modifications to make things fit better for The Drop. For instance in the MS20 mk2 they added a bass boost to the output buffer, I've left that off since I figure anyone can add a low shelf themselves.

The Cascade is based on the IR3109 filter chip used by Roland in lots of their classic synths including the Juno-6/60, SH-101, Jupiter-8 and more. I've picked the best parts of all these filters and made the Cascade filter from them.

Then there are going to be the Ladder PR (based on the Moog prodigy), and the State Var (based on the OSCar), so that is Japan, USA, and England covered!

[andy-cytomic]

PS: also when the filter is wide open I have designed The Drop to keep the original signal at the same volume and to be as clean as possible. Some drive is added, but if you set the resonance to around 15% you should be able to toggle the power button and not hear much difference at all, even without oversampling enabled. This is a very important part of making a professional resonant filter plugin to me since it is really useful to have this behaviour for breakdowns and buildups and other creative uses.

[HamHat]

PS: also when the filter is wide open I have designed The Drop to keep the original signal at the same volume and to be as clean as possible. Some drive is added, but if you set the resonance to around 15% you should be able to toggle the power button and not hear much difference at all, even without oversampling enabled. This is a very important part of making a professional resonant filter plugin to me since it is really useful to have this behaviour for breakdowns and buildups and other creative uses.

Best news ever! Thanks for the reply

[andy-cytomic]

]Best news ever! Thanks for the reply

I'm glad you appreciate this! It is very important to me too. There is a fully working trial version, why don't you give it a go and hear this for yourself? www.cytomic.com/drop

[HamHat]

Wow the Sallen Key is very transparent, very impressed. However I enjoy the sound of the Cascade SH a bit more especially in the bass frequencies, but it's not as transparent as Sallen when the filter is fully open. I automated the LP circuit to Sallen a beat before the peak and it sounds so good! All tho there is a tiny audiable blip because of the gap between filters, once that gap isn't there it will be the exact sound I've been looking for. Will be picking this up next paycheck, thanks for a great plug.

[andy-cytomic]

Wow the Sallen Key is very transparent, very impressed. However I enjoy the sound of the Cascade SH a bit more especially in the bass frequencies, but it's not as transparent as Sallen when the filter is fully open. I automated the LP circuit to Sallen a beat before the peak and it sounds so good! All tho there is a tiny audiable blip because of the gap between filters, once that gap isn't there it will be the exact sound I've been looking for. Will be picking this up next paycheck, thanks for a great plug.

Good to hear you like it!

I'm not sure I understood this completely, are you wanting to morph between filter circuits with a seamless transition? If so then that won't be included in The Drop as it would double the cpu load when changing circuit. I will be smoothing the LP and HP on / off power button transitions with a cross fade.

[Aloysius]

n/m