i’d definately go for the “in addition to” option.
filter2’s cutoff really feels and acts odd and sometimes i am really longing for a “proper” one, but then again, oddness can sometimes come in very handy.
so a “filter3” device (or whatever it might be called?) in addition to the filter2 would be perfect.
Or we could just bring back the old filter device and add the options to it that are yet lacking… (filter1 was not gone actually but you have to save it in renoise 1.5 and load it in Renoise 1.9)
Its not that they lack something, they simply do not behave as you expect them to behave while not sounding “bad” (well, IMHO).
So, what do we actually want from the filters, aka what should be changed/added/fixed/whatever? Any concrete opinions, wishes?
The reason I don’t use Renoise’s filter is because the hipass doesn’t cut enough (or as expected). I tend to hipass every single sound to remove rumble and unnecessary low frequencies, and I find the current device unsuitable for this. I either end up layering a few filters in series, or I end up with leftover unwanted frequencies. For example, hipassing a kick with filter2 is usually not enough to stop it interfering with the sub.
The layering filters workaround prevents you from adjusting the sum cutoff frequency (and hearing the result in realtime), and it also attenuates frequencies around the cutoff too much unless you mess with the resonance… It’s just a bit awkward to do basic filtering.
Indeed, a set of ‘boring’ 12/24/36db hi and lo filters would be extremely useful.
The only problem i have with any of the filters is the highpass. It sound great for higher frequencies but i can’t get rid of the low end at all with it.
sorry i cant chip in on what to change/renew or modify,as im a new-coming renoise user(total-nOOb)so dont know the old renoise filters,but what about using the sonalksis(and other “standard”)filter types as reference and get the new filter(if you guys decide to make a new one)as close as those as possible??just an idea
(the time it took to write this,there had already been 4 more replys 
)
I’d like to be able to configure how quick the falloff is: (pic taken from here)
If it’s not possible to do that as a slider, then more presets (-12db, -24db, -48db, -96db).
I guess if the falloff is too step there will be artifacts? I don’t have much clue, but it seems that currently it’s not possible to really cut a frequency range off for good, at least not with a single filter instance.
The actual falloff of the frequency is rather artefact than a feature. To control it, you can add more “poles” to a filter. Some steeper filter algos cause some ripples, but Butterworth ones actually shouldn’t.
See more here:
http://en.wikipedia.org/wiki/Butterworth_filter
Ladspa plugins have a good quality configurable pole filters. And atleast by testing them with renoise internal spectrum analyzer they are very good and very very exact.
Check out: http://surnuaed.ee/ladspafilter.png (White noise, LPF @ 1kHz, HPF @ 500Hz).
The plugins are opensource, should give some ideas how to implement the algorithms.
Ripples? Artifacts? Sounds awesome… When can we get some? 
… I’d like to be able to amplify any artifacts too 
There are ladspa plugins implementing those algos, try them out. 
In all honesty, I’d like more bandpass options… I need to stack 4 band passes at the same frequency to get the effect I want… and I’d also like resonant filters that have more of an earthy squelch to them… not sure what would do this, but I’ve noticed that analog filters seem to pwn in this area, while digital filters tend to sound much too clinical.
Wow! I had no idea you could do this…I’ve forgotten what the 1.5 filters sound like now. Interesting…I’ll have to check this out.
I like the sound of the built-in filters, they are generally pretty handy. Sometimes I want something, yeah, a little grimier, more liquidy, organic, though. I miss my S550… 
You can just save the old effects in an effect chain in 1.5 and load it up in 1.9, the old effects are still in there, you just no longer can select them from the current effect-list.
i would say their accuracy
The code may be under GPL, but the algorithm itself isn’t. You get a idea how to implement the algos cleanly from there, not copy code.
So I don’t see any problem here.
I would still like to see some sort of Renoise API published so people could write their own scripts/plugins.
Ah, sorry, they were hosted on Fileden, but I forgot to renew my account and it expired
I think the description in my post is accurate enough though… Sorry, but I dont have the pictures.
Now that’s a nice idea 
OK, this is what I meant…
If I want to do a tight filter cut (which works like a bandpass), if I have the upper value and lower value of the filter in Renoise too close, it rolls down the overall level of the band.
This may just be a result of the graphical representation though (the gfx are small on the filter, after all) but I am not sure
Have a look at this screen dump for a visual example of that I mean.
In 3rd party eq plugs, this does not happen when the upper and lower values are so far apart.
Now if you look at the upper and lower cut values, they are about 500hz apart. This should not be causing things to dip down like this.
It does the same thing with Gliss EQ (because of the slope). However, you have to set the Q on Gliss to 2 rather than 1. Perhaps the Q settings on the Renoise shelving filters are labelled wrong?
it would be nice if the filter 2,would be able to go below 50hz
EDIT 
DOH just noticed that its already possible to go below 50hz.