Cabinet Simulator Producing Dc Offset

I’ve found that using the Cabinet Simulator effect often produces a DC offset in the signal, which can take up lots of room in the mix making it feel dull, drowning out the more subtle sounds. It obviously affects gating and keeps the compressor(s) busy.

Anyway, to reproduce it, load up the Sine.xrni chipsound, stick a Cabinet Simulator in the DSP chain set to Ventral, play a C-4 and watch the scopes. For me at least, the signal is pushed downwards. I’ve been working around this by sticking a Butterworth 8n HP filter @ 0kHz after any Cabinet Simulators, which gives me more space for plinky-plunky sounds next to meaty beats. :)

The problem appears to be exacerbated by higher playback sample rates.

The actual Renoise Cabinet Simulator has its pros and cons. The best thing with this simulator, is that it gives a true personnality to some digital-type sounds. On the other side, (even if it can be discussed but) I think that it naturally boosts low and high freqs. And if the incoming signal isn’t properly treated at first, you’ll get small unwanted side effects. Just try to add in your track dsp chain a EQ10 device BEFORE a Cabinet Simulator, and build something like a Gauss-type curve, lowering low frequencies and high frequencies. Globally when playing with parameters, you’ll find less unwanted side effects.

Thanks for the reply Kurtz. I’ve been playing around with treating the input signal as you suggest (and using different samples), but I still find it easy to end up with a significant negative offset in the signal. I don’t particularly want to remove the extreme frequencies - I like the effect the Cabinet Simulator produces, it’s just taking up more room in the mix than I’d like! :) As I said, adding a filter after it seems to correct the problem without affecting the actual sound too much.

The fact that it’s affected by the playback sample rate makes me think it’s a bug. I’ve also found (probably unsurprisingly) that adding reverb later on in the DSP chain really compounds the problem, although it can be reduced by setting the reverb low gain to be negative.

I got a similar result.

Add the DC Offset DSP after Cab and tick Auto DC on that to fix it.

With Reverb DSP’s you usually want to kill off very low ranges, using the Filter DSP or an EQ. I find the Filter DSP very handy for that task, using a high pass filter with the Butterworth 8n Model, depending on what you’re doing of course.

So try: EQ -> Cab -> DC -> Filter -> Reverb.

I’ve just re-checked deeper my own xrns projects, to see how I’ve worked it out… and realised that you’re right.

Each time I used a Cabinet Simulator, there is not only a Mixer EQ with a Gauss curve BEFORE the Cabinet Simulator DSP, but also a small mpReverb AFTER.

… in all my tracks, all my songs…

Yeah, I tried auto DC and it fixes it with no audible difference, although my personal preference is still the filter since it responds quicker (useful when the input is choppy, such as beats). You’re right about the reverb. I’ve been using the filter on the mpReverb itself since I still want the low frequencies to be passed through dry, unless there’s a better way?

I guess when you’ve found a sound you like, you subconsciously repeat it? I’m pretty sure I do.

You can still keep the low freqs, just filter/eq it gently :)