Filter and MIRx

[Jan1981]

Hello,

I have 2 different questions concerning the VIPro.

First, I would like to know, how you guys use the filter-feature - or maybe someone of the developers could tell me, what it was designed for; what you had in mind. At the moment, I am using it in Mixing automation - combined with slight MIRx-dry/wet changes to achieve diversity and make space for other instruments at certain points.

This brings me to my second question. I do not completly understand the concept of MIR(x) or of IR/Convolution-stuff in General. And maybe it is not necessary, but some practical things confuses me a bit. For example the routing inside VIPro. When I apply MIRx and then I change the Overall-Volume-fader, what is the effect? I mean, is the volume increased before MIRx in the chain? Does the chain even have an effect on this matter? The thing is, I have the feeling, that when lowering the Overall-Volume, the instrument sounds not only quieter but also more lost inside the room. And what does "natural volume" do? Where does it interveine?

Thanks a lot!

Jan

[Dietz]

Hi Jan,

sorry, but I _have_ to ask this seemingly unfriendly question (... but rest assured that it's not meant this way): Have you seen MIRx' Manual already?  Most of your questions should be answered there, e.g. on p. 11 ff.:

@Another User said:

NATURAL VOLUME 

 

Each instrument in a symphonic orchestra has a specific volume, with the Percussion section (Bass Drum, Piatti, TamTam) being the loudest section. 

Natural Volume (1) takes these individual volume levels (2) into account, always referring to the loudest possible sound the instrument can produce. 

 

> If you are writing for a full orchestra with full dynamics (ppp to fff), Natural Volume will provide you with a great starting point for your mix. 

 

> Natural Volume will also help to adjust the relations between instruments quickly. 

 

> E.g., if your loudest instrument is at a Natural Volume level of -10dB (Vienna Horn): 

 

1) you can set this instrument at 0dB in your mixer 

2) and add 10 dB to the natural volume value of all other instruments. 

 

> If you are writing a very quiet piece, you can raise the levels accordingly! 

 

> A Natural Volume Overview for all instruments can be found at the end of this manual. 

 

 

 

PRE-EQ 

 

We have matched the best positions for each instrument and section in every MIRx Venue with carefully tuned Equalizer Settings. 

 

> The Pre-Reverb Equalization adds to the virtual representation of your instrument and tames potentially problematic frequencies that result from the architecture of the selected hall. 

 

> Additionally, the Pre-EQ also plays quite a big role in character presets such as the Solo Strings Presets! 

 

> Try deactivating the Pre-EQ with a few presets, to hear the difference! 

 

> As an alternative, you can also use the built-in 

 

 

 

... and Vienna Instrument's output volume will of course affect MIRx' output, too, but it should not affect the dry/wat ratio. Remember that our ears are highly non-linears tools, which means that our perception of a signal changes significantly at different volumes. 😊 

 

Kind regards,

 

[Jan1981]

Thanks for the fast reply, Dietz.

In fact, I have read this already. The thing is just, that I really think, that I do not understand, what might be everyday-stuff for you. Maybe it has to do with my false understanding of how MIR(x) works, so I try to explain, how I think about it and you can correct me.

I imagine a certain space (maybe a church or something) and there, at a certain spot, I let a sound play. When I now increase the volume of this certain sound inside the church, it sounds different, than normalizing the mixed dry/wet signal afterwards. And somehow I believe, that MIR(x) works similar, but I am not sure, if it really does. So in my understanding, it would make a difference, where the Volume-Fader is set inside the chain. If it is applied before the Reverb it would have a different Outcome, than when applied afterwards. Or to take another example: If I put a speaker inside a church with a recorded cello and I let this play much louder than a normal cello would be, it would sound unnatural. The more I think about it, the more I have the feeling, that I have a wrong understanding of what IRs are. For example in my head, the Expression is set before the reverb and the Volume afterwards. But I do not really know, where I got this from. If this topic is too big, could you maybe give me a hint, where I could read more about IR and convolution. I have read some stuff from Beat Kaufmann already (which was really helpful) and all around the Internet. But maybe, you know something more (I will reread it in the manuals anyway). Thanks a lot in advance.

Jan

PS: Concerning the filter, I know what it does technically, I was just interested, how people use it. For example, when playing live, I have it on the same CC as V-Xfade and Expression, because it makes the getting quieter of an instrument more "round" (I dont know, how to explain this in english).

[Dietz]

Hi Jan,

several hours ago I wrote a nice, lengthy reply to your message - but then my browser decided to delete the text instead of posting it. *grrrrr*  … my second (and late) answer will be shorter, therefore.

@Another User said:

The more I think about it, the more I have the feeling, that I have a wrong understanding of what IRs are.

I tried to cover the basic idea of impulse responses and their use in MIR's convolution engines in a little add-on to MIR Pro’s manual. It’s called “Think MIR!”, and of course all the aspects I mention there are also valid for MIRx. You can download it here.

HTH,

[Jan1981]

Thanks a lot, Dietz! Your ThinkMIR looks great. I will read it in the next days. :-)

[Paul McGraw]

I understand what the filter does, but I was hoping for some ideas regarding when to USE the filter in musical context? Please give some examples of when one would want to use the filter to cut high frequency content.

Several things occur to me as possibilities, but I could be totally wrong. For example, if you are writing a cornet solo and you want a slightly darker tone for aesthetic reasons. Would that be a good example?

Or is the full orchestra is playing, and some instruments are obscuring others because of high frequency overtones. For example, perhaps cutting high frequencies using the filter on cello and bass and viola so that the woodwinds could be better heard? But that doesn't seem very realistic. 

I am still learning about mixing and mastering concepts so examples would really help.

[Dietz]

I think it is important to differentiate between a filter and an equalizer.

A "filter" usually describes a device which cuts frequency ranges above or below a certain corner freqency, at a certain "steepness": These are low- or highpass filters (a.k.a. hi-cut and lo-cut). In other cases the filter is used to inbetween or outside two corner frequencies: Band-reject (or notch) and band-pass filters.

An equalizer (EQ) is a close relative to a filter, but not the same. A single EQ band is able to quiet or to amplify a certain frequency range, but its hardly meant (or able!) to cut that range completely. 

What you seem to refer to is the low-pass filter of VI Pro, not the built-in EQ - did I get that right? Personally I wouldn't choose a filter as primary tool for most mixing tasks as it is rather meant to be used for (mostly dynamic) sound sculpting purposes. Static EQs would be my first choice. 

... but as I wrote above: The border between EQs and filters is blurry, and it might happen that a certain situations asks for radical changes, not just for slight adjustments. In those cases, hard filtering might fit your needs perfectly!

HTH,

[Paul McGraw]

Thianks Dietz. You are correct that I was refering to the Filter control in the VI Pro "Performance" section. So I guess it better to just ignore that parameter.

[Dietz]

For mixing there are tools that will cover your needs better than a simple low-pass filter, that's for sure.

... but don't underestimate the power of a dynamic filter for shaping the performance of an instrument in real-time.

Kind regards,