Pre-processing EQ

Hi vitaliistep,

there's a good example in the manual,

13.5 Tutorial 5: difference between spectrum profile and equalizer which gets to the heart of this question.

In essence the engine has it's own reactive life, sitting there mathematically waiting until we interrupt with our keyboards and other input like the pre EQ - then it sings.

The engine among other things works with fundamentals and overtones (related but worth more reading).

The Spectrum profile affects each fundamental (up or down) as it relates to other spectra in real time.

The EQ pre-shapes the fundamentals' balances, dialed up on the interface before it hits the engine - so like a band or as many tiny bands as you want can be given powerful influence without radical volume consequences (like you get with regular EQ in post).

But that's dry wording - there's probably way more going on - how to describe? Here's how I think as I edit presets..

So, maybe a plain way to think of it is the EQ (button on the main interface) sends parameters which shapes the data fed into the engine. In hard experiential terms, you can hear a radical EQ change without blowing our speakers or ears.

This is unlike say an EQ where you can lower all bands and it's volume = 0 - or raise all bands and volume = deaf forever (also note a flat line anywhere = same dB no change - good anchor point to grasp it I think - it only acts on our chosen dips and peaks - so you can really influence just one note, if you want). Balance happens because, this EQ, in effect (if not technically accurate to say) only tells the model initial fundamental related EQ numbers, nothing about volume other than balancing (not sure of course of the kind of maths/science going on there in the background but might be linearly aligned to some dB related algorithm). So if you kind of get this, it's extremely 'plastic' in the good sense of the term.

In the middle, the engine does its thing calculating auto-magically on the fly, then outputting our results impacted by our initial EQ shaping.

On the end of the chain, you could then apply EQ3 (3band parametric with Qfactor) and blow as many speakers as we want

Interestingly, when you add "Spectrum Profile" editing into the middle of this - you can nudge and diminish 'bands' in respect of how the overtones all interact! or really boss them about - adding, subtracting and balancing overtones - it truly seems infinite and part of the real magic, that you can experiment quite dramatically and still find a way to the sounds your looking for.

Playing around with these, without fear of breaking something is recommended. Push the things too far and then peddle back until you really hear what's happening.

Anything I'm badly misunderstanding? Corrections always very welcome.

Hey bm,

definitely saw another thread about below 60Hz audio and the EQ.

Quick search..

Philippe mentions it here

The quote, for convenience..

There are some really interesting explorations into audio from all angles across this forum and always great to find out more about the evolution of Pianoteq.

In the end, probably for most, it's what happens in the air between the speakers and the ears which tells the meaning of the whole story in full

Yeah! that's a great way of looking at it dazric. Almost like you can take the piano, make the cabinet thinner or thicker with that pre EQ and other goals, then mic it up and so on. It does seem to make other things you alter in the interface reactive to the initial EQ.

Fun-est subtle things to look at with the pre EQ might be slopes like you mention across the whole range (if a piano feels too bassy or toppy on your system) it's a very simple and pretty safe cure.. or let's say you have a piece where you play a melody across an octave above C1.. you can really target that octave alone if it suits your recording.

Try finding the range (or even single notes) by ear and reduce/extend to fit (I actually haven't got myself an exacting chart or something else like it for this which might be a cool tool to find or make maybe).

With three dots, raise the middle one to create a peak. Move the dots wider until all your intended notes are given the level of clarity you want - or lower reduce sparkle. Artistically, it's limitless to go after our intended aims.

With the parametric EQU3 I'd always recommend getting into its Q factor settings - you can really squeeze some interesting (or outrageous) frequencies together or lift them out here - or go very subtle. Sometimes you can raise a range in the pre-EQ to allow more timbre into the engine, then temper it at the other end with EQ3. Or try accelerating a range by upping both ends even a little

Nice quick thing to try - if you want to remove say, a 'ring' or 'boom' somewhere you might find the frequency by upping the Q factor to near 100 (low numbers are like the tide, carry a lot of range - high numbers give you a laser pointer) and dragging the points around (you might get old shortwave radio sounds as you drag) and note the frequency or frequencies you do or don't like - then enter those nubers in the pre EQ to raise and lower very targeted things.

Last thing before I go re: EQU3 being a broad brush - it can be surprisingly targeted and pointy even without raising Q. I still can't get over "Grand Piano Enhancer" setting in EQU3 - I find those freqency points are really nice to work from, tending to drop them, it's just amazing to me how present this is. Actually very thankful to Modartt for that - I was looking for those - really helped.

Oh, just one more really worthwhile thing before I forget - lots of mention about lowering the 7th overtone in Spectrum Profile (I used to overdo that) - maybe another area a bit like this, which can also help our preset tweaking but via EQ directly, unrelated to only piano BTW: Try sculpting down frequencies a little at around 500 Hz - short expl. = less muddiness magic possible for no-brainer effort - at least a great range to start with if sound feels cluttered.