NuGen Audio - SEQ Series

If you are looking for a high quality, linear phase EQ with scaleable resolution, matching CPU to your context, then you need to try the SEQ series.


No phase warping Transparent sounding
No phase smearing Sharper transients

* Analogue shaped curves
* Quality that starts where many leave off
* Fully independent classic or mid-side stereo operation
* Linear phase operation
* Comprehensive global utility controls
* 64-bit signal path throughout
* Dual core optimised code
* All sample rates supported up to 192kHz
* Scaleable connective technology

SEQ1

7–band equalizer, offering fully parametric bell-curves, HPF, LPF, high & low shelving EQ and optional visual feedback.

SEQ2

Multi-band spline equalizer, offering a full range 10Hz to 30KHz spline envelope, HPF, LPF, high & low shelving EQ, and optional spectral analysis feedback.

SEQ3

8-Band stereo positioning equalizer.
Coming soon...

Why Linear Phase?

The NuGen Audio SEQ series, unlike many digital EQ’s, is linear phase. This means that the phase shift is linear across the frequency spectrum, resulting in a natural sounding EQ change, and producing minimal phase artefacts.

Traditional EQ algorithms employ a mathematical technique known as IIR (Infinite Impulse Response). Whilst this provides low CPU usage and is relatively simple from a mathematical point of view, there is an important side effect known as Phase Warping. Digital EQ utilising the classic the IIR approach distorts the relationship between frequency and phase.

The computational algorithm employed in SEQ1 is based up on FFT (Fast Fourier Transform Analysis). This is a much more involved process, involving transformation of the audio data into the frequency domain, before applying frequency related computations and then transforming back into the temporal domain. The advantage of this process is that the frequency and temporal relationship remains intact – linear phase transformation. The benefit of this method is that linear phase adjustments sound clearer, it is possible to create a much more transparent EQ using this technology. Phase Warping also affects the clarity of transients, as it causes Phase Smearing. Linear Phase calculations avoid this limitation, producing a sharper audio image.

Analogue curves

The SEQ series also features analoge shaped EQ curves for greater clarity and accuracy in the high frequencies.
The traditional approach to digital EQ has suffered from an inability to properly represent audio as the frequency approaches the top end of the usable spectrum (known as the Nyquist frequency). This leads to a warping of the expected natural EQ curve.

No-one told analogue EQ about the Nyquist frequency, so it doesn't take any notice of this limitation and produces symmetrical curves at any frequency. The SEQ series utilises algorithms that overcome this problem, producing analogue shaped symmetrical curves, even to the top of the frequency range.

Classic Digital EQ
The Bell curve distorts badly out of shape as the filter approaches the Nyquist frequency SEQ Series EQ
Analogue shaped symmetry is maintained


High Resolution

Another common problem - this time associated with linear phase FFT EQ - is a lack of resolution in the low frequencies. The SEQ series EQ's have the resolution you need at a scaleable factor suited to the task at hand - the only question is 'how much do you need?'. If you need it, crank the Quality setting all the way up - eg. during mastering - but if you don't, you can also choose to go easy on the CPU.

Narrow Q band EQ boost, frequency varies [white noise test]*
This real-world (no names) example shows how the SEQ filter maintains definition all the way down to 40Hz and below (blue trace) - well into the range where frequency roll off is common practice. The standard LP filter (red trace) looses shape and focus rapidly below 100 Hz, making precise adjustment very difficult.


High Sample Rates

Digital EQ can also suffer when it comes to higher sample rates. In the case of Classic Digital EQ, they are often not supported at all. Where they are, in a typical linear phase EQ, it can again be at the cost of resolution, particularly in the low frequencies.

Narrow Q band, EQ boost, sample rate varies [white noise test]*
Where as the SEQ filters (blue trace) perform well, it can clearly be seen that the typical LP filter (red trace) does not provide definition at higher sample rates, making it difficult to make precise adjustments, even at relatively modest frequencies.


Connective Technology

The SEQ series also boasts connective technology. This means that it is possible to link the quality settings of multiple instances together. This can be especially useful if you wish to use the same set-up for mixing and mixdown maximising CPU allocation for each phase of production, without having to change every plugin on every track. The quality setting for linked instances can be changed globally, simply by changing the setting on one instance. This means that you can easily save CPU when working with 'live' CPU intensive plugins, and then step it up to the max at mixdown - scaleable, connective technology. Of course, it is also possible to use individual instances at different settings, simply by deselecting the link option.

Price: $119 each.