Bass / Treble; Loudness - RME Audio ADI-2 Pro User Manual

This is one of the many major features that can't be found on any similar device: a high-quality
5-band parametric EQ, usable at up to 768 kHz sample rate, easy to set up and adjust, with a
graphical display showing the resulting curve, and multiple storage places including individual
naming. So whatever EQ setting you need, it is loaded and modified quickly. And there is not
only one, but three such EQs, separately for the analog inputs, and both stereo analog outputs.
On a related topic: These days many people suffer from hearing loss in varying degrees. No
matter if it is biological, from abuse or an accident - hearing impaired is a plague of modern
times. And – no surprise when thinking about it – it never affects both ears identically. The num-
ber of people having one sided hearing problems is huge, but they have learned to live with an
industry that totally ignores them. Although the solution is as simple as logical – have the EQ be
adjustable independently for left and right. Basically digital EQs are calculated this way, the
common controls are just for making it easier to operate. The ADI-2 Pro includes an option
called Dual EQ – a heaven send feature for many, for sure.
Of course a 5-band parametric EQ is also suitable for speaker and room correction, another
application where separate EQ left/right setups are necessary. Using the ADI-2 Pro as DAC for
the main monitors will benefit from this and all the other typical RME features available on all
analog I/Os: Phase and Mono in various options, Width and M/S Processing.

8.4 Bass / Treble

The simpler form of EQ has been the Bass and Treble controls as they are found on any 'stan-
dard' HiFi stereo amplifier. They easily and quickly allow to modify the sound to your personal
liking (more or less Bass, more or less Treble, obviously). An even more useful application is to
quickly change the amount of Bass / Treble in smaller quantities so that music compilations
don't have one song making the cones fall out while another one makes you think that really
happened. Producers and mastering engineers not only have their own taste, they also some-
times fail in providing a mix that is on an average sound level compared to others. In that mo-
ment a quick turn on the two ADI-2 Pro's small encoders will make the music sound perfect.
These Bass and Treble controls are limited to ± 6 dB. Everything exceeding such values should
be handled by the EQ, and/or calls for better speakers/phones. The corner frequency and qual-
ity factor of Bass and Treble is user-adjustable in the display's menu, making this feature even
more useful. Adapt it to meet your speakers/phones or your personal taste – it will greatly im-
prove your pleasure in listening to music again.

8.5 Loudness

Another legacy of HiFi amplifiers: there has not been a single one missing a feature called
Loudness. It tries to address the changes in frequency-dependent hearing sensitivity over dif-
ferent volume levels. If one listens to music loud, then drops the level by at least 20 dB, sound
loses punch and glitter. HiFi amps tried to fight this effect by adding more bass and treble the
lower the volume was set. Unfortunately that never worked as intended, and just became an
additional bass/treble booster. Reason: the manufacturer of the HiFi amp could not know what
volume any position of the volume knob equals at the customer's home. Room size, room
dampening and efficiency of the used speakers are all unknown.
But the effect of loss in perceived sound exists (read about the Fletcher-Munson curves), and
can be easily reproduced with any serious gear by comparing normal volume and DIM state
(usually -20 dB). The ADI-2 Pro offers Loudness for both analog stereo outputs, and most
probably it is the first time ever that Loudness works as intended. The user can decide how
much maximum gain in Bass and Treble should occur at lower volume settings. The user also
sets the Low Vol Reference, where maximum gain is achieved. After extensive tests a 20 dB
range has been defined as range for maximum gain to no gain while increasing volume. That
seemed to be the perfect definition of the range that needs to be addressed by Loudness.
User's Guide ADI-2 Pro © RME
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