8
Sound Level
The linearity of human auditory perception is highly dependent of the sound pressure
level, and the range for optimal linearity is limited! We recommend a use of 83-86 dB
Sound Pressure Level (SPL) at the listening position. Staying in this range will ensure
you are able to make the right mixing decisions for a long period of time.
With these values you can’t go wrong! Mastering engineer Bob Katz recommends
working at 83 dB SPL (C-weighted, slow meter setting), calibrated using pink noise for
a single channel, 86 dB for stereo (stereo combined using uncorrelated pink noise).
And account for listening fatigue. Take a break when you feel the need to raise the
overall level. Rest assured, this is the right thing to do!
Fine Tuning and Room Adjustments
The listening environment usually has a big influence on the perceived sound quality.
Depending on the position of the speakers in the room and the properties of the
space a correction may be needed, and what do you know? We have just the thing!
On the back side of the cabinet you will find two knobs that allow you to optimize
the tuning of the Epic 4. Both trims cut or boost in a range of ±5 dB in 1 dB steps. The
HF-Trim starts above 2.5 kHz, the LF-Trim below 250 Hz.
In a bright sounding room, with many flat and solid surfaces, you may need less
treble. Use the HF-Trim-Knob (“High Frequency Tune”) to attenuate the HF range.
In a dark or boomy sounding environment, or if the listening distance is higher than
recommended, you can increase the HF component proportionally.
The LF-Trim (“Low Frequency Tune”) works in a similar fashion. It will usually be the
distance between the cabinets and the walls that necessitates a LF adjustment. The
original tuning was determined in a free (4Pi), anechoic environment with the knobs
in the middle position. Close to any wall this will change to a kind of boundary, 2Pi
arrangement with a LF boost. You can reduce this effect using the LF-Trim.
All the while maintaining excellent phase response!
Please do not exaggerate the level as this
can possibly damage your ears permanently!
!
