The 1084 module is considered by many to be a 1073 on steroids. It can be described as a 1073 with some added flexibility, without losing any of its many famous sounds.
The differences with the 1073 module are as follow:
3 selectable hi shelf frequencies, instead of the 12Khz fixed one in the 1073.
2 selectable Qs in the mid band, being the hi Q the same 1073 one.
5 frequency selectable passive LC Low Pass Filter, which is not available in the 1073.
The Low Pass Filter is especially useful for sweetening overhead tracks, harsh or brittle hi hats and cymbals. It also helps remove unwanted hiss and noise on bass heavy tracks, where a flat high frequency response is not needed.
In combination with the High Pass Filter, Special Effects can be archived, like telephone, radio and TV sounds that never sound natural using plug ins!
The Lo Q option in the mid band makes heavy boosting exceptionally natural and helps tracks sound unprocessed. Acoustic and classical recordings will highly benefit from this feature.
Whether you´re in doubt which module to choose, 1073 or 1084, and money is not the problem, the 1084 should be the way to go, as all the features and sounds of the 1073 are intact.
Whether you can live without the sweet Low Pass Filter and the 12Khz high shelving frequency limitation is enough for you, going the 1073 way might be enough.
80dB Class A Microphone preamplifier, HI-LO selectable minimum input impedance, balanced and floating. High gain positions show a higher impedance, ideal for old ribbon mics.
10dB Class A Line Amplifier, Bridging input impedance, balanced and floating.
Class A, single ended, 2N3055 driven high headroom output stage.
High Frequency: +/-16dB shelving at either 10, 12 or 16 kHz, Baxandall type.
Low Frequency: +/-16dB with selectable frequency shelving of 35Hz, 60Hz, 110Hz & 220Hz,Baxandall type.
Mid Frequency: Choice of 2 different 'Q' values with either +/-18dB or +/-16dB peaking, selectable center frequencies of 0.36kHz, 0.7kHz, 1.6kHz, 3.2kHz, 4.8kHz , and 7.2kHz , dual inductor based.
High Pass Filter: 18dB per octave slope, switchable between 45Hz, 70Hz , 160 Hz & 360Hz, inductor based.
Low Pass Filter: 18dB per octave slope, switchable between 6, 8, 10, 14 and 18 Khz, inductor based.
EQ Button: Switches the equalizer on or off.
Phase Button: Flips phase 180º.
Microphone input impedance: HI, 1200 Ohm minimum, LO, 300 Ohm minimum. Higher gain positions gradually have greater impedances, optimum for low gain ribbon mics. Input is transformer balanced and floating.
Line input impedance: 10KOhms bridging, transformer balanced and floating.
Output impedance: Less than 75 Ohms, transformer balanced and floating, to drive a load of 600 Ohms.
Maximum output: Greater than +26dBm into 600 Ohms, greater than +32dBu into 10KOhms.
THD: Less than 0.025% at 1 Khz, Less than 0.05% at 100Hz.
Frequency response: 20Hz (+0.3dB) to 20Khz (-0.2dB).