The TUBE-TECH EM 1A Passive Tube EQ is an exact replica of our oldest "classic", the PE 1C all-tube, passive Program Equalizer, which itself is based on the classic PULTEC EQP 1A.
The EM 1A features an all-passive EQ section and a high quality op amp.
The circuit is in fact exactly the same as that of the PE 1C, only downsized to fit the modular form factor - without any changes whatsoever in specs or sound.
All the characteristics of the PE1C and all the famous special features are available.
All components, including all transformers are exact the same as in PE1C.
Due to the high quality of the TUBE-TECH RM Series power supply and the pristine audio circuits, the Modular Series products deliver exactly the same uncompromised sound quality as our 19" units.
EM1A Technical Description
The TUBE-TECH EM 1A is a passive tube equalizer.
The TUBE-TECH EM 1A Equalizer contains a low frequency boost and attenuation section (shelving), and a high frequency boost section (peaking). The high frequency section has variable bandwidth as well as attenuation (shelving). The filter section is of the passive type followed by a tube based push-pull amplifier to restore the gain.
Input and output are balanced as well as fully floating. Input and output transformers come with a static screen between the primary and secondary wirings
Tube based push-pull amplifier
Frequency response @ -3 dB: 5 Hz to 40 kHz
Low Noise: < -85 dBU @ 0 dB gain
CMRR: > 60 dB @ 10 kHz
4 low frequency boosts: 20, 30, 60 and 100 Hz (0 to +14 dB)
4 low frequency attenuations: 20, 30, 60 or 100 Hz (0 to -18 dB)
10 HF boosts with variable bandwidth: 1, 1.5, 2, 3, 4, 5, 8, 10, 12 and 16 kHz (0 to +18 dB w/ sharp Q, 0 to 10 dB w/ broad Q)
3 HF attenuations: 5, 10 and 20 kHz (0 to -18 dB)
Input impedance: 600
No insertion loss
Gold plated switches
Conductive plastic potentiometers
In- and output are transformer balanced and fully floating