Heritage Audio 6673

Description

In March 1970 the first 1073 module was launched and became the standard in 80 series consoles. The 1066 was gradually replaced in newly shipped consoles and finally disappeared. The 1073 featured almost the same identical circuitry, being the most relevant differences the hi frequency shelving ( 12Khz instead of 10Khz ) and the equalizer´s mid band, which had one more center frequency, but lacked the constant Q of the 1066 . Vintage module connoisseurs do know how sweet the 1066mid band sounds and, for some, something was lost in the way. Until now…
The 6673 module is the answer to an old question among vintage module users. Should I use a 1073 or a 1066 for this specific source material? Should I need to boost at 700 Hz or would it be better to cut at 360 Hz? Should I need 12Khz or would it probably better to add 10Khz instead?
These and a lot more questions that have become “classic” in some professional environments have a new answer.

• 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 selectable frequency shelving at 10, 12 or 16 kHz, Baxandall type.
• Low Frequency: +/-16dB with selectable frequency shelving of 35Hz, 60Hz, 110Hz & 220Hz ,Baxandall type.
• 1073 Mid Frequency: +/-18dB peaking, fixed ‘Q’ , selectable center frequencies of 0.24 Khz, 0.36kHz, 0.53Khz, 0.7kHz, 1.1Khz, 1.6kHz, 3.2kHz, 4.8kHz , 7.2kHz and 10Khz , dual inductor based.
• 1066 Constant Q Mid Frequency: +/-18dB peaking, fixed ´Q´, selectable center frequencies of 0.7 Khz, 1.2 Khz, 2.4Khz, 3.6Khz, 7.0Khz, inductor based.
• High Pass Filter: 18dB per octave slope, switchable between 50Hz, 80Hz & 300Hz, inductor based. (Although push button switches has been used instead of the classic rotary switch, the circuit is the same exact one found in vintage 1073s, sacrificing only one frequency choice for space issues. Real state is tight on these modules).
• EQ Button: Switches the equalizer on or off.
• Phase Button: Flips phase 180º.
• 6673 Module available. 19″ Convertible format available Spring 2012.

Frequencies shown in orange indicate extra ones not found in the 1073 modules.

• Microphone input impedance: HI, 1200 Ohm minimum, LO, 300 Ohm minimum. Higher gain positions gradually have greater impedances, optimum for lo 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 1Khz, Less than 0.05% at 100Hz.
• Frequency response :20Hz (+0.3dB) to 20Khz (-0.2dB).
• Maximum Gain: Slightly greater than 80dB.
• Noise: Less than -100dBm.
• Power consumption: 110 mA @24VDC.

Additional information