User manual MILLENNIA STT1

[. . . ] 5 INTRODUCTION (see block diagram) The STT-1 Origin is a collection of Millennia's essential product line combined into one box. The STT-1 is a single channel (mono) processing chain with various signal path topologies (vacuum tubes, discrete transistors, audio transformer, transformerless) all selectable at various functions. The STT-1 offers an entirely discrete, entirely Class-A direct signal path from input to output. The signal path can be variously selected to use vacuum tubes or transistors, transformer or non-transformer coupling. [. . . ] When Line Input is used, it is recommended that this Gain Control remain fully CCW with the Output Master Level control set between 12 o'clock and 3 o'clock as a starting point. If additional gain is required for line level signals (such as unbalanced "-10" signals), raise the level using use the Vacuum Tube Gain Control. Line level signals sound fantastic in the Origin, but for optimized performance of EQ and Compressor with line level sources, the stand-alone NSEQ-2 and TCL-2 Twincom stereo products offer slightly improved specifications. This is due to the additional (and required) interface circuitry found in the Origin. NOTE: We did not attempt to unify the rotational position or resolutions of the SS and VT gain controls. That is, the user cannot place each gain potentiometer at the same angular setting and expect the same gain. Rather, we have optimized each gain amplifier unto itself, not in relation to the other gain amplifier. (7) SOLID STATE GAIN CONTROL "SOLID STATE GAIN" A potentiometer which offers a front-end solid state gain range of 40 dB, being an absolute gain range of approximately +10 dB to +50 dB at the direct balanced output. When Line Input is used, it is recommended that this Gain Control remain fully CCW with the Output Master Level control set between 10 o'clock and 2 o'clock as a starting point. If additional gain is required for line level signals, raise the level using use the Gain Control. Line level signals sound fantastic in the Origin, but for optimized performance of EQ and Compressor with line level sources, the stand-alone NSEQ-2 and TCL-2 Twincom stereo products offer slightly improved specifications. This is due to the additional (and required) interface circuitry found in the Origin. NOTE: We did not attempt to unify the rotational position or resolutions of the SS and VT gain controls. That is, the user cannot place each gain potentiometer at the same angular setting and expect the same gain. Rather, we have optimized each gain amplifier unto itself, not in relation to the other gain amplifier. NOTE: An approximate 20 dB of additional solid state gain is available if necessary. Contact Millennia for customization information. (8) SOURCE SELECT SWITCH "SOURCE: MIC - LINE - DI" Rotary switch (Grayhill, military-spec, gold plated) which selects the front-end input source as either microphone, line level, or 1/4" DI (instrument, keyboard, etc. ). Mic, Line, and DI inputs all feed the same front-end amplifiers (selectable via switches as either vacuum tube or solid state, transformer-coupled or transformerless). When used as a solid state amplifier, the circuit is essentially identical to the front-end found on Millennia's acclaimed HV-3. When used as a vacuum tube amplifier, the circuit is essentially identical to Millennia's sublime and musically euphonic M-2b front-end. The DI input offers a very high input impedance via a single 12AT7 vacuum tube circuit. STT-1 11 PARAMETRIC EQUALIZER SECTION (9) BAND IN/OUT SWITCH "IN" Pushbutton switch which places its associated EQ band in circuit or out of circuit. The four frequency bands are labeled LF (low frequencies), LM (low-mid frequencies [20 Hz - 2. 5 kHz]), HM (high-mid frequencies [250 Hz - 25 kHz]), and HF (high frequencies). An EQ band is in circuit when its associated band switch is depressed and LED is illuminated. [. . . ] You'll note that the opto-compressor gain reduction "shunt" elements, both pre-EQ and post-EQ, are passive. This means that no additional audio path amplifiers are required for dynamics control. However, in some cases, an engineer may prefer the sound of an additional Class-A discrete FET or all vacuum tube amplifier in the dynamics signal path. The opto-compressor may be used: 1. ) With vacuum tube signal path amplifier, or 2. ) With solid-state signal path amplifier, or 3. ) Without any associated signal path amplifier The Compressor and EQ share the same signal path amplifier. [. . . ]