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THE DREADNAUGHT II IS THETA DIGITAL'S ZERO-FEEDBACK, FULLY BALANCED DIFFERENTIAL AMPLIFIER. IT IS AN AUDIOPHILE-CALIBER TWO TO TEN-CHANNEL POWER AMPLIFIER. Amplification modules can easily be installed at any time. Each module is a separate "plug & play" unit. Dreadnaught II can begin as a stereo amplifier, and grow to five full-power channels later. Use Two-Channel modules in any of Dreadnaught II's 5 slots: you can have up to 10 channels. Dreadnaught II is a tour de force in design, execution, and audible performance.
Why does Dreadnaught II Exist?
Home theater creates a new amplifier category. Most amplifiers made for home theater come from companies that do not make music-oriented amplifiers. For music, these amplifiers are highly uninspiring: sound quality simply was never a factor in their design. Some "high-end" companies are now offering multi-channel amplifiers, better than amplifiers from home theater oriented companies. But compared to high-end stereo amplifiers from these same companies, the multi-channel amps sound lackluster and pallid. It is tempting to reason that there is a natural enmity between quality and quantity. Granted, multichannel amplifiers are designed to take price into account. But we are aware of economies in combining channels on one chassis. A well-designed multichannel amplifier should offer better per-channel quality. We perceived a need for a multichannel amplifier that takes musical performance seriously. (We could as easily call it a high-end amp that takes multichannel seriously.) The Dreadnaught II is not a compromise. It is not a downgrade of any preexisting two-channel design, or a cynical nod to a market presumed to be undiscerning. The Dreadnaught series was conceived and created from the ground up to deliver flexibility and superlative performance; to meet needs that simply have not been met before. Power Home Theater amplifiers are generally right at the borderline of offering sufficient power. Speakers starved for power can't perform up to their capabilities. Also, an amplifier strained to its limits produces fatiguing distortion. An inadequate power amp can leave you feeling stressed and drained after an evening's entertainment! Each Dreadnaught II channel is rated at 225 watts into 8 Ohms, 450 into 4, and even more into 2 Ohms. Your Dreadnaught II can be a two-channel amplifier, or load it with up to five identical channels. Two-channel modules can be used in place of any of the five single channels, each comprising two channels, less powerful than the single-channel modules, but otherwise having exactly the same circuit topology. Modular We took some design inspiration from our Casablanca and Casa Nova controllers, modular configurations affording total flexibility. The quality of a Dreadnaught II amplifier doesn't go down when you add more channels, and you aren't forced to get everything all at once. Theta's "open architecture" components allow you to custom configure your system to your needs. You don't pay extra to start with a stereo amplifier and add channels later. Zero Feedback Dreadnaught II uses no global negative feedback. What is a feedback? Like a snake biting its tail, a negative feedback loop sends some of its output signal back to its input. To cancel out the errors that have crept in during the amplification process, a compensation signal is applied at the input. Obviously, this correction cannot actually take place instantaneously. Small amounts of feedback, within a single gain stage (called "local"), help ensure circuit stability and keep the circuit's processes on track. Delay is miniscule in local feedback. Nearly all analog circuits rely on this kind of benign feedback. However, when applied to an entire amplification chain, often comprising several gain stages, time delay becomes a significant problem. The "envelope" is too big, resulting in serious phase shift and intermodulation of the signal with its own error products. This fantastic complex of distortions goes unmeasured (in all the usual specifications), and is not correctable." Dreadnaught II uses none of this kind of "global" feedback! Balanced Differential all the way What does that mean? In essence, each amplifier module is really two mirror imaged signal paths for each channel. Balanced signals coming in to the amp are kept intact. Single-ended signals are "balanced" at the very first gain stage: the signal is cloned, and the phase-inverted duplicate amplified through a path identical to its twin. The amp's two signals move the speaker's elements in a "push-pull" fashion. Discontinuities arise in the course of amplification, but do not survive in a balanced/differential circuit. Anything not exactly "mirror imaged" between the two signals is eliminated (called "common mode rejection"). This preserves the integrity of the amplified signal. This no-compromise technique is rarely used, however, because it requires almost twice as many devices as conventional, single-track amplification. Most companies just don't do this rigorous a job. We wouldn't invest this much in high quality components either, if we could figure out an easier way of getting such pristine results. Features and controls Dreadnaught II's Standby Mode (front panel push button) mutes and reduces idling current to all channels. A second button selects stereo or surround channels (assigned by a switch on each module). These two controls can also be activated via remote control jacks, which bring trigger signals from another unit, such as a Casablanca or Casa Nova. An optional bi-directional RS-232 port is available: connected to a computer or other control device (e.g. AMX or Crestron), this allows the Dreadnaught II's controls to be activated; status information about the number of channels present, rail fuses, thermal sensors, and modes can be monitored. Each module has LED indicators for fuse status and temperature conditions. Stability; Reliability Throughout its design and construction, we have built Dreadnaught to the high quality standards you expect from Theta. Dreadnaught II's circuit designs,
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