DRACONIA Audio Precision Test 
The Draconia
Draconia is the first of the four channel amplifiers which we manufacture. It is rated at 70watts continuous power per channel into 4 ohms and 140watts per channel into 2 ohms. All crossovers are fully variable 24dB/Octave with a range from 46Hz to 3.5KHz.
Chs 1+2 may be run FLAT or HP or LP
Chs 3+4 may be run FLAT , HP,LP or BP (Bandpass). When in LP mode the signal may be also selected from all four inputs. So if the amplifier is run as all chs in LP mode front and rear signals are fed to all four channels.A low frequency boost control allows for up to 18dB of boost at the centre frequency of 44Hz. The level controls allow signals from 260mV to 8v to drive the amplifiers to rated power.
The line output has its own selector. It can chose between HP or LP signals from Chs 3+4.
The twin selector switches, when in FLAT allow for the complete bypass of the front end with the exception of the level controls. Complete ground isolation is achieved through the use of our unique Balanced Differential Drive preamplifier. At present we offer the choice of two IC chipsets for the preamplifiers. The standard uses a low noise bipolar input style op-amp and the option is a BIFET Burr Brown chipset.
The main power amplifiers in Draconia are fully complementary from input to output, they use temperature compensated constant current sources to drive the differential input transistors. This ensures that with varying temperature the DC conditions within the amplifier are kept constant. The inputs are fully balanced, using our Differential Drive circuit. The circuits employ substantial amounts of local feedback which allows us to use very little global feedback. Low THD was not our goal, rather sound quality. The output stages use high frequency Bi-polar output transistors. These have a Ft of 20MHz and are very linear with respect to gain. Draconia has FOUR 100 watt putput devices per channel. Zed has always been a strong proponent of having output stages vastly over rated. The reliability of the amplifier is improved when output devices are run at fractions of their capability. Using multiple lower powered output devices is superior to using single high powered devices. Please refer to the section under Techtalk Output Transistors.
The power supplies are fully regulated and there are no less than THREE separate sets of these. The main high current pair run the output stages, a regulated +/- 12v pair run the differential amplifiers and their associated constant current sources and the last pair which run from a completely separate transformer supply DC to the preamplifiers. This isolation assures minimum interference from one amplifying stage to the next. The main high current supply uses a bank of TEN 2,200mfd capacitors together with EIGHT ultra high current Mosefets as the main switching elements and the pair of high speed switching diodes feed, through a common mode choke, another bank of 18,800mfd for the main amplifier's supply. Since the power supply runs at about 60KHz this is ample capacitance to assure full power at 10Hz.
The mechanical parts were chosen for reliability and cosmetics. RCA sockets are solid gold plated machined brass types with teflon inserts. The power and speaker connectors are again solid gold plated machined brass types. The Power terminals accept up to #4 wire and the speaker #8.
Draconia Specifications
Output Voltage (volts into 2 ohm) per channel 16.73v
Output Voltage (volts into 4 ohms) per channel 16.73v
Output Current (amps into 2 ohm) per channel 8.36A
Output Current (amps into 4 ohms) per channel 4.18A
Continuous Output Power into 2 ohm per channel 140wx4
Continuous Output Power into 4 ohm per channel 70wx4
Typical Output Power into 4 ohm per channel (0.8% THD) 95wx4
Continuous Output Power 2 channels bridged into 4 ohm 280wx2
Continuous Output Power 2 channels bridged into 8 ohm 140wx2
Minimum Speaker Impedance per channel 2 ohm
Minimum Speaker Impedance in Bridge Mode 4 ohm
Power Response at any power into 4 ohms/channel 10-100KHz -3dB
Frequency Response at rated power into 4 ohms/channel 10Hz-25KHz -0.1dB
Input Voltage range for rated power into 4 ohms 0.26-8 volt
Input Impedance 47K ohm
Noise below rated output (30KHz limited) -98dB
Channel separation at 2KHz >80dB
Damping Factor at 20Hz with 4 ohms >180
Total Harmonic Distortion with 4 ohm 20Hz-20KHz
From 1 watt to rated power. Typically less than 0.05% <0.08%
Intermodulation Distortion <0.08%
Phase response at 20KHz Lagging 10 deg
Slew rate (volts per micro second)-In”Flat” mode 15
Low Pass Crossover (all are 24dB/octave) 46Hz-3.5KHz
High Pass Crossover (all are 24dB/octave) 46Hz-3.5KHz
Equalization (Zero to +18dB variable control) Bass Boost @44Hz
Remote Level Port with control N/A
Line Output Yes
Protection - Short Circuit, DC, Thermal Yes
Power Source 10-14.5v DC
Current Consumption with Sinewave at 4 ohms 40A
Current Consumption with Music at 4 ohms 12A
Idling Current <2A
Fuse rating with 4 ohm load/channel 50A
Fuse rating with 2 ohm load/channel **** 70A
Size W x H (302.22mmx74mm/11.9”x2.91”) x L 444mm/17.48”
Shipping Weight (Kg/Lbs) 11.8/26
**** Under normal operating conditions the fuse rating for 4 ohm loads will suffice for 2 ohm loads. If the amplifier is driven for long periods of time into
2 ohm loads per channel the fuse rating may be increased as shown. DO NOT OVER FUSE ANY AMPLIFIER.
