Sunfire TGA-7401 Amplifier
The multichannel amplifier Sunfire with hard-to-remember TGA-7401 index looks very modestly: black steel brick with a simple silver insert in the center of the fa?ade and a pressed steel case. It doesn't look like even a power amplifier. There are no heatsinks and even mesh on top and from the bottom for convection - only small cracks on the sidewalls. On a short notice you think that this is a digital amplifier, the main feature of which is efficiency rather than musicality (although we know the exceptions). However, we fly to calm whose, who hate D class: this is the device of quite traditional school of bipolar transistors, working in AB classes the author of which is famous Bob Carver. All ideas, which this audio guru wanted to realize in the line of audiophile Carver amplifiers, have been continued in the technique of Sunfire.
However, another fact is interesting. Exactly TGA-7401 is one of the most powerful multichannel amplifiers. The whole index of the device stands as follows: Theater Grand Amplifier 7 x 400 watts. Such return became possible due to quite clever system of tracking supply (patented by Bob under the brand tracking Downcoverter). The idea is simple: in a common amplifier a high potential of power is constantly applied to output transistors, but in Carver's amplifier it changes in such a way that voltage allowance in reference to amplified signal is always 6V. But the realization of this principle is quite difficult because tracking must be performed with high accuracy and speed - a separate pulsed system answers for it. Carver created the amplifier, which almost can't be forced into clipping (our power supply had up to 800W on 47 Ohm), as output transistors always work in optimal and safe mode. The idea - "complex load" - doesn't exist for TGA-7401: actually it adjusts to any. In addition, lots of energy is saved, which went into heat before.
Tracking Downconverter is not the only know-how in TGA-7401. There are two connection schemes of load in the channels for frontal speaker systems. The so-called "current sources" with big internal resistance modulate the work of a tube amp. But you can switch to Voltage Source connectors - in this case the amplifier will work as a voltage source with minimal internal resistance and as a consequence maximal damping of the load.
We started the test with "current" terminals. The device immediately conquered by sonority and a completely smooth musical balance. It has a tremendous energy in the area of the lowest "seismic" basses and elaborates very well overhangs. But TGA-7401 didn't surprise by absolute dynamics. Yeah, this device can provide a clear sound at the most powerful levels, but - without fiery temperament. The sound here is relaxed and open, rich and calm. It's amazing but having such a phlegmatic character, the sound can't be called slow. The device conveys the relief of drums accurately, deeply digs for each harmonic and is able to give copper, entrancing by its brightness, naturalness and beauty. It is really special. It's hard to remember an amplifier from this price category, which not only gladdens by detailing but also by exceptional harmonic resolution in the uppercase. Each played plate is unique and inimitable in Sunfire!
An interesting metamorphosis occurs at switching speaker system to Voltage source terminals. Bass is slightly offloaded and accelerated, overhangs become shorter and more sharp, but the energy doesn't weaken but as if brightens. Yes, the sound picture turns out to be less somatic, but more transparent and better detailed. This mode is good when you want to get the purest transmission of sound atmosphere as well as the most accurate scene.
