April 1, 2009

Sunfire Theater Grand Multichannel Amplifier TGA-7401

"As one of the leading characters in William Shakespeare’s [A] Midsummer Night’s Dream, Puck boasts of his pranks of changing shapes, misleading travelers at night, spoiling milk, frightening young girls, and tripping venerable old dames."

I quote that passage from the Encyclopaedia Britannica because I wanted to describe Sunfire’s founder as "puckish." I haven’t actually seen Bob Carver frightening young girls -- unless, of course, you count all the audio-abhorring wives of the 1970s who were caught in the crossfire as their husbands demonstrated how loud a 350W Phase Linear amp could play (i.e., loud enough to spoil milk).

Instead, I wanted to focus on Carver’s shape-changing pranks -- such as the one in which he bodaciously claimed that he could make one of his amps sound like any other amp in the world, without even a glance inside the other amp to see what parts had been used. He called this Transfer Function Duplication, but the idea behind it is very simple: If you change the phase of one of two identical signals, the result, no matter how loud you play them, should be silence. All Carver had to do was futz with the sound of his amp until his TFD test produced silence. He then called in the doubters to have them identify which amp was which in a double-blind test. No one could reliably do so.

Their response? Double-blind tests don’t work. (Oops! Wrong.)

Carver’s response? Build the Carver M1.5t amplifier, which sounded "the same" as the Mark Levinson ML-2; and the Carver M1.0t, which sounded "just like" the Conrad-Johnson Premier Five. Take that.

No one in the industry was very happy. Carver and his fans thought it was hilarious. The rest of us wondered if the dude had really figured something out.

Though Bob Carver’s role at Sunfire is now somewhat reduced -- having sold the company to home-security firm Nortek, Inc., he’s now Chief Technical Officer and no longer CEO -- Sunfire still produces his handiwork. Sunfire’s massive Theater Grand Amplifier TGA-7401, a seven-channel power amplifier ($4450 USD), puts out a very Carver-like 400Wpc, all channels driven into 8 ohms. When it arrived here, in its manual I found the term "Vacuum Tube Emulation," which purportedly allows those who love the sound of vacuum tubes to re-create their sound. The old dog just can’t keep from nipping at the big dogs’ heels.

The TGA-7401 is also Carver-like in that, like his famous baby cube woofers with multi-thousand-watt power amps, at 34 pounds, the huge TGA-7401 is light for the power it is rated to output: 400Wx7 at 8 ohms, or a total of 5600W into seven 4-ohm loads, and stable down to 1 ohm, where it puts out enough power to drive a front-scoop Bobcat. And it does so while drawing about 35% less current than most class-A/B amps. It accomplishes this sleight of hand by using Sunfire’s patented Tracking Downconverter, a device that previews the signal to determine how much power it will require, then provides precisely that amount of juice, nothing more, nothing less.

The TGA-7401 measures 17"W by 5.75"H (including feet) by 16.7"D and comes with a five-year transferable warranty. With its big vertical silver strip down the middle, the TGA-7401 should make interior designers happy, and makes a nice visual match with their Theater Grand Processor TGP-401 preamplifier-processor. Other than the strip, there’s a subdued label, a power light, and a power amp’s standard blank faceplate. For those of you with professional component racks, Sunfire offers the SRK-200, a rack kit that puts the TGA-7401 into a 4U-size space.

One thing absent from the front panel is a power switch. That’s on the rear, along with a three-way switch for controlling the power switch’s behavior: Auto On (the amp comes on almost instantaneously, then shuts down when there’s been no music or sound for 30 minutes), Always On, and Always Off.

Also on the rear are 14 unbalanced RCA inputs and seven balanced XLR inputs. Each channel’s pair of RCA inputs are joined internally, which permits all sorts of daisy-chaining possibilities. The front left and right channels offer the choice of current-source or voltage-source outputs. More Carver puckishness: He recommends that you biwire your speakers, using the current source for the midrange and tweeter and the voltage source for the woofer, which, he says, yields a tubelike sound where that sort of mellifluousness helps, and oomph to help the woofers woof. Tube and transistor sounds from the same amp? That should trip up some venerable old dames.

For folks who like to add their own power cord, the Sunfire’s IEC cord is detachable. The speaker binding posts accept bare wires, spade terminals, and dual or single banana plugs, and though they’re a bit too close together for my hands, they’re sturdy enough to take a good torquing-down.

Installation was straightforward and quick, especially as the TGA-7401 is a good deal smaller than my Anthem Statement A5 amp. The Sunfire took a while to warm up enough to sound its best, though it sounded great after being left on for just one night. After that, the TGA-7401 keeps enough current running to keep the amp warm and awake.


The Sunfire TGA-7401 had that sense of effortless reproduction and open space you hear only when an amplifier has plenty of headroom. Take a film with a great sound design, such as Hellboy II: The Golden Army. When 70 times 70 of the Machines of the Golden Army wake up and attack, the sound comes from everywhere, hard and fast. The Sunfire retained the realistic soundstage throughout these scenes -- one of my surround speakers gave out before the amp did.

The Region 3 version of House of Flying Daggers has a killer DTS soundtrack, especially the "Dance of Echoes" chapter, in which pounding percussion leaps from channel to channel. The Sunfire’s sound was pure and clean, with no sense whatsoever of any compression.

The Sunfire also made magic with music. Paul Daniel and the Bournemouth Symphony’s superb DVD-Audio recording of Vaughan Williams’ A Sea Symphony (Naxos 5.110016) has roaring bombast and intervals of idyllic splendor. Again, everything existed in a realistic soundstage, which remained realistic regardless of the volume level. Though the song doesn’t rock my boat, Sting’s "Thousand Years," from the DVD-A of his Brand New Day (A&M 104719), is gorgeously recorded, with very specific placements of instruments and a shimmering sound that was dazzling through the Sunfire. In fact, everything I threw at the TGA-7401 sounded superb -- pure, transparent, rock-stable, and graceful.

Some of my fellow writers on the SoundStage! Network think that $10,000 per amplifier channel is a bargain. They might think me crazy for recommending something that costs only $636/channel. For that matter, my sweet-sounding Anthem A5 amp costs a mere $500/channel. But then, amplifiers in the quality range of Anthem’s and Sunfire’s sound awful darn good to me.

Would I pick the Anthem over the Sunfire? Yes, but not because of the Anthem’s burnished sound, which I love. I need only five channels of amplification, so the A5 is enough for me. The two amplifiers do sound slightly different, however, mostly due to the unforced headroom the Sunfire has at really loud volumes.


The Sunfire Theater Grand Amplifier TGA-7401 has enough power to move mountains with gorgeous subtlety. If I had two main speakers capable of being biamped or biwired, the TGA-7401 would be my choice. If I were using Sunfire speakers, again, the Sunfire would be my choice: Given the efficiency and maximum output of Sunfire speakers, they should be able to handle, at least in the short term, more than 300W, and that 100W of headroom only translates into a little over 1dB of sound -- so all that power is a good investment.

The puckish Bob Carver has done it again: an amp that shape-changes between two great but different types of sound (tube and solid state), has plenty of power and a nice, long warranty, and at a fair price. It all adds up to another in the long line of winning Carver amplifier designs.

. . . Wes Marshall

Sunfire Theater Grand Amplifier TGA-7401
Price: $4450 USD.
Warranty: Five years parts and labor.

1300 New Circle Road, Suite 150
Lexington, KY 40505
Phone: (859) 514-8290
Fax: (859) 269-7972

Website: www.sunfire.com


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