AkitikA GT-102 power amplifier

An e-mail from an old audiophile pal: "Herb, my buddy owns a recording studio, and he told me one of his $10k reference amplifiers stopped working and the manufacturer said it would take months to be repaired. So he went online and bought this 60W AkitikA solid-state amplifier to use while his big amp was being repaired. The trouble is, the kit cost only $314. (The studio guy bought his assembled and tested for $488.) Now, he likes the AkitikA more than his broke-down reference amp."

My friend wondered if I wanted to review the AkitikA amp (the name is a palindrome, based on a kit).

"Hell yes!" I told him. "Kits are my roots!"

When I was in high school, my best friend was a radar technician for the Navy. He taught me Ohm's law, and how to solder, dress wires, and use a multimeter. He practically forced me to build a Dynaco (footnote 1) Dynakit Stereo 70 tube amplifier, as well as the matching PAS-2 preamplifier and FM-3 stereo tuner. I didn't want to take tubes to college, so I also built Dynaco's solid-state PAT-4 preamplifier and Stereo 120 amplifier, which I used to drive Dynaco's A-25 loudspeakers. Oh, how I loved them. To this day, Dylan and the Doors have never sounded better!

After moving to New York City, I built a solid-state Hafler DH-101 preamp and two (!!) DH-200 amplifiers, which I used to drive stacked pairs of Large Advent loudspeakers. Yahweh, Bob Marley, and The Specials loved this potent lively-up system as much as I did. Next, I started reading Audio Amateur and Speaker Builder magazines, buying used test instruments, and modifying my Dynaco and Hafler gear. By the late 1980s I'd advanced to building simple tube amplifiers from scratch, using parts cannibalized from antique radios. (I worshiped at the Philco 16B Tombstone.) Solder fumes, wire strippers, and building amps remain very appealing to me. For me, kits were the start of a new life—one that led me to secret societies and darker corners of the audio underground.

When I asked John Atkinson if I could review AkitikA's GT-102 power amplifier, he said okay, but suggested that, because he would be testing it on his lab bench, I should request the factory-assembled, pre-tested version ($488). Which I did.

Description
Because the GT-102 is available as a kit I begin my description of it by quoting AkitikA's "Satisfaction Guarantee" for this US-made amp:

• Buy the kit.

• Build the kit.

• Listen to and enjoy the kit.

• If within 30 days of receiving the kit you aren't satisfied, return the kit. So long as your kit is correctly assembled, we'll refund the price you paid, you just pay return shipping.

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The GT-102 is a class-AB, 60Wpc stereo power amplifier in a case made of relatively thin steel. Its front panel sports only a logo and an illuminated, bright green plastic rocker switch for power on/off. On the rear panel are only an IEC power-cord inlet, two gold-plated RCA jacks, and two pairs of generic speaker binding posts. The GT-102's interior is spartan, but studying its layout gives the potential kit builder a good idea of how much screwing and soldering will be required to build it.

The first thing to note is the steel wall separating the audio circuitry from the toroidal mains transformer and regulated power supply. Note the three deep-finned heatsinks: one behind the rear panel, for the power-supply regulator, and two in a row along the inside of the left side panel, one per channel, to cool the two LM3886 power operational amplifiers.

Now, before you get your knickers in a knot about an "audiophile-grade" power amplifier based on a lowly op-amp—instead of this year's fashionable MOSFET, JFET, SIT, or bipolar device—you must understand that the AkitikA's LM3886 op-amp is notorious and fashionable. The roots of the storied LM3886 can be traced back to 47 Laboratory's 4706 Gaincard integrated amplifier, designed by Junji Kimura, which I reviewed for Listener magazine; Robert Deutsch reviewed it for Stereophile in December 2001. The Gaincard, introduced in 1999, had only nine parts per channel, short signal paths, minimal power-supply capacitance, and, with only one of 47 Lab's Power Humpty power supplies, cost $3300 (a second Power Humpty cost an additional $1800).

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The 4706 Gaincard's high price, radical simplicity, and unorthodox power supply spawned concern among measurements-oriented audiophiles, but word quickly spread about how musically satisfying it could sound. After reviewing it, I bought the Gaincard and used it every day for 10 years with a pair of Rogers LS3/5a speakers. I've subsequently compared my Gaincard to one of its clones and one DIY version, and learned that all LM3886 op-amps are not created equal.

In using power op-amps, implementation is key. PCB layout, wiring routes, grounding strategies, heatsinking, power transformers, and especially power-supply design, will affect stability, transparency of sound, and the ability to drive speakers. My listening for this article, and what I see inside this amp, suggest that AkitikA's owner and designer, Dan Joffe, has done a smart job with this LM3886 implementation.

Kit builders should know that each of the GT-102's three circuit boards is fitted with a lot of little parts, most of them resistors whose coded stripes identify their values. To build a GT-102, each tiny bit will need to be found, positively identified, properly positioned, and soldered to its board. (I recommend soldering no parts until each PCB board is stuffed full, in mechanically sound fashion.) That done, the rest of the assembly consists of bolting and screwing the boards, binding posts, power switch, ground lug, and power transformer to the GT-102's chassis. I suggest working slowly and patiently while breathing fresh air (it's best to solder in a place with good ventilation), and triple-checking each step.

The minimum tools required for assembly are: a 30W, pencil-type soldering iron; a small sponge; fine (0.032"), 60/40 rosin-core solder; wire cutters and strippers; #1 and #2 Phillips screwdrivers; needle-nose pliers; a set of basic nut drivers; an inexpensive digital multimeter, to cross-check resistor values against your reading of their color codes; good lighting; and a magnifying glass.

AkitikA's website says that assembly should take about eight hours, and that 97% of all first-time kit builders complete the GT-102 without a hitch. The remaining 3% get it right in the end, with a little easy guidance from AkitikA.

I studied the assembly manual and found it exceptionally clear and idiot-proof. It looks just like a Dynaco or Hafler manual.

Listening
I cooked the AkitikA GT-102 on my workbench for three weeks, while writing the Follow-Up on Joseph Audio's Pulsar loudspeaker elsewhere in this issue. The system I used with the Pulsars comprised Mytek HiFi's Manhattan II DAC, and Pass Laboratories' HPA-1 preamplifier and XA25 power amp. I thought this was the most balanced and spatially descriptive system I'd assembled since I began writing for Stereophile in 2014. Jeff Joseph, of Joseph Audio, heard it and approved. So did John Atkinson. Stereophile's erstwhile videographer Jana Dagdagan and I made a binaural video of its sound. so you can experience it, too.



Footnote 1: The other division of AkitikA LLC is www.UpdateMyDynaco.com, whose name explains all.—Ed.

COMMENTS
Bogolu Haranath's picture

Goes to show more money can't always buy more happiness ..............

hifiluver's picture

...but for the same money you can buy even better.

Ortofan's picture

... to delete the output coupling capacitor and lower the output impedance?

Jason P Jackson's picture

How could that be? I'm building one.

Oh I see, It's a 1k sine. Still, nice measurements.

Anton's picture

Great glimpse!

trmntr03's picture

I have a DAL Audio 3875 Chip Retro Amp, purchased used (virtually new, though) at Audiogon about 9 months ago at $158 ($350 new then, now at $400 new) for my 2nd system, and I can't be happier. It is build to the order in the U.S. They also make 3886 amp at the same price. Anyway, now I am a firm believer of the well-designed chip amps regardless of the price.

jorgen's picture

Hifiluver can you really?

Ortofan's picture

... for $299 the A-150, which is rated (with both channels driven) at 75 watts RMS per channel into 8 Ohms and 150 watts RMS per channel into 4 Ohms.
For $399, their A-300 is rated (with both channels driven) at 150 watts RMS per channel into 8 Ohms and 300 watts RMS per channel into 4 Ohms.

invaderzim's picture

comparison with those would be great

invaderzim's picture

Herb, you are my new hero for reviewing an amplifier that is sold in kit form.

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