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Gryphon Diablo 300

Last month I discussed how buying used audio gear can be a great option for any audiophile, even reviewers who have access to industry accommodation pricing (usually a discount of about 50%). This month, I put my money where my ears are.

I bought an amp.

Through the years, I’ve reviewed and owned plenty of amplifiers -- mostly big solid-state models, usually with a high proportion of their power output biased in class-A. Some of the amps I’ve owned I’ve really liked, and some I’ve really liked. Two of my most recent favorites were the Ayre Acoustics MX-R monoblocks and the Soulution 711 stereo model, each a super-amp produced by a fine company. I’ve also always really loved Gryphon’s amps, and their Antileon Evo may be my favorite from that brand -- an amplifier I could happily live with for the rest of my days.

If you read “Jeff’s Getting a New Stereo System: Part Five,” you’ve read the list of power amps I considered as contenders for my new setup. They were all fine amplifiers, but I decided against buying any of them. Instead, I righted a wrong I’d committed years before, when I sold the Boulder Amplifiers 2060 stereo amp I’d owned for little more than two years. In “The Super Products I’d Buy Today,” from September 2012, I wrote, “I once owned a Boulder 2060 stereo amp ($44,000). Then I sold it -- something I’ve ever since regretted. Although I then moved on to some great amplifiers, I still yearn for the precision, control, neutrality, and quietness that were hallmarks of the big Boulder’s sound. So I’d love to have a do-over on this one.”

I got my chance. I happened on a used 2060 that was made in 2011 (the model was discontinued in 2013). Considering that this model went into production in the late 1990s, I knew this unit had to have been one of the last 2060s to roll off the line. Its owner stated that its condition was excellent, and his detailed photos seemed to confirm that. I bought the 2060 and promptly made a phone call to Rich Maez, Boulder’s director of sales and marketing, to let him know that an amp was headed his way. I’d had it shipped to Boulder Amplifiers first -- a good high-end company should thoroughly check out a used component (for a fee, of course), so that any things that need fixing can be corrected before the new owner gets it. I found out that Boulder’s regime for checking out a used product far exceeded my expectations. Here’s the story of what my 2060 went through while in Colorado, beginning with Maez’s summary report:

The amp was uncrated and we went over it as we do all products that arrive here. Initially on the outside, things looked very good other than the usual dirt/dust/grime from a few years of use. We took the top cover off and the amp looked like it was placed in a location where there were a lot of particulates in the air that settled in the amp. We also found a loose front-panel screw, two loose ground screws on the rear panel, and a loose star ground screw on the inside rear panel.

We then took the amp apart to check some of the assemblies mounted to the heatsinks and the supervisor board mounted to the center transformer housing. All looked good and everything was put back together again.

Each of the output boards and the supervisor software were checked for updates -- none needed.

Normal production testing was carried out on the amp: thermal limiter testing, output power, distortion levels for all four phases of the amp’s operation at multiple frequencies, ability to drive a load, phase, bias setting, etc. Your amp tested normal.

After testing, the unit was burned in for 48 hours and then one last round of distortion measurements was taken. It was then listened to before heading off to shipping to have the interior and exterior cleaned and packing.

In cleaning, the interior (when possible), exterior, and connectors were all cleaned. All connectors, including XLR inputs, XLR pass through, and power connector were all cleaned with flux remover; a great cable run through a dirty connection sort of negates the cable.

The amp was then wrapped in dual-layer foam wrap and packed in its crate. It passed its checkup with flying colors.

BoulderThe 2060 arrives in its original crate.

BoulderUnpacked, all looks good.

BoulderSome assemblies removed for testing by engineer Jameson Ludlam.

BoulderReassembled, all screws checked and loose ones tightened.

BoulderMeasurements begin.

BoulderLet’s look at some numbers . . .

BoulderTHD+N (total harmonic distortion + noise) when passing a 19,993Hz (essentially 20kHz) sine wave at 44.292 (essentially 45) watts of output for one phase. Since the amp is balanced and reproduces both phases, it means the amp is outputting 90W. The measurement is 0.0013%.

BoulderTHD+N at 20kHz at 600W (max output): 0.0084%.

BoulderMeasuring THD+N with a 1V, 2kHz sine wave input: result is 20.53V output, at 0.00053% distortion.

BoulderTHD+N with a 1V, 20kHz sine wave: 20.39V output, 0.00082% distortion.

BoulderMeasuring DC on the outputs. Essentially . . . nuthin’. When the amplifier is calibrated correctly, and once the amp is warmed up, it should have next to no DC. The measurement shows 0.001mV DC.

BoulderThis last one shows what the 2060 will draw from the wall when the AC line voltage is 115V and the amp is outputting power into a load: the amp is drawing 15 amps of current from the AC line. This is used to make sure that the current draw is normal and equal from both phases on both channels.

BoulderTesting complete, cleaning is next.

BoulderButton up the top panel and we’re done!

I feel like I’m getting a new amp. The protocol that Boulder put my amplifier through was, in my estimation, complete. I particularly like the fact that, when all the initial technical stuff was done, and after a 48-hour burn-in, they remeasured and then listened to it. From here on, before I buy anything used, I’ll ensure that whatever brand I buy has a similar program in place.

. . . Jeff Fritz
jeff@soundstagenetwork.com