Gryphon Essence Mono Power Amplifier
“Oh good!” thought to himself, “Another Gryphon component that needs checking.” As eloquent and insightful as this statement may be, there is an even more illuminating backstory.
I’ve been aware of Denmark-based Gryphon Audio since the advent of the Gryphon Exorcist, a now-obsolete demagnetizer that costs far more than your average break-in CD, but I only met Gryphon Electronics at audio shows a few years ago. While they were initially only available for review as a complete package, Jim Austin was able to have me review the D / A processor on the Gryphon Ethos CD player ($ 39,000). I covered this player in the January 2020 issue of Stereophile. To my surprise, I found the ethos to be “an open, wonderfully detailed, fresh-sounding entity that makes listening an absolute pleasure”. I didn’t expect my experience to be this positive.
Baggy for kitty
Why was I surprised? Because the sound I heard at AXPONA 2019 in an All-Gryphon system from the Ethos was bright and without warmth – so much so that I fled the room without taking any notes. It wasn’t until recently, after spending some time with the Gryphon Essence monoblock power amplifier ($ 45,980 / pair), that Gryphon’s sales director, Rune Skov, confessed to me that the sound in that air-walled convention center on the second floor was so untamable – so far from what he wanted to present – that he had advocated a static display. Static displays rarely perform at audio shows, so Skov put his best foot forward and continued as if everything was fine. And that’s how I felt, without letting the cat out of my pocket, when I heard the Essence Monoblocks.
The brand new, fully balanced Essence monoblocks are the lowest performing monoblocks in the Gryphon line. They don’t come cheap. The essences are specified to deliver 55 watts into 8 ohms in pure Class A mode – that’s $ 836 / W. If you have speakers with a nominal impedance of 4 ohms, like mine, Wilson Audio Alexia 2s, those are 100 Essence class A watts in 4 ohms at 418 USD / W a relative bargain. Regardless of the nominal impedance of your speakers, you probably won’t find many people who consider the essence a bargain product. That doesn’t necessarily mean they aren’t good value for the right customer.
Before I said “yes” to this test, I needed to be certain that the Essence Mono could handle my loudspeaker, the impedance of which in the bass drops well below 4 ohms. At first, Gryphon essentially allayed my concerns, but it was eventually fully addressed in a joint Skype conversation with Skov and Gryphon’s chief designer, Tom Møller.
“When we started developing the Essence mono amplifier, we used it on our less efficient speakers, which are pretty difficult to drive, so we could make sure the amplifier was driving them and had several 8-inch drivers super tight “said Skov,” Our goal was to control inefficient speakers, be extremely fast, and have a lot of resolution and a lot of musicality. ”
“55 W at 8 ohms is not much,” Møller admitted. “We wanted to make sure that the small amplifier could drive larger speakers with adequate sound pressure.”
Møller, a 20-year-old Gryphon veteran who is responsible for the topology and internal design of the company’s amplifiers, preamps, and CD players, stated that Essence’s performance in Class A (high bias) and Class AB (low ) is identical to pretension). “In AB, the first 7 watts may be class A, but most of the time the amplifier works in class AB.” I asked if the monoblock had been optimized for high or low preload. I had already experienced the sonic differences between the two prejudices of the essence and strongly represented my own views.
“It’s optimized for high bias,” Møller replied. “All of our products are. If you set the essence to a low bias, the sound quality will almost certainly go down. It’s not terrible? You can listen to background music etc, but if you are serious about listening and switching, high bias achieves it the best temperature in half an hour or so. On the other hand, if you turn on the monoblocks from the cold, you have to wait at least an hour. If you start from the cold and give them a couple of high bias hours they will perform great, and when If you give them more time, they can open up a little more. ”
That was exactly what I had already noticed, so I found Møller’s confirmation reassuring.
To make sure I always auditioned the amplifiers at their best, I turned them on in low bias mode between evaluation sessions and switched them to high bias at least an hour before critical listening.
The biased light show
Beauty, like preference in music, is a matter of personal taste. For me, the Essence with its polished black acrylic finish is Scandinavian design in its most elegant form. The back of the monoblock is simple: a 20 amp IEC connector, a single XLR input, and two large, proprietary, gold-plated binding posts that are sensibly placed and a breeze to open and close. It’s the faceplate that is unique.
At the bottom of the amplifier, near the front edge, are three controls that are easily accessible to anyone who can bend over without falling. The main on / off switch is located in the middle. It is flanked by two touch-activated buttons: “Mode” on the left and “Bias” on the right.
As expected, the bias button determines whether the amplifier is operating with low or high bias.
The mode button has nothing to do with how the Essence controls speakers. Everything revolves around the light show on the front.
When you set the main switch to the “On” position, the Gryphon logo on the front lights up in a subtle red and a small, touch-activated “Standby / On” sensor button directly below it lights up red. If you touch the sensor lightly, a long horizontal touch bar will turn blue, and both it and the logo will flash for about 25 seconds. After that, in mode 1, the “On” button turns faint green and the bar remains blue. Then, if you change the amplifier bias, the bar will flash the color corresponding to the new red for high, green for low bias setting for 10 seconds before returning to blue.
In mode 2 the light does not turn blue. The color (red or green) that corresponds to the selected preload remains. In mode 3 “Stealth” mode, all displays on the front panel with the exception of the green “On” symbol remain dark until the preload changes. At this point, the touch bar will blink in the appropriate color for 10 seconds before proceeding dark again. That is the most complex part of the functions of this amplifier.
When asked what else is special, Møller pointed out the new Sanken power transistors from Essence from Japan. “With the Diablo 300 integrated amplifier, we used four sets of power transistors in each stereo channel. Here we use five sets to reduce the output impedance. In addition, with a monoblock, the two channels are coupled in parallel to create further lower output impedance. This makes the power amplifier very powerful so it can deliver a lot of current.This is the first step in making a very good power amplifier.
“The voltage amplifier stages are also very important. We use two JFETs as a buffer in the input stage and go to a symmetrical voltage amplification stage with two differentials and bipolar transistors. We also use surface mount resistors in the voltage amplification stages throughout the amplifier. Each stage operates in Class A. The power supply part, which uses a bespoke toroidal transformer with very little mechanical noise / hum, is not directly in the signal path, but indirectly affects it also have a lot of capacitance 220,000 µF per side, which because it is parallel in the monoblocks, Means 440,000 µF for each channel.
“The power supply for the voltage boost stages is fully regulated and very low noise to prevent smearing of small details. It is decoupled with good quality polypropylene capacitors. Many of our larger amplifiers use 10 pairs of output transistors coupled in parallel. Usually when you do, you have a large capacitance in the base of the transistors which is difficult to drive and can reduce the amplifier bandwidth, to avoid this we use a lot of power to drive the output transistors – our secret.
“The circuit board is almost the most important component as it contains all of the signal and ground traces that need to be optimally placed to avoid noise and smearing of lines and details. The signal paths on the circuit board are intentionally very short. We do not do this. ” Use internal connections to guide the sound. All sound is conducted through high-quality cables that are soldered into the XLR sockets on the back of the Essence and lead directly into the circuit board. The only wires we’ll use go to and from the board. A. A small cable about six inches (6 inches) long leads to the speaker terminals. It’s the same silver / copper wire used on the Diablo 300, our largest and most successful integrated amplifier, and on our speakers. We don’t use an internal power supply or signal cabling as strictly necessary as it can be difficult to wire components perfectly during production. In the worst case, a signal cable placed closer than ideal to a transformer can cause an audible, induced hum when wiring from the board, the layout is consistent, ensuring that every Essence power amplifier sounds the same. ”