Muscle tissues and Thoughts: The PA-10 Power Amplifier from Gold Be aware
It’s been a couple of months since we looked at Gold Note’s £ 2500 DS-10 streaming preamp (see here). By combining a small form factor with a wide range of functionality and excellent sound quality, the DS-10 made a positive impression. That positive attitude has grown since then in the past few weeks with the addition of the DS-10’s stablemate, the PA-10 power amplifier (£ 1264 / $ 1699 / € 1390).
The two look like natural bedfellows: a compact and elegant hi-fi system that would obscure even the most reluctant audiophiles. (There is no reward point program for enduring poor exterior aesthetics when aiming for better sound – Ed). The combined price of this two-Fer of £ 3800 is in the luxury lifestyle system range. Does the little PA-10 match the DS-10 in terms of sound? Or had to give something to reach this price / size point? And what about in an environment without a Gold Note? Can it thrive with equipment from other manufacturers or does it need the comfort blanket of its siblings?
Gold Note shipped 2 x PA-10s so I could try both stereo and mono mode. Continue to play.
The PA-10 is a 200x80x260mm (WHD) class A / D hybrid power amplifier. In stereo mode it is specified at 75 Wpc in 8 Ω (150 Wpc in 4 Ω, 300 Wpc in 2 Ω). Enough for speakers with average to high sensitivity.
Do you need (or want) more performance? Dip in a rear-mounted switch and the PA-10 transforms into a monoblock. You need two for stereo – twice the cost – but the amortization is four times the power: 300 Wpc in 8 Ω (600 Wpc in 4 Ω, 1200 Wpc in 2 Ω).
Additional flexibility is provided by variable attenuation – the control an amplifier has over the speakers – achieved by changing the amplifier’s output impedance. Measured as the ratio between the speaker impedance and the amplifier’s output impedance, the default setting of the PA-10 is 250 (high) and is suitable for large or difficult-to-control speakers, according to Gold Note. Low attenuation – at 25 similar to valve amplifiers – possibly (but not always) better for smaller speakers. Experimenting with your own setup is the order of the day. Made easy, we can even switch the damping during operation.
The PA-10’s output stages use gallium nitride MOSFETs, which double the output power every time the impedance is halved. It is a proprietary design whose behavior is intended to mimic that of a pure Class A design, but with greater energy efficiency. Switching power supplies bring the wall juice. Linear power supplies do not have a monopoly on high-end audio applications.
Appearance, functionality, build
The front panel of the PA-10 is refreshingly clean. A small Gold Note logo and a blue power LED. That’s it. In a rack, the PA-10 is largely anonymous (in a good way). The omnipresent ventilation slots of Gold Note are to be emphasized on a frame.
The back is used for a power amplifier. Balanced and single-ended inputs are expected at this level, but balanced outputs? This has nothing to do with operating the PA-10 in mono mode. Rather, they allow an additional power amplifier to be connected to the PA-10. Either to amplify your speakers or to run a second set of speakers in another system. Of limited use, I would have thought.
Three dip switches switch between stereo / mono, symmetrical / single-ended and high / low attenuation. Blue LEDs indicate the status. There are also 12V triggers to turn on the PA-10 through the DS-10. This is useful if the PA-10 on / off switch is also on the back. Finally, there are four high quality speaker tie posts.
When we approach the PA-10 while it is idling (no music playing), we hear a slight ticking sound. It cannot be seen from a distance of more than 50 cm. When music is played it is completely inaudible. This can be a problem if you plan to use the PA-10 in a desktop system (you’re in luck). Not a practical problem for this review, but readers should be aware of it. Gold Note explains:
“The noise is due to the special power supply that we developed specifically for the PA-10. If the power supply were fully shielded, the noise would not be detected, but given its performance, we opted for a design that would guarantee optimal cooling, which we refer to as the “current safe design”. When the PA-10 is idle, it produces the almost inaudible sound that disappears completely when the PA-10 starts playing music. “
Elsewhere, the fit and workmanship are exemplary, as is usual for Gold Note. Together, the DS-10 and PA-10 take up surprisingly little space on the shelf. Conclusion: Small footprint, flexible functionality, high performance, good looks.
Whether in stereo or mono mode, the PA-10 Graham LS6 speakers (£ 2,300) are powered by Tellurium Q Black 2 cables (£ 270). IsoAcoustics Gaia 3 feet (£ 500, review here) supported the LS6 stand.
Two streaming preamps were used – Gold Note’s DS-10 and Cambridge Audio’s Edge NQ (£ 3500, review soon). Comparisons were made to the power amplifier portion of the built-in Ayre AX-7e ($ 3950) using its preamp bypass inputs.
Before that I measured the temperature of the GoldNote DS-10 as a preamplifier and the Ayre AX-7e as a power amplifier. It offers a boneless sound, slightly warm in the valve shape and full of texture. The DS-10 preamp makes sure we hear the details that Ayre’s own preamp masks. Overall, it’s a sound I’m familiar with. Heart more than head, emotion before analysis.
Out with the Ayre, in with a single PA-10. The differences are soon apparent. More clarity and control from top to bottom. The swirling soundscape of Derrick Hodges Color of Noize (brilliant album) is far easier to decipher on the PA-10 than on the Ayre, especially when the music turns up a minute before the first track. Pulsating rhythms and 10 dB louder, the Ayre paints an impressive wall of sound and sucks us into the vortex. The PA-10 surpasses it with greater dynamics and even more dynamics. The bass is fuller and more controlled. And the PA-10 better reveals the details of what is going on. Brains and muscles.
I switch from John Potter’s caring sleep to Stephen Stubb’s ” Refrains ”. This is my favorite music for reserved beauty. And the PA-10 nails it. The silence between the notes is delightful, the decay of the notes means a level of delicacy I have never heard before. Sarah Jarosz ” Hometown ” from World on the Ground is treated just as well. Jarosz’s voice is singer-songwriter and small band Fayre. It is beautiful because of the small gold note, its growing maturity is obvious.
Overall, the PA-10 has a detailed and controlled sound. No wonder this is a gold note strength, at least with the equipment I’ve tried. The difference between PA-10 and precision is holding the baby (warmth, texture and richness) while the bath water (flower and smear) is thrown away. The PA-10 sounds both nourished and detailed.
I switch to low attenuation. Think a quarter of a spoonful of sugar in an espresso or a splash of water in a malt whiskey. The music is softer and sweeter. Flow replaces precision. That would normally suit my preferences, but a slight looseness has crept in. It’s marginal, but after some thought I revert to high attenuation.
Different speakers, electronics, rooms or preferences can favor low attenuation. The PA-10 gives us options. Useful when speaker upgrades are imminent.
I add a second PA-10 and dip the BTL (Bridge Tied Load) switches in. Now we are in monoblock mode, the 2 x PA-10s deliver 300 Wpc into 8 ohms. Yes, the extra power adds weight when there is deep bass. The 4th movement of Adam Fischer’s Mahler 1 goes deeper and has a more powerful effect.
Even more noteworthy is a further increase in precision and control that comes with an increase in realism. There is also greater dynamic freedom, the double PA-10 tracking swings more easily and maintains a slight richness. A single PA-10 is two big steps ahead of the AX-7e’s sound. Doubling up takes things a good step further. The benefits of mono mode are easy to hear. Although we switch back to stereo in an unusual way, we don’t feel disappointed.
With Cambridge Edge NQ
Essentially, the Edge NQ is a larger DS-10, but with analog inputs. The in-house dance partner is Cambridge’s 100 wpc Edge W power amplifier (£ 2500). That doesn’t mean we can’t hook it up with another manufacturer’s power amplifier.
On a visual level, pairing the Cambridge with the PA-10 is a dog breakfast. Individually beautiful, together they are Rocky and Bullwinkle. In terms of sound, it works really well: an even larger soundstage than the DS-10 on Color of Noize, also more dynamic. Sarah Jarosz sounds even more natural. Stephen Stubbs’ playing is positively crystalline, but with no edge of sound. It is a very palpable sound, the “being there” quotient raised a good level or two. The result? The PA-10 clearly shows the differences between the DS-10 and the Edge NQ.
The PA-10 is impressive whether in stereo or monoblock mode. With the right DS-10 preamplifier, it is a 2 (or 3) box solution, the performance of which exceeds the expectations set by the size. The recently announced PSU-10 Evo power supply for the DS-10 (1,100 euros) would increase the number of boxes to four.
Equally at home in a mixed environment, the PA-10 features Cambridge Audio’s Edge NQ. It even worked fine with a £ 400 Schiit Jotunheim headphone / preamp that I tried, if only briefly. The sound of the Gold Note power amplifier does not attract our attention in a noticeable way. His strengths are revealed through prolonged listening, especially the ability to provide plenty of detail while maintaining just the right amount of soul.
Aside from the Klipsch Forte III – a speaker that loves or hates it – I got the Gold Note PA-10 hooked more than anything else I’ve reviewed for Darko Audio. I didn’t think a simple power amplifier would do that. Bellissimo!
Further information: Gold Note