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Burson does agree. Even when dealing with high-quality discrete parts as their no-IC mantra has championed for both amplification and voltage regulation since day one, fewer parts sound better than more. It's not like a sandwich. There two slices of cheese are automatically better than one. Here they're proud to announce that the current-feedback FET input stage of their latest Soloist headfi/preamp—three years in the makings we're told—has brought their prior number of parts down to 21. This they view not as merely an abstract engineering achievement. They claim demonstrable performance benefits. The Soloist thus inaugurates Burson's new Musicians Series. It's not only - um, discrete from the popular 160 range. It sits above it. It's about less is more. "Each time a component is removed from the signal path, a veil lifts between us and the music. Therefore the design objective was to remove as many signal-path components as possible while still maintaining ideal operational conditions."
But it's also about more. Not so much money as features. The Soloist's class A single-ended so-called VOS or variable output stage introduces three gain settings for its 6.3mm headphone output. That covers from 0.18 to 1.8 to 4wpc/16Ω and as such accommodates high-sensitivity IEMs and low-efficiency planarmagnetics. In preamp mode the same feature generates from 7.7 to 14 to 18dB of gain. The taper of the 24-step attenuator too was redesigned to complement the VOS taper for maximal flexibility and control. The 6mm aluminum enclosure or vault has been improved. In signature Burson style it acts as one massive heat sink. This allows for high idle current (good for sound) and cooler direct-mounted transistors (good for longevity). The regulated power supply is new too.
"It's built around a new noise-filtering network that employs twice as many filtering stages over the previous design to result in superior noise rejection. That is fed by a new custom-built low noise transformer which delivers 35 watts of power with 9V and two 18V secondaries." Actual internal dissipation is 25 watts. Input impedance is 36.5KΩ. Output impedance into a 30Ω load (1 watt) is below 1Ω. Frequency response is rated ± 1dB from 0 - 50kHz.
Signal to noise ratio is better than 96dB,
THD into 30Ω/1w sits below 0.03%. The attenuator's channel separation is better than 73dB.
The 2 x four holes in the foreground of the circuit board below look at the output power transistors beneath it.
The two holes behind the red caps look at the power supply transistors instead.
The different gain settings are created with local feedback. Higher feedback in the voltage gain stage creates lower gain. Thus regardless of setting the actual output stage remains unaltered. Low-gain mode doesn't somehow 'switch out' some of the quad-paralleled transistors to decimate the stage. "No matter what gain level, the output stage's single-ended class A idle current remains an ideal constant. It delivers the same sonic performance at all gain settings. The Soloist also applies improved case construction. We did not make a big fuss about it on our website but we reduced the number of assembly parts and it looks even better now on the inside."
Here is a basic representation of the relationship between preamp gain and VOS power.
These facts establish the Soloist's positioning within Burson's catalogue and also the raison behind its d'être. A newly designed Fet-based input stage had advanced performance to a degree that warranted a new model. Presto, the first entrant of a new range still in the familiar compact overbuilt casing but now with simplified guts.
Something else got simplified too. On the front it's no longer Burson Audio, just Burson in a new font. "The name's Bond." Then silence. That's fame. No need for second names. Time for James to catch up.
How would performance manifest vis-à-vis the existing DA-160/HA-160 and HA-160DS? Easily heard next level up? How about German and Sino/American competitors?