Though the WooAudio6 is a very good amp for the price, people are constantly looking for ways to upgrade its performance. One way to upgrade the WooAudio6 is by replacing the stock rectifier to the Sophia Princess Rectifier, which WooAudio sells for $150.
It may come with a cheap looking packaging, but the Sophia Princess tube is an awe to behold. It sized much bigger than the stock Tung-Sol rectifier and it’s really a piece of art made from glass and metal. When turned on, the tube lights with a beautiful V-shaped pattern. It’s really mesmerizing. Even if it yields absolutely no sonic improvements, some people (me included), would happily pay $150 just so my amp can look better. (Fortunately, the WooAudio6 is not mine) For people who’s serious about audio, the question is, how much better does the Sophia Princess rectifier perform from the stock Tung-Sol? Having both tubes in our review room, I gave both a listen.
This WooAudio6 comes with the PDPS upgrade from WooAudio, and it’s already a very fine amp to begin with. However, I really wouldn’t compare it to other amps in the $1,000+ range, as the WooAudio6 can’t compete with the higher priced amplifiers in terms of refinement, details, imaging, et cetera. With the Sophia Princess rectifier, you’re not changing the sound signature of the WooAudio6. After all, why mess with such a great musicality? The Sophia Princess rectifier, however, takes the stock WooAudio6 and adds a level of refinement normally only found on more expensive amplifiers.
The soundstage is improved, and not only does the Woo sounds more open, but its imaging is also significantly improved. I really like the imaging performance of the WooAudio6 with the Sophia Princess, so much that I find myself comparing it to the SPL Phonitor amplifier, which is a high-end solid state monitoring headphone amplifier with a superb imaging. Though the SPL Phonitor has a bigger soundstage than the WooAudio6, the Woo with the Sophia Princess gives a more pleasant imaging that’s both intimate and yet well separated.
Ambience, subtle nuances, and decay also sounds more natural and real. Even though I didn’t notice any improvements in detail level, these improvements brought by the Sophia Princess makes the experience more engaging and real. Having listened to the Sophia Princess, I also feel that the low bass bump that I associate with the WooAudio6 is actually caused by the Tung-Sol rectifier, and is now eliminated by using the Sophia Princess. Bass extension is now smoother and more natural.
Having heard the Sophia Princess, now the same amplifier with the Tung-Sol rectifier sounds very closed and congested. It’s really hard to go back to the stock rectifier. I also think that the $150 spent on the Princess is well worth the upgrade, as now the WooAudio6 feels more like a $1,000 amplifier, and it hangs pretty confidently next to the Phonitor, the Auditor, the Grace, and the Beta22.
System for auditioning:
Headphones: Sennheiser HD800, AKG K501, AKG K701
Source: MacPro via Toslink to Lavry DA11, CEC TL51XZ via Coaxial to Lavry DA11
Amplifier: Lavry DA11, Grace m902, WooAudio6 with PDPS and Sophia Princess, SPL Auditor, SPL Phonitor.
Interconnect: Transparent Musiclink Plus XLR, Purist Audio Design Maximus XLR, Stereovox Digital Interconnect, DIY Copper with Eichman Bullet RCA