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Reviewer: Srajan Ebaen
Source: Zanden Audio Model 2000P/5000S
Preamp/Integrated: ModWright SWL 9.0SE; Music First Audio; Hyperion Sound BEC-P25T

Amp: 2 x Audiosector Patek SE; Yamamoto A-08S; Canary Audio CA-308s; FirstWatt F3 [on review]
Speakers: Zu Cable Definition Mk 1.5 Pro version with Rane PEQ-55; Gallo Reference 3
Cables: Zanden Audio proprietary I²S cable, Zu Cable Varial and Ibis, Zu Cable Birth on Definitions; Stealth Audio Cable Indra, MetaCarbon & NanoFiber [on loan]; SilverFi interconnects; Crystal Cable Reference power cords; ZCable Hurricane power cords on both conditioners
Stands: 1 x Grand Prix Audio Monaco four-tier
Powerline conditioning: 2 x Walker Audio Velocitor S
Sundry accessories: GPA Formula Carbon/Kevlar shelf for transport; GPA Apex footers underneath stand, DAC and amp; Walker Audio SST on all connections; Walker Audio Vivid CD cleaner; Furutech RD-2 CD demagnetizer; WorldPower cryo'd Hubbell wall sockets
Room size: 30' w x 18' d x 10' h [sloping ceiling] in long-wall setup in one half, with open adjoining living room for a total of ca.1000 squ.ft floor plan

Review Component Retail: $1,750

When Hyperion Sound's low-key sales manager Albert Wu confided one day that their remote-controlled four-valve preamplifier was perhaps the best product they'd authored yet, my ears pricked up. After all, their HPS-938 loudspeakers and HT-88 paralleled SET monos had both won Blue Moon Awards from me for excellent sonics at very fair pricing. This made their new-for-2006 HT-845 monos (25 watts of 845 SET power with 850 volts on the rails and a $4,600/pr retail) look at least on paper all set to continue Hyperion's short but already mighty powerful tradition of high-value excellence.
If a $1,750 tube preamp with full creature comforts could now be better yet in its category than the already reviewed products had proven to be in theirs, someone had to go to town. Wake up the blissfully ignorant sleepers and rattle a few cages. So I offered my free services. Naturally, I was hoping that whatever I'd eventually shout about would be good news. Such are the insecurities of review assignments. There's assumptions going in. Those are based on track record or prior personal exposure. But nothing substitutes for personal tests. Nothing. Would street cred, industry rep and in-home audition coincide again as they had before? Only one way to find out.
Under its substantial silver-anodized cover, the BEC-P25T exhibits discrete heavy-duty architecture. The power mains supply is shielded from the core circuits behind a solid metal divider. The "precision tracking" volume control occupies its own board and is then split, with the motor-driven shaft remotely synchronized on the output board. Separated on their own boards as well are the capacitive storage bank with its eight custom chokes for ultra-clean power management; and the SRPP tube output stage with its oil-filled caps bypassing the Hyperion-branded metallized coupling capacitors. Two 12AX7s with x 30 gain and two 12AU7s with x 15 gain can be optionally made all the same to raise or lower the circuit's overall voltage gain. SRPP is an anode follower with a constant current source instead of resistance as the load. The constant current source provides higher impedance for higher gain; helps reduce power-line noise and hum; and doubles as cathode followers to provide low output impedance.

The Tube CAD Journal Vol. 2 No. 4 [May 2000] explains it as follows: "This circuit has many names: SRPP, SEPP, Totem Pole, Mu Follower, Mu amplifier, Cascoded Cathode Follower and its original name, the Series-Balanced amplifier (Feb. 1943, US patent 2,310,342.) Just what SRPP means is uncertain. Maybe it stands for Series Regulated Push-Pull or Single-Ended Reflexive Push-Pull amplifier. Essentially, one triode stands on top of another with a resistor spanning cathode and plate. The bottom tube receives the input signal and its reaction to that signal drives the top tube whose cathode provides the output signal. An SRPP circuit thus functions as a push/pull output stage that includes its own phase splitter and hence requires Class A operation.
As the current flowing through the bottom tube varies, the resistor Rak sees a varying voltage develop across its resistance in response. This variation in voltage is then given either through a capacitor or directly to the top triode's grid, which will conduct a varying amount of current as a result. Since the load resistance connects between the top and bottom tubes and ground, it provides a path to absorb the change in current."
Even more unusual at this price point is the fully relay-switched nature of the five inputs, whose selection is confirmed by a tiny blue LED above the corresponding ball-shaped control on the fascia. Another unexpected feature is the external grounding post.

Mute can be triggered remotely or manually and confirms via red LED. It's actually a double mute and a remote-triggered mute can't be undone manually but only by remote. A rear-mounted power mains engages stand-by which steps up to active status when the frontal power button is engaged and its tiny LED turns from red to green.
Specs for the BEC-P25T include a claimed S/N ratio of >100dB, distortion of < 0.03% and frequency response of 5Hz - 200kHz. This indicates the thoroughly modern aspiration Hyperion's engineers pursued with this preamp. Regulated power supplies with a total of six high and low-voltage regulators combine with a choke-filtered mains supply and high-energy plate supplies and individually regulated DC supply for each tube. And this preamp is pretty hefty in response to the internal parts density - 22 lbs of compact weight.
Squeaky-clean power management was foremost on the engineer's mind and Hyperion takes extra pride in this aspect of the BEC-P25T. "According to our Singapore dealer, he has never seen a better power management design," added Albert. The second core consideration was how to provide the cleanest, most accurate volume control while avoiding dual-mono knobs with their synchronization issues. Hyperion's solution is unusual. The frontal knob (or a remote command) triggers the separated remote shaft, incurring a minor delay in motor response for " isolated precision tracking and the shortest signal path for the most accurate volume control."

About the pricing, Albert punned that "as always, I laughed when I heard the MSRP from my manager. Sometimes even I wonder what the heck we are doing this business for." To make trouble, I'd say - and rebalance the out-of-whack scales of HighEnd audio pricing where individual components cost more than most people spend on a used car. This is the sort of product that I get the most personal satisfaction writing about. After today's obligatory window-shopping pre-coverage of Hyperion Sound's BEC-P25T, this could be another one to watch out for and which the competition will only grumblingly acknowledge for its existence.

As it turned out, this particular assignment would find itself bedevilled by bloody ol' Murphy and his gang of gremlins. The preamp's first appearance had it show up with one channel not outputting sound though swapping tubes confirmed they were all happy. The visible connections to the output terminals seemed fine as well so I returned the loaner as something I couldn't trouble-shoot myself. When the same unit returned, it played beautifully for a while only for me to return from an errand one day to have my wife report that she smelled something funny and saw a huge cloud of smoke billowing over the piece shortly after I'd left. Popping the hood showed that one capacitor had given up its ghost in noxious fumes. Back to Hyperion it went. Yesterday, the same piece arrived for the third time, with the shipping box in apparently fine shape and nothing outwardly amiss with the innards. Alas, no sound. Removing the top cover now showed that both vertically mounted power transformers had tipped backwards to break off the circuit board pins and sever their little copper ground wires which had been soldered to said pins.

My prior Hyperion review loaners kicked royal arse and operated flawlessly to win awards. Hence I'm not quite sure what to think about these incidents. In the end, I'm inclined to write them off to some type of imaginary 'jinx'. How's that for a conspiracy theory? Alas, my patience on this three-strike deal has worn thin to the point of giving up. Accordingly, the review's herewith cancelled. My apologies to those readers who were patiently awaiting its conclusion.
Manufacturer's website