For a brief time line of Shinobu Karaki's life, he was born in 1959 in Osaka. "As a boy, I hand-crafted electronics and loved to play guitar with a rock band during high school and university. My first DIY amp was a 12AX7 NF-type RIAA equalizer when I was 15 years old. I still play guitar, mainly Rock, Jazz and classical.

"My wife and I have two kids. Our daughter is a painting artist and my son is a network engineer at Sun Computers. From 1980-2009, I worked for Texas Instruments Japan Ltd and their US headquarters. I also was the technical sales account manager for Sony, Panasonic, Sharp and JVC, mainly for their consumer electronics segments. Then I was promoted to Digital AV R&D section marketing manager. My final position was as digital audio group business director to manage R&D, application support, marketing and sales.


"By 2009 I quit TI on an early retirement program to pursue my personal audio interest and design and build power amplifiers, D/A converters, audio selector switch boxes and such for local audiophiles and shops. That's when I began to use the Aurorasound logo and brand name. I still work for two Swedish and Korean audio engineering companies as technical sales consultant. I also work as guitar teacher for Seven & I Holdings.


"In 2011 I released Cada, a DHT DAC and preamp with a HiFace-Pro USB interface obtained under license from M2Tech. A year later I released the BusPower-Pro, a cleaner power supply for USB audio. I also visited with Lundahl in Sweden to commission a special coil inductor for my forthcoming Vida LCR-type RIAA phono equalizer which was released in 2013.


"That's also the year when I established Aurorasound Inc. as a limited company and moved to a new workshop and listening room away from our home. The Aurorasound team consists of myself, my wife and two contract engineers. We've participated at T.H.E. Show in Las Vegas, at the HighEnd Munich show and our domestic one in Hong Kong. In 2014 I released our Heada headphone amplifier followed by the Pada power amp a year later. For this year I'm developing a D/A converter and more. Currently we sell in 12 countries across Asia, Europe and the US..."

The Preda chassis are very solid 6mm construction except for the thinner rear panel and slightly thinner cover. Because of the solid centre divider to which the lid bolts, the already solid tops ring far less than usual.


Here we see how one does a balanced transformer attenuator - with quad transformers. If the Slagleformers are anything like what The Bespoke Audio Company use for their passives, this should equate to more than three kilometres of just autoformer wiring.

The rear panel layout avoids mirror imaging for "better performance". If you use uni-sleeve cables like Zu's Event which break out into rather short pig tails, you're spared not reaching the outer inputs. With the TBSP, the belly-mounted power switch resides on the power supply unit, the low-gain switch on the head unit. The former doesn't light up, the latter goes green. If you engage the balance control, a small green dot appears in the display, to the same side of the numerical readout as the channel you've manipulated. With more attenuation in that channel, that dot changes to light red, then dark red. Once balance is centred again, that dot disappears.


More material extras come with the enhanced connectivity panel and its related i/o boards (below we see just one channel). Four of the inputs are dual-function RCA/XLR with associated toggles to select mode of operation. These shouldn't have signal present in both modes at the same time. The XLR and RCA outputs are all simultaneously active.

Double trouble continues with discrete gain modules per signal phase.

This photo shows the stacked Slagleformer construction with the remote-triggered relays which switch the autoformer tabs on the top, the actual encased Slagles below.

The power supply adopts the same divide-and-conquer layout by also going dual mono with the central partition, then keeping supplies for the digital control circuits and analog modules discrete with their own boards and transformers (the inner boards are for the gain circuits). The nessessary 10-pin umbilical between PSU and head chassis is included. A mains cord is not.

There's no doubt whatsoever where your extra coin was spent.