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Soo In Chae from Korea's Bakoon Int'l: "The Satri circuits are the same but overall construction and parts choices between the two Bakoons—from small diodes to big transformers to power supply design like the battery supply (for our future converters and phono preamplifiers or already for existing products from other firms)—are all different. You could say that our products are more modernish inside and out than the Japanese equivalents. And yes, a DAC is in development. We plan to introduce it together with new high-power amplifiers. Hopefully this might be within the year." Soo In then relayed my remaining technical questions to designer Nagai-san in Japan.
Exicon 10N20/10P20 output transistors for one channel

Akira Nagai: "The AMP-11R has a single voltage gain stage. The Satri-IC takes care of this since its gain level is determined by the ratio of input to output resistors (A=RL/L). Voltage signals from conventional sources incoming over RCA are converted to current by a Jfet buffer before entering the Satri-IC (which is current input/current output). This input buffer converts impedance but adds zero gain. The push/pull class AB output stage is based on lateral Exicon Mosfets. Because those provide no additional voltage gain either, the ultra-wide bandwidth and low noise of the Satri-IC are barely affected. This results in the very same high performance of our proprietary gain stage even at the binding posts past the output current buffer.
Headphone gain jumpers - medium as delivered*
[pins 1+2=high, 2+3=medium, open=low]
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* With Burson's DA-160 converter set to +6dB, HifiMan's notoriously inefficient 50Ω/83.5dB HE-6 planarmagnetic headphones with 3-meter Entreq leash already played louder on the AMP-11R's medium gain setting than I could tolerate. Standard 2V sources plus hi-gain mode will drive any commercially available headphone to all desired levels. For details I asked Soo In Chae: "Headphones use the same Mosfet output stage except that impedance gets converted by a set of high-quality resistors via the jumper settings. These resistors make the 6.3mm output impedance 33Ω (high), 56Ω (medium) and 89Ω (low gain). To calculate the gain level of the headphone output, use this simple formula: Ghd = Gsp x {Hdz / (Hdz+R)} wherein Ghd = headphone gain level, Gsp = speaker gain level (given as 20dB max), Hdz = headphone nominal impedance and R = headphone output impedance. For example, using the 'high-gain' setting with a 50Ω nominal headphone factors to 20dB x 50 / (50+33) = 12.05dB max. The power ratings are a bit more complicated. I'll just give you the final numbers for your requested nominal headphone impedance values using only the high-gain setting: 38Ω = 1.81 watts, 50Ω = 1.74 watts, 300Ω = 0.65 watts and 600Ω = 0.36 watts."
The stand's trays with receiver dimples are decoupled to provide lateral play for physical isolation


Satri IC EX

"The outboard power supply contains a good amount of chokes. This means the circuit becomes a CLC filter to remove the AC noise of 50Hz/60Hz. You can expect all the other usual benefits as well such as separation of heat, vibration, magnetic fields etc. that may harm the main amplifying circuit's performance. The bandwidth of the Satri-IC is determined by its bias current. The higher the bias current, the wider the bandwidth. Because the current signal is not limited by any other factors, there is no slew rate or need for negative feedback. Hence the signal is never returned to the input and suffers no time-domain degradation.


"These factors result in the stability and performance of the Satri circuit. The design goal of the AMP-11R was to provide the highest performance in a simple system. The removal of the remote controller and input switching circuit created more benefits toward this goal while sacrificing only a little convenience."


Use is as simple as connecting the 3-pin umbilical between both chassis; one standard power cord between power supply and wall; one standard RCA interconnect between main unit and source; speakers or headphones (inserting the latter auto mutes the main outputs); then flicking up the power mains on the left cheek of the main unit (the power supply is always on) and slowly opening the finely stepped volume wheel at the right corner. The tiny power LEDs beneath the fascia logos will glow orange for the black units, a classy white for the silver versions and nicely reflect off the mini rack's tiers. That's when one encounters the Bakoon sound for the first time. Would that bring home the bacon?