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Nova M-34
The Nova M-34 is the North American version of the Asian M-9SE but in only one color option: black. (If you really want silver or gold, Bernard will process a special order. Ditto for the Pre-2.) Each mono occupies approximately 11" x 13" of real estate and weighs about 40 lbs. The same over-sized aluminum footers with shock-absorbing pellets as the Pre-2 make sure the amp sit snug and tight. The mirror-finished stainless steel chassis contrasts with black aluminum panels front and back, measuring 100mm and 50mm thick respectively. .

With or without tube cage, the frontal view is symmetrically balanced but never looks dull thanks to the "raised collar, dropped shoulder" fascia contour that breaks with uniformity and proudly exhibits the three-dimensional die-cast bronze Audio Space badge on the collar. (Our gold or silver-paneled Asian counterparts only get two-dimensional silk-screen branding. But they get the smarter flat-head torpedo dial knobs and we get the boring flat ones. Anyway, I think Bernard would be happy to offer those on special order too - wouldn't you, Bernard?) Below the badge, the circular multi-purpose VU meter is flanked by polished chrome knobs and toggle switches on either side, with a 6-step meter range select and Triode/Ultralinear toggle on the left, a 6-step Negative Feedback adjust and 0°/180° phase toggle on the right.

The stainless steel platform sports all Audio Space branded Chinese tubes. Three MTs, one 12AX7 and two 12AU7 head up the primary and driver stage. Behind that, four EL-34s work in class AB push-pull to deliver 60 watts in ultralinear mode or 32 watts in triode. Those are the nominal output figures, which could max out to 78/45 watts respectively. (Audio Space also offers the Nova M-88, a higher-power KT-88 version.) In front of each output tube, a tiny hole allows insertion of a flathead screwdriver to adjust the bias voltage. The process is facilitated by direct needle reading of the analog VU meter when you dial the meter range select knob through the four output tubes.

The top scale on the VU meter is calibrated for output level in dB, the lower one for bias current from 0 to 100 (100 = 100mA) and the recommended setting is 30mA marked for an obvious reminder. (The lower photo shows the needle overlapping the 30mA mark.) In case you prefer the old-fashioned accuracy of a multi meter, the probing points are conveniently located adjacent to the tube sockets. I checked the accuracy of the VU meter against my digital multi-meter and confirmed that the built-in meter is trustworthy.

At this point, I should point out that in the instruction manual, users are advised to set the bias current to 30mA. While technically correct, that might be confusing to some because on the chassis next to the bias probing points, the silk screen indicates "DC: 0.3V". Standard industry practice is to convert bias current to bias voltage through a 10 ohm resistor so that it's safely measurable. Hence 30mA x 10ohm = 300mV is the recommended bias voltage. If you use a multi meter, set it to DC mA reading and probe the voltage points for a current reading, you'll get nothing - and that's unsafe because you're shorting the circuit. So a word of advice: forget the 30mA business in the manual and stick to 300mV when using your own meter.

Both power and output transformer are proprietary Audio Space designs and manufactured in-house from the hand-winding of the cores to the multi-coat spray paint to ensure low electromagnetic emission, wide frequency response and aesthetic QC. On the back panel are your usual IEC receptacle and four-tap speaker binding posts for 4/8/16-ohm load. The unusual feature are the bi-wirable doubled-up RCA input sockets to parallel interconnects of different flavors. The mains switch is located on the left panel towards the rear, close to the IEC and beneath the power supply transformer for shortest wiring. Peeping inside, the layout appears in spic and span point-to-point hardwiring, with only two small PCBs for bias adjustment.

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Like the Pre-2, the monoblocks also sport the Audio Space proprietary choke coil and high-end coupling caps, plus large capacity Nichicon DC filter caps, metal film resistors, ceramic tube sockets and a generous supply of Teflon-insulated pure copper or pure silver wiring in critical junctions. Stated frequency response is 20Hz – 40KHz (+/– 0.5dB). S/N ratio is better than 90dB and hum less than 2mV/8Ω, quite impressive for tube amps.

For more images on the monos, refer to Sidebar 3.