Another brilliant design from Mitch Margolis features a quartet of EL34 or 6CA7's in a fully differential circuit topology, including the input and driver stages. This 100w Snapper can be driven fully balanced all the way through via the XLR inputs. If you have balanced outputs on your preamplifier, this amplifier is the first Manley design to really let you take advantage of your XLR's without additional balancing input circuitry or input transformers. Very cleverly, the unbalanced RCA's can alternatively be used in this special topology with equally impressive results.
Biasing is easy with all measurement points and trimpots located on the top deck and speaker connection is made with heavy duty WBT binding posts.
Over three months of prototyping in the Manley Magnetics department resulted in a brand new output transformer design, a true 19-section incredibly complicated piece. The Snapper will crank out 100 watts at 10 cycles all day long and a full 110 watts from about 15Hz all the way up to 40KHz. Don't let frequency response specs fool you when people give you amazing bandwidth measured at... oh, five puny watts. Manley is talking full power bandwidth here! Continuous duty. Real muscle.
- 100 Watt partial triode (UltraLinear) EL-34 output stage is tolerant of a wider variety of output load conditions than pure pentode.
- Precise and balanced signal path from input to output. Circuit self-balances with either single-ended or balanced inputs. [Don't let either speaker terminal contact chassis, earth or any other ground.
- Switch-selectable RCA unbalanced inputs, or XLR balanced inputs. RCA jack input impedance about 330 kOhms, XLR 15 kOhms. If one input is not occupied, the input selector switch may then be used as a poor-man's MUTE switch. Handy for checking the bias, swapping input cables, etc..
- Input Sensitivity RCA jack: 750 mV RMS for full output into 5 Ohms
- Input Sensitivity RCA jack: 71 mV RMS for 1 watt output into 8 Ohms
- Input Sensitivity XLR jack: 1.5 V RMS for full output into 5 Ohms
- Overall voltage gain RCA jack to Output: 31 dBu, or about 32 volts per volt.
- Signal to A-weighted noise ratio on Humberto's bench is about 110 dB.
- Damping Factor: 4.7
- All-balanced amp topology keeps B+ voltage variations from degrading the performance of the input and driver stages. This technique can help make a push-pull amplifier very revealing of signal detail, in part by canceling power-supply-related perturbations and increasing signal-to-noise ratios.
- Portly 180 Joule energy storage reservoir in the main B+ supply channel for explosive transient response and athletic musical stamina. Also reduces B+ fluctuations due to varying current demands of output stage.
- Wideband transformerless balanced input with bridged 15 kOhm input impedance. Balanced input sensitivity may be selected by changing one resistor to suit whatever operating level may be required. 0 dBu, +4, +8, etc... If desired, the user may safely ground either pin 2 or 3 for single-ended drive of the balanced XLR input... [Be careful NOT to drive pins 2 and 3 of the XLR with a large common-mode signal, or the internal B+ fuse could blow.]
- Quiet DC supply for the input and driver tube filaments.
- Excellent square-wave response, and very low excess phase-shift with frequency.
- Amp actually puts out 110W @ 5 Ohm load @ 2 kHz @ onset of clipping, 117 VAC mains voltage, 3.5 amps mains current.
- 100 W spec: 15 Hz - 40 kHz into 5 Ohms
- Puts out 100W into an 8 Ohm load.
- Input Impedance RCA: 475 kOhm
- Input Impedance XLR: 15 kOhm (or 600 Ohm switchable on units before MSN524)
- Input Sensitivity RCA: 750mV input = 110W output
- Input Sensitivity XLR @ 15 kOhms: 1.5 V input = 110W output
- Input Sensitivity XLR @ 600 Ohms: 2.4 V input = 110W output (w/600 Ohm source)
- Gain RCA: factory set for 31 dB; Range = 29.5 to 34.5dB
- Gain XLR: factory set for 25 dB
- Negative Feedback: factory set for 9dB of global NFB
- Maximum Output Power into 5 Ohms: 110 Watts (1.5% THD @ 1kHz)
- Maximum Output Power into 8 Ohms: 100 Watts (1.5% THD @ 1kHz)
- Signal to Noise Ratio Ref. 1W: Typically 90 dB A-WGT 20-20K
- Noise Floor: Typically 105V = -77dBu A-WGT; Typically 388V = -66dBu unweighted
- Will Scratch Your Floor: Use coins under pointed feet to avoid marring cabinetry. Try $2 coins if you are in upper tax brackets. The bargain performer would be 5c pieces. Paper currency does not function as well.
- Dynamic Range: 98dB
- THD+noise @ 1W: less than 0.1%
- Frequency Response at 110W full power: 15 Hz to 40 kHz FLAT
- Frequency Response at 5W into 5 Ohms: 10 Hz to 65 kHz FLAT, -3dB @ 100KHz
- Recommended Speaker Load: Optimized for 5 Ohms
- Actual Output Impedance: 1.5 Ohms
- Power Consumption (idle): 170 Watts
- Power Consumption (at Full Power 110W): 336 Watts
- Operating Mains Voltage: Factory set for 220-240VAC
- Input Vacuum Tube: 1 x 12AX7 Russian with 6CA7 output tubes; use 12AT7EH large plate Electro-Harmonix Russian with EL34 types
- Driver Vacuum Tube: 1 x 7044 or 5687 GE JAN NOS
- Output Vacuum Tubes: 4 x 6CA7 (or EL34 equavalent)
- B+ Voltage: 570V DC
- Output Tube Quiescent Standing Current: 30mA
- Set Bias for: 300mVDC measured across 10 Ohm cathode resistor
- Lamp type: White LEDs
- Fuse values & types for: MDL or MDA 2 AMP/ 250 Volt SLO-BLO size 1/4" X 1 1/4" B+ FUSE: MDA 1/2 AMP, 250 Volt SLO-BLO CERAMIC BODY size 1/4" X 1 1/4"
- Dimensions: 222 x 330 x 381mm (HxWxD)
- Shipping weight each: 17.2kgs