Tried and true: The Manley 500 and 250 Watt Monoblocks are our most powerful push-pull production-models. Both the circuit design and the selected componentry have been refined over years and years of development. Reliability that you can depend upon combined with musical accuracy and emotional authority is what these amplifiers promise- and deliver.
They are able to switch operation modes allowing the listener to choose between the sonically seductive qualities of triode and the more powerful tetrode configuration. We use big, beefy reservoir capacitors in the high voltage supplies giving plenty of instant energy for dynamic performance of transient peaks and bass impact and weight which often exceeds that of rival solid-state amplifiers. We run high voltages on the plates of the output tubes but operate them at lower current which will result in their longer life.
To avoid a heavy power drain when the cold amplifier is first switched on, we conceived a "Soft-Start" mode which also functions as an "Ever-Warm" position allowing the amplifiers to be always warmed up for pleasurable listening. Although each output tube has its own bias-adjust. we carefully fit each amplifier with computer-batched tubes for optimum performance.
We added a front-panel mute switch and created a new angled-back chassis to make it easier to hook up the interconnects, speaker cables, and IEC power cord.
In our own in-house magnetics department, our R&D team completely redesigned all of our output transformers in 1998 with the goal to reclaim that luscious rich mid-range of our vintage designs. We also specifically set out to achieve a deeper bottom register at higher power with lower distortion. Hours and hours of listening tests, measurements, and fine-tuning brought an exciting and stunning result to our ears. We hope you will agree.
Features and Specifications
- ALL-TUBE monoblock design 10 x KT90 or 6550C output tubes
- High current double 12BH7EH Electro-Harmonix Russian driver stage
- 12AT7EH large plate Electro-Harmonix Russian input tube
- BALANCED & UNBALANCED inputs
- MUTE switch
- TRIODE / TETRODE switching
- S0FT-START/ EVER-WARM standby mode
- MANLEY Precision output transformer
- Factory set for 5 ohms nominal
- Front panel bias measurement and adjust (hiding under the black insert)
- Large filter / reservoir capacitors 3800uF x 2
- Angled rear of chassis provides for easy connections
- WBT binding posts
- Input sensitivity: 1V
- Gain: 32dB tetrode; 30dB in triode
- Input Impedance RCA: 116 Kohm @ 1KHz
- Input Impedance XLR: 270Kohm @ 1KHz; 20Kohms @ 20KHz; 38Kohm @ 20Hz
- S/N Ratio: -80 dB
- Dynamic Range: 96dB
- FLAT frequency response: 10 Hz - 30 KHz continuous
- Power Consumption: 30 Watts in "EVER-WARM"
- Full power (tetrode): 500W
- Full power (triode): 275W