
HD88
New Concept Tube Power Amplifier
Introduction to the Characteristics of Products
Innovative Circuit
1. The boot process is impact-free, gradually loading power over time.
2. Power tube automatic bias servo tracking control eliminates the need for user adjustmentthroughout the entire lifespan.
3. The new circuit design features an innovative quasi-symmetric configuration.
4. Minimal negative feedback is utilized in a short loop.
5. Low internal resistance drive between amplification stages ensures excellent high transientcharacteristics.
6. Complete isolation of high and low pressure, along with a highly efficient and fully regulatedpower supply, is implemented for high voltage applications.
7. A large dynamic gain-power matching design is employed.
Innovative technology
1. The innovative power tube's mellow audio processing technology improves the lifespan ofelectronics and enhances heat dissipation capacity.
2. The separator cover is coated with nano-graphene ceramic material, effectively converting heatinto far-infrared radiation to enhance heat dissipation.
3. Hybrid shed technology is a unique crafting technique.
4. Custom machine inner wires are used for their high temperature resistance, high pressureresistance, shielding capabilities, and super soft multi-strand silver-plated pure copper wire
composition.5. The special double-layer chassis structure features aerospace aluminum alloy panels withmultidimensional machining for the purposes of anti-vibration and anti-electromagnetic
interference.6. The power socket provides a safety guarantee to overcome EMI interference.
7. An advanced audio transformer with an independent double negative feedback structure isutilized.
8. Highly reliable electronic components are screened, including electrolytic capacitors that havehigh temperature resistance, long life, and low internal resistance.
9. Audio input/output interfaces are plated with non-magnetic rhodium to minimize signal pollution.
10. The front tube shield damper heat sink helps improve the signal-to-noise ratio and reducemicrophone effect.
Innovation function1. Vacuum tube amplifiers have multiple modes: integrated amplifier mode, mono-biamp mode, mono-wire mode, and mono-bridge mode.
2. Always ready and on standby, the power tubes in this amplifier feature a small currentpreheating mode, allowing you to enjoy the best audio at any time.
3. This amplifier has superb overload resistance and can handle a minimum 2-ohm load whenbridged.
Amplifier technical specification
Rated stereo output power:
60W per channel at 8 Ω, 20Hz to 70KHz, -3dB
Maximum undistorted stereo output power:
66W per channel at 8Ω,80W per channel at 4Ω, 1kHz
Bridge mono output power:180Wat 8Ω, 1KHz
Frequency range:
6Hz to 80KHz±1dB(at 1 watt into 8Ω) 0dB at 1KHz
Stereo power bandwidth:
20Hz to 65KHz -3db; 0dB=60W 1KHz, 8Ω
20Hz to 70KHz -3db; 0dB=50W 1KHz, 8Ω
7Hz to 73KHz -3db; 0dB=25W 1KHz, 8Ω
Total harmonic distortion:
Less than 0.3% at 1W output,20Hz to 20KHz,8Ω,typically 0.05% @1kHZ.
Less than 1% at 60W output,40Hz to 15KHz,8Ω,typically ≤0.8% @1kHz
Circuit model: Modified UL, Class AB1
Bias adjustment: Auto Biased
The amount of negative feedback: Less than 6dB
The Input Impedance: 25KΩ
Input Sensitivity: Max. 690mVrms at 1KHz for 60 watt output
Rated Output Impedance: 6Ω
Signal to noise ratio: 98dB (A weighted)
Tube service: 4 x KT88;4 x 6SN7; 2 x 6922
Machine size: 17(W) x 15(D) x 10 (H) inches
44 (W) x 37 (D) x 27(H) cm
Machine Weight: 79 lbs (36kg) N.W. 93 lbs (42 kg ) G.W.
Fuse: 220VAC,T3.15A,115 VAC,T6.3A
FRE-1W
FRE-25W
FRE-50W
FRE-60W
THD-1W
THD-25W
THD-50W
THD-60W
List of Tubes Used
This machine uses two 6922 vacuum tubes and four 6SN7 vacuum tubes for the front stage of amplification. The rear stage uses four Russian KT88 vacuum tubes for push-pull amplification.
TF* is Tube Fidelity Company's special pure thickness sound processing Tube, which has the effect of pure thickness and pure sound, eliminating noise, and improving sound quality.
Vacuum tube model for this machine
6922EH
6SN7EH
SVKT88 TF*
Alternative vacuum tube options
E88CC
6N8P,CV181
6550
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