LM-88IA Vacuum Tube Integrated Amplifier
- Amplifier Type: Vacuum Tube Integrated Amplifier
- Circuit Design: Push Pull Class AB
- Power Output: 42W + 42W (Fixed Bias), 30W + 30W (Cathode Bias)
- Tube Complement: 2 × 6CL8A, 2 × 12BH7, 4 × KT88
- Output Transformer: Custom Wound Output Transformer
- Analog Inputs & Outputs: 1 × Pre In (RCA, L/R), 3 × Line In (RCA, L/R)
- Speaker Outputs: 2 Channel Stereo (L/R), 5 Way Binding Posts
- Taps Per Channel: 0 Ω (Common/GND), 4 Ω, 8 Ω, 16 Ω
- Operation & Control: Remote Controllable
LM-88IA Vacuum Tube Integrated Amplifier
Dual Bias Versatility, Boundless Musicality
The LM - 88IA is a Class AB push pull tube amplifier with KT88 output tubes. Its dual bias system switches between 42W fixed bias and 30W cathode bias modes. Hand matched 6CL8A, 12BH7 tubes and isolated Z11 core transformer provide versatile audiophile grade tube performance.
Electronic Specifications
- Power Output: 42W + 42W (Fixed Bias), 30W + 30W (Cathode Bias)
- Frequency Response: 20 Hz – 50 kHz (-1 dB)
- THD: 1% (1 kHz)
- S/N Ratio: 87 dB
- Input Sensitivity: Line: 180mV Pre in: 1000mV
- Input Impedance: 100 kΩ
- Output Impedance: 4 Ω, 8 Ω, 16 Ω
- Power Requirements: ~ 115 V/120 V/220 V/230 V/240 V ±5% (50 Hz / 60 Hz)
- Tube Complement: 2 × 6CL8A, 2 × 12BH7, 4 × KT88
- Power Consumption: 250 W
- Working Conditions: Temperature: 0 ℃ – 40 ℃; Moisture: 20% – 80%
- Storage Conditions: Temperature: -20 ℃ – 70 ℃; Moisture: 20% – 90%
Weights & Dimensions
- Dimensions (W × D × H): 436 mm × 366 mm × 220 mm (17.31" × 14.41" × 8.66")
- Net Weight: 30 kg (66.14 lb)
Application
- Daily leisure: Vinyl records, Hi‑Fi music appreciation, background listening
- Home audio: High‑fidelity home listening room, dedicated audio corner
- Audiophile session: Music appreciation gatherings, record sharing parties
- Work & creation: Music production evaluation, audio tone reference
- Relaxation time: Late‑night listening, quiet immersive music enjoyment
Design
- Type: Vacuum‑tube integrated amplifier
- Chassis: Sturdy metal chassis, classic retro layout
- Transformer: Hand‑wound EI output & power transformers
- Tube complement: Swappable vacuum tube sockets
- Construction: Point‑to‑point hand‑wired build
- Finish: Brushed metal
Analog Inputs & Outputs
- 1 × Pre In (RCA, L/R)
- 3 × Line In (RCA, L/R)
Speaker Outputs
- 2‑channel stereo (Left / Right), 5‑way binding posts
- Taps per channel: 0Ω (Common/GND), 4 Ω, 8 Ω, 16 Ω
One‑year warranty for the complete unit, and six‑month warranty for vacuum tubes.
Products purchased online or from authorized local dealers and still within the warranty period are eligible for warranty service upon presentation of a valid purchase receipt.Purchases made from unauthorized dealers are NOT eligible for warranty service.
Call us: (+852) 8480 1098
Email : info@lm-audio.com
KT88 Class AB Amplification with Dual-Bias Mode Switching
Delivering up to 42 watts per channel, the LM-88IA operates in a refined Class AB push-pull topology with KT88 output power tubes, paired with 6CL8A and 12BH7 input tubes in the preamplifier stage. A defining feature is its selectable dual-bias system, allowing you to toggle between fixed bias and cathode bias operation:
Fixed Bias Mode:
Delivers 42W per channel with a warmer, lusher tonal character that approaches the smoothness of Class A operation, ideal for intimate vocal and acoustic recordings.
Cathode Bias Mode:
Runs at 30W per channel with greater stability and simpler maintenance, offering a crisp, well-defined presentation for upbeat and dynamic music.
Premium Transformer System with Isolated Encapsulation
At the heart of its performance lies a custom engineered transformer set, optimized for ultra low noise and extended frequency response:
Z11 Core Toroidal Power Transformer
Custom built toroidal power transformer utilizing premium Z11 silicon steel core. It delivers clean, stable power with minimal magnetic leakage, sustaining consistent performance at every volume level.
Audio Grade EI Output Transformers
Dual wide bandwidth EI type output transformers engineered to high end audio standards. Offering outstanding linearity, they faithfully preserve the full dynamic range and tonal signature of KT88 output tubes.
All transformers and chokes feature individual encapsulation and segregated mounting. This design greatly suppresses mutual electromagnetic interference, yielding a blacker noise floor and exquisite micro detail retrieval.
Hand-Selected Name-Brand Tubes with Precision Matching
Every tube in the LM 88IA is sourced from renowned audio tube manufacturers and undergoes strict quality screening before assembly. The factory configuration features 12BH7 tubes, 6CL8A tubes and KT88 power tubes, each chosen for their proven sonic character and reliability. Both preamplifier stage and power stage tubes are hand selected and precision matched for consistent electrical parameters across left and right channels. This rigorous matching protocol ensures uniform channel balance, accurate soundstage imaging and optimal sonic performance.
Comprehensive Connectivity with Dual-Mode Flexibility
The rear panel is equipped with a complete set of connection terminals to accommodate diverse audio systems:
- 3 pairs of RCA line-level inputs for connecting multiple source devices
- 1 pair of Pre-in terminals
- Heavy-duty speaker terminals supporting both 4Ω and 8Ω loudspeakers
The dedicated Pre-in input enables the LM-88IA to operate as a standalone power amplifier when paired with an external preamplifier, adding remarkable flexibility for system upgrades and custom hi-fi setups.
Dynamic & Versatile Sonic Performance
In its stock configuration, the LM-88IA delivers the classic KT88 sonic signature — powerful, controlled low end, rich midrange texture and open, extended treble. Thanks to the dual-bias design, it can shift between warm, immersive Class A-like tonality and crisp, punchy dynamic performance on demand. It excels across a wide range of genres, from large-scale symphonic classical and classic rock to vocal jazz and modern pop, making it a highly versatile centerpiece for any home audio system.