Hi everyone,
You are looking at a very rare MODDED CUSTOM MODIFIED GOLDEN SEAL LG-86HA "SOVIET" 4W HIGH CURRENT ORIENTED HEADPHONE AMPLIFIER AMP 220-240V.
In very good working condition, minor external cosmetic marks. As it's a current oriented amp, I would recommend planar magnetic headphones for this one.
It is fitted with a upgraded Gold-plated Copper 6.3mm headphone socket.
1 input: RCA.
2 outputs: 6.3mm headphone, 3.5mm headphone.
Item will be dispatched after payment clears, usually 2-3 working days.
Free Royal Mail Special Next Business Day delivery, sent via Parcelforce 24 hour delivery if over 2KG.
No collection possible, I also update the tracking details after dispatch.
Please check out my other items I may have for sale, thanks for looking : )
Genuine buyers only otherwise you will be reported to the authorities. I will make a note of the serial number for security purposes.
16x Burr-Brown 0112 AB736 opamps (8 per channel)
2x Burr-Brown 9536 34549 opamps (1 per channel)
23 position 100k series stepped attenuator
2x LM7815 discrete variable linear voltage regulators
10x Kemet 35V 470uf capacitors for power filtration, 4700uf total
2x Elna & 4x Nichicon Fine Gold capacitors on the amp board
OPA2111 high precision monolithic dielectrically isolated FET opamp
2x LME49600 high current headphone buffer
OPA445 high voltage FET-input opamp
NE5534
Transformer value 230V to 18V 100mA
Golden Seal OPA2111 + LME49600+ Golden Seal OPA445 High current fully balanced pre-stage power amplifier board, LG86HA
Golden Seal OPA2111 + LME49600 + Golden Seal OPA445BM High-current fully balanced preamplifier board and power amplifier board. Mono and stereo require 2 pieces.
Used for pre-balanced amplification, driving balanced high-impedance headphones, BTL power output to push high-sensitivity speakers to meet the various needs of audiophiles.
This board balances input and output, and is a current amplifier.
The power is 4-8W, the power is different for different loads.
The board needs to be used in conjunction with the pre-voltage amplifier board.
Discrete component balance front stage, op amp balance front stage, electronic tube balance front stage, transformer reverse phase drive front stage can be used.
This circuit has a servo circuit, and the left and right output midpoints are determined by the chip accuracy, which is safe to use.
LME49600 is an audio buffer chip. Its function is similar to the common driver-level transistors in amps.
It has the function of current expansion and can provide 250mA of current, providing powerful driving force for 16 OPA445BMs.
16 US OPA445BM gold-sealed single op amp ultra-low distortion BTL power output, 16-mouth OPA445BM ultra-low distortion amplification (single op amp distortion THD% 0.00003), 16 US gold-sealed single op amp parallel output, ant The work of gnawing the bones maintains the excellent performance of 16 single ops in the small signal ultra-low distortion.
The high-level design ensures that the whole machine has unique and extraordinary characteristics.
It is outstanding, pushing 8 ohms to 600 ohms headphones or 8-16 ohm high sensitivity speaker speakers.
This circuit board is powered by ±15V, has a wide sound range, high resolution, rich details, strong driving force, and balanced tone.
Compared with the 10,000 yuan headphone amplifier on the market, it is not inferior at all, and its performance is better than ordinary amplifier circuits.
Material: high-quality double-sided glass fiber board (127×70mm), imported resistance-capacitance component assembly.
Japanese "KOA" 1/4W high-precision 5-color ring metal film resistors (the error is far less than 1%), Japanese ELNA audio Gold electrolytic capacitors, US OPA2111 Gold-sealed operational amplifiers, US national half LME49600, US OPA445BM, 4 imported 1U50V Ultra-small stepless film capacitors, Gold Nikon electrolytic decoupling, 2 Gold-plated hole IC sockets for easy upgrade.
LG86HA finished board
Golden Seal OPA445BM is a field tube input type beautiful sound single op amp, low frequency strength and treble extension are in place, large dynamic swing, maximum output Vp-p: 110v, promote common 6P14, 6P6P, 6P3P, KT66, EL34, KT88
It's easy to wait, and it's no problem to drive the vacuum tube with deep negative pressure on the 2A3/300B grid.
Working voltage: ±10V-±45V
Output current: ±15mA, short-circuit output 26mA
Distortion THD%: 0.00003
Common mode rejection ratio: 95DB
Voltage conversion speed: 15V/μs
Broadband gain product: 2MHZ
Input offset voltage: ±1MV
Voltage noise density: 15nV/√Hz
Friendly reminder: This power amplifier board is a dual-channel power amplifier board, which needs to be used with the supporting pre-amplifier board.
The gold-sealed op amp on the circuit board is a genuine second-hand disassembled machine.
Due to the different batches of purchases, there are Thailand-made, American-made, and American-made op amps without USA marks.
They are all products of American AD company and are not selected.
Installing the same board will pick the same specifications or the same origin assembly.
The principle of ultra-low distortion is like singing in a chorus.
Everyone sings in unison.
As long as everyone's throat is easy to pronounce and keep singing in the best volume area, everyone's vocal volume will be overwhelming and majestic, as if it is the sound of nature!
It is also like the parallel operation of dozens of pairs of high-power tubes in the power amplifier, which can increase the output current, reduce the internal resistance, improve the damping, and reduce the distortion.
It is also like connecting dozens of speakers of the same specification on a giant floor-standing flagship speaker, so that each speaker can work in the area with the best linearity and minimum distortion to achieve a certain sound pressure level, which solves the problem of a single speaker at high volume. distortion.
The parallel output of 16 OPA445BM op amps is also the same, there are similarities in the same way!