Headphone Amplifier HIFI with Lehmann OPA2134PA High-grade Aluminum Chassis 16-600 ohms

Model No: WEIA-LM

The sound of this headphone amp with Sennheiser high-impedance headphones is obviously with German national aesthetic orientation, restrained and moderate. The longer you listen, the more you can comprehend its meaning. It's not like some equipment that makes one ear amazing. After the passion, it is either indifferent or fatigued.

It is like a flower bud in the early morning, as the sun rises, from the moment you start to listen, she slowly reveals her beauty. It is an amp that can amplify the characteristics of headphones without changing its style.

(Doesn't include the headphone, the photo only for your information)

Components characteristics

1. Japan Chemical LXZ high-frequency low-resistance capacitor; Its core operational amplifier adopts Texas Instruments OPA2134PA.

2. British WELWYN original resistance, 1% accuracy, 50ppm temperature drift, the effect is extremely stable, used in analog circuits, full-frequency balance is meticulous, wide bandwidth, moderate frequency texture, and no impurities in digital circuits Information, sufficient details, all copper pins ensure strong current carrying capacity. The details are rich and very delicate.

3. Japanese high-precision ALPS27 potentiometer, sound channel balance error-free, good hand feeling, long life. American CMC 24K gold-plated RCA terminal, oxidation resistance, low internal resistance, very good transmission performance. Original genuine Swiss Neutrik 6.35 gold-plated headphone socket Nutrick socket.

4. Original TALEMA (or porcupine) audio transformer.

5. The power amplifier transistors BD139-16 BD140-1 is used, which is different from the ordinary ST's ON BD139 140. They have better linearity, better sound quality, obvious effects and better levels.

6. Used high-grade aluminum chassis, solid aluminum knob also feel very good compact.

Details

Specifications

1. Input impedance: 47K ohm;
2. Frequency response range: 10Hz(-0.3dB)-35kHz(-1dB)
3. Adaptation impedance: 8-600 Ω
4. Distortion: <0.001% (6mW/300 ohms)
5. SNR: > 95 dB at 0 dB gain (analogue)
6. Channel separation: > 90 dB/10 kHz
7. Maximum gain:  0 dB, 10 dB, 20 dB (It is adjusted by the switch on the bottom of the unit)
8. Output power: 200mW/300 ohms; 400mW/60 ohms
9. Input interface: RCA
10. Output interface: 6.3mm phone jack interface × 2, RCA interface
11. Power consumption: about 10 W
12. Operating voltage:. 220V/50Hz
13. Size: 280x110x44mm
14. Weight: 2.1 kg
15. Accessories:

           Power cord x 1

Diagram circuit for your information

About usage

1. First of all, you must understand the correct usage habits of the audio system. When the amp is off, the volume knob is turned to the minimum position, first turn on the sound source, then turn on the amp, and then gradually increase the volume, so as to avoid the impact on the headphones at the moment of turning on.

2. New equipment has a burn-in aging process. It is recommended that the new machine should be burned in. Generally, it can enter a better state in 2 to 3 weeks.

3. Operational amplifier selection: This machine uses OPA2134PA dual operational amplifier. Our circuit board is equipped with op amp sockets, customers can try to replace other dual op amps, but be careful not to plug in the opposite direction.

4. Gain selection: The factory default setting of the amp is 10dB gain. HD650/600 is recommended to be set to 10DB, which is subject to personal hearing. Reminder: It is best to turn off the power when setting the gain and turn off the volume to the minimum.

Applications