L1969  Battery version portable pure A headphone amplifier

Basic parameters:

• Line input: 3.5 stereo jack 1-2Vrms.
• Headphone output: 3.5 stereo headphone jack
• Output: 3.5 earphone dual-port output, earphones less than 32 ohm（150mW）; 100 ohm（60mW）.
• Voltage gain: 5 times
• Standard charger: 8.4V 500mA, optional upgrade 1000mA chargerhttp://item.taobao.com/item.htm?spm=0.0.0.0.cROTdX&id=40413825785
• Life time: about 7-8 hours.
• Charging time: 3-4 hours（500mA charger）, About 2 hours（1000mA charger）
• Volume: Volume: 100*62*27mm
• Weight: about 100 grams

L1969Battery Edition Portable Pure A Headphone Amplifier It is a high-fidelity headphone amplifier based on the improvement of the classic 1969 circuit; a circuit that has been popular for more than half a century and is still being talked about by enthusiasts, showing its skill. As a headphone amplifier, 1969 retains the sweet sound characteristics of the power amplifier. It also drives high-sensitive units such as headphones. The power output is very abundant. Under the low-voltage battery-powered condition, it completely surpasses the headphone amplifier with integrated chip and OP+Buffer structure.

1. Ultra-high signal-to-noise ratio, one of the benefits of battery power, without any noise floor!
2. Pure A circuit has a good current drive capability, and its quiescent current is designed to be 90mA, which is one of the signs of pure Class A. The quiescent current must be greater than the output current, so that the output tube does not enter the cut-off state, thereby eliminating unpleasant odds Distorted switching.
3. The output power is large. As a portable headphone amplifier, the first function is an amplifier. The output power of this board is 32 ohms to 150mW, and 100 ohm headphones can also have 60mW power output. The ER4S in the hands of the owner（Little Four）It can also be pushed well. As for most small earplugs, let me tell you, it''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''s a piece of cake. This is the theoretically based output power. It is the undistorted power in the pure A state. One of the advantages of the pure A machine is that its distortion does not change at the maximum power. Therefore, the pure A machine does not sound annoying if it is not turned on loudly.
4. The damping characteristic is good, this is also commonly referred to as the control force, and it is also one of the benefits brought by the pure A circuit. The auditory reflection is clean and neat.
5. Abundant even harmonics, when it comes to this, there is always a burning understanding that is suitable for listening to saliva songs, I tell you, it is wrong. The recordings with the most even harmonics are piano, violin, cello, etc. Even harmonics will make the hearing sense of air super strong, and the overtones are very rich. This is the benefit of the real pure A circuit. Except for the 1969 circuit, the stone machine has this kind of tube-like sense of hearing. I really don’t have it. Found it.
6. Fever materials, just look at this for yourself, a large number of Panasonic FM master capacitors, imported tubes from ON Semiconductor and Fairchild, imported A50K fever potentiometers, and gold-plated headphone sockets. To be honest, I am the least willing to say this, good-sounding is the first If it’s a bit, the stockpile must be finished. In fact, the most important thing is the tube pairing of the kit I shipped. In the 1969 circuit, the voltage amplifier tube and the push tube are paired with the left and right channels; the current expansion tube is matched with 1% of the working point.
7. 1969 is a capacitor output amp, which will never harm the earphones. It has a safer circuit structure than any protection circuit. Fans can use it with confidence.
8. The ultra-large-capacity lithium battery of 1200mAH guarantees the battery life of this machine to a certain extent. There are many portable amps on the Internet, with a capacity of several hundred mAh, and the claimed output power is several hundred milliwatts. It can also last for dozens of hours. I can only laugh, friends, we don’t understand circuits, we must know the law of conservation of energy!
9. Exquisite workmanship, CNC machined all-aluminum chassis, brushed oxidation, laser font.

Introduction to use:

1. The two 3.5 jacks on the front panel of the machine are line input and headphone output respectively. Do not connect them in reverse.
2. Behind is the power switch and the charging port. This unit can be rushed and listened to, but it will extend the charging time. If you often charge and listen to songs, it is recommended to upgrade to a 1000mA charger  http://item.taobao.com/item.htm?spm=0.0.0.0.cROTdX&id=40413825785, Add to the shopping cart together, contact the owner to subtract the difference of 8 yuan.
3. 1969 is a pure A circuit. It takes a certain period of time to start up, and it will not make a good sound after 2-3 minutes. Be sure to note that the state is better after half an hour. Most of it is flickering, but this is not!
4. Because this machine is a portable design, the owner has worked hard on sound tuning and static power consumption, so there is basically no big heat, probably less than 40 degrees at most.

Regarding the sound quality, this machine is definitely a warm color amp, the sound is warm and sweet, but I need to point out that the warm sound does not mean that there is no analysis. A good mid-frequency and no two-head frequency are two completely different concepts. I will not design a so-called so-called The vocal amp, and then there is no resolution, no dynamics, no high and low frequencies, it is a serious sound tuning.

After-sales terms:

• This machine has a free warranty of 1 year, and the battery warranty for half a year exceeds the warranty period, and maintenance charges will be charged for components.
• Please do not disassemble the machine without the buyer''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''s consent before confirmation, otherwise the seller has the right to refuse the return.
• Provide battery replacement service for life, charge a cost of 50 yuan, and the buyer will bear the freight.

Whether the appearance is tall or not, see for yourself!

How about the mold, there are details!

188 yuan, standard 500mA charger

Integrated design, this is design, well, I admit it is DIY, but is it worse than the factory machine? Looking at SOLO, I can''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''t help but smile.

The materials for fever are what every Taobao Hifi seller is willing to advertise, but I disdain it the most, because this is just a premise!