Tube Amplifier 2 X 16W FU17 Mini Push-pull with Switching Power

Traditionally,a tube amplifier is fixed a large and big power transformer to output high voltage like as AC 300V or more, or 6.3V for filament of vacuum tube,then it will be heavier due its multi-outputs. Have you thought to reduce the weight but effect sound quality? Now, we developed a tube amplifier with switching power supply, it can realize the purposes.

Here,it is a tube amplifier with switching power supply, which adopted aluminum chassis designing, compact and simple, suitable for desktop hi-fi and home theater users. Used tube 6F2 as preamplifier, tube FU17 as power stage with push-pull circuit output that work with Class A and B, both sweet tube amp sounds, and bigger dynamic, stronger resolving power. 

Its output power is up to 2 X 16W. At the same time, it is built in DAC decoder, convenient external connection with a laptop, smart phone that must support OTG function.

We suggest that please use high quality signal audio cable to connect the amplifier, or play hifi audio sourcing like as CD, lossless signals (APE, FLCA, WVA) when the unit connect with signal sourcing via line-in, the you will get high quality performance from the unit.

Tube Amplifier Mini Push-pull with Switching Power Moddel WVTDSA-FU17

Wooden Panel--Tube Amplifier Mini Push-pull with Switching Power Model WVTDSA-FU17

With DAC input -- Tube Amplifier Mini Push-pull with Switching Power Model WVTDSA-FU17

Specifications

1. Output Power: 2 X 16W 

2. Signal Input: Line-in, USB (USB input priority)

3. USB part: DAC, support 16bit 48 KHz decoding

4. Frequency response: 20Hz-20 KHz (+ 0.5dB / -1dB)

5. Output Impedance: 4/8 ohms

6. Total harmonic distortion: 0.3% (1 kHz,5W)

7. Input Sensitivity: 0.3VRMS

8. Input impedance: 10K

9. SNR: 92dB

10. Tubes: 6F2 × 2 FU17 × 2

11. Operating voltage: 110 ~ 240V / 50 ~ 60HZ

12. Dimension (W * D * H): 125mm × 185mm × 120mm

13. Net Weight: 2.7Kg

14. Gross Weight: 3.5KG

15. Accessories:

Power cord x 1

3.5mm to 2 RCA audio cable x 1

support OTG function--Tube Amplifier Mini Push-pull with Switching Power ModdelWVTDSA-FU17

Application--Tube Amplifier Mini Push-pull with Switching Power Model WVTDSA-FU17

Application as desktop audio --Tube Amplifier Mini Push-pull with Switching Power Model WVTDSA-FU17

More details, please find http://www.aliexpress.com/store/product/HIFI-Tube-Amplifier-Mini-Push-pull-with-Switching-Power-Supply-2X16W-6F2-Preamplifier-FU17-Power-Stage/725205_32338488920.html

A HIFI Transistors Power Amplifier with Mellow and Soft Sound Tube Taste 2 x 80W

A HIFI Transistors Power Amplifier with  Mellow and Soft Sound Tube Taste 2 X 80W

Power Amplifier of Named Naim is one of those products worshiped by audiophiles like as Linn turntables. Though its unassuming appearance, but it has won the hearts by warm mellow tone. Naim price is not low, people who really know what was the expert are willing to spend money to buy it. If you are truly listening to music, you will feel that once you owned and not much else for this amplifier.

I love this circuit Naim NAP140 as much love for the 1969 circuit. Because it sounds isn’t worse than 1969, and its output power is far better than 1969. One feature of NAP140 amplifier architecture is its mostly second-harmonic distortion, so the tone is somewhat like as tube amplifier charm. But the difference is that it is very rewarding that the distortion of tube amp to achieve 0.1%, but this circuit can be achieved 0.01% distortion.

 HIFI Transistors Power Amplifier with Mellow and Soft Sound Tube Taste 2 x 80W

HIFI Transistors Power Amplifier with Mellow and Soft Sound Tube Taste 2 x 80W

Inside view -- HIFI Transistors Power Amplifier with Mellow and Soft Sound Tube Taste 2 x 80W

PCBA--HIFI Transistors Power Amplifier with Mellow and Soft Sound Tube Taste 2 x 80W

We made this HIFI amplifier to refer to Naim Nap140 designing, and hope in keeping NAP140 original fine circuit architecture as same premise, to use new devices, greatly improve the operating voltage and output power, improve stability, and to Try to do something to improve the circuit (for example, the circuit adapted to work class A state). The original unit is very popular with enthusiasts respected, but also the price of its second-hand is nearly USD 2000. We do not engrave it, and cannot do it, only with reference to its excellent circuit configuration. The amplifier’s circuit is very mature, stable, ultra-low power consumption, driving and control force is very, very good, far better than integrated circuit amplifier or similar circuit at same output power, it is cannot be compared by them. More commendable is that the sound of this Class B circuit is mellow and soft as same as class A one at low power consumption.

Its output power is able to reach 80W at 8 ohms and class B state.

Sch.-- HIFI Transistors Power Amplifier with Mellow and Soft Sound Tube Taste 2 x 80W

Features

1. Basically to be faithful to H140 classic circuit.
2. Add upc1237 speaker protection system, switch absolutely no impact sound while performing midpoint of DC protection, to prevent damaging or burn your expensive speakers due to the amplifier circuit.
3. Integrate volume control potentiometer.
4. Integrate a two inputs switch on the front panel, you can switch the input source via the front panel.
5. Add a midpoint adjustment circuit on differential input, generally midpoint can adjust to 5mV or less.
6. The finished unit with about 2KG heat sink, while it is whole aluminum design, this benefit other parts of the casing become heat sink also in addition, so that the total heat dissipation area greatly increased. Its actual operating temperature up to 40 degrees, low-carbon green!
7. Use a special custom 200W HIFI OFC toroidal transformer, ensure enough reserve power!
8. Use a lot of HIFI elements like as ALPS27 potentiometers, high-grade RCA connect, ELNA capacitors and HIFI chemicals one. Sound’s quality is the most important thing.

Specifications

1. Maximum output power: 80W * 2 (at 1KHz sine wave equivalent without distortion).
2. Frequency response: 20Hz-20KHz
3. Input sensitivity: <2Vrms.
4. Distortion: <0.01% (at 1 kHz)
5. SNR:> 100dB
6. Amplification voltage gain: 28 times.
7. Output impedance: 4 - 16Ohm
8. Supply voltage: AC220V / 50Hz
9. Average power consumption: <150W
10. Dimensions (W * H * D): 215mm * 70mm * 228mm
11. Weight: 4.8Kg
12. Accessories:

Power cord X 1

More details, please find http://www.aliexpress.com/store/product/HIFI-Power-Amplifier-80Wx2-Stereo-Refer-to-Naim-NAP140-Mellow-Soft-Sound-Tube-Taste-Black-Whole/725205_32522391541.html

Personalized Ultra-Class A (Class AA) Headphone Amplifier with Portable Design

Personalized Ultra-Class A (Class AA) Headphone Amplifier with Portable Design

Audiophiles had asked me, or whether the device or circuit determines the sound quality? In our experience, the answer is, circuit design, technology and debugging is more to decide sound, HIFI devices, op amp selection and personalized tone tuning is more to define Timbre. It is so-called HIFI to focus on quality, high-fidelity idea. The HI-END is integrated personalized tuning philosophy into the trend to the highest HIFI level.

There is a portable headphone amplifier that is designed according to the concepts as above. 

Portable Ultra-Class A (Class AA) Headphone Amplifier--Gray

Portable Ultra-Class A (Class AA) Headphone Amplifier -- Black

Personalized design, all aluminum casing, ultra-thin body. Circuit structure used a ultra-Class A (Class AA) circuit, because voltage amplifier stage of Class AA headphone amplifier is equivalent to a no-load state, no matter how the load followed by the headphone, it will not affect the voltage amplifier stage of work, which is common Amplifiers can not achieve that status. As results, it will make a very real interpretation of the music, space and very good positioning performance, and efforts to extend the sense of sound performance; it is just a little weird. In addition, we use HIFI grade components and process to make it, and bring a better listening experience.

It's PCBA inside

Selection aspect of the op amp, we used OP IC OPA2604 plus LM4562 match, we passed several tests comparing those match, we find that they can complement each other; If the preamp use OPA2604, and power stage use LM4562, we tested them with a 20KHz square wave, which output waveform distortion is very small. From the listening sensation, LM4562 relatively straightforward, OPA2604 more beautiful!

OP Amplifier used

Specifications

1.       Output power: 320mW (at 32 ohm)

2.        Headphone Impedance: 16 ~ 300 ohms

3.       Total Harmonic distortion: <0.0005%

4.       Frequency Response: 20Hz ~ 20Hz

5.       SNR :> 110dB

6.       Built-in rechargeable lithium battery 1200mAH

7.       Weight: 0.5kg

8.       Dimension (L * W * H): 100 mm * 61mm * 13mm

9.       Color: Black / Silver/Gray

10.       Accessories

    3.5mm audio cable x 1

    USB charging cable x 1

3 color selections

Appliccations by audiophiles

More detail, please find http://www.aliexpress.com/item/HIFI-Headphone-Amplifier-Portable-Ultra-Class-A-Class-AA-OPA2604-plus-LM4562-320Mw-16-300ohms-Li/32400230250.html

Bluetooth study tool---CSR8645 Rom Version Development Simulation Demo Board

Bluetooth study tool---CSR8645 Rom Version Development Simulation Demo Board (For study only)

Have you thought to develope yourself Bluetooth speaker? Maybe it is a crazy thinking, but if you have some basic Bluetooth program and hardware skills and love to DIY your things, or study this porpular and fantactic things, you can try it.Also, if you can solve that you will face problems of Bluetooth speaker development, you can try it from this CSR8645 Rom Version Development Simulation Demo Board.

Here is the board. It is fast, convenient, practical and essential tool for product developmentwith 4M FLASH for product developers . This board can be used to develop a Bluetooth headset, car handsfree, Bluetooth speakers, etc.

CSR8645 Rom Version Development Simulation Demo Board

Main features as below

1.     Provide 3W amplifier output can be directly connected to the speaker as a Bluetooth speaker using.

2.     Offers 3.5 headphone output interface, plug in headphones can be used directly as a Bluetooth headset.

3.     Provide 3.5AUX-IN port, support AUX-IN switching.

4.     MIC interface, can make and receive calls, and provides debugging Dual MIC noise cancellation.

5.     SPI debugging burning interface for easy developer debugging.

6.     Bluetooth PIN feet IO ports are reserved for development and debugging use.

7.     Buttons, eight IO ports with LED indication IO port operation.

8.     MFB provide power button and the power button to boot the boot in two ways.

9.     Three-color LED indication, LED status debugging easier.

10.  Using 4M FLASH, large space, easier debugging voice prompts.

11.  USB communication capabilities for debugging USB sound card functions.

12.  This development board backplane can be used for all other modules CSR.

There are related software to be download for your study. 

More details, please find http://www.aliexpress.com/store/product/CSR8645-Rom-Version-Development-Simulation-Demo-Board-4M-Flash-Free-Shipping/725205_1827253316.html

Speaker driver’s construction and related function

Speaker driver’s construction and related function

In any sound system, ultimate quality depends on the speakers. The best recording, encoded on the most advanced storage device and played by a HIFI speaker and amplifier, will sound awful if the system is connected with poor speakers.

A system's speaker is the component that takes the electronic signal stored on things like CDs, DVDs or digtial media such as your smartphone, tablet, music players, and turns it back into actual sound that we can hear.

A speaker is essentially the final translation machine -- the reverse of the microphone. It takes the electrical signal and translates it back into physical vibrations to create sound waves. When everything is working as it should, the speaker produces nearly the same vibrations that the microphone originally recorded and encoded on a tape, CD, LP, etc.

4 inches full range speaker driver unit

Side view

Now, let us take a look those components or parts of speaker. A typical speaker driver includ a metal basket, diaphragm (or cone), voice coil, spider, permanent magnet, ans also include dust cap, terminal,top plate, pole piece.

•     The cone, usually made of paper, plastic or metal, is attached on the wide end to the suspension.
•     The suspension, or surround, is a rim of flexible material that allows the cone to move, and is attached to the driver's metal frame, called the basket.
•     The narrow end of the cone is connected to the voice coil.
•     The coil is attached to the basket by the spider, a ring of flexible material. The spider holds the coil in position, but allows it to move freely back and forth.
•     The dust cap covers the voice coil opening and sperker internal.
•     The terminal with positive and negative is soldered wires where electronic signal come from.
•     The top plate and pole piece to fix permanent magnet

 

Speaker driver's construction, the photo come from network, only for demostration there.Thank you for the original author

There are key parts for making sound

Diaphragm

A driver produces sound waves by rapidly vibrating a flexible cone, or diaphragm. Some drivers have a dome instead of a cone. A dome is just a diaphragm that extends out instead of tapering in.

Voice Coil

When the electrical current flowing through the voice coil changes direction, the coil's polar orientation reverses.The voice coil is a basic electromagnet. An electromagnet is a coil of wire, usually wrapped around a piece of magnetic metal, such as iron. Running electrical current through the wire creates a magnetic field around the coil, magnetizing the metal it is wrapped around. The field acts just like the magnetic field around a permanent magnet: It has a polar orientation -- a "north" end and and a "south" end -- and it is attracted to iron objects. But unlike a permanent magnet, in an electromagnet you can alter the orientation of the poles. If you reverse the flow of the current, the north and south ends of the electromagnet switch.

This is exactly what a stereo signal does -- it constantly reverses the flow of electricity. If you've ever hooked up a stereo system, then you know that there are two output wires for each speaker -- typically a black one and a red one.

Essentially, the amplifier is constantly switching the electrical signal, fluctuating between a positive charge and a negative charge on the red wire. Since electrons always flow in the same direction between positively charged particles and negatively charged particles, the current going through the speaker moves one way and then reverses and flows the other way. This alternating current causes the polar orientation of the electromagnet to reverse itself many times a second.

Magnets

When the electrical current flowing through the voice coil changes direction, the coil's polar orientation reverses. This changes the magnetic forces between the voice coil and the permanent magnet, moving the coil and attached diaphragm or cone back and forth.

So how does the fluctuation make the speaker coil move back and forth? The electromagnet is positioned in a constant magnetic field created by a permanent magnet. These two magnets -- the electromagnet and the permanent magnet -- interact with each other as any two magnets do. The positive end of the electromagnet is attracted to the negative pole of the permanent magnetic field, and the negative pole of the electromagnet is repelled by the permanent magnet's negative pole. When the electromagnet's polar orientation switches, so does the direction of repulsion and attraction. In this way, the alternating current constantly reverses the magnetic forces between the voice coil and the permanent magnet. This pushes the coil back and forth rapidly, like a piston.

When the coil moves, it pushes and pulls on the speaker cone. This vibrates the air in front of the speaker, creating sound waves. The electrical audio signal can also be interpreted as a wave. The frequency and amplitude of this wave, which represents the original sound wave, dictates the rate and distance that the voice coil moves. This, in turn, determines the frequency and amplitude of the sound waves produced by the diaphragm.

Different driver sizes are better suited for certain frequency ranges. For this reason, loudspeaker units typically divide a wide frequency range among multiple drivers.

There are more HIFI speaker driver units that cover most of the kinds on the market. More details, please find 

http://www.aliexpress.com/store/group/HIFI-Speaker-Unit/725205_256208811.html

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