27 In stock
Single-ended tube amplifier
Vacuum Tube Amplifier 300B Kit Single-ended Class A No soldering 6F3 Preamplifier DIY Kits HIFI
Model No: WHFVT-WE6F300BKITS
Vacuum tube 300B is a mysterious vacuum tube with a long history, and don’t know how many music fans are fascinated. I still don’t know how many people are struggling to find its real voice. The audiophiles think that 300B is a female voice representative. But our 300B kit circuit is the embodiment of the sound of rigidity and softness. It is not only an attentive and charming woman, but also an iron and tender prince charming.
There are also rumors that the low frequency of 300B is not good. From an electrical point of view, the internal resistance of 300B is only about 800 ohms, which shows its damping coefficient is very good. Why is the rumors so? This is depended on the quality of the power supply, time constant of the circuit design and other reasons.
In fact, 300B tube is the best way to reflect the original atmosphere of music, because the tube’s characteristic curve distribution is excellent, coupled with second-harmonic sense of hearing, the mouth shape of the singer, the low-frequency tension of the chest resonance, its dynamics can be said to reach the perfect state, if regardless of the power, hundreds of thousands of transistor world-famous machines are difficult to surpass in the same power range as the 300B. From the acoustic point of view, the sound of the 300B tube amplifier is more expressive and richer, musical sense.
Our vacuum tube 300B kit has a unique acoustic and electrical regulatory concepts from the design to the selection of the output transformer.
The vacuum tube 6F3 is a relatively unpopular composite tube, which is quite a 12ax7+6p14 inside. Because of the large inventory, the price is related low, but its performance is extremely excellent, especially when it is connected as triode tube, which output internal resistance is particularly low, and linearity is good, driving 300B is absolutely no problem. In addition, many senior enthusiasts will inevitably ask, why use large loop feedback? This is our consideration of sound and stability. The large loop will sacrifice the transparency of mid and high frequencies. However, in order to improve the weakness of the low frequency of the tube, adopt the large loop can will make the internal resistance of the 300B tube amplifier lower, so that its overall sound balanced.
DIY by audiophiles
After assembling and soldering
1. 260W power supply cattle*1 (British Red Bull iron core 105*70)
2. 25W output cattle*2 (British antique iron core 86*40, impedance: 3.5K; output: 0-4-8 ohms)
3. Choke coil*1 (Japan Z11 iron core 76*50, 10H250ma)
4. 300B*2 (new original matched)
7. Potentiometer *1 (original alps27 type 50K)
8. Output terminal *6 (2 gold-plated high-current black, 4 red)
9. RCA input terminal *4 (Taiwan-made gold-plated, 2 red and white signal conversion switches *1)
10. Tube socket*6 (two large 4-pins, two 8-pins, two nine-pins with shielding)
11. Resistance package *1 (large current *4, low power is shown in the figure)
12. Capacitor package*1
13. VU meter*1
14. Welding board (4 sets, including screws)
15. Circuit diagram*1 (updated version)
16. Matching package *1 (1-meter high-quality signal line, 2 meters silver tinned wire from the United States)
17. Delay circuit finished board *1 piece
18. Chassis: chassis bottom, liner, upper chassis (size: 420*240*65mm)
1. Weight: 17KG (approximately 14.5kg without chassis)
2. Power: 8W x 2
3. Power consumption: 160W
1. This kit is only available to DIY enthusiasts who have circuit diagram recognition, hands-on skills, and problem-solving skills. Buyers who do not have the corresponding hands-on experience and problem-solving skills, please do not buy.
(If necessary, the finished tube amplifier can be purchased directly as the link below.)
2. We only provide the kit and do not provide any technical support;
3.If you purchase it, it means you accept the terms above.
Circuit diagram for you information only
1.Important: Import duties, taxes and other customs related charges all are not included into shipping cost . Buyers bear all responsibility for all extra charges incurred (if any).
2. We only ship to confirmed order addresses. Your order address MUST MATCH your Shipping address. We can ship to virtually any address in the world. Note that there are restrictions on some products, and some products cannot be shipped to international destinations.
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4.Please also note that the shipping rates for many items we sell are weight-based. The weight of any such item can be found on its detail page. To reflect the policies of the shipping companies we use, all weights will be rounded up to the next full pound. The shipping rate can be showed at the Checkout page. There are two options for shippig as below.
A. Standard Shipping(≤2KG): The Post Registered Air Mail, USPS/ePacket, PostNL, Singapore Post, or DHL Global Mail
B. Express Shipping: EMS, DHL, UPS , or Fedex, Special Route.,etc. For faster shipping and smooth transaction, we will change the shipping company among themC. Economy Shipping: China Air Post Mail / Parcel, Hongkong Air Post Mail / Parcel, or shipment by sea etc
You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
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1. One year Manufacturer`s limited Warranty for defective items (excluding items damaged and/or misused after receipt). Accessories come with a 3-month warranty.2. Defective items MUST BE reported and returned within the warranty period (with the original packaging, if possible). You must tell us what the defect is and give us your order number. WE DO NOT REPAIR OR REPLACE ITEMS WITH AN EXPIRED WARRANTY. You agree to all of the above-listed policies upon ordering on our store.