Description

XiangSheng 728A Vacuum Tube preamp Shigeru Wada circuit home preamplifier without button black Product introduction: This machine has been improved several times on the basis of the third generation 728 bile preamplifier. Compared with the original machine, the appearance is elegant and solemn, and the taste is extraordinary. In addition to retaining all of its advantages, it also adds the following advantages: 1. It is designed with circuit board, and the internal layout is more reasonable, neat and beautiful. The front panel is made of silver 6mm thick aluminum plated wire drawing process panel, blue power indicator tube, and a unique electronic tube display large window, the background is warm red orange, the grade is higher. 2, advanced sandblasting technology, thin steel box, high-gloss metal knob, honeycomb-type large machine feet. 3. Signal input 4 sets of stereo switching, using traditional rotary switch to control the advanced fully sealed relay to achieve signal conversion, avoiding switching noise and long life. The signal output adopts the relay delay. After the amplifier tube enters the stable working state, the relay picks up the output signal, avoiding the unpleasant noise generated by the electron tube during the warm-up process. 4, the output signal provides two sets of output, you can play the bi-amp system (the instructions marked on the high and low level, now the machine is no longer high or low, the two sets of output are the same. ) 5. The input and output interfaces are all made of gold-plated RCA lotus seat to reduce the contact resistance. 6, the power inlet line uses three plug sockets, easy to replace the upgrade power cord. 7. Designed with power grid filter purification circuit, it can filter out clutter interference and DC components in the power grid. 8. It uses antique oil-immersed capacitors and polypropylene capacitive coupling such as imported WIMA. 9, using the high-performance R cattle power supply in the transformer, the price is high (circle cattle and square cattle magnetic leakage, radiation noise, low efficiency, and R cattle efficiency of up to 90%, magnetic drain is small). 10, high voltage using tube rectification, 2 parallel, providing enough current. 11. Two large reservoir filter capacitors plus inductive filtering form a CLC filter circuit with good filtering effect, which suppresses residual noise. 12. The tube filament is powered by AC, which is warmer and more resistant than DC power supply, does not cause sound hardening, and prolongs the life of the tube. And to ensure that the interference of the filament is minimized. Specification: Size: 435 × 90 × 290mm Input impedance: 100K Output impedance: 600 ohms Signal to noise ratio: 90dB Frequency response: 20Hz--30KHz (+-1dB) Distortion: ≤ 0.01% The internal line tube of the machine: 12AT7×2, 12AU7×2, 6Z4×2 Net weight: about 5.6kg Gross weight: about 9kg Input Power Voltage: AC100V - AC240V(60Hz/50Hz)(100V, 110V, 120V, 127V, 230V, 240V version will take 3-14 work days to order. 220V version is in stock. About Us : We are dedicated to offer the best audio-visual products at the lowest price to our customers. Bringing great products and customer service, and thus help enriching our customers’ lives is our ultimate goal. About shipping : 1. The order will be shipped by Fedex, DHL, TNT or UPS come with a tracking number and take 3-14 business days to your door. Shipping to Russia takes longer time, it usually takes 10-25 business days via CDEK or other express with a tracking number. 2.We ship the package within 7 days after the payment cleared. 3.We ship to PayPal's address ONLY. Please make sure your phone number and your address in PayPal is matched with your shipping address before you pay. 4.We have no reasons to refund to the non-authenticated accounts. 5.Faster payment, faster delivery. 6. If you have not received your shipment within 30 days from payment, please contact us. We will track the shipment and get back to you as soon as possible with a reply. Our goal is customer satisfaction! About Return Policy: 1.if you find there are some items missing from your order or we sent you incorrect items or you find the item is damaged (cracked) in appearance or the item does not work , please keep all the items in original condition and also keep the packing stuff, weigh all the items together with packing, then take some photos of them and send us the photos by email. Please contact us within 7 days after receipt of package. We will investigate the case when we get your email. If the case is true, we will send you the missing item or replacement or refund (sometimes you may be requested to return the incorrect item). 2.ONE-YEAR WARRANTY !!! 3.Defective situation must be reported to seller within 10 days upon receipt. all items must be returned within 30days of purchasing the item 4.Returned packages displaying an invalid or expired will not be accepted. 5.Returned item should be in its original box with all packing materials and shipped to us via a traceable means. 6.We carefully inspect returned items upon receipt before issuance of refunds or exchanges. 7.Please allow up to 10 business days for us to process your return. 8.Shipping and handling charges, insurance are not refundable in any case. 9. The customer need to pay for shipping costs for exchanging or returning. Reply 1.ALL replies will be sent to your email, if you don't get response within 1-2 business days, pls check your My Messages in case your email provider has an overly-aggressive spam filterblocking eBay's emails. Please email us AGAIN. 2.Our office hours are 8:30 a.m to 6:00 p.m (GMT +8) of Monday to Friday. 3.And our Office is closed on Sunday and public holidays.We apologize for the late reply during the holidays. About feedback: 1.Since online shopping uncertainty, so thank u very much for choosing&trusting us.our service is ready to help u any time,your feedback is extremely important to us. 2.Any product or shipping issue, please contact us before opening the dispute or leaving any feedback, we'll carefull to do our endeavor to solve problems to the most make you satisfied. 3.In case of returns, please contact us first, you describe the problems and reasons. Then we'll send you the return slip. For all other questions contact us by site message or email.