Basic Info.
Type
Professional Amplifier
Product Description
The 728A has mature design, One of the hot recommended products, mature design, outstanding sound quality, stable performance, good reputation, hot sales at home and abroad. The machine can be connected to a pure post-stage power amplifier; It can also be connected to the machine as a timbre adjuster and further improve the sound quality. The actual sound quality of a set of audio system is important related to the sound source, the front and rear stages of the power amplifier, and the quality of the speaker, if the other parts of the system are balanced and reasonable, the sound quality of this machine will not disappoint.
It adopts 4 antique oil-immersed capacitors coupling, and mixes with German WIMA and ERO capacitors, Siemens capacitors and other polypropylene capacitors with good resolution, so that the sound is warm and delicate without losing resolution. The internal signal line adopts imported silver-plated wire, which is very helpful for improving signal details, reducing signal loss, and reducing induction noise. The machine also adjusts the line parameters for modern high-level sound sources to ensure that large signals can be easily passed without clipping.
Product feature
This machine has been improved many times on the basis of the third generation 728 bold front stage, compared with the original machine, the appearance is elegant and solemn, and the taste is extraordinary. In addition to retaining all its advantages, the following advantages are added:
1. It is designed by circuit board, and the internal layout is more reasonable, neat and beautiful.
The front panel adopts silver 6mm thick aluminum alloy electroplated brushed process panel, blue power indicator tube, and adds a unique tube display large window, and the background is a warm reddish-orange color, which is higher grade (see figure below).
2. Advanced sandblasting paint process thin steel plate box, high-gloss metal knob, honeycomb type large foot.
3. Signal input 4 groups of stereo switching, using traditional rotary switch to control advanced fully sealed relay to achieve signal conversion, avoiding switching noise and long life.
The signal output adopts a relay delay, and the relay absorbs the output signal after the amplifier tube enters a stable working state, avoiding the unpleasant noise generated by the tube during the warm-up process.
4. The output signal provides two sets of outputs, which can play the bi-amp system (the manual is marked with high level high and low low, now the machine is not divided into high and low, 2 groups of output are the same. The actual machine shall prevail)
5. Gold-plated RCA lotus seat is used for input and input interfaces to reduce contact resistance.
6. The power supply line adopts a three-plug socket, which is convenient for replacing and upgrading the power cord.
7. Designed with power grid filter purification circuit, which can filter out clutter interference and DC components in the power grid.
8. Antique oil-immersed capacitors and imported WIMA and other polypropylene capacitors are adopted.
9. The use of high-performance R cattle power supply in transformers, the price is high (ring cattle and square cattle have large magnetic leakage, large radiation noise, low efficiency, while R cattle efficiency is as high as 90%, magnetic leakage is extremely small).
10. The high voltage adopts tube rectification, and the two are connected in parallel, providing sufficient current.
11. Two large pond filter capacitors plus inductor filtering constitute a CLC filter circuit with good filtering effect and suppress residual noise.
12. The tube filament adopts AC power supply, which is warmer and more durable than DC power supply, which will not cause sound hardening and prolong the life of the tube. And to ensure that the interference of the filament is minimized
Parameter
Input impedance | 100K |
Output impedance | 600 ohms |
Signal-to-noise ratio | 90dB |
Frequency response | 20Hz--30KHz (plus or minus 1dB) |
Distortion | 0.01%. |
Internal line pipes of this machine | 12AT7×2, 12AU7×2, 6Z4×2 |
Size | 435×90×290mm |
Ancillary equipment
The machine can be connected to a pure post-stage power amplifier; It can also be connected to the machine as a timbre adjuster and further improve the sound quality. The actual sound quality of a set of audio system is important related to the sound source, the front and rear stages of the amplifier, and the quality of the speaker, if the other parts of the system are balanced and reasonable, the sound quality of this machine will not disappoint.
Address:
High Tech, Hefei, Anhui, China
Business Type:
Manufacturer/Factory
Business Range:
Consumer Electronics
Company Introduction:
IIIWAVES audio is a company specialized in HiFi products relying on factories. The company′s products mainly include dac, pre amplifiers, integrated amplifiers, Power amplifiers and HiFi Accessories. We provide all kinds of HiFi products for the majority of enthusiasts to enjoy the hearing feast.