Dongyang City Redsun Electro Acoustic Co., Ltd.
Main products:Mini Speaker,Loudspeaker,Car Speaker,Home Theater Speaker,Speaker
Contact Us
  • Contact Person : Mr. Lee Michael
  • Company Name : Dongyang City Redsun Electro Acoustic Co., Ltd.
  • Tel : 86-579-86312211
  • Fax : 86-579-86312299
  • Address : Zhejiang,Dongyang,Hengdian Industrial Area, Dongyang, Zhejiang,China
  • Country/Region : China
  • Zip : 322118

Rechargeable Portable Waist Hanged Voice Amplifier GP977 red

Rechargeable Portable Waist Hanged Voice Amplifier GP977 red
Product Detailed
1,with CE,ROHS,ISO etc 2,professional amplifier,with USB,TF,MPS input 3,several colors to selection:black,red   Specifications: Output Power: 25W  Frequency Response: 100HZ ~ 10,000 HZ + 1db Consumption Current: 150mA Voltage: DC 7.5, li-ion battery Battery Type: Lithium Battery Size: 125x55x100 mmWeight: 320g Color: red ,black

The amplifier speaker is engineered for enriched sound reproduction and has a highly steady operating distance. The amplifier speaker features extended frequency response range. Clear sound reproduction for live applications. This amplifier speaker is suitable for on-stage performance, teacher guide and so on.



1,with USB,TF,MP3 input

2,FM radio with antenna

3,with echo



The Rechargeable Voice Amplifier adopts ABS engineering plastic, impact resistance Tone clear Applicable area of 400 square meters This Portable Voice Amplifier gives you the freedom to move around your stage or classroom at your will with no leads or cords attaching you to one point Battery (lithium battery) use time long, can reach 15 hours ,Battery life  can reach 2-3 years Cooperate with wearing type microphone Amplification effect is good Easy to use, can make MP3 player

Audio Amplifier Technology:

Audio amplifiers feed electric power to speakers to reproduce music or other sounds at a wide range of volume and frequency levels, according to Audioholics A/V Magazine. These devices build up a "storehouse" of electrical power, then release that power in a way that precisely replicates the original sound wave pattern it receives from a playback device. The best amplifiers perform to exacting specifications, delivering as little sound distortion as possible to the speakers.


Amplifiers make use of an exterior alternating current, or AC power source, collecting the power from an ordinary wall outlet and storing it up in a set of capacitors. It also receives a second, weaker AC signal that contains the audio sound wave information from the music player. The weaker signal from the input stage "tells" the the output stage how much electricity to release from the amplifier's stores, recreating the sound waves in a more powerful form to drive audio speakers.


Amplifiers use either vacuum tubes or solid-state transistors to modulate their signals, according to Audioholics. While both technologies create a certain unavoidable amount of distortion as the amplifier adds more power to the audio signal, tube amplifiers tend to distort in a more harmonically agreeable way than solid-state amplifiers which tend to add a harsh, unmusical distortion known as "clipping."


Manufacturers construct different classes of amplifiers that offer different levels of power efficiency. Class A amplifiers send a constant flow of power through the output transistors, resulting in low distortion but high heat and just 20 percent efficiency. Class B amplifiers divide the waveform reproduction between two alternating output transistors that shut off completely when so signal reaches them, yielding up to 70 percent efficiency. Class A/B amplifiers allow the switching between transistors to overlap slightly, reducing potential distortion but reducing efficiency to 50 percent. Class D amplifiers, which use ultra-high frequencies to regulate switching operations, offer efficiencies of up to 90 percent.

Performance Measurements

The best amplifiers perform to precise frequency, distortion and power measurements. Audio enthusiasts look for the flatness of the amplifier's frequency response indicating that the device performs evenly throughout all the frequencies from 20 Hertz and 20,000 Hertz. They also prize a harmonic distortion level under 0.5 percent, the level in which any distortion the amplifier introduces becomes inaudible underneath the music. Power levels of at least 50 to 100 watts per channel enable the amplifier to handle a wide dynamic range without distortion.






With mini remote control




Package Included:

1 x Lithium Battery 1x  Remote control1 x Amplifier Speaker 1 x Microphone 1 x Belt 1 x Specification 1 x Power Adaptor

With ROHS,CE,ISO 9001 certificate

Rechargeable Portable Waist Hanged Voice Amplifier GP977 red

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