1pair L25 pre and post combined amplifier bi-channel 250W 8R
Parameter：
Low distortion, high drive, high power integrated amplifier designed by LJM
Dual-channel, two boards in total.
Each channel uses four pairs of original imported KEC KTB817 KTD1047 transistors
Using Sanken LAPT type audio tube 2SA1186 2SC2837 as the driver tube.
Pre-stage using the original JRC4580 D ultra-low noise, ultra-low distortion op amp.
No coupling full DC amplification.
Using thickened 2.0MM PCB
Little knowledge popularization:
The power of the current network amplifier false labeling is common. Many only 50 watts of power dare to claim 500W is often seen.
How to judge the output power of the amplifier?
In fact, the maximum output power refers to the amplifier can be the maximum output voltage range. In general, the current output can be reached.
According to the power supply voltage of the amplifier. Half-bridge amplifier to ground, the output voltage does not exceed the supply voltage.
In other words, look at the maximum supply voltage of the amplifier can calculate the power of the amplifier.
In the same load impedance is generally regular to 8 ohms of load as a reference.
The power of the amplifier and voltage calculation of the basic parameters are:
DC power supply, + -35V voltage output power 50 watts 8R.
+ -40V voltage, output power 80W 8R.
+ -50V voltage, output power 125W 8R.
+ -63V voltage,output power 200W 8R.
+ -70V, output power 250W 8R.
+ -80V voltage. Output power 300W8R.
L25 combined amplifier parameters:
Output power 250W 8R ,500W 4R + -70V supply.
200W 8R ,400W 4R + -63V supply.
125W 8R, 250W 4R + -50V supply.
250W 4R,500W 2R + -50V supply
Maximum output current 20A, maximum output voltage sine wave + -67V.(+ -70V supply)
Static current 20MA per channel
Static power consumption = supply voltage * 0.02(2W+ -50V)
Power Supply Voltage Range: + - 24V to + - 70V
Recommended supply voltage and heat sink standard :
+ -35 to + -50V, heat sink 0.5KG per channel
+ -40 to + -60V, radiator 1KG per channel
+-60V to +-70V, radiator 2KG per channel.
If you use + -60V or more voltage. As the heat generation is relatively large, it is recommended to apply silicone grease on the back of the angle aluminum.
With a large heat sink for good thermal conductivity.
Pre-stage gain 4.7 times. Rear stage gain 25 times. Total gain 117 times.
Frequency response range 5 HZ-300 K HZ-3DB. 20HZ-20K HZ + -0.2DB.
Distortion 100W 1K HZ THD < 0.01%
Damping factor > 3000 ,8 Ohm load.
S/N ratio > 97DB.
Input sensitivity:0.6V RMS 250W 8R power
Size: length 130MM. width 95MM including angle aluminum.
Package：
1pair L25 preamp post-amplifier dual channel 250W 8R
Parameter：
Low distortion, high drive, high power integrated amplifier designed by LJM
Dual-channel, two boards in total.
Each channel uses four pairs of original imported KEC KTB817 KTD1047 transistors
Using Sanken LAPT type audio tube 2SA1186 2SC2837 as the driver tube.
Pre-stage using the original JRC4580 D ultra-low noise, ultra-low distortion op amp.
No coupling full DC amplification.
Using thickened 2.0MM PCB
Little knowledge popularization:
The power of the current network amplifier false labeling is common. Many only 50 watts of power dare to claim 500W is often seen.
How to judge the output power of the amplifier?
In fact, the maximum output power refers to the amplifier can be the maximum output voltage range. In general, the current output can be reached.
According to the power supply voltage of the amplifier. Half-bridge amplifier to ground, the output voltage does not exceed the supply voltage.
In other words, look at the maximum supply voltage of the amplifier can calculate the power of the amplifier.
In the same load impedance is generally regular to 8 ohms of load as a reference.
The power of the amplifier and voltage calculation of the basic parameters are:
DC power supply, + -35V voltage output power 50 watts 8R.
+ -40V voltage, output power 80W 8R.
+ -50V voltage, output power 125W 8R.
+ -63V voltage,output power 200W 8R.
+ -70V, output power 250W 8R.
+ -80V voltage. Output power 300W8R.
L25 combined amplifier parameters:
Output power 250W 8R ,500W 4R + -70V supply.
200W 8R ,400W 4R + -63V supply.
125W 8R, 250W 4R + -50V supply.
250W 4R,500W 2R + -50V supply
Maximum output current 20A, maximum output voltage sine wave + -67V.(+ -70V supply)
Static current 20MA per channel
Static power consumption = supply voltage * 0.02(2W+ -50V)
Power Supply Voltage Range: + - 24V to + - 70V
Recommended supply voltage and heat sink standard :
+ -35 to + -50V, heat sink 0.5KG per channel
+ -40 to + -60V, radiator 1KG per channel
+-60V to +-70V, radiator 2KG per channel.
If you use + -60V or more voltage. As the heat generation is relatively large, it is recommended to apply silicone grease on the back of the angle aluminum.
With a large heat sink for good thermal conductivity.
Pre-stage gain 4.7 times. Rear stage gain 25 times. Total gain 117 times.
Frequency response range 5 HZ-300 K HZ-3DB. 20HZ-20K HZ + -0.2DB.
Distortion 100W 1K HZ THD < 0.01%
Damping factor > 3000 ,8 Ohm load.
S/N ratio > 97DB.
Input sensitivity:0.6V RMS 250W 8R power
Size: length 130MM. width 95MM including angle aluminum.
Package：
1pair L25 preamp post-amplifier dual channel 250W 8R
