DjLeco
Moderator
I worked alot to build this one (just 10 modules made), is all in one amplifier ClassAB+B, (initially it was one ClassH prototype but I quit on that and keep AB+B class).
Each module contains balanced to unbalanced stage, IOC limiter (input output comparator limiter), thermal protection, overload and shorted output protection, auto fan based on heatsink temperature DC out protection (triac crowbarr), missing supply rail protection.
This amp is stable 2 ohms, and output current capability is around 50Amps RMS, limited by overload at 39Amps RMS.
Is based on Leco SMPS, custom version for 5,5Kwatts.
I have measured on dummy load as seen in videos (all are in Romanian language but is easy to see and understand what I have done there).
Bottom side
http://s13.postimg.org/6sjsj7qbb/Leco_V3_Bottom.jpg
Top side
http://s13.postimg.org/5g23hbsvr/Leco_V3_Top.jpg
Output stage
http://postimg.org/image/3rmd7y1hr/
Some components mounted
http://postimg.org/image/vhy5nrlsf/
http://postimg.org/image/wy9o5wopb/
http://postimg.org/image/nf4kq6qkv/
On all following tests, the cooling was very poor, one small fan just move the air!
Output current capability on 1 ohm dummy load:
https://www.youtube.com/watch?v=7N9bGpcKHrs
Thermal limiting and main supply current draw from soket wall at 1 ohm load:
https://www.youtube.com/watch?v=vXiCzzpsfnk
Output current capability on 2 ohms and thermal limiting:
https://www.youtube.com/watch?v=7CGDSu9w_IE
Some scope captures:
Sinusoidal 10kHz:
http://postimg.org/image/jjur4dma7/
Triangular 10kHz:
http://postimg.org/image/6jj07xzpr/
Rise-Fall Times on 8 ohms dummy:
http://postimg.org/image/3o5x12vpr/
8 ohms+1uF capacitive load on 10kHz squarewave:
http://postimg.org/image/6m2vus3db/
8 ohms+1uF capacitive load on 10kHz squarewave detail:
http://postimg.org/image/f32e5p827/
Maximum out voltage before clipping 8 Ohm on 10kHz sinusoidal:
http://postimg.org/image/qhyvabken/
Maximum out voltage before clipping 8 Ohm on 10kHz squarewave:
http://postimg.org/image/xmgojcrnz/
Max level then shorted output:
http://postimg.org/image/60dwyo8b3/
And now movies of above scope captures:
Leco V3 rise and fall times +capacitive load:
https://www.youtube.com/watch?v=b3aRnI0nfO4&feature=youtu.be
Leco V3 maximum output on sinusiodal and squarewave signal:
https://www.youtube.com/watch?v=BWNUFg5dgnQ&feature=youtu.be
Leco V3 reactive load 1000Hz 8 Ohm+143uH:
https://www.youtube.com/watch?v=Y4xE_w7JCWE&feature=youtu.be
Leco V3 shorted output and overload: (nice movie!!!)
https://www.youtube.com/watch?v=LH6TSYm7QTI&feature=youtu.be
During tests it was one scope probe uncalibrated, so now is OK
1000Hz probes compensation:
http://postimg.org/image/5ndskds7j/
10000Hz probes compensation:
http://postimg.org/image/wu5ac1pn3/
212Vpp between 10% and 90% in squarewave at 10kHz on 8 ohm load, 3,6uSec rise time:
http://postimg.org/image/jei9mlh5b/
Max out in squarewave at 10kHz capacitive load 1uF on output:
http://postimg.org/image/49qr2tibz/
Clean output at 100Hz on 8 ohm dummy load on output, almost 860 watts (yeloow is output signal, blue is input signal):
http://postimg.org/image/tpumf98un/
Clean output at 100Hz on 2 ohm dummy load on output, almost 2300 watts (yeloow is output signal, blue is input signal):
http://postimg.org/image/d61j6r8y7/
And movies of above scope captures:
1000 and 10000Hz probes compensation:
https://www.youtube.com/watch?v=45bljGxShas&feature=youtu.be
Leco V3 Amplifier Slew Rate Test+1uF Capacitor:
https://www.youtube.com/watch?v=_XRtqYWGOuI&feature=youtu.be
Leco V3 At Output 83-84Vrms/8Ohm Load:
https://www.youtube.com/watch?v=sRbl-yiexkY&feature=youtu.be
Leco V3 At Output 77-78Vrms/4Ohm Load:
https://www.youtube.com/watch?v=vOWOysoFKD0&feature=youtu.be
Leco V3 At Output 67-68Vrms/2 Ohm @ 224Vac
https://www.youtube.com/watch?v=I_Q4Lr38iXk&feature=youtu.be
Leco V3 Damping Factor At 8 Ohm 100Hz (it falls around 2-3mV when load connected, DF more than 6000)
https://www.youtube.com/watch?v=PLVYt5XFL_c&feature=youtu.be
Input Output Comparator limiter in action on 8/4/2 ohms loading:
https://www.youtube.com/watch?v=_f-4JvsPS6o
Linearity in Hi Freq 1000 to 60000Hz at 450W rms until above 0,05% THD or more appears (red led is flashing):
https://www.youtube.com/watch?v=Ot1jPkRdnQ0
Linearity from 5Hz to 200000Hz at 150 and 100watts/8 ohms:
https://www.youtube.com/watch?v=lSMabN6qM5o&feature=youtu.be
Some pictures during final assembly:
Each module contains balanced to unbalanced stage, IOC limiter (input output comparator limiter), thermal protection, overload and shorted output protection, auto fan based on heatsink temperature DC out protection (triac crowbarr), missing supply rail protection.
This amp is stable 2 ohms, and output current capability is around 50Amps RMS, limited by overload at 39Amps RMS.
Is based on Leco SMPS, custom version for 5,5Kwatts.
I have measured on dummy load as seen in videos (all are in Romanian language but is easy to see and understand what I have done there).
Bottom side
http://s13.postimg.org/6sjsj7qbb/Leco_V3_Bottom.jpg
Top side
http://s13.postimg.org/5g23hbsvr/Leco_V3_Top.jpg
Output stage
http://postimg.org/image/3rmd7y1hr/
Some components mounted
http://postimg.org/image/vhy5nrlsf/
http://postimg.org/image/wy9o5wopb/
http://postimg.org/image/nf4kq6qkv/
On all following tests, the cooling was very poor, one small fan just move the air!
Output current capability on 1 ohm dummy load:
https://www.youtube.com/watch?v=7N9bGpcKHrs
Thermal limiting and main supply current draw from soket wall at 1 ohm load:
https://www.youtube.com/watch?v=vXiCzzpsfnk
Output current capability on 2 ohms and thermal limiting:
https://www.youtube.com/watch?v=7CGDSu9w_IE
Some scope captures:
Sinusoidal 10kHz:
http://postimg.org/image/jjur4dma7/
Triangular 10kHz:
http://postimg.org/image/6jj07xzpr/
Rise-Fall Times on 8 ohms dummy:
http://postimg.org/image/3o5x12vpr/
8 ohms+1uF capacitive load on 10kHz squarewave:
http://postimg.org/image/6m2vus3db/
8 ohms+1uF capacitive load on 10kHz squarewave detail:
http://postimg.org/image/f32e5p827/
Maximum out voltage before clipping 8 Ohm on 10kHz sinusoidal:
http://postimg.org/image/qhyvabken/
Maximum out voltage before clipping 8 Ohm on 10kHz squarewave:
http://postimg.org/image/xmgojcrnz/
Max level then shorted output:
http://postimg.org/image/60dwyo8b3/
And now movies of above scope captures:
Leco V3 rise and fall times +capacitive load:
https://www.youtube.com/watch?v=b3aRnI0nfO4&feature=youtu.be
Leco V3 maximum output on sinusiodal and squarewave signal:
https://www.youtube.com/watch?v=BWNUFg5dgnQ&feature=youtu.be
Leco V3 reactive load 1000Hz 8 Ohm+143uH:
https://www.youtube.com/watch?v=Y4xE_w7JCWE&feature=youtu.be
Leco V3 shorted output and overload: (nice movie!!!)
https://www.youtube.com/watch?v=LH6TSYm7QTI&feature=youtu.be
During tests it was one scope probe uncalibrated, so now is OK
1000Hz probes compensation:
http://postimg.org/image/5ndskds7j/
10000Hz probes compensation:
http://postimg.org/image/wu5ac1pn3/
212Vpp between 10% and 90% in squarewave at 10kHz on 8 ohm load, 3,6uSec rise time:
http://postimg.org/image/jei9mlh5b/
Max out in squarewave at 10kHz capacitive load 1uF on output:
http://postimg.org/image/49qr2tibz/
Clean output at 100Hz on 8 ohm dummy load on output, almost 860 watts (yeloow is output signal, blue is input signal):
http://postimg.org/image/tpumf98un/
Clean output at 100Hz on 2 ohm dummy load on output, almost 2300 watts (yeloow is output signal, blue is input signal):
http://postimg.org/image/d61j6r8y7/
And movies of above scope captures:
1000 and 10000Hz probes compensation:
https://www.youtube.com/watch?v=45bljGxShas&feature=youtu.be
Leco V3 Amplifier Slew Rate Test+1uF Capacitor:
https://www.youtube.com/watch?v=_XRtqYWGOuI&feature=youtu.be
Leco V3 At Output 83-84Vrms/8Ohm Load:
https://www.youtube.com/watch?v=sRbl-yiexkY&feature=youtu.be
Leco V3 At Output 77-78Vrms/4Ohm Load:
https://www.youtube.com/watch?v=vOWOysoFKD0&feature=youtu.be
Leco V3 At Output 67-68Vrms/2 Ohm @ 224Vac
https://www.youtube.com/watch?v=I_Q4Lr38iXk&feature=youtu.be
Leco V3 Damping Factor At 8 Ohm 100Hz (it falls around 2-3mV when load connected, DF more than 6000)
https://www.youtube.com/watch?v=PLVYt5XFL_c&feature=youtu.be
Input Output Comparator limiter in action on 8/4/2 ohms loading:
https://www.youtube.com/watch?v=_f-4JvsPS6o
Linearity in Hi Freq 1000 to 60000Hz at 450W rms until above 0,05% THD or more appears (red led is flashing):
https://www.youtube.com/watch?v=Ot1jPkRdnQ0
Linearity from 5Hz to 200000Hz at 150 and 100watts/8 ohms:
https://www.youtube.com/watch?v=lSMabN6qM5o&feature=youtu.be
Some pictures during final assembly:
Last edited:
