Okay this one is giving me some headaches for a month so far.
It works just perfect with NO LOAD attached.
If I hook up a 2 or 4 ohm speaker or a resistor....it distorts, clips and is doing funky stuff well before it's rated output power. What I've noticed, once it draws more than 4.5A of current from my power supply it starts to distort and clip. That's like 50Watts.... Over 4-5Amps of input current is the threshold where all of the weirdness comes from..
I've changed so far - all of the DIP8 OP-AMPS with NE5532, HIP4080, 4013bcn Class D Flip-flop chip, LM833N, 2 x LM293, all of the 8 MOSFETS IRF3710 and some capacitors with a better ones. Cleaned up all of the switches and knobs.
So far nothing has changed even slightly... When input current surpasses 4-5Amps due to me turning the gain up, it goes into very bad distortion You can hear from the speaker and see on the oscilloscope...
If no load is applied - everything is great. I can see the whole voltage swing perfectly fine.
The only thing i've not changed so far are the power supply mosfets and the rectifiers...Maybe the power supply section in the amp cannot supply more current than this or something with the feedback loop in the amplifier section is bad ?! Checked all the diodes and - they read fine. Nothing heats up.
PS: My laboratory power supply can do 0~30volts and 0~20Amps, so it's not my setup...Can this be to a bad relay ?!
It works just perfect with NO LOAD attached.
If I hook up a 2 or 4 ohm speaker or a resistor....it distorts, clips and is doing funky stuff well before it's rated output power. What I've noticed, once it draws more than 4.5A of current from my power supply it starts to distort and clip. That's like 50Watts.... Over 4-5Amps of input current is the threshold where all of the weirdness comes from..
I've changed so far - all of the DIP8 OP-AMPS with NE5532, HIP4080, 4013bcn Class D Flip-flop chip, LM833N, 2 x LM293, all of the 8 MOSFETS IRF3710 and some capacitors with a better ones. Cleaned up all of the switches and knobs.
So far nothing has changed even slightly... When input current surpasses 4-5Amps due to me turning the gain up, it goes into very bad distortion You can hear from the speaker and see on the oscilloscope...
If no load is applied - everything is great. I can see the whole voltage swing perfectly fine.
The only thing i've not changed so far are the power supply mosfets and the rectifiers...Maybe the power supply section in the amp cannot supply more current than this or something with the feedback loop in the amplifier section is bad ?! Checked all the diodes and - they read fine. Nothing heats up.
PS: My laboratory power supply can do 0~30volts and 0~20Amps, so it's not my setup...Can this be to a bad relay ?!
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No, I have a pile of IRF3710. They are from trusted dealer (Farnell). The original ones I've pulled out were also IRF3710 without the N. I know sometimes IRF3710 are causing issues and IRF3710Z are the solution, but I've been using those IRF3710 in other amps with the same design (hip4080) with no problems at all.
So I should order the Z-ones ?!
Where can I find the input from the PRE-AMP section to the amplifier section just to be 100% sure it's not the pre-amp ?!
So I should order the Z-ones ?!
Where can I find the input from the PRE-AMP section to the amplifier section just to be 100% sure it's not the pre-amp ?!
More testing...
Pre-Amp is fine.
This is what the sinewave looks like when I give it a little bit a more thumb - 4ohm subwoofer. This is at 13volts of input and 5amps of current. Sounds terrible
So I will have to ask the client does he wants to invest more money for the irf3710z in this piece of s**t or make it a donor board
Pre-Amp is fine.
This is what the sinewave looks like when I give it a little bit a more thumb - 4ohm subwoofer. This is at 13volts of input and 5amps of current. Sounds terrible
So I will have to ask the client does he wants to invest more money for the irf3710z in this piece of s**t or make it a donor board
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Quick update.
Friend of mine blown up his amplifier couple of days ago. It is based again on hip4080 and IRF3710 so I very curious to see what's going on.
Power supply was blown, output section too.
So I've fixed the PS section, replaced the hip4080 (the one in his amp was totally blown) and I've fitted again IRF3710 from the same pile I used for the Hifonics.
What a weird one...the gate drive to to the output mosfets is great (same for the 2 banks comparing low to low / high to high) but one of the banks does NOT work correctly. Like perfect gate drive comes in - sh*t comes out...
At the output the sinewave is cut out, clipped at it's top part way more earlier that it's supposed to be...Again at approximately the same level of input power as the Hifonics...
I'm starting to suspect it's the stupid irf3710.... For sure i will order now the Z version.
Friend of mine blown up his amplifier couple of days ago. It is based again on hip4080 and IRF3710 so I very curious to see what's going on.
Power supply was blown, output section too.
So I've fixed the PS section, replaced the hip4080 (the one in his amp was totally blown) and I've fitted again IRF3710 from the same pile I used for the Hifonics.
What a weird one...the gate drive to to the output mosfets is great (same for the 2 banks comparing low to low / high to high) but one of the banks does NOT work correctly. Like perfect gate drive comes in - sh*t comes out...
At the output the sinewave is cut out, clipped at it's top part way more earlier that it's supposed to be...Again at approximately the same level of input power as the Hifonics...
I'm starting to suspect it's the stupid irf3710.... For sure i will order now the Z version.
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