Hi Apex and Hi everybody,
I'm back to the forum after 2 years I guess
Apex, thanks for the Amp. I always followed you on facebook
I'm gonna try this soon. I'm just checking whether the parts are available here in Sri Lanka.
I can't find a proper transformer to get +/- 75 or higher.
Can I couple 2 x 28-0-28/8A AC transformers that is 56 AC each rail to get +/-80
cheers!
I'm back to the forum after 2 years I guess
Apex, thanks for the Amp. I always followed you on facebook
I'm gonna try this soon. I'm just checking whether the parts are available here in Sri Lanka.
I can't find a proper transformer to get +/- 75 or higher.
Can I couple 2 x 28-0-28/8A AC transformers that is 56 AC each rail to get +/-80
cheers!
Hi Apex and Hi everybody,
I'm back to the forum after 2 years I guess
Apex, thanks for the Amp. I always followed you on facebook
I'm gonna try this soon. I'm just checking whether the parts are available here in Sri Lanka.
I can't find a proper transformer to get +/- 75 or higher.
Can I couple 2 x 28-0-28/8A AC transformers that is 56 AC each rail to get +/-80
cheers!
D200 will work fine with +/-40V (28-0-28v AC), +/-80V is maximum and I suggest increase PSU voltage after test amp with +/-35V.
Regards
My D200 is in progress..
But I doubt that I can find IRFB4227 in here.
I have IRF540N, IRFZ48N, IRF840 with me. I Can also find IRFP numbers. What is the best out of these instead of IRFB4227.
How can I change the frequency for that one for the best result?
Please mention the components to be changed.
Thanks
But I doubt that I can find IRFB4227 in here.
I have IRF540N, IRFZ48N, IRF840 with me. I Can also find IRFP numbers. What is the best out of these instead of IRFB4227.
How can I change the frequency for that one for the best result?
Please mention the components to be changed.
Thanks
Attachments
hi sir apex
i was used bav21 but my problem not solved
what is the gate resistor for irf640n ?
thanks
irs3000 problem!!!
hi andrew
i tried irs3000. unfortunately it has problem just like what IRS said
oscillation can't start without input signal and its LED also is off
every thing is just like Mr IRS video
whats this problem for?
its assemble problem or design?
hi andrew
i tried irs3000. unfortunately it has problem just like what IRS said
oscillation can't start without input signal and its LED also is off
every thing is just like Mr IRS video
whats this problem for?
its assemble problem or design?
Attachments
i tried D200 yesterday, its happy to say it works
it's Mackie SRM450 active speaker amp with a change in level shifter and designed base on IRAUDAMP1.
this topography needs to be under load and a input triger to start oscillation at first and in a active speaker like SRM450 there is no problem, because the driver is always connected to the amp but for general use it needs a load resistor as permanent.
i used a 1k/2W resistor and it seems proper.
as apex said uf4004 had to change with BAV21 or MUR120.
Note that frequency 430KHz is obtained by the using IRFB31N20D as output transistor and it change by changing the transistor
for IRF640N the frequency is about 170KHz that is not good enough.
the 510ohm resistor(R183) can control the frequency (just like what R27 do in IRAUDAMP1) and u can change it by a 5kohm variable pot to set the frequency.
as u can see i use IRF640N and set the frequency to 413KHz.
the output pwm is not quite sharp and excellent but Fortunately its stable enough and not a overshoot edge.
Regards,
it's Mackie SRM450 active speaker amp with a change in level shifter and designed base on IRAUDAMP1.
this topography needs to be under load and a input triger to start oscillation at first and in a active speaker like SRM450 there is no problem, because the driver is always connected to the amp but for general use it needs a load resistor as permanent.
i used a 1k/2W resistor and it seems proper.
as apex said uf4004 had to change with BAV21 or MUR120.
Note that frequency 430KHz is obtained by the using IRFB31N20D as output transistor and it change by changing the transistor
for IRF640N the frequency is about 170KHz that is not good enough.
the 510ohm resistor(R183) can control the frequency (just like what R27 do in IRAUDAMP1) and u can change it by a 5kohm variable pot to set the frequency.
as u can see i use IRF640N and set the frequency to 413KHz.
the output pwm is not quite sharp and excellent but Fortunately its stable enough and not a overshoot edge.
Regards,
Attachments
i tried D200 yesterday, its happy to say it works
it's Mackie SRM450 active speaker amp with a change in level shifter and designed base on IRAUDAMP1.
this topography needs to be under load and a input triger to start oscillation at first and in a active speaker like SRM450 there is no problem, because the driver is always connected to the amp but for general use it needs a load resistor as permanent.
i used a 1k/2W resistor and it seems proper.
as apex said uf4004 had to change with BAV21 or MUR120.
Note that frequency 430KHz is obtained by the using IRFB31N20D as output transistor and it change by changing the transistor
for IRF640N the frequency is about 170KHz that is not good enough.
the 510ohm resistor(R183) can control the frequency (just like what R27 do in IRAUDAMP1) and u can change it by a 5kohm variable pot to set the frequency.
as u can see i use IRF640N and set the frequency to 413KHz.
the output pwm is not quite sharp and excellent but Fortunately its stable enough and not a overshoot edge.
Regards,
What is rail voltage on your amp?
Regards
its about -/+47v dc
PG0208 core from Behringer amp is working better on this amp as you said.
T106-2 red clear core warm up a little in this frequency.
regards,
Amp works
I assembled carefully. It worked at once.
Tested without a heatsink so I couldn't run so long. FETs heat up quickly.
Used 16 ohms loudspeaker for the test. I did not increase the input volume as no heatsink on FETs
Supply voltage: +/- 40
Outputs: IRF640N
used: BAV21, T106-2 filter. 10R/5W, 2K2/5W, BD241C 400v rated capacitors at output stage. paralleled 2 x 0.1ohms/2W resisters to get 0.05ohms,
I couldn't find 510R resister so combined 390R + 120R.
** May be too many turns on T106-2. I'm gonna reduce and test later.
Everything is cool except outputs. I need to minimize the heat and increase the voltage upto +/-90. So need your help.
So far, the best class D amp I have tested!!!
Thanks Apex
** One more thing: The PCB is too much tidy up. Output stage needs more space to assemble. Mounting components are not easy specially the heatsink on FETs. I appreciate if you can re-design that area and publish the layout for us please.
I assembled carefully. It worked at once.
Tested without a heatsink so I couldn't run so long. FETs heat up quickly.
Used 16 ohms loudspeaker for the test. I did not increase the input volume as no heatsink on FETs
Supply voltage: +/- 40
Outputs: IRF640N
used: BAV21, T106-2 filter. 10R/5W, 2K2/5W, BD241C 400v rated capacitors at output stage. paralleled 2 x 0.1ohms/2W resisters to get 0.05ohms,
I couldn't find 510R resister so combined 390R + 120R.
** May be too many turns on T106-2. I'm gonna reduce and test later.
Everything is cool except outputs. I need to minimize the heat and increase the voltage upto +/-90. So need your help.
So far, the best class D amp I have tested!!!
Thanks Apex
** One more thing: The PCB is too much tidy up. Output stage needs more space to assemble. Mounting components are not easy specially the heatsink on FETs. I appreciate if you can re-design that area and publish the layout for us please.
Attachments
I assembled carefully. It worked at once.
Tested without a heatsink so I couldn't run so long. FETs heat up quickly.
Used 16 ohms loudspeaker for the test. I did not increase the input volume as no heatsink on FETs
Supply voltage: +/- 40
Outputs: IRF640N
used: BAV21, T106-2 filter. 10R/5W, 2K2/5W, BD241C 400v rated capacitors at output stage. paralleled 2 x 0.1ohms/2W resisters to get 0.05ohms,
I couldn't find 510R resister so combined 390R + 120R.
** May be too many turns on T106-2. I'm gonna reduce and test later.
Everything is cool except outputs. I need to minimize the heat and increase the voltage upto +/-90. So need your help.
So far, the best class D amp I have tested!!!
Thanks Apex
** One more thing: The PCB is too much tidy up. Output stage needs more space to assemble. Mounting components are not easy specially the heatsink on FETs. I appreciate if you can re-design that area and publish the layout for us please.
FETs and BD241C must have heatsinks. D200 is made as first class D amp for test and expirience, I will made new amp (pcb).
Regards
sound is good. It seems to have a good frequency response because of 400Khz pwm. no distortion can be heard even in high frequency and low frequency response is so good.
output transistors works cool after 3 hours work under 4ohm load and it means good switching
i still haven't the frequency response for better analyze but i'll get it.
i used ETD and RM type before for other d-class amp but they are not as good as toroid cores. i think output sound of toroid cores is warmer. (it's just my experiment
)most professional designers i've ever seen (like QSC crown or Mackie) also use toroid type cores.
what type u use?
what do you think about protection, this protection is good in over current fault occurs by speaker but i think if the output connected to any other ground (like shielded buddy ) and over current fault happen, it will not work,
sound is good. It seems to have a good frequency response because of 400Khz pwm. no distortion can be heard even in high frequency and low frequency response is so good.
output transistors works cool after 3 hours work under 4ohm load and it means good switching
i still haven't the frequency response for better analyze but i'll get it.
i used ETD and RM type before for other d-class amp but they are not as good as toroid cores. i think output sound of toroid cores is warmer. (it's just my experiment
most professional designers i've ever seen (like QSC crown or Mackie) also use toroid type cores.
what type u use?
what do you think about protection, this protection is good in over current fault occurs by speaker but i think if the output connected to any other ground (like shielded buddy ) and over current fault happen, it will not work,
Hypex and clones did not use toroid type cores