I want to build 4ch amplifier with D25 module. I have built 4ch pre amplifier with ch1-2 and ch 3-4 parallel or btl. I use the 8 ohm load modules. But i would like to set up d25 operation with 4 and 8 ohm loads. I have modified transformer of behringer ep4000, he give me so much power but very very heavy. I want to change transformer with smps. I want to build smps big smps, but I think it's too expensive and dangerous, so think so build 2 small smps, 1smps drive 2 pcs of d25. I think that to drive 1 pcs D25 with load 8ohm, with 62-64 volt effective, well fit 3.5 amps and 7 amps peak, for two d25 7-8 continuous amps and peak 14-15 ...... this At maximum power ..... but i do not want to get to the maximum power, a little less ..... the problem is that using d25 in 4ohm load, smps power is inadequate. I would like to build smps to use 4 e8 ohm load. I have inserted in the previous post the electric smps scheme 900watt in +/- 70v. It give a peak of 1100-1200watts. Can it be a good solution?
My L25D stereo amp finaly works.
I recommand active cooling or larger heatsinks if you power the L25D module above 70V, propably its always a good idea.
I burned 3x IRFB4020 before i finally solved the problem with a slow fan.
The modules sound is pretty good, but compared with other class D amps the irs2092 builds are expensive and inefficient. For future porjekts i think twice about the power i really need and choose TPA3116 modules if possible.
I recommand active cooling or larger heatsinks if you power the L25D module above 70V, propably its always a good idea.
I burned 3x IRFB4020 before i finally solved the problem with a slow fan.
The modules sound is pretty good, but compared with other class D amps the irs2092 builds are expensive and inefficient. For future porjekts i think twice about the power i really need and choose TPA3116 modules if possible.
You did not mention what the condition was you burned it with. Full throttle?
Excuse me, 55 bucks are expensive? What other modules with comparable specs are cheaper? How do you gauge efficiency?
-h
Burned with +-75V supply voltage on true 8 Ohm speaker (above 9 ohm DC resitance) with moderate volume after 45 min. My Case a recycled old amp with vents for heat dissipation.
True, its not expensive compared for what you get. I think in most cases the tpa 3116 has enought power and can be powered with cheap 24V powersupply.
The L25D modules have standby loss ober 10W/module. Thats inefficient compared to the tpa 3116. Of cause the IRS has much more power, so the comparsion is propably unfair.
I never mentioned a difference in the soundquality, but thats propably just me.
True, its not expensive compared for what you get. I think in most cases the tpa 3116 has enought power and can be powered with cheap 24V powersupply.
The L25D modules have standby loss ober 10W/module. Thats inefficient compared to the tpa 3116. Of cause the IRS has much more power, so the comparsion is propably unfair.
I never mentioned a difference in the soundquality, but thats propably just me.
Hmm. Although this is within the marks, you probably are pushing the envelope with that high a supply.
Moderate volume is probably not much power-wise, since you can produce 90dB with one watt on a moderate speaker. So it can´t be the power.
Those modules produce power for the controller directly from the rails with dropper resistors which inevitably dissipates power. This is probably what you encounter as standby loss. Some slightly more elaborate scheme (albeit inevitably more pricey...) would cater for this.
-h
Moderate volume is probably not much power-wise, since you can produce 90dB with one watt on a moderate speaker. So it can´t be the power.
Those modules produce power for the controller directly from the rails with dropper resistors which inevitably dissipates power. This is probably what you encounter as standby loss. Some slightly more elaborate scheme (albeit inevitably more pricey...) would cater for this.
-h
Since you have to drive 4ohms, L30D board from aliexpress seller ZOE_TSANG. This seller ir recomended by author of these boards.
L30D/300 850W Mono Class D IRS2092 IRFB4227 IRAUDAMP9 Amplifier completed board by LJM-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
L30D/300 850W Mono Class D IRS2092 IRFB4227 IRAUDAMP9 Amplifier completed board by LJM-in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
)I exchanged my Transformer with a 65V switching PSU board. The Bords are much cooler now. I haven't expected such an impact on the heat dissapation, cause the Board is rated up to 80V. Seems like the 80V is a limited time surival limit and the recommanded 70V shouldn't be exeeded.
I've got two of the L20D boards on the way along with a 500W ~ +/-73Vdc SMPS. I write ~ as the SMPS is good for 110-240VAC, the stated output of +/-70Vdc is with a 220Vac mains where as I have 230Vac mains.
My question has to do with power supply capacitors, as I understand it, SMPS supplies aren't to fond of big capacitors? (Between the supply and the amp modules)
Those of you who use SMPS supplies with these boards, how have you done?
My question has to do with power supply capacitors, as I understand it, SMPS supplies aren't to fond of big capacitors? (Between the supply and the amp modules)
Those of you who use SMPS supplies with these boards, how have you done?
My amp design (see my gallery) uses seven L15D 150W modules running off two +/-55V SMPS PSUs. I replaced the two buffer electrolytic caps on each of the L15D boards with Rubycon 820uF 63V caps (for improved bass), but haven't added any other caps between the supply and the modules, and have had no issues whatsoever. Sounds fantastic at any volume.
So I'm not sure that any additional caps are necessary. However, you might want to consider using a phase inverter on the input one of the channels (and reversing the corresponding speaker polarity) to avoid any possibility of bus pumping at low frequencies, which can be an issue with class D amps. Slides 13-15 in my gallery show the schematic, board layout and connections for the phase inverters I built.
So I'm not sure that any additional caps are necessary. However, you might want to consider using a phase inverter on the input one of the channels (and reversing the corresponding speaker polarity) to avoid any possibility of bus pumping at low frequencies, which can be an issue with class D amps. Slides 13-15 in my gallery show the schematic, board layout and connections for the phase inverters I built.
I think that would be overkill, and each amp could still cause some bus pumping on its PSU.
Phase inversion on one channel in a stereo configuration is recommended in the IRAUDAMP7 Reference Design, and is actually included in that design for a single stereo half-bridge / mono full bridge switchable board. That's why I included phase inverters in my design, and also slightly increased the bus capacitors. Bus pumping is described on P26 of the IRAUDAMP7 Reference Design, and the inverter schematic is shown on P27 and P32.
Having said all that, I don't actually know how big a problem bus pumping is at normal listening volumes - it would certainly be worse in a subwoofer application, as it is happens at low frequency, high output. Someone else might have a view on this.
Perhaps you could try it first without a phase inverter, but measure the + and - voltages across the the PSU at all listening levels and for a reasonable time period (I use cheap 100W 8 ohm resistors from Aliexpress instead of speakers for testing, to save my ears and keep peace with the family and the neighbours!), and if either bus voltage starts to rise then you could add a phase inverter to one channel later.
By the way, two other modifications I made were:
- to replace the resistor that controls switching frequency with a multi-turn trimpot so I could adjust the switching frequencies on each channel to less than 5Hz of each other, to avoid interference between channels (see reference Design P21-22), and
- to replace all the 22uF electrolytic caps with Elna Silmic II caps, as these are said to give a smoother sound.
I wanted to get the best possible sound from these amps, so I thought it was worth the extra time and trouble follow the reference design recommendations, and for these other mods. And I am blown away by the smooth and effortless sound quality, as are my somewhat critical friends who were doubtful that a home-built class-D amplifier could sound this good!
Good luck with your build.
I ordered a 500VA 2x48Vac transformer from toroidy, the potted audio labeled kind.
I figured I may use it for this build, or if I'm happy with the switch mode power supply, I'm sure there are other amp projects that I can use it for down the road.
Not sure if it, and PS capacitors, will fit the enclosure I have on the way for the L20D build.
enclosure
I figured I may use it for this build, or if I'm happy with the switch mode power supply, I'm sure there are other amp projects that I can use it for down the road.
Not sure if it, and PS capacitors, will fit the enclosure I have on the way for the L20D build.
enclosure