I bought a 24v/21a Mean Well smps from TRC Electronics a few months ago for my diy audio system. TRC seems like a major online distributor/seller of various smps units. ~500w was the highest power I could reliably find anywhere online, amateur searching likely the culprit.
At the time, 500w seemed dandy, I had 50x2 rms and 110x2 rms amplifier boards for an active bookshelf build. A little over 300w rms plus the inefficiencies with a hundred watts leftover to expand one day.
Big surprise, I’m considering expanding lol. Imagine now, I want to swap my svc 4 ohm bookshelf woofers with a set of monster 5-1/2 4ohm dvc subwoofers. So now I’m looking at two 110x2 rms amplifier boards and one 50x2 rms, 24v/21a can’t do it. Add the center and surround channels in a 5.0 and I’m needing just over 700w of power supply.
I realize that the maximum power demand only applies at absolute maximum volume output but when I’m home before Alison, I sometimes have the urge to shake the house. I’m trying to do without any external subwoofer as a personal design challenge and for aesthetics. Having the bookshelves be the low frequency source also allows me to have two subwoofer locations for room modes.
I see 2kw amplifier boards out there but never a 3kw power supply. How do we produce power over the pedestrian 500w supply units that seem to be the consumer limit?
The 5-1/2 (monster) subwoofers are the Dayton Epique in a small bookshelf with the Tang Band 3” bamboo fullrange. I’m dsp’ing the snot out of the woofers to shelve off the midbass to allow the lower bass to shine. Essentially I’m making the bookshelfs sensitivity in the high 70’s because of the cuts. Winsld shows two Epique 5” woofers will produce sufficient low frequency spl for my liking in a townhouse, but they need power to get there.
At the time, 500w seemed dandy, I had 50x2 rms and 110x2 rms amplifier boards for an active bookshelf build. A little over 300w rms plus the inefficiencies with a hundred watts leftover to expand one day.
Big surprise, I’m considering expanding lol. Imagine now, I want to swap my svc 4 ohm bookshelf woofers with a set of monster 5-1/2 4ohm dvc subwoofers. So now I’m looking at two 110x2 rms amplifier boards and one 50x2 rms, 24v/21a can’t do it. Add the center and surround channels in a 5.0 and I’m needing just over 700w of power supply.
I realize that the maximum power demand only applies at absolute maximum volume output but when I’m home before Alison, I sometimes have the urge to shake the house. I’m trying to do without any external subwoofer as a personal design challenge and for aesthetics. Having the bookshelves be the low frequency source also allows me to have two subwoofer locations for room modes.
I see 2kw amplifier boards out there but never a 3kw power supply. How do we produce power over the pedestrian 500w supply units that seem to be the consumer limit?
The 5-1/2 (monster) subwoofers are the Dayton Epique in a small bookshelf with the Tang Band 3” bamboo fullrange. I’m dsp’ing the snot out of the woofers to shelve off the midbass to allow the lower bass to shine. Essentially I’m making the bookshelfs sensitivity in the high 70’s because of the cuts. Winsld shows two Epique 5” woofers will produce sufficient low frequency spl for my liking in a townhouse, but they need power to get there.
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Here's 24VDC 650W for $80:
https://www.allelectronics.com/item/ps-24655/24-vdc-650-watt-power-supply/1.html
https://www.allelectronics.com/item/ps-24655/24-vdc-650-watt-power-supply/1.html
Bear in mind that you will need higher DC voltage as well as higher power.
And you can go dual mono for the power amplifier if necessary.
And you can go dual mono for the power amplifier if necessary.
How big is your listening area?
Bear in mind that sound levels above 110dB can result in long term hearing loss.
So work from there, 500 W RMS sounds enough for me.
Bear in mind that sound levels above 110dB can result in long term hearing loss.
So work from there, 500 W RMS sounds enough for me.
With a single supply of 24V (so the maximum possible peak to peak output swing = 24V) the max output is 8.5 Vrms.
Into 8 ohms, that is 8.5^2/8 = 9 watts.
For 110W into 8 ohms, the rms output voltage must be found with the equation: 110 = V^2 / 8
or V = sqrt (880) = 29.7 Vrms and that is over three times higher.
With a single supply amplifier output of 29.7 Vrms you need a supply larger than 2.818 x 29.7V = 83.9 VDC
This should not be surprising, since many dual supply amplifiers have +/-40V supplies.
If the power supplies have isolated outputs, you could use two in series to double the DC voltage.
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Lots of choices here - play around with the filters:
https://www.newark.com/w/c/power-li...kw|4.8kw|4.968kw|5.04kw|9.6kw|9.936kw|10.08kw
Brian
https://www.newark.com/w/c/power-li...kw|4.8kw|4.968kw|5.04kw|9.6kw|9.936kw|10.08kw
Brian
It would be good to define what your different amps are. I’m guessing they are Class D and operate off of single voltage supplies. If that’s the case, I would imagine your 24V 21A SMPS unit would be plenty if you used one per channel (one per speaker).
There are some inexpensive 24-48 VDC SMPS out there that perform well in audio. If you need several of them, that could end up working.
There are some inexpensive 24-48 VDC SMPS out there that perform well in audio. If you need several of them, that could end up working.
I’m running my mowing route so I’ll try to be concise. The room is about 13’x13’. I’m using mostly Dayton Audio kabd class d dsp boards. The power is needed from wondom 2x160 boards which are rated at about 110x2 rms. The wondom calls for about 18v-36v single power supply.
Currently I’m powering a set of bookshelves with an anarchy 5-1/2” 4 ohm in each in .24cf sealed. I’m applying a high shelf filter to attenuate the midbass and allow more sub 50hz to shine. The modeling shows approaching xmax at around a hundred wpc. Just seems 24v won’t do 100 watts and the board is rated to 36v.
The Anarchy’s theoretically should suffice for my needs but if not I’ll be looking to upgrade to the Dayton Epique 5-1/2” dual 4 ohm subwoofers, which I’ve had great success in my car with the 7’s. If running the Epiques, I’d run each Wondom channel to each 4 ohm coil as I have two 2x160’s on hand. After eq cuts it looks like a little over 200 watts per epique would attain near xmax , which would be useful for headroom id think.
With electrical losses it would seem like the pair of Epique’s would gobble up all the available 500w from the power supply, granted I could even get the full 110wpc @24v. Then there’s the 3” tang band bamboos that need power as well as the center channel and surrounds in the 5.0 theater I’m working on. If the Anarchys suffice I will be fine with the 500w supply, if 24v gets me to 100wpc on my bookshelf woofers.
Currently I’m powering a set of bookshelves with an anarchy 5-1/2” 4 ohm in each in .24cf sealed. I’m applying a high shelf filter to attenuate the midbass and allow more sub 50hz to shine. The modeling shows approaching xmax at around a hundred wpc. Just seems 24v won’t do 100 watts and the board is rated to 36v.
The Anarchy’s theoretically should suffice for my needs but if not I’ll be looking to upgrade to the Dayton Epique 5-1/2” dual 4 ohm subwoofers, which I’ve had great success in my car with the 7’s. If running the Epiques, I’d run each Wondom channel to each 4 ohm coil as I have two 2x160’s on hand. After eq cuts it looks like a little over 200 watts per epique would attain near xmax , which would be useful for headroom id think.
With electrical losses it would seem like the pair of Epique’s would gobble up all the available 500w from the power supply, granted I could even get the full 110wpc @24v. Then there’s the 3” tang band bamboos that need power as well as the center channel and surrounds in the 5.0 theater I’m working on. If the Anarchys suffice I will be fine with the 500w supply, if 24v gets me to 100wpc on my bookshelf woofers.
24 volts simply limits the power to 72 watts, before considering any losses at all. Even if it was a 2kW supply. What you DO need to get that 72 watts at low frequency is a 6 amp (ie, 150W) supply. For each channel. Want more? You have to bump up the voltage (and current), period. 110 watts requires a 30 volt supply.
All this assumes full bridge operation, which most of those single-supply class D modules are. And losses can be fairly minimal, limited by just Rds(on) in the hexfets, which can be tens of milliohms. Switching losses will cause a bit of extra current draw, but don‘t scrub much off the available power.
All this assumes full bridge operation, which most of those single-supply class D modules are. And losses can be fairly minimal, limited by just Rds(on) in the hexfets, which can be tens of milliohms. Switching losses will cause a bit of extra current draw, but don‘t scrub much off the available power.
I have a variable boost converter but I’ve been hoping to avoid adding more components. Also I’m not perfect confident about adjusting the current potentiometer on it.
Boost Voltage Converter, 400W Step-up Converter Constant Current Power Supply Module DC 8.5V-50V 15A to DC 10V-60V 12A Boost Converter https://a.co/d/37On7h7
Boost Voltage Converter, 400W Step-up Converter Constant Current Power Supply Module DC 8.5V-50V 15A to DC 10V-60V 12A Boost Converter https://a.co/d/37On7h7
I still think that 500 W is adequate for a 13 x 13 foot room, unless it is treated, or you have hearing loss.
Or you like your music body thumping loud.
Or you like your music body thumping loud.
Perhaps, (hopefully), 500w smps will be fine.
The problem that just won’t go away is the input voltage vs wattage output boogeyman. Some have said that running 4 ohm speakers with 24v powered amp will do rated power. Some have said it'll do a bit less. I watched a video of a guy testing the TDA7498E chip in a cheap amazon board and getting ~50wpc @ 24v vs ~110wpc @36v. If I’m going to end up with around 50wpc anyway, I may as well use the 50w and 100w boards rated at 24v that are half the size.
I suppose it’s time to start looking into properly setting up the boost converter to get that 160x2 board flowing.
The problem that just won’t go away is the input voltage vs wattage output boogeyman. Some have said that running 4 ohm speakers with 24v powered amp will do rated power. Some have said it'll do a bit less. I watched a video of a guy testing the TDA7498E chip in a cheap amazon board and getting ~50wpc @ 24v vs ~110wpc @36v. If I’m going to end up with around 50wpc anyway, I may as well use the 50w and 100w boards rated at 24v that are half the size.
I suppose it’s time to start looking into properly setting up the boost converter to get that 160x2 board flowing.