SORRY for my miss-calculation > mistake 😕 I'm irresponsibly going to blame Jack Daniels.No, the RMS is 34.6V for 98V PP, but you will have a voltage drop on the transformer and filter capacitors and the amplifier cannot approach exactly the rail voltage, but a couple of volts less. So 100W RMS/8ohm is some practical max. for unstabilized power supply, probably a little less. Acoustically, the power doubling (100W-200W) is only +3dB, just enough to notice. If you want more power with that supply voltage, you have to go to bridge mode. That 600VA transformer is quite OK for 2x100W/8ohm and let's say 2x150W/4ohm.
"The peak-to-peak value is twice the peak value or 2.828 times the root-mean-square (RMS) value."
98/2.828=34.6
If you are building an amplifier with an output transformer, it will be really big if you want good bass. A lot of iron is needed for 20Hz or lower.
You may notice > that although I made a mistake of 50%, my total power amount does basically allow for TWO channels of aprox. 220 watts69 x 69 = 4761 > divided by 8 ohms = 595 WATTS.
as I stated in post #13.
Thank you for the encouragement 🙂I wish you luck with that project of yours.
OK, I accept the apology. I misunderstood that there will be a transformer at the output. You want a transformer that drives the output stage, that's mostly unknown to me. I've built a lot of amps and other stuff, but never anything like this.
With that 600VA transformer and those voltages -+49V, you have a few options. Single ended AB class stereo 100+100W/8ohm (150+150W/4ohm), in bridge mode mono 300W/8ohm or to go for some D class. The mains transformer should be 1,5x - 2x as powerful as the class AB amplifier. Bigger is better. You can put a smaller transformer and it will work, but trust me, a bigger one gives a better sound. The degree of usefulness of AB class is about 60% and D class about 90%. The power is considered at 4 ohms because there are many speakers whose impedance drops below 4 ohms.
I currently have two DIY amplifiers, a 120+120W/4ohm mains transformer 400VA, and a 220+220W/4ohm mains transformer 800VA.
With that 600VA transformer and those voltages -+49V, you have a few options. Single ended AB class stereo 100+100W/8ohm (150+150W/4ohm), in bridge mode mono 300W/8ohm or to go for some D class. The mains transformer should be 1,5x - 2x as powerful as the class AB amplifier. Bigger is better. You can put a smaller transformer and it will work, but trust me, a bigger one gives a better sound. The degree of usefulness of AB class is about 60% and D class about 90%. The power is considered at 4 ohms because there are many speakers whose impedance drops below 4 ohms.
I currently have two DIY amplifiers, a 120+120W/4ohm mains transformer 400VA, and a 220+220W/4ohm mains transformer 800VA.
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On the website of your countryman Rod Elliott, you have a lot of things nicely explained, with measurements and diagrams. There is a lot written about power supply.
INTERESTING > Thank you.
I guess I'm probably looking at something more like 200 watts with only ONE channel driven.
HIGH POWER is not actually my primary goal of this 'rather strange amplifier idea', but more to keep low power clipping away.
My anticipated rail voltages should still allow for rather high 'DYNAMIC POWER'. [ not continuous power ]
I guess I'm probably looking at something more like 200 watts with only ONE channel driven.
HIGH POWER is not actually my primary goal of this 'rather strange amplifier idea', but more to keep low power clipping away.
My anticipated rail voltages should still allow for rather high 'DYNAMIC POWER'. [ not continuous power ]
https://www.duncanamps.com/psud2/
I use PSUD2 to simulate the power supply. It has performed well so far.
I use PSUD2 to simulate the power supply. It has performed well so far.