Can somebody give me a little refresher on power supply design ?
The amp requires +/- 56-59V rails. Currently, I have the Victoria Magnetics 80VCT 6A toroid connected to the BR, with 1 Panasonic TUP 80V 12,000uF on the + and - rails for a total of 24,000uF.
The speakers I am really considering are the Martin Logan Aerius i's or maybe a larger model if i've got the cash at the time. As you may know these speakers exhibit a 4 ohm load at low frequencies which drops below a 2 ohm load at higher freq's. I do not intend on bi amping these.
My amplifier will not current limit until just below 2 ohms, but I am a bit worried that the power supply isn't sufficient for a true doubling from 8-4-2 ohms. (120-240-480wpc.)
I have thought about just buying another of the same toroid and making a true dual monoblock design. Will this be sufficient? It seems to me that if I wanted 480wpc @ 2 ohms I would be looking at xformers in the 900-1100VA range for each channel? Is this unreasonable? Do I really need to double my power to a 2 ohm load? Leach suggested using a toroid with two secondaries wired in parallel. Is this reasonable? Expensive?
On to filter capacitors. I have seen several people mention the've got 50,000uF or more per channel of their amp. Are there any downsides to running a lot of filter capacitance other than cost and the gigantic current rush at turn on? What is considered overkill?
Is there going to be much of an improvement if I use better quality filter caps? I know mine are about as cheap as they come.
Lastly, how much does the voltage drop from the toroid through the BR and caps ? all my audio book says is 'account 10-15%') does it get any more scientific?
I went into this project blindly and am now trying to fix some of my mistakes. ceramic caps! haha.
A bit off subject, but with electrostatic speakers, is the unusual impedance curve there because of lower high frequency sensitivity? Or is it an inherent aspect of electrostats and I need to be concerned that my highs are 3-6dB louder than the rest of the spectrum?
Thanks a lot!
jt
The amp requires +/- 56-59V rails. Currently, I have the Victoria Magnetics 80VCT 6A toroid connected to the BR, with 1 Panasonic TUP 80V 12,000uF on the + and - rails for a total of 24,000uF.
The speakers I am really considering are the Martin Logan Aerius i's or maybe a larger model if i've got the cash at the time. As you may know these speakers exhibit a 4 ohm load at low frequencies which drops below a 2 ohm load at higher freq's. I do not intend on bi amping these.
My amplifier will not current limit until just below 2 ohms, but I am a bit worried that the power supply isn't sufficient for a true doubling from 8-4-2 ohms. (120-240-480wpc.)
I have thought about just buying another of the same toroid and making a true dual monoblock design. Will this be sufficient? It seems to me that if I wanted 480wpc @ 2 ohms I would be looking at xformers in the 900-1100VA range for each channel? Is this unreasonable? Do I really need to double my power to a 2 ohm load? Leach suggested using a toroid with two secondaries wired in parallel. Is this reasonable? Expensive?
On to filter capacitors. I have seen several people mention the've got 50,000uF or more per channel of their amp. Are there any downsides to running a lot of filter capacitance other than cost and the gigantic current rush at turn on? What is considered overkill?
Is there going to be much of an improvement if I use better quality filter caps? I know mine are about as cheap as they come.
Lastly, how much does the voltage drop from the toroid through the BR and caps ? all my audio book says is 'account 10-15%') does it get any more scientific?
I went into this project blindly and am now trying to fix some of my mistakes. ceramic caps! haha.
A bit off subject, but with electrostatic speakers, is the unusual impedance curve there because of lower high frequency sensitivity? Or is it an inherent aspect of electrostats and I need to be concerned that my highs are 3-6dB louder than the rest of the spectrum?
Thanks a lot!
jt