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Filter capacitance-how does it relate to amplifier performance?

I have a Unison Research Due amplifier that drives my Totem Forest Signature with ease. It has 100wpc in 8ohm and 180wpc in 4ohm. It has a filter capacitance of 80,000uF

I previously had a Atoll in100 amplifier 100wpc in 8 ohm, 140wpc in 4 ohm Capacitance of 31,474 uFMoving up the Atoll line the in200 has 120wpc in 8 ohm and 200wpc in 4 ohm and filter capacitance of 62,000uF
The Atoll in300 has 150wpc in 8 ohm and 260 Epcot in 4 ohm with a filter capacitance of 81,600uF. These also had no trouble driving my speakers.

My understanding of capacitors is that they store energy. Does this mean that my Due amplifier is just as powerful  as the on paper more powerful Atoll in300?

For comparison sake with my Due amplifier I demoed a Plinius Hautonga integrated amp with 200wpc in 8 ohm and 280wpc in 4 ohm. I did not hear any appreciable difference in bass or other frequencies.

So 3 questions.

1) Is my Due amplifier much more powerful than the wpc  indicates?
2) How does filter capacitance relate to power in an amplifier?

3) Why do manufacturers rarely publish this spec? I could only find a few examples.

Thanks
traceyc

Showing 3 responses by xenolith

xenolith's avatar
xenolith
166 posts
 
Thanks George!  I really think a lot of people have really missed the boat with Matrix 801s, myself included for a long time....the oft repeated 'need for big solid state amplification' just isn't so in my experience...and in fact, is contraindicated for best sound in my experience.

Still puzzled by the total of 94mF capacitance in the power supply of these killer amps...

 
xenolith's avatar
xenolith
166 posts
 
Hoping Ralph will comment on the situation with my custom built 100 watt 4 x KT77 monoblocks (built by Charlie Cocci): when I took off the bottom plate to admire Charlie's work, I was shocked to see only 2 x 47mF 630 volt capacitors in the power supply section.  By comparison, my Jon Soderberg updated (200 w/ch.) Threshold Stasis 2 has 4 x 63,000mF capacitors in the power supply section! 

When I asked Charlie about this, he told me (paraphrasing) 'When you've got enough voltage, you don't need as much capacitance.'  I'm thinking that this may be a statement of the Work equation that Ralph posted.  

By the way, the tube amps absolutely kill the Threshold in bass response...much better control of the big 12" woofers in the NorthCreek crossovered Matrix 801 S2s and what sounds like an extra half octave of response.  The tube amps kill the Threshold in every other way as well, but the bass response was a real surprise.  

Thanks for any insight from anyone into how this can be!
xenolith's avatar
xenolith
166 posts
 
I apologize if I’m veering this thread off course, but wanted to add that the power supply in the Cocci tube amps is unregulated in order to provide speedy power delivery to the audio circuit, while the input section of the audio circuit includes a 3 Henry choke and the output section of the audio circuit includes a 8 Henry choke. Massive power and (200 watt rated) output transformers and Dueland VSFs in the audio circuit. I believe the high speed and great frequency extension of these amps are products of this strategy of quick power delivery to the audio circuit and ’smoothing’ through inductance rather than capacitance.

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