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RE: I'm Bored. A-S MA-1 amp tweaks and experiments

27,000 uF!!! Wow. I did not know Ralph had taken it that far. I am using 14,000uF per phase, and the bass response is already excellent into a relatively high impedance load.

Here are two ideas, neither of which may fit into your chassis': Instead of one honkin' 27,000uF cap, you could try stringing in parallel a bunch of smaller value caps to achieve the same or nearly the same capacitance. In theory, smaller value lytics would give up their charge more quickly to the load. I did that with my amps; I use a total of 14 X 2000uF/200V Panasonic TS-ED caps per monoblock, but my chassis are the huge old style MA2 type, and even then it was somewhat of a trick to fit them. As to bypass, the bigger the value of film cap you can fit in there, the better. Also, you might bypass the total capacitance with some Russian teflons, any values from 0.47uF down to .01uF. The Russian SSG silver mica caps are also fantastic, can be had in values from 0.12 uF down to a few thousands of pF.

Also, I use a tweak originated by Paul Speltz. I inserted very small value resistors (<0.5 ohm) between the first 2000uF cap in each bank and the next cap, and then even smaller resistors between the second and third 2000uF caps in each bank, like 0.21R or 0.1R. Since the resistance is so low, 5W rated ones are OK. Put the resistors on the pos AND neg poles of the capacitors. (If you can find the old ASOG archives, Paul put us a schematic for this on that site.)


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