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Hello fellow inmates. I'm bored.
I don't know when to leave well enough alone. My system sounds amazing.
So;
I opened up the underside of my MA-1 mk3.2 amps (Silver Editions upgraded). I saw multistrand wire running from the monster (27,000uF caps) to the binding posts. I don't like multistrand wire, so I changed it to solid core. Slightly smoother in the mids and highs, so it stays.
Now I am looking at the bypass (ripple current) caps connecting the +ve to -ve posts of each big cap. This capacitor is 1uF. What are the pros and cons to raising or lowering this value?
Bored Billy
Follow Ups:
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.)
Hi,Attached URL to the mentioned PSU modification.
Edits: 03/06/14
nt
OK, that experiment worked.
I don't know if it was the increase in capacitance from 1uF to 1.2uF. It may have been the Clarity MA. There was both an increase in resolution and body in the midrange. It could have been the Vishay MKP 1837 added. I am happy.
Now comes something a little harder;
My amps have 1,200uF of power supply capacitance per amp. This is by way of 12 100uF caps, 6 per phase. I have some BlackGate VK 150uF caps. I would end up lowering the total per phase from 600uF to 450uF. What else would need to be changed with this decrease. If the BlackGates have lower ESR, would I even need to change anything.
I thought you said in your original post above that your amps had 28,000uF of capacitance, or are you now referring to the HV supply? Either way, I have never been convinced that Black Gate electrolytics were particularly magical, and I don't think the ESR of a BG would be any lower than that of a top line Panasonic (TS series) or Nichicon. Bypass film caps will give more bang for the considerable bucks of a BG (but I guess you already own the VKs). On the HV supply, I use pi filters. Start with around 50uF then use a low DCR inductor (I use Hammond 3H) followed by 100uF or 220uF.
Lew
You and I listen to highly revealing and highly accurate speakers and we hear a lot of things for what they actually are.That is probably one of the major drawbacks with our ESL speakers and that is,bad material and electronics is put on display in a big way so when I tell people that black gates are nothing special,they can't understand why until I put a film cap or motor run in its place.
Honest amplification is better than excessive 2nd order distortion anytime.
We tried them as coupling caps in a solid state mixer and they worked great.
But when we installed them in the power supplies of an amplifier they really were nothing special. The Illinois part worked just as well.
Maybe my terminology is incorrect. See you in the morning. Bill
So, I had some Clarity ESA caps lying around, 0.82uF, 630V. 1)this is a nicer sounding cap than the one I removed, and it showed by being a little smoother, but 2)going lower inserted some artifacts into the sound.
Time to insert some higher value bypass (ripple current) caps.
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