Quote:
Originally Posted by dsavitsk
I think your calculations are off. First choose your 3db point. 2Hz is a good choice as it is 1/10th of 20Hz and it is conceivable that your speakers reproduce 20Hz. Then run the calculation considering that your amp has an input impedence around 50K, and your dac has an output resistor of 100K in parallel, thus you can consider the impedence seen by the cap to be about 33K.
So, C = 1/(2 * pi * 2 * 33000) which is about 2.4uF. The reason that 4.7uF is common is that it is common to see an input impedence of 10K.
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Ok I supose I managed to ignore the output resistor a little too much
And while I see the C = 1/(4pi * f) formula I don't understand why it is correct, Tnagent also uses this formula f = 1/(2pi * RC) for finding the corner frequency and with those values we get 1/(2pi * 33000 * 0.0000024) = ~2
Hmm ok you win, I must have been tired yesterday and had a zero too much in there somewhere.
Quote:
Originally Posted by dsavitsk
A fool and his money. I think you are expecting magic from these caps that just doesn't exist. They do not make a circuit better, they simply do less damage than other caps.
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And the difference between improving and doing less damage is...?
I am not
that far gone, I do understand that they will not turn my dac into a television set
I admit I have absolutely no idea what they will actually do and how great a difference they will actually make. But I do understand this: Education may be free in my country but learning never is - the only way I will ever learn what caps do and do not do is by spending the money and trying some different ones out.
Quote:
Originally Posted by dsavitsk
Also, if you just got this working in the last couple of days your existing caps (not to mention the transformers, chips, and PS caps) are not broken in yet and will continue to change in sound for at least a few days if not longer.
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I realize that, and I will wait patiently before actually changing anything around, but I sincerely doubt that I will not be able to tell the difference between a pair of 2 cent electrolytes and some quality caps - I could be wrong of course - never happened to me before but there is a firs time for everything
Quote:
Originally Posted by dsavitsk
Also, keep in mind that a lot of these caps sound better, or at least different with a high voltage applied to them. They may not sound their best with the 3.85V from the dddac.
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There seems to be a lot of controversy on that subject, and without a higher voltage output to compare with there is little chance of me actually determining whether or not I think it is true.
On and end note when I ordered the kit from Doede I was hoping it might be better than my E-MU 1212m, I was not expecting anything major and certainly not a revelation - but when I had finished it and listened for the first time my jaw dropped I felt like I was experiencing hi-fi for the first time all over again - I am very very impressed with this DAC.
But of course as all things go when I got over my initial bafflement I started to notice the ups and downs, amongst other things I find it a little lacking in bass punch and I am not a basshead at all - it is very tight but just a little too weak I figure a better PSU and some more burn in time will take care of this.
I think it can be tweaked to go where I want it to be, the flaws (if you can call them that) are all minor things that could be just a little bit better.
And my reason for ordering more than one set of caps at once is that not living in the states and the states seeming to be the only place where things like this are actually sold (which I supose should worry me) the shipping costs are not trivial nor are the shipping times.
That coupled with the fact that I intend to actually try and learn something makes it sensible to order 2 or 3 sets.