Haha!! No that is my couson that last year helped me with the woodwork that went into building the set of PA cabs he's laying on!
Exicons aren't that bad when bought from Profusion PLC, I bought a few last year and the price was fairly good (they are also excellent for caps).
In reference to the schematic posted by Matth, given that this is for a subwoofer -- the implications opf the values of C1 and C3 need to be carefully considered. Something of the same applies to the ESP P101 as well.
thx guys
but somehow there is no solution yet.
sam...what do you mean, that they have to be considered? mustn't it be uncritical to run them under their usual voltage?
so what design is to be considered if i want it easy(to build and to get components) but good enough for my needs?
greez
but somehow there is no solution yet.
sam...what do you mean, that they have to be considered? mustn't it be uncritical to run them under their usual voltage?
so what design is to be considered if i want it easy(to build and to get components) but good enough for my needs?
greez
C1 at 1uF is a high pass filter with Fc (point of -3dB attenuation) at about 150Hz. at 20Hz the attenuation is about -18dB. This may well have been a desirable trait in pre-digital days where "wow", "flutter" and "rumble" caused by turntables and tape decks were serious issues. Putting that much low frequency at the input to a subwoofer amp seems counter productive. 10uF is much more reasonable while keeping the size of the C1 from being to large.
I've seen commercial "plate amps" made foe powered subs that use 470uF at that position.
That's just frequency response. An additional concern is the noise floor which C1 and C3 dominate all the way up in to upper bass lower mid-range.. Both C1 and C3 are sources for this. Usiing a film cap helps in the case of C1, but physical size prevents that solution for C3. A simpler, "blunt instrument", approach is to increase the value of both. I've been using a bi-polar electro of @47uF at C1 (or a pair of opossed 47uF tantalums). At C3 iv'e started using 1000uF.
Voltage ratings for C1 don't mater much but C3 can experience full rail voltage so that must be dealt with.
My opinions in this ara are based on A- Spice simulation, B- actual measurements I've personally conducted, C- personal listening and D- opinions of certain others who have something of a reputation in the field. All four agree which encourages me that this is real and not just one of my audiophile fantasies.
okok .... i've already figured out that there are very competitive people around this forum who are experienced. as i'm not a nerd in electronics but new to diy-amps i thought diyaudio would be a good point to ask and to get good answers like yours...and the others. hope i've your last lines understood correctly.
you say C1 is a high pass ... as far as i understand it's a kind of subsonic filter then, isn't it?
by the way ... i will also build an active crossover or filter for the sub and if needed also a preamp.
so if you've tried 1000µF @ C3 isn't it a rated a lot too small in matts schematic?
what about considering esp's p68 and running it at 56/55 V?
greez
you say C1 is a high pass ... as far as i understand it's a kind of subsonic filter then, isn't it?
by the way ... i will also build an active crossover or filter for the sub and if needed also a preamp.
so if you've tried 1000µF @ C3 isn't it a rated a lot too small in matts schematic?
what about considering esp's p68 and running it at 56/55 V?
greez
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