3886 Ebay kit Build

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It will be an Antek toroid. I have another identical kit coming from China and should be here around the 4th of March. I wasn't sure if I needed to use both filter/rectifier boards or not. I thought I was going to be able to bridge one set of chips for a sub woofer but, after some research and suggestions from fellow diy's.....that's not going to work. I was also pondering running two amp boards in parallel for the left and the other two in parallel for the right.

I've been trying to get all the right parts and now I'm down to the proper transformer to run both of these kits. I've narrowed it down to either a 300va or a 400va trans with 25v or 24V secondaries.
 
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I used the filter board with original components. My amp gives a fat pop about 3-5sec when turned off. But I will live with it, don't like the idea to have some relays on the output.
The idea for the enclosure was ok, but my metalworking skills are rather modest - next one will be better. It is only around 2.2" high, otherwise it would not have gone into my tv stand (clearance above filter caps only 0.2").

I'm using a 150VA 2*19V 2*3.94A toroidal for it. I first bought a 300VA 2*30V, but this gave +/-50V after rectification and filtering, the filter board hummed loud on it's limits.
It is expensive to be stupid :)
 
AndrewT you are right!
I checked in my electronics closet, that copper donut is 2*35V indeed.
I bought the thing before I learned that after rectification increases voltage. Now I need to wait until some project comes by that can use the higher voltage.
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So does anyone know what the 12v output is operating back in post #88?

Going back to post #88, and the referenced webpage, the 12v DC is used internally for each of the four input relays. I can only guess the traces on the PCB provide the connection to the relays (traces are not visible).

The 12v DC also appears as a "pin out" on one of the PCB connectors. I suspect it is there for convenience, if the DIY'er wants to use it. No need to use it as part of the switching circuits. (I.e., consider it optional).
 
Can those Wima input capacitors be replaced by Audiophiler MKP 4.7uf 400V like the one shown on the picture attached to this?

Sure! if the input caps are on boards and the "upgrade" input caps are too big to fit on boards.. just remove them and use jumpers instead and just put the big caps at the RCA inputs!. Check mine!
 

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So is it good practice to have a 4.7uf axial cap at each input. I'm looking at 4 inputs. so 8 caps total? If so then I have 12 of them in a drawer somewhere.
Yes, Better safe than sorry! they are there to eliminate DC do not get into your amp.if you have the space for these big caps, just put one on each board, but if you do dot have space than you can put one in each input RCA before the input selector and potentiometer. if you have them...USE THEM ;)
Remember to take the wima caps out and put jumpers there.
 
Can't put pictures up right now (camera acting up) all I can do is work off my renderings right now. I'll get one up as soon as I implement the new parts into the design.

Another thing...Is it easier to build an amp around your loudspeaker setup or the other way around? Don't know why this just now lit the bulb in my head:rolleyes:
 
Can't put pictures up right now (camera acting up) all I can do is work off my renderings right now. I'll get one up as soon as I implement the new parts into the design.

Another thing...Is it easier to build an amp around your loudspeaker setup or the other way around? Don't know why this just now lit the bulb in my head:rolleyes:

I would build an amp "friendly" to 4ohm and 8ohm loads. That way you can use it with almost "all" speakers known.;)
 
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