Pictures of your diy Pass amplifier

pass aleph 30

just finished my aleph 30 today.

first setup:
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back view:
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top view:
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on test:
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this amp is semi finished, full takman carbon film resistors, elna silmic II, and nichicon goldtune 10000mf x 16.
tested with tannoy spk, very clean and good sounding.

a little distortion occur when passive volume set to half,
but i have to put my ear next to the spk to hear it.
still have to tweaks a little about this.

any suggest?

thanks.
 
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raise those sinks up, and you can cool down 2 of those amps.
the way it is now is the worst way you can have them. all the heat is trapped inside the sinks at all time.

too bad, the height of chassis is not fit for 15cm, only 14cm.
that is why i lay them down, but it true the heat was trapped inside.
so i need a modification here.

not enough info

both channels ?

yes, both.
sound like "bees" when the volume set to half, no music.
very little, but however i must eliminate them.
 
Official Court Jester
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too bad, the height of chassis is not fit for 15cm, only 14cm.
that is why i lay them down, but it true the heat was trapped inside.
so i need a modification here.

do you have enough deepness for 3 of them , as I said previously , rotated for 90 ?

....

yes, both.
sound like "bees" when the volume set to half, no music.
very little, but however i must eliminate them.

what sort of volume , with or without the source ?

do you have a scope ?
 
maybe you can get 1cm cut off of th sinks? thats the easy way:)

does the noise change with volume? and have you tryed with differnt sources?

noise doesn't change with the volume.

do you have enough deepness for 3 of them , as I said previously , rotated for 90 ?

what sort of volume , with or without the source ?

do you have a scope ?

3sink rotated need 45cm and my chassis only 40cm. :(
the bees occur with the source, when i disconnect the source it is gone.
i use old pioneer cdplayer.

ZM. i have some doubt that the chassis is 450+mm deep. but is sure is 300+mm deep:)
that will work:) if the boards is not way over 300mm wide:D

yes you are right not enough deep.:confused:
 
My UGS Preamp

I made this for three years. :)
2sk389BL,2sj109BL,ztx450,ztx550,remote contol,acryl-sash
 

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sound like "bees" when the volume set to half, no music.
very little, but however i must eliminate them.

Sounds like transformer buzz. Good grounding will help (ground the "body"/leg of the EI trafo properly) but when the trafo must operate very hard (close to its full capacity) there is nothing you can do to make it buzz-free.

Such looking trafo are common in my area too. They are written with "A" (ampere) capacity. But they performance is much lower than that, and is easily buzzing with class-A constant current draw. But if you're trafo is not hot then it is okay I guess.
 
yes you are right not enough deep.:confused:

A slight improvement without having to cut anything is by turning the heatsink up side down (the pcb will be underneath). This way you give more room at the bottom and also less heat trapped.

The heatsink and the mosfet is capable of handling the heat, but using such L-shaped aluminum you have to make sure that the heat will quickly transferred from the mosfet --> L-profile --> heatsink --> air.

I have never used L-profile for class-A amp! If I have to I will use double L-profiles. Connections between heatsinks must be tight using compound after sanding the heatsink on level surface (I use glass surface). One of my amp is using similar intermediate profile but made of copper, not Al.