Pictures of your diy Pass amplifier

One more Aleph J playing sweet music:) Couldn´t believe that so few watt could handle my 87db 4ohm so well!!
 

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Thank´s

Used a mini coax for internal signal when building and testing the amp with my test bench speakers. This sounds very good but the mini coax was so fragile so for some reason i changed to shielded mic cable for the signal internal cable before i tried the Aleph with my Dynaudios.
This didn´t work at all! The sound from my test speakers sounds so much better?? To much laidback sound! Dissapointed with the result and my 2 W4S was a lot better with more resolutions and actually better of everything.

Went out again and tore out that mic cable in frustration and solder in a nice old RG59 that i have in other builds!:bigeyes: How can 15cm different cable do so much!!!

The airy nice resolution is back with much better mid bass! This is so much better now and can´t believe how 13watt @ 4 ohm can do bass at same level that my W4S sx1000 mono´s that have a uge amount of power!

Have only listen a few hours with my ordinary speaker setup but the Aleph J have maybe at least 100h with test speakers and for now i can´t decide and need more time to compare! All i can say is that the Aleph J plays like it have way more power!! And i´m not eager to switch back:)

A few different angles from the pcb´s!
 

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Very nice, do you have pictures of the finished inside?
Good you used the 40cm Chassis with 4 heat sinks, the Aleph J is producing a lot of heat :)

Thank's Walter! Yes i decide early to use the 40cm chassis if later try another build that need more cooling. But i now know that nothing else going to take over this chassi!:) Have measured around 58 celcius from each mosfets after an hour playing. Have 405mv bias on both channels.

More pictures coming!
 
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Nice build and solution to use deadspace inside! Also use that softstart and also the dc-protector. Had some turn off thumps before installing it.

Thanks. I installed the soft start board, but it does not work well. I get turn on and turn off thumps, turn off being the worst. My speakers are 95 +\- sensitivity, so it all comes out.

I am about to start the Sony VFET amp with Permender's boards. When that's running, I'll take down the Aleph J, redo soft start, add speaker protection board, and probably upgrade the output capacitors (again).
 
Thanks. I installed the soft start board, but it does not work well. I get turn on and turn off thumps, turn off being the worst. My speakers are 95 +\- sensitivity, so it all comes out.

I am about to start the Sony VFET amp with Permender's boards. When that's running, I'll take down the Aleph J, redo soft start, add speaker protection board, and probably upgrade the output capacitors (again).

Even with my 85db test speakers i had turn off thumps! A few times i forgot to pause the music before i power down the amp and my god that noise possible could kill sensitive speakers!! Now i can power down when ever i want without any noise at all:)
 
Damn man, I LOVE the techflex'd wire and color scheme!

What mad you choose blue, the PCB's only come in that color, or was it meant to be like that from the beginning?

Thank´s!

Scratched my head a few nights before i decide what color to use:) There is a few to choose from! Ordered blue,black and white. So my intentions was to use blue all the way but ran out of it.
 
I have a big turn off thump too. (though my woofers can handle it)
Do you say the speaker protection board solves the turn off thump?
Are the relais activated every time you turn off the amplifier?

Very nice inside ! Love the blue colors...

Thank´s again Walter!

Yes i struggle with this a few hours! There is a few ways to connect the dc-protector and i had some problems with this! I tried as you can to power the dc-protector from the amps power supply. But connected like this you only have turn on protection. When power down the caps still power the dc-protector and you still have turn off thumps. So you have to connect the dc-protector before the power supply! In my case this was impossible with my transformer. Maybe those using transformers with centre tap can connect it without problems?

So i got help from the forum! The advise was to use a separate transformer and ordered a small toroid transformer only for the protector. It turned out to be real crap and very noisy! so i bought an small EI transformer instead that i rebuild and this one is dead silent now:)

So now when power down the amp the dc relays opens up before my finger leaves the power switch:) and the turn off thumps are gone!
 
Another ACA

Here are some images of my new ACA for the office. I learned that cheap SM power supplies from ebay are best left on the 'bay. I got one for $7 that physically vibrated and emitted an audible buzz under the load of the amp that came out of the speakers and bled noise back into the house AC system. Replacing it with an actual Dell power supply made all of the noise go away.

On to the pictures...
 

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