Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Solid State Talk all about solid state amplification.

Krell KSA 50 pcb
Krell KSA 50 pcb
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 11th February 2019, 11:56 AM   #9031
Dave murrey is offline Dave murrey  England
diyAudio Member
Join Date: Apr 2014
Location: Ongar uk
Originally Posted by OhSoJoe View Post
Awhile back I received these populated KSA-50 clone boards from a friend of a friend who was moving and had repurposed the power supply. Supposedly they work just fine. This will be my second class-A build, the first was a 10W JLH, so this is a pretty big step up and I壇 appreciate any input on my proposed clone.

Click the image to open in full size.

Power supply
Keeping it standard. 2 x 400 VA with dual 24V secondaries (probably AnTek) and 2 x 51,000 uf Kemet capacitors per channel. Anyone know these Kemet caps, any thoughts?

Heat management
I壇 like to use two of the heatsinks below fin to fin and bracketed together on the top and bottom to create a heatsink tunnel. I値l pull the air out the back of the chassis with an 80mm noctura fan mounted to the outside. I値l need a few angle brackets to hold the heatsink tunnel horizontal and I値l use rubber washers to reduce vibration noise. The fan comes with a gasket and I値l cut an appropriate gasket for the heatsink on the inside. To power the fan, I値l use a separate small 12V transformer and a variable power supply (LM317). This should allow me to dial in the fan speed or control it with a thermistor. I can use that same transformer with a thermal switch to rig up a thermal shutoff as well, like a trigger switch.

Click the image to open in full size.

In order for audio gear to leave my home office space it must fit into one of two 7 by 21 cubbies in media consoles (open on the back) and leave enough space for a small preamp and phono stage of some sort. I値l look around, but I知 prepared to build my own chassis at about 12 wide, 12 deep and 6 tall. I値l follow the lead of grimberg. Between the chassis and heatsink there will be lots of drilling and tapping

Soft start
Plenty of cheap prebuilt options on ebay or if the quality of parts is a concern, I値l use the diy audio softstart v3 board.

Click the image to open in full size.

Hi Joe I have got these kemet 51,000 uf capacitors and was told they will be fine.
I purchased my soft start boards from ebay item number 263727499334 High power 40A for class A amp.
Nothing is connected or tested yet as its a ongoing project.
  Reply With Quote


Krell KSA 50 pcbHide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

New To Site? Need Help?

All times are GMT. The time now is 10:14 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio