b24
This is my b24 fully differential amplifier - AMB design.
The β24 fully-differential power amplifier
I made my own power supply, slow start and DC speaker protection circuits. I really went to town with total of 6 transformers. 2x300VA Plitrons for output stage, 2x15VA Plitrons for main boards and 2 supporting transformers for st.by and DC protection. The sound is really good with lots of power.
This is my b24 fully differential amplifier - AMB design.
The β24 fully-differential power amplifier
I made my own power supply, slow start and DC speaker protection circuits. I really went to town with total of 6 transformers. 2x300VA Plitrons for output stage, 2x15VA Plitrons for main boards and 2 supporting transformers for st.by and DC protection. The sound is really good with lots of power.
Attachments
Hi,
This is a 5U chassis (almost 223mm tall) by 500mm deep. The heatsinks are rated 0.2 C/W (2 per side joined with the plate) and I also added a 12.7mm thick aluminium plate bolted with 22 screws very tight. Don't worry, there's anough metal in there. Worst case scenario I will turn down the bias a little. I don't mind if I have 50-75 watts in Class A and the rest of it in AB it will still be pretty good. But my tests so far seems to indicate that it will be fine.
Here's the heatsink before anodizing
I will keep you updated.
Do
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This is my b24 fully differential amplifier - AMB design.
The β24 fully-differential power amplifier
I made my own power supply, slow start and DC speaker protection circuits. I really went to town with total of 6 transformers. 2x300VA Plitrons for output stage, 2x15VA Plitrons for main boards and 2 supporting transformers for st.by and DC protection. The sound is really good with lots of power.
Wow! Very nice build!! I made myself a b24 a couple years ago, I believe you also had started and then waited, Am I wrong?
Anyways, excellent build and yes this amplifier is excellent! I'm actually modifying mine to also use a softstart and remove the bleeder relay and resistors that was in Ti original build (I followed his build).
Ciao!
Do
I used fans in the past, some extremely silent ones and it did a good job, however, I'll try and do without them in this build.
Thanks
Do
Where did you buy the pus boards and amplifier boards ? Want to share some more info
Hi Zeepup,
It is the ExtremA amplifier. You can find the contact here
ExtremA, a reference class-A DIY amplifier. - Introduction
Unfortunately, the only designer left is Sander Sassen but he does not reply to my emails anymore... Maybe he's on vacation or busy? It was designed by Bruno Putzeys (now at Hypex) and PCB layout, schematics and prototyping by Sander.
You can email him if you want. I also have a friend that bought two sets of boards and 4 transformers and parts like mine and maybe he's willing to sell since he has not yet started his.
Let me know if that interests you.
Thanks
Do
honeybadger build progress...
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
read post #290 in this tread before trying to mail Bruno regarding this amp
http://www.diyaudio.com/forums/solid-state/96853-extrema-class-strikes-back-15.html
yes, Cris, as a matter of fact the boards are ready...post #1700...http://www.diyaudio.com/forums/solid-state/211905-diyab-amp-honey-badger-build-thread-34.html
but i am making a SOA protection board, feel insecure without them...
i had a local tin-smith shop made it for me....costs me around U$100...
My heatsink is much thicker than this. This is not even a 1/4" thick and mine is thicker than a 1/4". The fins are also wavy making them longer than they look.
I did a test with bias to 65W in Class A yesterday and my heatsinks are close to 50 Celcius so I'm guessing I won't be going much higher, maybe 75 Watts in Class A but that's way enough for me needs.
Do
The top of the amplifier was installed and it was running for about an hour which is sufficient to know. The temperature stopped climbing after ~40 minutes. Anyways, the 100 watts is a dream but in reality I will most probably put it at around 40 watts in Class A, it gets too hot in the room. In reality and practically, 25 watts in Class A should be sufficient and the rest in AB.
I have to test my comfort level in the room after setting the bias to be at 40 watts in Class A and if too hot in the room bring it down. It will also save on electricity!
Ciao!
Do