Thanks @Berlusconi . I will take a photo over the weekend when i get the heatsink. The fins alone is 10cm long on the heatsink. It was cut off a massive piece of heatsink so i think it's going to look really nice and work really nice. i just need to send it in for machine work to prep the mount area for the board.
Here is some info on the toroidal:
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Hi Gerlach,
We have the same approach: DIY is worth doing only if you want to have something much better than ordinarry commercial products can offer. Every single piece must be extraordinary.
My fins are "just" 40mm long, but heat sinks can still cope with the heat. On Krell KSA-50 I had to use fan to achieve high quiescent currents
And your transformer has everything you need.
Just ask if you need help. And don't hurry, it is so easy to make mistakes.
Regards
Totally true @Berlusconi. I Love DIY stuff. I actually got some DIY build stuff between my audio collection, one is this set of Wilson Audio Sasha clone speakers that I have build my self and finished of a few weeks ago. I'm not sure if I'm allowed to to post links on the forum but you will find the build on google. Just search for: Wilson Audio Sasha Clone Build. I will spot a set speakers at the back with Seas Drivers, that is DIY set to. I got a DIY dac to and a Leach amp and Musical Fidelity F15 that i mode with L20 boards. Longs story short, the previous owner send it of for mod work a few years ago and the guys just jacked it and change allot of stuff. But is for other day story.
Back to the A60+. Thanks for confirming on the transformer info. I will keep you posted and ask questions when they pop up
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The schematic in post two is what the seller has presented and we all know how accurate are chinese published data. There is a better schematic published somewhere in this thread. several pages back. And I did not change C5 because square wave is perfect from practically DC to 50 KHz.
PS: When I tried square vave below 5 Hz speaker protection has detected that as DC and has decouped speakers, but at very low frequencies, the square remains a perfect square.
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If you don't reduce the value of C5 two under 100p it will dampen then incoming square wave rounding off the edges so you will not be seeing the true response of the amplifier. The output also needs to be measured pre inductor to once again ensure that you as measuring the true square wave response of the amplifier.
Its also best to use a pulse instead of a square wave from your signal generator with the rise time approximately equal to the maximum slew rate of the amplifier. There is no point feeding the amplifier with a slew rate faster than it can reproduce. Only then can you assess your amplifiers stability.
Thanks @Berlusconi I'm aiming in the same direction with this amp. Got someone locally that can laser cut a casing for me, but i want to design it with the heatsink inside the casing with ventilation opening top and bottom. Will see what sort of design i can copy.
Thanks @stuartmp
I will do what you have just said and I do indeed appreciate your advice. There are so many things to learn how to judge the real value of our products. Right now I am working hard to improve my distortion measurements and have started to use Akitika 2ppm sine generator.
Thanks @stuartmp
I really did enjoy the video and subscribed.
Great, serious approach to the subject, exactly how I envisage DIY Audio.
Picked up the heatsink over the weekend. Need to clean it nicely and cut it and take for milling machine work. Will cut it in 4 pieces and use 2 pieces per side with the fins vertical.
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Thanks. The combination size of the heat sing will be 400mm long x 175mm high and fin size with mounting thickness 100mm. The soft start controllers that I order comes with a temp safety shutdown. I will check how the operating temp is when the amp is up and running and will make a call if I need to add fans.
Sorry, I don't understand the wiring diagram very well - will the ribs be horizontal or will it be 2 sections of 200mm but the ribs are vertical?
I would count on a temperature of no more than 40 degrees Celsius, while the temperature of the crystal will be any higher.
it will be like you mention it here. I will be cutting the heatsink in 4 pieces. 2 pieces will be then connected on each to make one long heat sink about 400mm long then with the ribs vertical then.
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Great Gerlach,
Such a massive heat sink can keep the amplifier cool even at much higher quiescent currents and produce even more clean, undistorted power. And, for me, large heat sinks look cool indicating the reasoning 'because I can'. With 'just' 0.31 K/W I can extract 20W of pure sound, which is much more than enough with highly sensitive 97dB speakers. At loud passages it really doesn't matter if the amplifier goes into AB.
A question: If I understand you correctly, you have purchased the version with output devices and power supply capacitors?
Thanks @Berlusconi . Yes, i picked the one with Elna caps. Here is the link if you want to check ZAR 869.25 12%OFF | Accuphase A60 Current Feedback 8 Parallel Power Amplifier Board Kit Two-channel HIFI Power Amplifier Board https://a.aliexpress.com/_EQURHwR
I'm waiting for the tracking because i paid for shipping, bought it on the 25/09/2022. The Chinese is in a 7 dae Holliday now from the 01/10/2022. I'm on this seller case because all my other stuff that i order for the amp from other sellers is already on there way to South Africa. So lets see if the seller will send me the tracking on the 8th.
Patience, dear Gerlach, patience. Meanwhile you have lots of things to do. Assemble the chasis first.