Spent 2020 lockdown doing a prototype version of an LM3886 amp. Bit of a progress between the first photo and the latest.
And now use this amp every day (still need to get better front-panel for it).
And now use this amp every day (still need to get better front-panel for it).
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maybe add a valve on the top for the real deal? Perhaps a simple cathode follower buffer at input.
My current project: Plate amplifier for my living room sub. It will be able to run in a 2.1 configuration. The TDA7293s on the board are in a 2xParallel configuration, allowing me to have speakers with low impedance as my tops. The Amp for the woofer will be a IRS2092 based module, that is not part of this PCB.
On top, I've added DC protection using a µPC1237 and a ADAU1701 as a DSP. For input either unbalanced or balanced analogue audio is supported. If required, I can use TOSLINK or S/PDIF as input as well, translated via a WM8804 that transforms it into I²S.
On top, I've added DC protection using a µPC1237 and a ADAU1701 as a DSP. For input either unbalanced or balanced analogue audio is supported. If required, I can use TOSLINK or S/PDIF as input as well, translated via a WM8804 that transforms it into I²S.
G'day Guys,
May I present a project I've been brewing for a while.
A dual mono gainclone using 00940's LM3886 boards.
The rest is all home brew: chassis, cap banks, rectifier boards, speaker protection boards etc.
It's been quite the experiment. Many things I will do differently on the next power amp but this one was designed as a backup amp so mistakes and learnings are ok!
May I present a project I've been brewing for a while.
A dual mono gainclone using 00940's LM3886 boards.
The rest is all home brew: chassis, cap banks, rectifier boards, speaker protection boards etc.
It's been quite the experiment. Many things I will do differently on the next power amp but this one was designed as a backup amp so mistakes and learnings are ok!
Bottom row: LM3886 Gainclone PCBs. Not minimalist, but minimal. Specifications agree or better than those stated by IC manufacturer.
Top row: 5A fused AC-DC power supplies with individual rectifier diode snubbing. Transformer used, 22-0-22V AC nominal all large capacitors 50V but to be fair, 35V will have been quite adequate.
Top row: 5A fused AC-DC power supplies with individual rectifier diode snubbing. Transformer used, 22-0-22V AC nominal all large capacitors 50V but to be fair, 35V will have been quite adequate.
This China-board with parallel TDA7293 has been driving my sub for the last 2.5-3 years. With +/- 33V I was quite satisfied with the performance at a 12" in 50l cb.
Yes nice, the perfect R-core transformer. Where do you get them from, because I can't find any R-core transformers with 300VA. And I already googled Selectronic.
Hello,
I built this power amplifier 6 years ago and started to completely rework it during the Corona period. That's the current status. I still have to adapt the secondary lines (I don't like wires, I prefer stranded cables) so that the transformers finally find their place. I still need to solder the signal wires and continue assembling the case. Unfortunately, by the front panel is left for the time being, because I don't want to take over the old one and I don't have a new one yet.
I built this power amplifier 6 years ago and started to completely rework it during the Corona period. That's the current status. I still have to adapt the secondary lines (I don't like wires, I prefer stranded cables) so that the transformers finally find their place. I still need to solder the signal wires and continue assembling the case. Unfortunately, by the front panel is left for the time being, because I don't want to take over the old one and I don't have a new one yet.
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Finally! it was a very long journey with my audiosector kit from 10+ yrs ago. I found the hardest part was a home(case) for the amp and PSU. In the end mono blocks with a simple passive matching theamed pre amp. I carried the indicator LED via fiber optic to a small hole 1/16" on the base plate. I didn't want to take away from the beauty of the wood🙂 I have been driving a vintage set of B&W 500 series floor standers, the listening experience is most pleasurable.
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Absolutely stunning, and that is incredible wood!
How does the heat get out?
How does the heat get out?
Used the Audiovector brds myself. Use my chip amp in system #3 around the TV with a SS preamp driving Markaudio speakers. Built mine in a 1U enclosure with two low profile trannies. Love your timber enclosure.
http://retro-thermionic.blogspot.com/2019/07/overture-lm4780-chip-power-amp.html
http://retro-thermionic.blogspot.com/2019/07/overture-lm4780-chip-power-amp.html
