I've always wanted to make my own amplifier but I've also been hesitant to do so.
I've not even started the little chip amp project I bought the makings for.
but I find I need a new amplifier for subwoofer duties as the one I have been using just died.
I've gone back to the ESP website and reread the project I was thinking about. Rod Elliots MOSFET high power amp the Project 101.
I have a couple of big toroids here as a starting point.
2 * 500 VA
Hoping to find a mentor locally but that has been hard lately with lockdown etc.
Rod E's page does say they if making the high power version you need really big heat sinks and active cooling. Is it possible tho to have heat sinks that are too large?
I have come into the possession of a large heat sink.
It's 3700grams, multi finned, 270mm tall, 180mm wide and 75mm deep
I think it came from a rooftop solar array originally, the donor never said but he's a solar installer
Adequate?
Too big?
I've not even started the little chip amp project I bought the makings for.
but I find I need a new amplifier for subwoofer duties as the one I have been using just died.
I've gone back to the ESP website and reread the project I was thinking about. Rod Elliots MOSFET high power amp the Project 101.
I have a couple of big toroids here as a starting point.
2 * 500 VA
Hoping to find a mentor locally but that has been hard lately with lockdown etc.
Rod E's page does say they if making the high power version you need really big heat sinks and active cooling. Is it possible tho to have heat sinks that are too large?
I have come into the possession of a large heat sink.
It's 3700grams, multi finned, 270mm tall, 180mm wide and 75mm deep
I think it came from a rooftop solar array originally, the donor never said but he's a solar installer
Adequate?
Too big?
For a medium high power amp, it sounds about right for one channel.
Maybe more with a fan. Can you get another one?
Maybe more with a fan. Can you get another one?
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That's interesting as it's about 4 times the size and weight of the combined heat sinks in my 300W stereo amp. I thought it might be too big 😀
Heatsink can never be too big. I think you could easily run a 300-500w AB amp on that heatsink. Although you cant expected full power continuously.
What wattage are you looking to get? Rod’s P101 is only 2-pr of Laterals, I would not go over +/-55Vdc which will be about 150w at 8-ohms, and 250w at 4-ohms. Don’t use for 2-ohm load either.
For a sub I would be looking for 3-4pr of outputs, not for more power (although you could push to 60-65Vdc at the limit) but to operate more in its SOA for a 4-ohm load
What wattage are you looking to get? Rod’s P101 is only 2-pr of Laterals, I would not go over +/-55Vdc which will be about 150w at 8-ohms, and 250w at 4-ohms. Don’t use for 2-ohm load either.
For a sub I would be looking for 3-4pr of outputs, not for more power (although you could push to 60-65Vdc at the limit) but to operate more in its SOA for a 4-ohm load
Sounds like I would need something else or turn it into a tunnel in some way because I have a couple of 50-50 500VA toroids to use up.
Was thinking of the high power version of the amp Running stereo subs.
First post is missing the pictures Added to this one
Was thinking of the high power version of the amp Running stereo subs.
First post is missing the pictures Added to this one
Attachments
Search the APEX A40 or SR200, both use 3-pr of BJTs and gerbers files, BOM and schematics are easy to find on this forum.
You also might like the Apex H23 which is a mosfet amp with 4 or 5-pr of outputs.
You have the most expensive parts with Xfrmr and HS, be a shame not to use them.
Where are you located? Maybe someone close by could assist your build by email or phone?
You also might like the Apex H23 which is a mosfet amp with 4 or 5-pr of outputs.
You have the most expensive parts with Xfrmr and HS, be a shame not to use them.
Where are you located? Maybe someone close by could assist your build by email or phone?
Victoria Australia Large regional city
I build speakers, big hungry speakers that sort of demand to be pushed but know nothing about building amplifiers.
I build speakers, big hungry speakers that sort of demand to be pushed but know nothing about building amplifiers.
To start off, maybe try the ljm L15 MOSFET amp on eBay? 3-pr of mosfets (irf240/9240) and I have run that with +/-65Vdc without an issue. It has a low bias (which might be good) but easy to sub in a trimmer pot and you can adjust to your liking and HS capabilities. Just an idea.