A retro 100 watt into 8 ohms bi polar amplifier.
Based loosely on 1980's Maplin disco amp but with only two output transistors.
Uses up to date and easily available transistors.
The heat sink bracket is fun to make but if I use the pcb as drilling template it all comes out spot on.
I have updated this version to next version which has a DC servo.
Based loosely on 1980's Maplin disco amp but with only two output transistors.
Uses up to date and easily available transistors.
The heat sink bracket is fun to make but if I use the pcb as drilling template it all comes out spot on.
I have updated this version to next version which has a DC servo.
An externally hosted image should be here but it was not working when we last tested it.
So I designed this amplifier to be as small as possible, and to have as low a part count as possible, but to not compromise quality. This was November 2017, and the tests were good.
I finally built the whole thing now, and it looks quite nice, I think.
The paint runs are from trying to spray into the recesses, but I guess one learns.
The amplifier is connected to a BT receiver, which is connected to an Apple TV. Very nice setup. Driving a pair of Monitor Audio BX2.
I finally built the whole thing now, and it looks quite nice, I think.
The paint runs are from trying to spray into the recesses, but I guess one learns.
The amplifier is connected to a BT receiver, which is connected to an Apple TV. Very nice setup. Driving a pair of Monitor Audio BX2.
APEX TD1800 clone
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PeeCeeBee V4H
First channel of my PeeCeeBee V4H is in the final stages.
I build an designed the enclosure myself. The top, side, front and back panels are manufactured by Schaeffer. Quite expensive but well made.
Need to start building the second channel now...
First channel of my PeeCeeBee V4H is in the final stages.
I build an designed the enclosure myself. The top, side, front and back panels are manufactured by Schaeffer. Quite expensive but well made.
Need to start building the second channel now...
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The use of Speakons!
Yes! I really hate those banana connectors; they are so prone to shorting output stages...
I don't understand why the hifi world hasn't adopted the Speakon connector.
It is not difficult to implement for those hifi brands. As an example, here's a picture illustrating what I've done to by Focal Electra speakers.
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I agree wholeheartedly! I build all my amps with Speakons - it's so much better.
Ok, so yes, the white amp above has bananas, but that's because it's a re-packaging using parts I had, so it's not entirely a new amp (first build of it was about 10 years ago), I just changed the enclosure and actual amplifiers. All other hardware was from the original (and new PS capacitors).
And I wholeheartedly agree too - in fact I'm retro-fitting Speakon's to my 1980's built MOSFET amp and speakers soon, amp has fiddly spring loaded speaker connectors, speakers are chunky screw terms.
And the great thing is Speakons can be got cheap and aren't compatible with loads of audiophoolery speaker cables, only straightforward chunky wire. Snobs will hate it of course, though some clever companies will make black/gilt Speakon plugs with posh expensive chunky cable that looks fabulous, and right-angle plugs would be a nice variation too - matter of time.
Speakons are the f**king bomb, especially where you have multi-way amplifiers, i.e. active crossovers, and you really don't want to accidentally plug the woofer output into your tweeters. My mains (3-way) use NL8MD-V/NL8FC; they're perfect.
For those who are feeling very cheap and want most of the benefits of Speakons, search for "GX16" on eBay. Readily available in 2-, 4- or 6-pole versions and once soldered up to some trailer wire 🙂 you won't accidentally short anything out or make a wrong connection. You can also get a reverse-gender version (panel-mount side is female) which is good for the amplifier-end of the cable as it does not expose the pins.
For those who are feeling very cheap and want most of the benefits of Speakons, search for "GX16" on eBay. Readily available in 2-, 4- or 6-pole versions and once soldered up to some trailer wire 🙂 you won't accidentally short anything out or make a wrong connection. You can also get a reverse-gender version (panel-mount side is female) which is good for the amplifier-end of the cable as it does not expose the pins.
You can buy Neutrik LRX backshells which convert a straight plug into a right-angle.
There are also generic-brand right-angle Speakon plugs on eBay, at least in 4-pole.
Perhaps a vs vs for speaker connectors is in order.
I prefer safe, one way and one way only, 40A connectors over difficult to find, and expensive if you do, proper binding posts rated at 10A which can have a risk of short circuit or incorrect polarity.