Bob Cordell's Super Gain Clone PCB (LM3886) and a stripped-down version: Compact3886

Thanks for the replies so far. If you haven't guessed I am still very new to the hobby. I was really asking what the difference is in the fundamental design of the amplifiers. After doing some more research and asking a colleague, it seems like the fundamental difference is that the gainclone is digital and the Amp Camp is analog. Both are solid state. Is that a correct assumption?
 
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bobberner, your colleague got one thing right: neither the Cordell Super Gainclone, nor the Amp Camp Amp, includes vacuum tubes. Not a single tube in either one.

The heart of the Amp Camp Amp is component #1

whereas

The heart of the Cordell Super Gainclone is component #2

Why don't you forward those links to your colleague, and ask her/him to look them over? Maybe a light bulb of sudden understanding will illuminate... ? You might find it easier to trust the opinion of a colleague rather than a bunch of relative strangers on a website.

_
 
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Readers,

Member bobberner PM'd me on March 13th to ask whether this set of PCBs might make a good project for a class he teaches at a community college in the Eastern time zone of the US. Then he asked for roughly comparable amps available in kit form (letting someone else do the miserable grunt work of sourcing components). I replied by PM

Bob, the closest comparable kit is the (very excellent) Akitika GT102. For $314 you get two amp channel PCBs, one PSU PCB, two heatsinks, a pre-drilled chassis, all electronic parts, a power cord, a lighted ON/OFF switch on the front panel, and no requirement to spend hours and hours of your time ordering individual components from Mouser. Or finding substitutes for out-of-stock parts.

GT-102 Stereo Power Amplifier .

Now that ACA is available in kit form it might, or might not, be considered a "comparable" amplifier.

-- Mark Johnson (thread starter)
 
How about these?

Weird, you can't use google?


For some theory:


Taming the LM3886 Chip Amplifier – Neurochrome


A Complete Guide to Design and Build a Hi-Fi LM3886 Amplifier - Circuit Basics


High quality PCBs:


LM3886 Done Right: Best DIY implementation of the LM3886 80W gainclone – Neurochrome


LM3886 Amplifier -
EasyEDA



There are others. Just search the forum.


Lower Cost Alternatives:


Any of the LM3886 amp kits on Alibaba will be to be more than adequate. Could be a good exercise for the students to verify the kit contents before they start construction.


You could even get different groups to try separate kits and then report back on their experiences.
 
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I had similar misconceptions about the differences between ACA and gain-clones (aka _chip_-amps). A chip is usually connotated as being a digital device...
Well.
For the sake of the art, I wouldn’t recommend any cheapo out-of-anywhere gainclones, but try to stick to valuable designs from the hands of respected masters, like Nelson Pass or Mark Johnson.
Thus, you can be confident the concepts are thought through and are free of flaws...

The documents referred above are state of the art, too. They require a lot of attention!
 
Mark wrote"

"Bob is the inventor of the Super Gain Clone, read what he has to say about it. You'll discover that Bob recommends a second Zobel network (33nF series 10R), after the output inductor. These components are not present on my PCB layout; if you decide to install them, one good option is to solder them directly across the loudspeaker output terminals."

Are builders adding this 2nd Zobel?
I did but I wondered what others are doing.
stay safe
t
 

PRR

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...misconceptions... A chip is usually connotated as being a digital device.....

???

And a horse is a recreational animal, can not do Real Work.

Don't tell the horses I saw around the corner last week....

The first proposed "chip" was analog. The Big Money in early chips was (military) digital, because BIG systems need Reliability and digital is prone to big systems, but as soon as that market got full there were analog chips.
 

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I finally started assembling the power supply for the gainclone today. A fellow instructor at the college is teaching me how to solder and helped me get started on the PS. He was very impressed with the quality of the PCB and how all the parts were labeled in the bags from Mouser.

So a big thanks to Mark for putting this together and doing such a nice job of it! I just need to save my pennies for an enclosure now. Any suggestions for an inexpensive alternative to the Dissapante 2U? At least for an initial enclosure. I'm assuming it's the heat sinks that are the expensive part.
 
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Hi,

Has anyone produced a super gainclone circuit I could etch at home? I haven't made anything for a while, but have most of the components already.

Thanks

Richard

Lightyears after your post but here is the one I made without the KK. I tried one with the KK but couldn't justify it sound-wise and decided to leave it out as per Bob's design option. See post #89.

Super Gainclone With Klever Klipper Based on Cordell Design

Note should you decide to accept this mission: Double check trace clearance when etching. Also, clearances are tight near the LM, so really clean the board after soldering if using flux as this can affect the amp if not completely cleaned off (I found that out by accidental experiment:D)