DIY Craplifier Project

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Thanks Mark.

I was thinking of a two box affair with umbilical, to avoid the ScheissenMaster leaving its odor and bad juju within the chassis.

Having its own chassis also provides accommodations for front panel fine-tuning of the ScheissenAdjust(tm) modules.
 
How about an adjustable damping factor? I think I've seen it done before. Nothing like being able to adjust your bass from "jackhammer" to "extra-flabby".

Actually, you could even dispense with the "jackhammer" altogether (we can't set our sights too high now, can we?)...



Yes I’d also be quite interested in hearing various profiles or 2nd and 3rd order harmonics.

I’d like to stay away from contentious areas like the use of feedback, and stick with things that have been verified as audible in blind listening tests.
 
I have an idea.

Get yourself an adjustable high current power supply and start with a single FET. You may coin this endeavor... "the sound of one FET clapping".

Then decide that it can be improved. You will start with a constant current source for this FET, and post your results.

Afterward, you'll explode different schema, current sources, and loads.

And you'll post these results. We might chime in, or build it ourselves.

Upon conclusion of these events, we will jokingly refer to you as "papa".

Zen articles series Bis...
 
Too late, it is already done! You don't need to build a craplifier; you only need to visit my only thread. But be careful to use the worst of speakers you can find, as the craplifier can instead of an audio signal, send a DC current, effectively converting your speakers into expensive heaters. I didn't try my latest circuit edition, but I do not expect seeing the complexity of other amplifiers.

To get a craplifier all you need, is to assume every stage is ideal: so, we have an ideal differential pair, ideal current sources, and finally, an ideal pre-driver stage. Also remove any emitter resistors from the output stage and you get thermal runaway. You can enhance your craplifier by assuming your power supply has no mains ripple, there are no parasitic leaks to earth, and above all, that parasitic capacitances and inductances do not exist.

Well, the hard part for me is making a properly behaved amplifier with an acceptable output rather than making a craplifier. The latter, doesn't need much effort to make.
 
Build it with a single ended power supply (e.g. +70V and GND) and couple the loudspeaker to the output stage with a high valued electrolytic capacitor {chosen for adequate ripple current rating of course}. This gives two benefits:

1. No DC offset voltage across the speaker. Ever.

2. ENORMOUS turn on and, most craptastic, turn-off thump.


The first "separates" system I ever bought, included a Spectro Acoustics stereo power amp with Quasi Complementary output stage and GIGANTIC turn-off thump. Yes, Nelson, I ran it into brand new ESS AMT-1 loudspeakers. Good times.
 
If you've got access to individual potentiometer sections, stackable upon the same shaft:

why not build a 14-way potentiometer (7 sections for the left channel, 7 sections for the right channel) which continuously mixes X% of GoodCircuit with (100-X)% of BadCircuit, for each of the 7 circuits in member jcx's link? Rotate the pot shaft all the way left and you get 100% GoodCircuit. Rotate the pot shaft all the way right and you get 100% BadCircuit. In between you get the thing that Nelson Pass tried and failed to achieve, according to post #27.
 
Roflcopter!!!!!!

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Except for the 5 easy pieces is a way to get increased performance and quality out of the chipamps.

Try the LM3886, it's really quite good. If we get around to making a gainclone/chipamp for the store, it's going to be a 3886 with one of the 5 easy pieces implemented. 😀
 
You will all have a different opinions of what's good or bad.

Somebody's feeling will get hurt.


Is it too late to suggest a quantum switch? Preferably with Amphenol kryptonite plated quantum-quick-connect(tm) terminals in which one could connect a lego, a hearing aid battery, a $50 resistor of any value and/or a live cat.

My solution to the curmudgeon-fest is to just imagine all of the banter as a conversation between Bob Widlar / Bob Pease and the Sith Lord (I mix it up for a change of pace..... Pease is a bit nasally to listen to in your imagination for too long).

Has really revolutionized my diyaudio experience. 5 Stars, highly recommend.


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