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Chip Amps Amplifiers based on integrated circuits

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Old 21st January 2013, 08:14 PM   #61
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Quote:
Originally Posted by Mooly View Post
I have a question

The circuit in post 1 could be duplicated (i.e. two built) and then be fed from a "normal" source such as a CD player etc. Both circuits would in that case operate independently of course.

Can your "new" circuit like-wise be duplicated in the same way and two the "channels" operate independently when fed from a "common" source.

Just a wonderin
Yes. In my amp I have it working in the same way.
 
Old 21st January 2013, 08:30 PM   #62
kouiky is offline kouiky  United States
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I am almost certain I knew exactly what the Op did, as I've done it in the past. I had put pictures of it up on imageshack and shared with a few friends this past autumn, and it offered a flat phase and response from less than 1Hz to over 100kHz. I'm running some models to try and remember.

Last edited by kouiky; 21st January 2013 at 08:33 PM.
 
Old 21st January 2013, 09:00 PM   #63
magdrop is offline magdrop  United States
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Quote:
Originally Posted by sreten View Post
Hi,

Really ? How do you know that ? You'd have to know the supposed
solution and your stuff to be any judge of the merits of this thread.
I know it because I'm smart. Like a lot of folks here are. And no one has come up with a correct solution yet. Which does support the claim of novelty.


Quote:
I've already posted how you usually would do it, and it works.
No, not true.

If you could actually post a solution to the puzzle then you would be the winner of the challenge, instead of just another loser.


Sure, there may not be any solution, but I think the OP actually does have one. But those who don't like the challenge don't seem to be making that argument anyway. They seem to be arguing that the challenge is just too simple and mundane to bother with, that the solution is beneath them. That's what makes it so damn amusing.
 
Old 21st January 2013, 09:09 PM   #64
kouiky is offline kouiky  United States
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I had put pictures of it up on imageshack, so I'm running some models to try and remember. The values I used were obviously different at that time and thus so was the response & phase, but still better than +/- 0.1dB from 1-100kHz, less than +/- 2 degrees.
Click the image to open in full size.
 
Old 21st January 2013, 09:51 PM   #65
sreten is offline sreten  United Kingdom
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Quote:
Originally Posted by magdrop View Post

I know it because I'm smart. Like a lot of folks here are. And no one
has come up with a correct solution yet. Which does support the claim
of novelty.

No, not true.

If you could actually post a solution to the puzzle then you would be the winner of the challenge, instead of just another loser.

Sure, there may not be any solution, but I think the OP actually does have one. But those who don't like the challenge don't seem to be making that argument anyway. They seem to be arguing that the challenge is just too simple and mundane to bother with, that the solution is beneath them. That's what makes it so damn amusing.
Hi,

Well that is all we need, more self opiniated egotistical pretension.

You know because your smart ?
What an utterly limp argument that suggests the exact opposite.

If your so smart and clever rather than a loser, post the "solution",
rather than whining about attitudes you are presuming to be the case.

Or say something that indicates you understand anything about it.

rgds, sreten.
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Last edited by sreten; 21st January 2013 at 09:54 PM.
 
Old 21st January 2013, 09:52 PM   #66
sidiy is offline sidiy  Canada
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diego,
If it is what I think it is (my turn to be "misterious" ) you'll need to plot inputZ vs. Freq.
Something nasty will turn up...Your signal source will have to drive a dead short past ~10kHz or so...therfore distorsions will raise signifcantly wrt Freq. The classA amps can't save the day here.
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Last edited by sidiy; 21st January 2013 at 10:12 PM.
 
Old 21st January 2013, 10:06 PM   #67
sidiy is offline sidiy  Canada
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Here are my results, first two very similar to those in your initial post.
Attached Images
File Type: jpg FR.jpg (318.0 KB, 151 views)
File Type: jpg Phase.jpg (327.0 KB, 148 views)
File Type: jpg InputZ.jpg (309.5 KB, 142 views)
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Old 21st January 2013, 10:14 PM   #68
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magdrop:

Thanks for joining!.

In my humble opinion I think that there are no losers, while we can salvage something positive from these or other threads.

My greatest respect.




kouiky:

WOW!. I am expectant that may exist more than one solution.

This can be very interesting.

regards



sidiy:

You can upload the schematic?

I'll try to post what you ask, or at least tell you if something like that happens. Give me a little time, please.

regards

Last edited by diegomj1973; 21st January 2013 at 10:25 PM.
 
Old 22nd January 2013, 04:04 AM   #69
sidiy is offline sidiy  Canada
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Quote:
Originally Posted by diegomj1973 View Post
sidiy:

You can upload the schematic?
Of course! With only one modification it satisfies all the conditions and gives the same simulated results. The bad news is that it loads the source pretty badly so in applications for audio one must consider headphone type outputs with care for stability, distorsions...etc.
Attached Images
File Type: jpg OpAmp_challenge.jpg (88.3 KB, 110 views)
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Old 22nd January 2013, 06:34 AM   #70
Mooly is offline Mooly  United Kingdom
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Quote:
Originally Posted by diegomj1973 View Post
Yes. In my amp I have it working in the same way.
Thanks... my reason for asking was this... to confirm that two identical circuits can have either the "negative" or the "positive" of their respective signal sources joined together (as would happen with a CD player with the negatives being common) and that both circuits would still operate correctly

I haven't been able to figure out how to meet all the requirements. The circuit I offered earlier that matched your phase and amplitude plots almost exactly, removed the ground referencing of the input source.
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