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Old 2nd December 2006, 12:43 AM   #11
zox2003 is offline zox2003  United States
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I ordered mine yesterday and they were shipped yesterday too.I received them today.

Zox
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Old 2nd December 2006, 12:52 AM   #12
ReidK is offline ReidK  United States
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Did you order from onsemi.com, or some other way?

I'm obviously not in a big hurry (I can't use them yet anyway), or I'd have bought them from Mouser or Digikey. I'm just puzzled, since the people at onsemi told me this delay was normal. Oh well, beggars can't be whiners.

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Old 2nd December 2006, 08:46 AM   #13
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My situation was even more wried, I received some MJL4281A but never see the MJL4302A. All I got is a order cancellation notice and I tried to reach them but never got any answer. It had been more than 3months already.
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Old 2nd December 2006, 09:01 AM   #14
AndrewT is offline AndrewT  Scotland
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Hi Zox,
Quote:
Am I will be able to get 150W on 4 ohms with 4 of these devices(+/-42V).
nearly.

1pair will drive 8ohm to about 75W @ 60degree phase angle.

2pair will drive 4ohm to about 140W @ 60degree phase angle.

+-42Vdc is your limiting factor for maximum peak output voltage.

These predictions were checked for continuous operation below 60degC. Music type duty at home would demand much less from the amp (Tc=60degC allows a heatsink of about 50degC which is pretty hot) will not trouble either arrangement.

You will need a stiff power supply that holds up well under load to produce these powers. I suggest 500VA and 4 by 30mF for a stereo amplifier.
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Old 2nd December 2006, 08:50 PM   #15
zox2003 is offline zox2003  United States
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Anu amplifier schematic recommendation's with these devices?
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Old 3rd December 2006, 01:19 AM   #16
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Rod Elliotts P3A
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Old 3rd December 2006, 01:30 AM   #17
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You might be able to derive a decent schematic from this Wiki kit: http://www.diyaudio.com/wiki/index.p...+the+group+buy ... or ... http://home.ca.inter.net/~lloyd.maclean/Krell/Krell.htm

The diagram above (Rod Elliot's @ http://sound.westhost.com/p3a-f1.gif ) is great ... except that you will have to find suitable complimentary pairs for the first stage of the Darlington out put ...

....
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Old 3rd December 2006, 05:31 AM   #18
Bob03 is offline Bob03  Canada
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Thumbs up Try this 1

This amp is fantastic!
Attached Files
File Type: pdf studio amp.pdf (34.6 KB, 696 views)
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Old 3rd December 2006, 07:10 AM   #19
Tim__x is offline Tim__x  Canada
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Though I'm impressed that he pulled off the CF triplet, that amp has some basic design flaws. Some which save a few cents (shared CCS reference), some which are just plain stupid (the fixed LTP collector resistor).

As I recall, we discussed this designer's work in the past and someone said he designs for "sound" (including intentional distortion), so these may not be mistakes.

I don't think I've ever seen a bias circuit quite like it.
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Old 3rd December 2006, 08:45 AM   #20
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Tim_X,
Who's amp are you referring to?
(Wouldn't hurt to be more specific)
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