C.E.C AMP3300R (3300 R Amp 3300R Amp3300) and AMP5300R LEF Class A schematic wanted

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CEC (C.E.C) claim by their mostly amplifier models, it's class A (here in Germany even "Pure Class A") The name of circuit topology is "LEF (Load Effect Free). The developer is Mr. Carlos Candeias. Have a look to this URLs: Amp 3300R:
CEC AMP3300R
and Amp 5300R (Amp5300R Amp 5300R Amp5300)
CEC EUROPE WEBSITE
The last model delivers 120W/8 ohms and 135W/4 ohms, as to read in the CEC datasheet
If anybody can posted the schematic of one of both models, I will make an evaluation. I guess, the term "Pure Class A" is concerning the pre-driver stage and driver stage of a push pull complementary CFP resp. Sziklai pair, but I don't know this exactly.
If there really pure Class A by the output power devices, where is a heatsink with the appropriate sizes?
Thank you very much for your posted schematics in advance
 
schematics for this CEC models still needed.
 

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  • CEC LEF AMP3300R INSIDE.JPG
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  • CEC LEF IGM.JPG
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I have the feeling that this diagram is only available through reverse engineering of one of the modules. Not sure if they are potted or glued inside that red plastic.

The attached document, otoh, may well describe Nelson's "Stasis" output stage or any other "current dumping" topologies.

Yes. Read the statements by post #3 and #5 of our great master about
http://www.diyaudio.com/forums/pass-labs/5808-cec-amp71.html
The schematic I need (first to make a cost estimate) for prepare this amp device for connecting of a dual mono outdoor power supply.
 
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From pdf

But in the only one published test with measurement was distortion about 1,5 % near full power, so it seems, something is wrong...

The main influence of sonic character comes not from the distortion value but from the kind of distortion. 1,5% low order components is less critical than lower values of high order/complex components created by class b.

Until now most employers by test reviews don't understand this fact - unfortunately until now there are additional no THD/IM measuring line up exist, that privide results so I know, how an amp sounds without carry out an own listening test.

P.S. by post #10 about
http://www.diyaudio.com/forums/pass-labs/5808-cec-amp71.html#post3435797
there is my circuit describtion according a CEC schematic, which I have receive in the meantime. However I doubt, that it is the so called LEF topology.
Thus I am still looking for CEC's LEF schematics.
 
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The AMP3300R is a class A Amp that features an extremely pure Single-Ended Circuit

I have just read this description under
CEC AMP3300R

I note, that for me the English language is still very difficult, because this language uses many terms with no clear statement.
Particularly the term "single ended" in case of audio amplifiers.
The opposite term is differential amplifier stage (LTP) in case of the input (first) and VAS (second) stage
and push-pull stage in case of the output stage
What means now the term "extremely pure single-ended circuit" in case of this CEC's amplifier model and in general?
And what concerns the term "class A" by this amp model (fact is, that input stage and VAS stage runs at most cases - maybe at all audio amp models - in pure class-A)?
Thank you for advices.
 
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The reliability of this models isn't good, because I know several user's with devices in not working condition.
What about the schematics in the meantime ?
Still confidential ?
BTW - sound cannot actually be good, because the residual distortion of an other model with same basic approach concerning the circuit topology looks relly not good - go to fig. 10 under
B.M.C. Audio Amplifier C1 integrated amplifier Measurements | Stereophile.com
 
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