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Old 28th May 2012, 03:31 PM   #21
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J313/K2013
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Old 28th May 2012, 03:42 PM   #22
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So I guess that means front end unless he is a nut-case like me and uses a stack of them for output stages.
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Old 28th May 2012, 03:44 PM   #23
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Go look see "ugs" of the Xs models
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Old 28th May 2012, 03:48 PM   #24
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Where do I look?
I am not really expecting any surprises, unless it is very much different than the XA amps.
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Old 28th May 2012, 03:52 PM   #25
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Quote:
The Front End


Initially we designed a new front end that could be tweaked to produce arbitrary ratios of low order harmonics, and while this worked fine, after we finished working with the output stage portion of the design we found that it worked better to have the front end simply complement the output stage in a largely neutral manner.
The new front end is not more complex than the previous design. It still uses cascoded matched Toshiba Jfets (NOS from our large cache) for the input devices which drive complementary Mosfets.
However we have increased the heat sinking so that this stage can be biased with 2.5 times more current and brought in higher quality Toshiba Mosfets (also NOS).
This dramatically increases the linearity and bandwidth of the front end, and with the proper adjustment of each part of each stage and balancing degeneration with loading gives us an amplifier front end which by itself has low distortion, a 100 Khz bandwidth and a fairly low output impedance – all without a feedback loop.
Also, the new front end has a 200 Kohm input impedance (balanced) with very small capacitance. Anything will drive it.
Feedback is not essential for this front end, but we have left it with enough open loop gain to allow some feedback around the output stage. This is strictly in service of the sound of the output stage – it already has decent specs.

entire chapter is about FE , and nothing else


in any case , I already wrote more than I wanted
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Last edited by Zen Mod; 28th May 2012 at 03:55 PM.
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Old 28th May 2012, 03:54 PM   #26
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OK
This absolutely proves you are smarter than me, and I am the dumbest person on the planet.
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Old 28th May 2012, 03:56 PM   #27
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No shock there.
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Old 28th May 2012, 03:57 PM   #28
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Thank you Jacco
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Old 28th May 2012, 03:59 PM   #29
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Quote:
Originally Posted by Melon Head View Post
OK
This absolutely proves you are smarter than me, and I am the dumbest person on the planet.
nope

fact that you're contemplating about being dumbest , clearly reveals bitter true :

it's well known that I'm the dumbest , while I'm not even aware of that


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Old 28th May 2012, 04:01 PM   #30
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How are you aware that you are not aware?
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