Krell Introduces new iBias Class A Amplifier Line Preview

AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
Foods and alcohol beverages go hand-hand with amps, don't they? :D

I can't tell the difference between whiskey either. :D
 
RichB

RichB

Audioholic Field Marshall
I can't tell the difference between whiskey either. :D
You sir have gone too far. :p :)

Whiskey's operating in the 80 to 85 proof range all taste the same at some point, but consciousness is lost soon after. :)

- Rich
 
slipperybidness

slipperybidness

Audioholic Warlord
You sir have gone too far. :p :)

Whiskey's operating in the 80 to 85 proof range all taste the same at some point, but consciousness is lost soon after. :)

- Rich
Even if you can't tell the difference between good and cheap whiskey while drinking it, you can certainly tell the difference the next morning!
 
ImcLoud

ImcLoud

Audioholic Ninja
Foods and alcohol beverages go hand-hand with amps, don't they? :D

I can't tell the difference between whiskey either. :D
WHAT? bite your tongue....

I have over a dozen different whiskies in my bar and they all are different, there is a noticeable difference between whiskies of the same brand and bottle sometimes {meaning a bottle of knob creek may taste different than another bottle}....

I am going to have to reconsider the validity of every statement you have ever made after reading that post. I am starting to think you have handled to much sodium pentothal to be taken serious anymore....
:D lol, if you really seriously can not tell the difference in whiskeys, you are drinking the wrong stuff, go and get yourself a bottle of Jameson Black reserve and compare it to anything else from $50 a bottle down and you will see the difference, if your mouth can not see it, you will the next morning in the least...

Women, Speakers, Whiskey, guns, and motorcycles, the stuff little boys become men for...
 
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I

ILO

Audiophyte
In late 80s I came across the article about Quad 405 in Wireless World (it was a British electronics magazine). I liked the idea so much that I decided to design and build own version of forward feed design following Quad 405 architecture. I had a crappy AB class amp - totally non-complimentary design with pretty cheap components. I essentially threw away everything except of power supply and output bipolars which looked exactly like on this picture. Then I designed forward feed amp with minimal amount of components going for simplicity. Did not try match beta or anything. If I remember I used 1% resistors and avoided caps. I do not remember all the details but I made driver complementary A-class and kept output stage non-complementary B-class, i.e. crudest output stage you can imagine. For preamp/input I used op-amp as in original design to keep things simple, it was like 250mv.

The problem with this kind of design was that the idea was based on balanced bridge which included inductor and capacitor. If I recall correctly it was necessary for stability and for forward feed. But it made impossible to balance the bridge for all frequencies. I chose to balance at 1Khz using scope and a passive subtraction circuit (input/output) to amplify distortion. Yes, distortions were eliminated completely at 1 Khz. But it was impossible to eliminate them at all frequencies. It sounded much better than original amp but I did not have high end system so cannot judge how good forward feed idea was but I know that it is far from perfect and would rather design perfect amp differently like no caps and DC servo instead, inductors, fully complimetary balanced, cascode JFETS as input stage and MOSFETS as drivers and output current amplifiers, high precision resistors and so on, as much A class as possible basically how modern high end amps are designed.

I not a native English speaker so I am sorry if my language is far from perfect.
 
A

awdio

Audioholic Intern
How is this bias arrangement different than the one they used in 1994 with their S class amplifiers?
 
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