i should have specified ANOTHER amplifier, because i suppose you could force the outputs of this amp into class A and perhaps get better numbers. however it seems you would have to buy a DSCOPE or build your own instrumentation to prove it; given this one is bouncing against (or actually under) the distortion of the AP
Ha I have no Idea really... I just come along and listen and read and have a think then scratch my head.
I have an older Krell KSA150 Class A amp which I bought 2nd hand when I got together my first Hifi. I havent really listened to any other amp, having no friends in Hifi and not having a disposable income to have a revolving door attitude to Hifi. I would however like to not have a 60c heater to power my speakers so I am interested in amps that are a little more efficent.
OPC I bought your headphone amp (Wich I have yet put together) and I am very impressed with the simplicity and elegance of the PCB - as I am with this amp. It just looks so nice.
If I knew more (anyone) people into hifi I would have access to listening to different gear but alas I just have my rig. Which is very good anyway.
Krell amp
Classe Pre amp
Duntech Princess speakers
thanks for all the replies.
I have an older Krell KSA150 Class A amp which I bought 2nd hand when I got together my first Hifi. I havent really listened to any other amp, having no friends in Hifi and not having a disposable income to have a revolving door attitude to Hifi. I would however like to not have a 60c heater to power my speakers so I am interested in amps that are a little more efficent.
OPC I bought your headphone amp (Wich I have yet put together) and I am very impressed with the simplicity and elegance of the PCB - as I am with this amp. It just looks so nice.
If I knew more (anyone) people into hifi I would have access to listening to different gear but alas I just have my rig. Which is very good anyway.
Krell amp
Classe Pre amp
Duntech Princess speakers
thanks for all the replies.
Hi Guys,
I'll field a few questions:
null object:
As qusp correctly stated, this is indeed a class AB design. Each buffer draws roughly 13mA at idle but can deliver in excess of 250mA peak. That means the amp is generally in class A operation up to about 200mA output (because there are 8 parallel devices), and then transitions to AB. Keep in mind that the above numbers are approximate as I don't really know exactly how the current is distributed in the buffer. I'm guessing that the majority of the 13mA is flowing through the output stage, but it could be less than that.
The idea that an amplifier has to operate in class A to provide the best possible performance is a bit of a myth. Properly biased class AB is every bit as capable. It's all about implementation.
Jake, Bill and George,
I'll add you guys to the list this evening, as jleaman has given up his boards, there are now enough for all of you.
That means we're up to 42 of the 44 available boards, so there are two left up for grabs.
Cheers,
Owen
I'll field a few questions:
null object:
As qusp correctly stated, this is indeed a class AB design. Each buffer draws roughly 13mA at idle but can deliver in excess of 250mA peak. That means the amp is generally in class A operation up to about 200mA output (because there are 8 parallel devices), and then transitions to AB. Keep in mind that the above numbers are approximate as I don't really know exactly how the current is distributed in the buffer. I'm guessing that the majority of the 13mA is flowing through the output stage, but it could be less than that.
The idea that an amplifier has to operate in class A to provide the best possible performance is a bit of a myth. Properly biased class AB is every bit as capable. It's all about implementation.
Jake, Bill and George,
I'll add you guys to the list this evening, as jleaman has given up his boards, there are now enough for all of you.
That means we're up to 42 of the 44 available boards, so there are two left up for grabs.
Cheers,
Owen
Pushing the envelope
>>That means the amp is generally in class A operation up to about 200mA output (because there are 8 parallel devices)
That means, I suppose, that no person will ever listen to a pair of these bridged across headphones where they break into class AB (with the possible exception of CaféNoir).
In other words, Null Object, if you want class A and prefer headphones, qusp's goldfish is safe as long as you fully populate the buffers.
>>That means the amp is generally in class A operation up to about 200mA output (because there are 8 parallel devices)
That means, I suppose, that no person will ever listen to a pair of these bridged across headphones where they break into class AB (with the possible exception of CaféNoir).
In other words, Null Object, if you want class A and prefer headphones, qusp's goldfish is safe as long as you fully populate the buffers.
Actually, I would buy just the boards and the heatsinks for the output buffers right now and the parts later on from Digikey.
So please put me on for 2 boards with heatsinks for output buffers if you sell them.
Do
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sigh.... not only was buying boards and anything else never a possibility, but almost every second post in the last 2 pages has been stating how many were left and then that there were no boards left.
wow.....
these group buy threads would be an interesting thesis for psychology
sorry pinnochio, its just that we have been talking about just how little information posted in these threads actually gets read and/or digested. over in the headphone amp thread right now and many others before, its the same and it seems impossible to combat.
wow.....
these group buy threads would be an interesting thesis for psychology
sorry pinnochio, its just that we have been talking about just how little information posted in these threads actually gets read and/or digested. over in the headphone amp thread right now and many others before, its the same and it seems impossible to combat.
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To focus or not to focus, that is the . . .
It really izPartly my fault. pinnocchio has been paying attention to the JC-80 thread and I was trying to stay as ON thread as I possibly could over there. Especially when we were trying to 'recruit' John Curl. Then, finally, following Null Object's class A Q&A I blurted it out. Sorry pinnocchio.
It really izPartly my fault. pinnocchio has been paying attention to the JC-80 thread and I was trying to stay as ON thread as I possibly could over there. Especially when we were trying to 'recruit' John Curl. Then, finally, following Null Object's class A Q&A I blurted it out. Sorry pinnocchio.
