We were talking about the characterization of the device itself, not how it’s used in a system. BJT’s are not transconductive devices. Show me one data sheet where the collector current varies by Vbe.
No, I was referring to amplifiers, ie that is how the devices are used in an amplifier system … turn to a bipolar transistors specification and you will sometimes see the VBE/IC bipolar transistors characteristic chart
The Ebers-Moll equation shows us that IC is determined VBE rather than IBE, but as a graph there are many other variables such as temperature coefficient/temperature, VCE etc.
So VBE is related to IC by the Ebers-Moll equation… and because of this there are typically severeal charts deconstructing the equation.
I refer you to the Art of Electronics, if you are interested… in detail description of bipolar transistor device transconductance and the Ebers-Moll transistor equation… a very good read albeit designed for the electronics engineer… and has some good thought provoking exercises and applications to help identify common design errors. Some of my other engineering buddies have equally well thumbed copies 
When referring to a device, we always talk about its characterization of that device in isolation. It’s doesn’t matter how it’s used. There can be nearly an infinite number of implementations.
That graph just shows you that the transistor “works” when Vbe is above about 0.6 volts, and doesn’t below. Only useful if you’re designing a switch. (And not too many use in that manner since this value varies slightly from every device and by temperature).
The curves you are interested in when designing an amplifier are the ones where the collector current varies by the base current. This is where you can operate the BJT in the linear region.
FETs are very different in that they vary the output current based on the input voltage through the gate.
I totally agree… very different characteristics… and as far as the linear region, indeed that is the flat slope part of the IC characteristic… and yes we bias for the middle part of the load line for linear amplification of small signals… but it is a composite curve/chart that is derived from the transconductance principles… remember IB is derived from VBE
Ooooh, am I? 
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But Ib isn’t the property in which we are interested in reality
Vbe causes Ibe to flow. It’s Ibe (not Vbe) that injects electrons (for NPN) into the depletion zone in the base layer. Under the field effect of Vce in the depletion zone these injected electrons undergo accelerated diffusion into the collector. In other words the physical controlling parameter is Ibe not Vbe.
Vbe is used in Ebers-Moll equation as a mathematic convenience to substitute for Ibe.
Note also that hFE is defined as Ic / Ib; it is therfore dimensionless.
Wow,just wow…I am completely lost here. This is like a prize fight,using brains instead of fists.
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I was lost at quasi-complimentary.
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I also read that the amps are all in Class B. Does anyone know if this is the case?
I’m just lost. Does it sound any good?
Naim power amps are class AB.
That strikes me as quasi-complimentary (rather than quasi-complementary)! 
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Anyone with a PhD in semiconductor physics knows that MOSFETs are voltage controlled and BJTs are current controlled.
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Or just a weird mind like mine!
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Alan, that is the right interpretation. We learnt a lot from thatstore and their listening events during those years. They only sold Linn, Naim, NAD 3020, Boston A40 speakers and modified IKEA Lack tables. They always started with what you had at home and how to set everything up correctly. For us it was a new world of music reproduction at home.
The store is still there with new people and still handle Linn. One of the original guys still handled Naim (no other brand) on his own a few years back when he helped me with servicing and some purchases.Probably retired now.
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Naim amps have never been much about that stuff. Many of the early cb/olive amps used basically the same circuit. Naim has been about getting the basics right … grounding, resource supply, tweaking the circuit so it handles the required current - and then component selection.Very special, very clever.
GaN Transistor / Mosfet? possible…right
This reminds me a serie of books.
Knuth was considered as a “guru” along with Richard Stallman.
This was a long time ago 
Yes good point, maybe the actual circuit thats doing the “job” isn’t the relevant part? Just getting that part into exactly the right environment.
Possibly I have no personal experience in specifically using gallium nitride transistors… but I understand they can be used in more efficient power applications compared to silicon based semiconductors. Perhaps others may be able to comment.
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