70mW make the temperature of the transistor increase 14°c above ambient temperature. And the rest you already know ... the Vbe decrease the power increase and so on , this forms a positive feedback mechanism. You need to add emitter resistor or similar measure , to degrade this thermal loop.
Damir offers a superb preamp. He gives commentary in excellent English.
But a couple of people criticise it in an almost personal way.
Ease off, guys. Why would creative people bother with this sort of academic carping? We are lucky to have Damir here, and his temperament is wonderful after these sharp comments.
But a couple of people criticise it in an almost personal way.
Ease off, guys. Why would creative people bother with this sort of academic carping? We are lucky to have Damir here, and his temperament is wonderful after these sharp comments.
AKSA , I don't know if you are referring to me, but my only intension is helping Damir, English is not my. Primary language , so maybe the words that I chose are not the best ones.
No, Sergio, not you at all.....
However, this is not a witch hunt, I am simply highlighting the behaviour and since this is a very good design (in my view!) I think we should say that. Most of the comments are fine points, I'm confident the sound quality would be exceptional, just like Damir's power amplifier.......
However, this is not a witch hunt, I am simply highlighting the behaviour and since this is a very good design (in my view!) I think we should say that. Most of the comments are fine points, I'm confident the sound quality would be exceptional, just like Damir's power amplifier.......
I agree this is a great design, very similar and sure inspired by sergios designs. I like it a lot.
Actually it was inspired by Satri circuit and I designed this pre amp first http://www.diyaudio.com/forums/analog-line-level/223835-current-conveyor-voltage-amplifier.html
If I connect thermaly Q13/Q15 and Q147Q16 thermal drift is completely compensated. Maybe better to rearrange the PCB, as emitter resistors increase distortion.
Michael you are one of the few people that have see my préamp design, so, for sure Damir was not inspired by me 🙂.
if someone besides Damir deserves credits is Keantoken that have intruduce this type of mirror based on the baxandall pair. And as I see it, the heart of this circuit is real the mirror that is very linear.
Yes Keantoken is the one to helped me a lot and I said that in my first current conveyor thread.
Sorry sergio... things seem to go in circles.. Anyway I do admire the work both of you do.
Sergio, I have some outstanding values in a riaa to send you, sorry for the delay.🙂
Sergio, I have some outstanding values in a riaa to send you, sorry for the delay.🙂
🙂 ok. Michael, we have to finish the riaa amplifier, I manage to get a turntable, but with a MM head. Need to do some modifications to the amplifier circuit to accept both types of heads , as I can not invest in a decent MC head right now. It has been a wile the last time I use a vinyl disk in my home, so I am curious to try it again after all this year's. Send me a mail when you can.
Could you show or open a thread for RIAA amplifier MM and MC, I have both pickups actualy two turntables.
What I can say is that the phono amplifier is based on a very linear current conveyor, it does not use a feedback loop, and it has a gain of more than 10000. The input has very low noise, so we are very pleased with the great potential of the circuit.
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