Good news. Don't give up on the follower transistor yet, if it can fit in steadily, it boosts the performance. You may do a before and after listening test and decide better when finished. Can you upload a shot of your interesting total configuration?
It seems that's rarely the case. From what i understand most R-cores are wound in a balanced manner.
A while ago I compared an R-core transformer with some toroid transformers in an experimental tube preamp project. Although R-cores have much lower capacitance between primary and secondary, there was not a big difference in sound quality between the R-core and a toroid of about the same VA rating. But there was a distinct difference when I compared bigger VA ratings. The bigger the transformer the better the sound! And this was not by a small margin. This pre was never built but I ended then with a 500VA (230V sec.) toroid with fast rectifiers and only about 50uF of smoothing capacitance before the voltage regulator and it sounded wonderful!
Peter
Peter
Hi Peter,
Any theories about why the bigger transformers sound better ?
Does this extend to Power Amplifiers also ?
My only comparison of transformers was between similar specified torroidal & EI transformers when developing a power amplifier. They were about 200VA & 18VAC + 18VAC. In this A/B comparison the EI transformer sounded MUCH better.
These days I always used comprehensive filtration in all legs after the bridge and this makes the different types of transformer almost indistinguishable but I am interested to understand your findings more.
Any theories about why the bigger transformers sound better ?
Does this extend to Power Amplifiers also ?
My only comparison of transformers was between similar specified torroidal & EI transformers when developing a power amplifier. They were about 200VA & 18VAC + 18VAC. In this A/B comparison the EI transformer sounded MUCH better.
These days I always used comprehensive filtration in all legs after the bridge and this makes the different types of transformer almost indistinguishable but I am interested to understand your findings more.
Hi Mikelm,
Yes this also extends to power amplifiers. In power amplifiers it is better beef up your transformer than to enlarge smoothing capacitance (generally). I can not proof that with theory, but I think that it is an advantage to have fast charging times. So: big transformers, fast (soft recovery) rectifiers and just enough capacitance.
Peter
Yes this also extends to power amplifiers. In power amplifiers it is better beef up your transformer than to enlarge smoothing capacitance (generally). I can not proof that with theory, but I think that it is an advantage to have fast charging times. So: big transformers, fast (soft recovery) rectifiers and just enough capacitance.
Peter
Well, Peter that is an interesting perspective which I will definitely check out . . . . but it makes be laugh a little bit to hear this because it is so different than that which I would expect to be the case but I know from experience that I can believe your advice.
My personal PSU philosophy is more along the lines of " if the type of transformer can make a difference . . . . then the post transformer line regulation measures to filter out mains noise / diode switching / secondaries resonance etc . . . just aren't working well enough ".
Funny we should chat again today because only yesterday I was trying to implement a LM285Z-2.5 that you recommended to me when we were discussing LDR volume controls. Only in this case I could not get a good result from it - in fact in this case - a green LED gave much better measured result. I will PM to you - perhaps you can tell me if I made an error.
thx
mike
My personal PSU philosophy is more along the lines of " if the type of transformer can make a difference . . . . then the post transformer line regulation measures to filter out mains noise / diode switching / secondaries resonance etc . . . just aren't working well enough ".
Funny we should chat again today because only yesterday I was trying to implement a LM285Z-2.5 that you recommended to me when we were discussing LDR volume controls. Only in this case I could not get a good result from it - in fact in this case - a green LED gave much better measured result. I will PM to you - perhaps you can tell me if I made an error.
thx
mike
Of course. I'm very agree with you an Pietjers; big txs are more important than big capacitance. My very personal theory about big txs, is that big VA have little resistance and
lower impedance. Like in the shunt reg, lower is the out impedance, better is.
lower impedance. Like in the shunt reg, lower is the out impedance, better is.
@ nicoch.Sta una meraviglia . I listened his studio monitor and I made the RPG like diffusors for him.
@ Salas. Sorry , I don't understood.What's the loop area? Do you intend the cabling between tx,diodes bridges and filtering caps?
@ Salas. Sorry , I don't understood.What's the loop area? Do you intend the cabling between tx,diodes bridges and filtering caps?
As a follow up:
Electricity can only flow in circuits. What goes out, MUST come back in.
In our circuits there is always a return route for a flow route.
Those flow and return make up a pair. That is the pair that should be low loop area.
It applies to mains cables. It applies to LV AC supplies from a transformer. It applies to LV DC supplies from rectifiers. It applies to signals, whether single ended or balanced. It applies to every circuit where electric current flows.
Electricity can only flow in circuits. What goes out, MUST come back in.
In our circuits there is always a return route for a flow route.
Those flow and return make up a pair. That is the pair that should be low loop area.
It applies to mains cables. It applies to LV AC supplies from a transformer. It applies to LV DC supplies from rectifiers. It applies to signals, whether single ended or balanced. It applies to every circuit where electric current flows.
Zobel of Reflektor +3.3V
After long journey I reached the goal to serch for Zobel of Reflektor +3.3V.
The story is following.(Of course no oscillation on all cases)
1) 2R2+2.2uF
Not bad, no harsh, but sound dim.
2) 2R2+0.22uF
Become brilliant, but harsh.
3) 0R47+0.22uF
Become decent, but still a little harsh.
4) 0R47+0.44uF(0.22u//0.22u)
Become great deep sound, no more harsh.🙂
I also guess that it is very good for 1R0+0.47u as Salas recommends.
On this experiment I found a few principles about Zobel.
1 Zobel is strongly related to quality of sound.
2 If Zobel is not been optimized, sound become harsh or dim.
3 The optimal value is between the narrower area than I expected.
Next step, I build Reflektor +1.2V. If I get good result, will report.
Best regard
After long journey I reached the goal to serch for Zobel of Reflektor +3.3V.
The story is following.(Of course no oscillation on all cases)
1) 2R2+2.2uF
Not bad, no harsh, but sound dim.
2) 2R2+0.22uF
Become brilliant, but harsh.
3) 0R47+0.22uF
Become decent, but still a little harsh.
4) 0R47+0.44uF(0.22u//0.22u)
Become great deep sound, no more harsh.🙂
I also guess that it is very good for 1R0+0.47u as Salas recommends.
On this experiment I found a few principles about Zobel.
1 Zobel is strongly related to quality of sound.
2 If Zobel is not been optimized, sound become harsh or dim.
3 The optimal value is between the narrower area than I expected.
Next step, I build Reflektor +1.2V. If I get good result, will report.
Best regard
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