Discrete Single End TRUE Class A HeadPhone Amplifier

[lineup]

.

Hello lovers of diyAudio

My Headhone Amp project
for you?

Schematic and detailed description is a part of
Destroyer X very good topic:
http://www.diyaudio.com/forums/showt...007#post997007

Enjoy da Musica!

Here is my lineup original idea,
with Component layout of my circuit
( please respect my full copy right to this amplifier )

[sparkle]

only to be more confortable to look and read - here is the sch from that thread.....

it will make a very nice amp for small headphones or Grado's - much better than what i was using to play with.....

[sparkle]

o.k. - to keep this thread allive - it will be a pitty to loose it so quickly - nice small amp ....
i have drawn a clearer schematic ...maybe lineup will correct me if i have made a mistake somewhere....
regards
daniel

[DorinD]

What could you say about the thermal drift which is essential for an A class amplifier?
I said that because the current through BC557 (and so on) seems too sensitive by temperature for my taste. Have you sense any change in sound over some time of continous functioning?

[destroyer X]

My resistance to construct it immediattely is because the power consumption.....as i will have to produce a supply, and this means that will not be portable anymore...attached to the mains...hummm...not good to MP3 player...as will need to be fixed.!

I am thinking to reduce voltage and current, to recalculate the whole thing to lower voltage transistors, and to use Nickel Cadmiun batteries, and i have a lot of them..all brand new..costed 1 dollar each one...950 miliamps each unit..AA sized.

The circuit may sound very good, as it is simple and class A...and with differential that we can try to make better that feedback line.

Yes...batteries may be noisy...but we can try to filter that noise.

regards,

Carlos

[sparkle]

Dear DorinD,
i am sorry but i did not build this little thing...it is entirely made by Lineup....he will be back in a couple of days and i am sure that he will answer Your question....
I assume that You don't have to worry because he made it and he reported that the sound is simply wonderfull.....
best regards
daniel


my dear Carlos....i am happy that you are interested in this amp....yes i agree with you that the consumpiton is a little bit to much for the batteries...but i have a small transformer in my home that has (i think) the proper voltage needed for the amp and the transformer is not to big....i think this still can be preety small for class A...small enough to be used with my laptop....
i am looking forward on what you will do...(smaller fo the batteries) - but i am courious if this will destroy some of the magic - maybe it will.....
regards

[sparkle]

o.k. guys....
i have received a very nice mail from the guy that started this thread (thanks lineup for the kind words).....
i will quote him - it is the best.....


======================================
about my amplifier:

you see the load is 100 Ohm.
In fact the omtimal load for this type of class A is
resistors = headphone impedance

this will give maximum output power
and this means, setup is also the best QUALITY low distortion
performance
when load is = resistance in output stage

My output stage, is in fact compromise,
for amplifier to be good form 32 - 300 Ohm headphones

100 Ohm is in middle*!

formula:
if LOW = 32 and HIGH = 300 Ohm phones, you want to use
square root( LOW x HIGH ) = 97.79 Ohm

so, if you want to make special version for 32 Ohm
and lower voltage, it can be done
no problem
only some matematicals and some thinking
and some little changes

*************

lineup

====================================

best regards and happy diy

[lineup]

sparkle
thanks for your schematic clean-up
http://www.diyaudio.com/forums/attac...amp=1157628903


Just for fun
here is how an electronics program wants to arrange PCB layout.
I wouldnt build it like that.
I have shown a drawing in a previous post here,
my idea of a perfect placing of components onto a board.

Anyway
here is the computed suggestion
from a good but a bit stupid electronics program.
You know such programs, just like some people,
have very low ability to think out of the box

Newbies and audio beginners, still have plenty of this quality.
As they are not yet inside the square and improved box of accepted audio ideas.
This is one reason, I like so much to exchange ideas with new diyAudio members.
Good for my creativity

lineup

[destroyer X]

Good analisis and evaluation of some people behavior...... they are exceptions....not a rule.

Your posts are different....better in my point of view, as they show that there's a human being in the other side....not a computer terminal writing things...a real man in the other side.

One added to one will be not always two..... if those ones constitute a couple.... married persons...this can result in three, four, five or more...including the kids....in electronics can be applied to many things...including harmonics.

A little bit more flexibility using the brain, is more than adequated.

Sparkle is sick...he is facing a storm in his life, i am not sure if he will be able to answer you Lineup

regards,

Carlos

[lineup]

Originally posted by destroyer X

Sparkle is sick...he is facing a storm in his life, i am not sure if he will be able to answer you Lineup
regards,
Carlos

Very sorry to hear this, Carlos.

He was very understanding and helpful to me, when I started this topic
and was waiting in house-arrest for 10 days.
Planet10 was also a great comfort to me. Dave is alright.
Hope things will get better for Sparkle.
As far as I can tell, our friend does not deserve to be not happy and feeling bad.

regards
lineup