120 Volt psu PreAmp - lowest possible G-FeedBack

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2N5551 pin config - Watch Out!

thanks Bonsai 🙂
no comments really needed ... or

I attach the pin configuration of my output transistor 2N5551.
This is important!!!
Because uses not the normal European small signal Transistor pinning.
The Philips Holland type.
Like for example BC550 BC547 BC546 etc

See image!
Lineup
Lineup Transistor Info

hehe 😎
 

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TOSHIBA 2SC2240 - Japan Transistors for Low Noise Audio

.
TOSHIBA Transistor Silicon NPN Epitaxial Type (PCT process)
2SC2240 Low Noise Audio Amplifier Applications

As you can see this great & fantastic audio transistor from JAPAN & Toshiba
has got another pinning than our normal European Philips standard.
(As mentioned 2N5551 used different, too)

Besides TRANSISTOR PINS, base collector emitter, you can see data of this transistor used in my 120 Volt amplifier.
Terrific data.

Actually, it is the Max Voltage ratings of 2SC2240 that set my choice of Voltage Supply = 120 Volt. BC550C, Max 45 Volt, is useless in these high voltage amplifiers
SC2240 .. TO-92
Collector-base voltage VCBO 120 V
Collector-emitter voltage VCEO 120 V
 

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New Version comparing feedback & without feedback

.
New 'improved' version.
Harmonics spectra shows basically same graph as my first posted FFT.
The comparing test of my first version. ( see above)

The only harmonic being tiny bit better is 2nd without feedback.
Notice especially the Ratio of 2nd/3rd, in both tests.
( those 2 freq maybe truly perceived by one human ear/brain )

With very low feedback turned ON, all higher harmonics ( 3rd-> ) are clearly damped,
while there is some little more of the 2nd.
When running my 120 Volt pre amplifier at high voltages output,
I would personally TURN the very Low FeedBack ON 🙂

This test, as can be seen in TITLE of my Fourier Analysis,
was at MAXIMAL Nominal input/output Voltage:
1.0 Volt RMS input & 20 Volt RMS output
.

Regards 🙂

>>> Lineup Audio LAB community <<<

schssss .. quiet ... schssss
 

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Input pair mounting as by Lineup

which I can recommend.

Sure is good if those two Audio 2SC2240 from Japan
can be very close friends 😀 😀
... is good for precise operation ... and distortion cancelling

I have used this many times 😉
And will work.
As did this time, tooooo, hoho :eguitar: :king: :cheers:
.. will give away some nice practical tricks .. for all
like you have your own audio tricks .. will work also good, I suppose
 

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now something completely else, as destroyer X 'once' said

....
how is Sweden, my country, in August ... where I live 😎

something like this, I can tell ... from my window

later after 2-3 months I show you some more COLDER :snowman: :snowman2:
like White Christmas

:drink: :drink: heheeee!!!
 

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120.0 Volt Precision regulated DC Voltage ....

for accurate pre amplifier work !!!

We discuss my discrete 120V power supply ( there are not many good IC regulators for this )
at Our Audio Community.
Unless you know a very good alternative 120 Volt DC supply,
I can recommend you to check out (must sign up = use same username as here)
lineupaudio forum

Regards 😉
 
Lycklig Svensk - Happy Swede

what you know of my country sweden
maybe not too much
but i know many from germany, norway, holland
comes to visit as tourists

also german & norwegian persons buy houses in sweden
for holiday & getaway from other 'more crowded' european countries
( we have not many inhabitants per square kilometer in sweden - at least not as in netherlands 😀 )
.. and we have a lot of 'untouched' wilderness
= nature as it should be = without any people = only nature + animals

Here you can make a virtual visit
to the snow in one swedish place in the north - where i live
Try this 😎 panorama IMAGE using java:
http://3dfoto.se/pano/

🙂 🙂

Attachment:
One very Happy swede - Fishing with his best friend, his dog
 

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120 Volt Pre Amplifier

... what we have so far

Ouput results were posted in Post #50.
In my FFT Fourier Analysis comparing with low fb vs. without feedback.
😎 At maximal nominal output of 20.00 Volt RMS ( +- 28.3 Volt peak ) 😎

Of course the output distortion figures at for example line level 1.0 Volt RMS,
are much lmuch ower .. at all harmonics 😀
See this link:
http://www.diyaudio.com/forums/showthread.php?postid=1600528#post1600528


And those who follow my articles will know the basic conceptual circuit well 😉
See attachment here below !!!
Note: Lineup Audio LAB reserves 100% all rights for our own use!!!



:hphones: :hphones: :hphones: Lineup audio community
 
Better image people hehe

this image is better looking and will give you the complete idea
of this real hi-fi amplifier without boring Op-Amp sound :devilr:

OPA627 has got not much to compete with
when best DISCRETE Designs comes along
and AD797 is put in the past now.

cause ... The Times They Are A Changin'

..... Sorry John Curl you have to use & discuss those AD797!
But what can you do, when you are not into your own DIY Audio,
but have to conform to Amplifier Manufacturers (stupid) limitations :bawling:
Take Warning People!

We who are free men at Lineup Audio LAB can have a look at my DISCRETE circuit:
 

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Nice lineup,

Similar to something i am using as preamp except 1 less tranny, the cfp with the mosfet is my vas and buffer, one less stage. Kinda like Aleph, just 2 stages. Sounds pretty good.
Now I am playing around with a blowtorch type input design but mosfet cfp second stage. The mosfet cfp sounds very good and I have used it with succsess in a Classs AB power amplifier as drivers in the outputstage and also in class A outputstage. It works pretty good in diamond buffer output stages too.
 
😉
yeah, yeah, well
try to measure the weigth of different harmonics
using +- 28.3 Volt Peak (total 56.6 Volt AC swing) output signal
from one OPA627 or one AD797 or whatever LMxxxx 😀
.... and compare your figures to my discrete amplifier output
I guess the DISTORTION is quite :devilr: Heavy
... as those Op-Amps has no more than ~35-45 Total Supply Voltage
........................................................................................

The Image attachment "Anything Goes" is from our forum at Lineupaudio.com
... probably would scare the heiellll out of some of the admins here at diyaudio forum
:devilr: 😱 😱 :devilr: ... no further comments needed :clown: 😀 :clown:
 

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