Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 9th August 2003, 02:05 PM   #1
diyAudio Member
 
Join Date: Aug 2003
Location: Prague,Czech Republic
Thumbs down One or two transistors

I dont know,if this problem here presented is meaned seriously or only like "brain exercise".In every times amplifier buildt with "nonideal" device will have "nonideal" parameters:high output impedance,high distortion,low slew rate(narrow frequency response),poor temperature stability etc. Nonideal parameters will lead to the nonideal sound:bass like "throwing of the ***** to the tent(ladyes and moderator certainly execuse me,but this word is mostly accurate),nonconvincing middles and "tail of distortion" on trebles. In our country we have one proverb:"You cannot do the ball by the fart" and I am sorry, but all this "dreamly project" is very similar to this proverb. I know whatabout I am talking-amplifiers are my hobby and I am buing it many years. Pavel(Paul)
  Reply With Quote
Old 9th August 2003, 03:39 PM   #2
halojoy is offline halojoy  Sweden
On Hiatus
 
Join Date: Nov 2002
Arrow I preafer 1 Transistor Single End

I prefer 1 amplifying transistor,
if possible Single End, SE
if I can get it to work properly and cope with loads.

If not,
I add another transistor, to co-operate in best possible way
with the first.

halojoy has more than 1 transistor in most of his constructions
  Reply With Quote
Old 11th April 2012, 08:51 PM   #3
diyAudio Member
 
Federmann's Avatar
 
Join Date: Oct 2009
Location: Kunovice - Moravia
Send a message via ICQ to Federmann Send a message via Skype™ to Federmann
I also prefer fewer transistors. One is correct.
  Reply With Quote
Old 11th April 2012, 08:59 PM   #4
sreten is offline sreten  United Kingdom
diyAudio Member
 
Join Date: Nov 2003
Location: Brighton UK
Hi,

According to Einstein "Everything should be as simple as possible, but no
simpler". Too simple is as bad or worse than too complicated, YMMV.

rgds, sreten.

Good simple 2 transistor circuits tend to slaughter any single device option.
__________________
There is nothing so practical as a really good theory - Ludwig Boltzmann
When your only tool is a hammer, every problem looks like a nail - Abraham Maslow

Last edited by sreten; 11th April 2012 at 09:08 PM.
  Reply With Quote
Old 11th April 2012, 09:01 PM   #5
Boscoe is offline Boscoe  United Kingdom
diyAudio Member
 
Join Date: Feb 2010
Location: England
Quote:
Originally Posted by halojoy View Post
I prefer 1 amplifying transistor,
if possible Single End, SE
if I can get it to work properly and cope with loads.

If not,
I add another transistor, to co-operate in best possible way
with the first.

halojoy has more than 1 transistor in most of his constructions
Quote:
Originally Posted by Federmann View Post
I also prefer fewer transistors. One is correct.
Sounds great ^.
__________________
I thought about it once, but then thought again.
  Reply With Quote
Old 12th April 2012, 04:57 AM   #6
CBS240 is offline CBS240  United States
diyAudio Member
 
CBS240's Avatar
 
Join Date: Aug 2005
Location: K-town
Quote:
Originally Posted by sreten View Post
Hi,

According to Einstein "Everything should be as simple as possible, but no
simpler". Too simple is as bad or worse than too complicated, YMMV.

rgds, sreten.

Good simple 2 transistor circuits tend to slaughter any single device option.
each component must have a relative function to justify it being in the circuit. If it is of not much cost and effort to add a transistor, like perhaps a cascode for the VAS to eliminate Early distortion, and to utilize a high Ft high Hfe device (typically small Vceo) for the VAS, then it is better to use another transistor. Sometimes the extra benifit is not worth the cost/effort. That is for the DIYer to decide.
__________________
All the trouble I've ever been in started out as fun......
  Reply With Quote
Old 12th April 2012, 09:15 AM   #7
DF96 is offline DF96  England
diyAudio Member
 
Join Date: May 2007
Use the right number of transistors, if you know how to. If not, either buy something which has been designed by someone who does know how to, or use valves!

PS it is unlikely that one or two is the right number of transistors, unless you like listening to lots of low order distortion and you have high efficiency speakers in a small room.
  Reply With Quote
Old 12th April 2012, 03:28 PM   #8
CBS240 is offline CBS240  United States
diyAudio Member
 
CBS240's Avatar
 
Join Date: Aug 2005
Location: K-town
Agreed. Knowing what transistors are suited to which task is important.
I have been experimenting with common mode FB loops biasing a complementary trans-impedance VAS driving a constant impedance with some excellent results. It requires a few more than two transistors to acomplish this tho....
__________________
All the trouble I've ever been in started out as fun......

Last edited by CBS240; 12th April 2012 at 03:30 PM.
  Reply With Quote
Old 12th April 2012, 03:42 PM   #9
diyAudio Member
 
Federmann's Avatar
 
Join Date: Oct 2009
Location: Kunovice - Moravia
Send a message via ICQ to Federmann Send a message via Skype™ to Federmann
Click the image to open in full size.

Here are four transistors.
  Reply With Quote
Old 12th April 2012, 04:46 PM   #10
diyAudio Member
 
VibroKing$'s Avatar
 
Join Date: Dec 2009
With ideal components would be enough 3 transistors for perfection.
but theory is a simplified model of reality and reality is much more complex.
for comparison if you want to fly you need an airplane.
If you want to go to moon you need a complex spaceship.
If you want a good amp you must use appropriate solutions.
Also spice is a simplified model of reality
Sometimes an amplifier that seems to work perfectly in numeric mode
in reality is just an oscillator
__________________

  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
old RCA transistors- what are they? needtubes Parts 13 23rd July 2012 09:43 PM
what transistors to use? prorms Solid State 1 20th November 2006 05:14 PM
Best transistors YUTK Solid State 1 20th May 2005 04:16 PM
transistors Dj BASS AMP Solid State 1 31st March 2003 04:46 PM
transistors lemondog Swap Meet 5 1st March 2002 07:05 PM


New To Site? Need Help?

All times are GMT. The time now is 12:07 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2