DIY Power Amplifier designing by Listening Only

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01. take one idea for power amplifier AMP
02. build one power supply for AMP
03. build one prototype of AMP
04. attach dummy load
05. power on AMP
06. if no smoke, power off AMP
07. :att'n: attach your favourite speakers :att'n:

08. power on AMP
09. play some music
10. :cool: listen carefully :cool:
11. power off AMP
12. make eventual changes in AMP according to listening result
13. repeat from 08. until satisfied

14. design complete
15. post images & schematic at www.diyaudio.com
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This way you need only one multimeter to check out voltages
and eventually one thermometer to check out temperature of heatsinks.

And you need not much more than your ears and good portion of patience.

No simulation software.
No analog or digital oscillopscope.
No datasheets and curves of one million things.
No boring technical discussions and interference from besserwissers that do no good.
No bother about strange & complicated theoretical audio unconfirmed hypothesis.
No worry about any distortion levels, harmonics, bandwidth, damping / feedback factors and other such junk.

Just build, listen, design & enjoy ;)
We should not make diy power amplifier design & construction more difficult than it is.
When it is so very easy & simple, in fact.

Lineup audio regards
Lineup Audio Projects forum, members only
 
Yep... we cannot avoid some calculations...but very basic ones.

The good judgement is made by the ears that will evaluate latter.

Human ears judge, because human ear plus brain will listen.

This kind of personal adjustment is great... all of us have competence to adjust into try and error substitution of parts..there's no one unable to do that...have only to learn basic calculations and how circuit works and biasing... some formulas of frequencies used to input filter, input capacitor, zobel filter, feedback network and a good knowledge about how miller capacitors works, mirrors, current sinks, bootstrapp and other simple things.

It is a hell easy..... but it is a hell hard.... hard work, to adjust...and we have to build two...one keept basic, and the other one is tweaked... this way you have reference.

Or the reference can be something considered good...as JLH, and to some folks the LM chips...so.... we have to tweak to make the amplifier sound better than those ones into your own evaluation and perception (taste, experience, preferences)

Never evaluate an amplifier without compare with other, we use to fool ourselves...the last one will be the better if you have not compared...the most expensive one will decided as better if you have not compared, the most sophisticated and complicated one will be considered the better one if you do not compare them with a reference.

We judge because brand is famous... we judge because others have assembled..so... must be good... we judge as good because is expensive..we judge as better because has more power, because is more pretty, we judge something you have made as better BECAUSE YOU HAVE MADE..... because you have created, assembled or designed or tweaked...humans are self centered..... so.... have not good qualities to judge...humans have not competence to judge their own things....must be...have to be a A to B blind comparison testing... you cannot know the other amplifier into the competition.... other guy will operate switches sending sound to a single speaker (of course the one result in a better conversation with that speaker will have advantage...so ...try other speaker too)...... you will never know the one is A and the one is B...... adjust both amplifier to same level of power.... you cannot see them.... dark room...just listening and sitted very confortable... cannot be feeling unconfortable, having pains, hungry, angry, nervous or anything that can disturb your listening..... the one will operate switches will say.... this is A.... now b

regards,

Carlos
 
we have not to calculate if have some other schematic to go from

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only if is a totally new design we need do any math or calculation

otherwise we an just setup the standard circuit

then use my described listening test
to tweak and modify until we get most satisfactory sound
note: this may be very different for different ears :)

Such tweaks as
- power supply diodes: silicon or schottky
- different power supply caps, values uF and Brands, like RIFA, ELNA etc.
- bias in output stage power transistors: e.g. 20 mA, 100 mA, 250 mA
- input caps, values uF, type e.g. electrolyt, polyester, polypropylene, ceramics
( yes, ceramics ... have you tested and listened .. if not, shut up :D )

you get the thing i am talking about
don't you ;)

ain't nothing new,
good audio people has done this for 100 amnd 100 of years
without any calculating, measuring and hard thinking & figuring out
without all other complicated junk overload that some geeks like to use

ordinary plain and good hobby audio and tweaking
that's it people :cool:


Lineup
Lineup audio projects, members only
 
Yeah. I agree. To :devilr: :hot: with stupid simulations, your ears
are the final judge. I built HT sub amp and know the distortion is
<.1% but woofer outputs 1% maybe 10% at 200 watts but it sounds so good :cool: ..

With full range audio I've done some crazy stuff , like change caps with the power on!!

Ceramics don"t sound too bad, Ive used them when I couldn't find mylar or silver mica in junkbox.
the only area in a amp not to use them is miller comp. in VAS
I had a amp become a tone generator once ... Blew caps like
firecrackers :devilr: :devilr:.. also at certain frequencies in the
input filter they resonate.With current sources ,ps ,bypass duties
ceramics make no differance.

It is fun and rewarding to round up all the old stereo junk on the streetcorner and build away(good for environment too!)
My present amp is a old fisher stereo 500VA 44-0-44 transformer,
scrapped hammond PS heatsink(huge),2- 12000uf caps from run over sanyo receiver,small driver heatsinks from PC monitors.
I pay finders fee (deposit)5$ for old stereo/pc so I get cheap
parts and get to see how cheaply commercial amps are made..
(no heatsinks on drivers :hot: :hot: )ha ha..

All these people on the forums who spend 1000$ on parts/cases.
shop on Ebay find old junk hafler or other commercial amp
that is broken,get circuit from Quasi,destroyer ..modify to PS in
junk amp..all done TRUE DIY for 150$ ..wife won't kick your butt for spending grocery money on new toy!


P.S. I read that you need no spec sheet on component.. BUT,you
will most likely stink up house with many:hot: :hot: burnt parts
and make your hobby expensive. Go download as many tranny
datasheets and schematics as you can possibly pirate(I have
all aussieamps.com schematics, now he gives you none.)start with 2SA-D,TIP,MJx,BD, 1N-diode,etc.Get it all , then organize,
get 20-30 thousand of them...all set. IF any here need schema
or datasheet I have 50k and will post private ip(all are PDF,high
quality and sorted.)happy building/listening.
 
How are you going to start?
Obviously you can't listen your way to a working amplifier topology, from let's say a single resistor, adding components as they 'sound'.

To have any hope of a functioning amplifier requires, thought, design, and sound numbers based engineering.

Trying to design an amplifier by purely by ear seems analogous to trying to formulate an argument against reason (which, disgustingly, I recently saw in a major scientific periodical), any attempt contradicts the very premise it's based on.
Sorry to intrude on your thread.
 
And the end result which meets all of the above requirements is ........... :D

megaphone.jpg


Instructions on how to use:-

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Yes... speaker are so bad that you really need a horn to help them

The best ones are 1 percent efficient..... so.... you pump 100 electrical watts and have as a result 1 acoustic watt... and this is the best ones...the superb ones.

When you, dear folks, start to dominate all the theories and measurements, and simulators, and spectrum analisers.... when you reach around 60 years old alike me and Mr. Line up.... both of us building, creating, designing, testing into simulator, measuring, comparing, listening and sharing informations with others you also will perceive that the solution is to listen and to adjust using your ears, even perceiving that as ridiculous today, you will revert to that basic thing after you have experienced the sophistication.

I have 48 years doing...more than 4300 amplifiers made... have worked into service places, not only audio but also Radio and also Video Tape Recordings..... the step by step adjustment were made using spectrum, scopes, distortion measurements and deviation and frequency counters and so on.

It is strange to you... also ridiculous and seems foolish..but i ensure you that after you have obtained really big experience..years doing..you will realise that simple thing...ears...human ears is the big tool... the best tool to evaluate audio.

regards,

Carlos
 
Re: Yes... speaker are so bad that you really need a horn to help them

destroyer X said:

I have 48 years doing...more than 4300 amplifiers made... have worked into service places, not only audio but also Radio and also Video Tape Recordings..... the step by step adjustment were made using spectrum, scopes, distortion measurements and deviation and frequency counters and so on.

It is strange to you... also ridiculous and seems foolish..but i ensure you that after you have obtained really big experience..years doing..you will realise that simple thing...ears...human ears is the big tool... the best tool to evaluate audio.

regards,

Carlos

With all of your experience it shouldn't be hard for you to design and build an amplifier which is subjectively and objectively superior to anything else on the market ;) What is stopping you from doing this ??
 
13. repeat from 08. until satisfied


Hi,

So you only need to do 7 once ?

It should read :

Repeat from 8 until you have run out of speakers you have blown up.
If this does not happen repeat from 8 until you run out of semiconductors.
If this does not happen repeat from 8 until you realise your going in circles.
Repeat from 8 until you get bored having no idea what you are doing.
Repeat from 8 until you realise you cannot design an amplifier by ear.

Stop and then claim you have made the best amplifier unknown to man ....

:)/sreten.
 
sreten said:



Hi,

So you only need to do 7 once ?

It should read :

Repeat from 8 until you have run out of speakers you have blown up.
If this does not happen repeat from 8 until you run out of semiconductors.
If this does not happen repeat from 8 until you realise your going in circles.
Repeat from 8 until you get bored having no idea what you are doing.
Repeat from 8 until you realise you cannot design an amplifier by ear.

Stop and then claim you have made the best amplifier unknown to man ....

:)/sreten.

Yes don't worry about the 20 volt DC offset slowly frying your speakers. You'd certainly wouldn't want to use any test equipment to measure that when the smell of a burnt out voice coil is equally effective ;)
 
After reading many threads on DIYA I think the point Destroyer
and Lineup try to make is the over reliance of some members
in simulations and refined measurements.

I have designed/ repaired both amps and speakers and find
sometimes the best ones spec. wise( i.e. .0000001%) ,are
sonically harsh and lame.This is the downfall of the cheap
commercial offerings, hot components ,caps derated 3v below
rails(most walmart electronics).

I find it refreshing that DX,Quasi,Leach can design an amp better than Sony,Onkyo,Fisher (I would like to know how DX would
know the difference between drivers ,outputs ,and other trannies
without datasheets??)

Also, the real speaker becomes a part of the amp's circuit when
operational so one is FORCED to listen when applying the
final bench test.

P.s. 20 years ago I went through steps 8-xx... too much $$$
and burned fingers too..:D
 
ostripper said:
After reading many threads on DIYA I think the point Destroyer
and Lineup try to make is the over reliance of some members
in simulations and refined measurements.

I have designed/ repaired both amps and speakers and find
sometimes the best ones spec. wise( i.e. .0000001%) ,are
sonically harsh and lame.This is the downfall of the cheap
commercial offerings, hot components ,caps derated 3v below
rails(most walmart electronics).

I find it refreshing that DX,Quasi,Leach can design an amp better than Sony,Onkyo,Fisher (I would like to know how DX would
know the difference between drivers ,outputs ,and other trannies
without datasheets??)

Also, the real speaker becomes a part of the amp's circuit when
operational so one is FORCED to listen when applying the
final bench test.

P.s. 20 years ago I went through steps 8-xx... too much $$$
and burned fingers too..:D

Which amps and speakers were specced at .0000001% ??

Of course you are right about not forgetting about the effects of a mediocre speaker on the final performance no matter how good the amplifier is ;)
 
snoopy said:
Which amps and speakers were specced at .0000001% ??
Of course you are right about not forgetting about the effects of a mediocre speaker on the final performance no matter how good the amplifier is ;)

I have posted this respectable THD of one absolute High-end speaker!!!!!
Now, compare these figures to any 0.001% amplifier, and maybe you will recognize
what you ACTUALLY listening to
( there is however one exeption - HeadPhones of very reference class - can have THD 0.1 % )

.
Shortly:
good amplifiers do not produce sound - speakers, tranducers & passive crossovers do this


I have also had this Lineup signature, not long ago:
I really believe that all this soul-searching, wondering, questioning, agonizing about amplifiers is basically unproductive
and would be much more rewarding if applied to loudspeakers instead. (Peter Aczel)
And what is not productive .. makes no big difference, at all :D :D
As this is so obvious to me, believing in some real & basic facts,
I have no need for this signature, no more ;)


Those who still believe that good amplifiers effect SOUND more than speakers,
may be could take a little break and figure their basic school math out
.. at least a little tiny bit, please ;)

Regards
Lineup Audio knowledge & experiences
first hand info for his clever members


My attachment:
vonSchweikert Hi-ebd speakers THD test
- output level 90 dB
- THD is bottom curve ... like 0.5 % .... :att'n: :att'n: :att'n:
 

Attachments

  • soundstage_thd_90db.gif
    soundstage_thd_90db.gif
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lineup, my dear friend ;)

Sorry but I wouldn't design an amp without datasheets or an oscilloscope :xeye:
Said that, I would also like to state that from many years of experience that spice simulation is ONLY a guide line.... The spread in the manufactoring proces is to big for the spice simulation results can be trusted....

Please let your feelings free :smash:
 
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