Ancient amplifier, the old sound as some reference

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Last days i am thinking about reference.... i imagine that is a good idea to say:

That amplifier have better treble than JLH
Those amplifiers sounds alike JLH

As JLH designs appear to me as a reference, of course i am searching one that can beat JLH, and of course i can believe it can be beated.

But, for a while, it is my reference, not a perfect reference, as it is not perfect, cannot produce good power to compare in other power levels, and sometimes both amplifiers running class A because the low power under test.

This way i go back to the sixties, when the sound where not good...as I remember, not so good.... and i capture some brand schematic and made changes and some small update...but do not think the mods i made could change too much the signal patch.

It is a "terrible" amplifier.... electrolitic condenser output (i use one 220N in parallell in my prototype), no diferential input, one stage coupled with capacitor!!!!..... a damn shame amplifier.... to remember how we evolute those last 35 years.

In simulation it surprised me, from 28 to 112 Khz flat without distortions in waveforms.... the square wave not so square... a little bit "eroded" in its corners.... some undershot here or there, but an old "horror" to made us happy with our new amplifiers when comparing...this is a "bad" reference. 3dB power loose was under 12 hertz...triangle sinusoidal started in 120 Khz....we can say 30 to 80 Khz, low distortion, colored sound, 50 watts RMS ancient "terrible" amp.

Using this one you will say...not this one...but something terrible alike this one you discover worst than this one (let me know, please) .... you will say:

- "Changing that capacitor in my leach amp, the sounds turns so awfull as mine "terrible" reference one!

I made it in a spider bed shape assembly, and i am hearing.....hehe.... will say nothing... do it yourself and tell me...please.... tell me directly..... surprise!!!!

Maybe, our fathers or our grandfathers, were not so bad as we imagined.

regards,

Carlos
 

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Adjustment points

You can use a 30 plus 30 supply, or a 35 plus 35 volts supply...use the plus and minus and put there one electrolitic condenser of at least 3300 uf/70 volts.

The adjustment points, to the output line voltage (half the total voltage) and the bias adjustment resistor is showed.

Use a trimpot to adjust the output line voltage....a 220K unit, and use one 100 ohms trimpot to adjust bias...it will work in the mid position...the 100 ohms resistor i put in parallel with the first diode is to help you to adjust the bias easily.

Good Luck!

Carlos
 

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quasi-complementary amps

Yes, it might be ancient technology but they really sounded good,
much better than certain complementary "modern" designs with
by-railed supplies.
A very good example of this ancient tech is Quad 33 power amp.
Or one of the first JLH amplifiers, which I built, by the way.,..
This was a true "blameless" amplifier....
I miss both. In my search for a better amplifier I disassembled
the latter and I sold the first.....
 
hohohô, i do not know even to measured those harmonics without spectrum analiser.

And i have not..... do not know how to use Multisim to do those analises....really ignorant i am related those matter.

My ears where surprised...my bad reference not bad... i changed the hi speed transistors by the worst units i have here.... and unmatched on purpose.... resulted the same...could not perceive difference.

No, "the bad and the evil"... the ancient ressurrector from deep cave, is using BD130/140, BC548 (not even BC549) and 2n3055....i reduced the voltage and adjust the bias to the threshold of conductivity.... to create some problem.

Try it.... i am sure we will respect those that talk about Williamson and others strange things.

Hapiness in Paradise to Mr. John L. Hood!

regards hohohohô

Carlos


The Napalm too.... have to receive money... this is fair.
 
Two images of poor transistor

Sorry, i have no digital photo machine..... it is too expensive... cost my monthly income the good Sony model.

And i am not poor, as a King i leave in a nice apartment in front of the beach, swiming pools, 2 cars, a maid and a very confortable live to Brazilian average....but those photo machines, the good ones, are too much expensive.

Sorry, my images is made over the scanner... not good images.

regards,

Carlos
 

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Quasi - complementary ? No, complementary !

My apparatus in the year 85' was good ( I was thinking, that is good ). I was using active crossover ( 18 dB / oct state variable, switched by 1 / 3 oct ) and my amps was Tiger 001 ( " little brother " of well known Tigersaurus, 60 W ) on bass and middle. On trebles was here known JLH ( 12 W, both rails with voltage stabilisers. With this sound I was very satisfied and I was thinking, that only a few amps may be little better. People mean, Gods change. My friend had carry from USA kit of amp Hafler DH 220. This was sure first mosfet amp in our country ( at this times mosfets was starting ) and I was very curious, how will be his sound. When I had connect this amp to my chain ( instead JLH ), after several tacts of music I had in my head quite clear, which will be my next " audioway " - JLH was only poor relative. Yes, it is in comparative good amp, 'cos exist more bad amps, but who claim, that it is miracle, to this time don't hear some quite good amp. I'm sorry my friends :cool: , but before twenty years I was on the same position.
 
Good Epuppa!!!!, i was thinking what happened those years.

As i could not hear nothing better than JLH.

My English is no good as you know, and many others already perceived ... hehe

I could understand that you could find good amps that can compare or beat the JLH.

When i talk JLH, normally i do not talk complementary, because i prefer the old one.... only one transistor working....NPN exactly biased in perfect point!.... those simetrical i think loose i little, but the differences are not great in my mind, because the increase of power create some illusion that disturb my own evaluation... some dinamic turn the modern ones much better in comparison.

But reducing the level, to stay under the "small" JLH ancient limits....my God.... tell me please the ones beat that amplifier.

I will try to find them and to hear them....the JLH is my reference amplifier, but Rio de Janeiro was the most pretty city in the world, till the day i land in Honolulu - Hawai... this way my beauty city reference changed.

Of course i want to find, desperately, some amplifier that can beat JLH!, because is a shame for our generation...more than 30 years without beat this old design is a hell shame on us.

And there's tube amplifiers always ahead , still beating all complicated solid state design.

Some people shown me others, i tried them, but do not think they were better.

If you can, please, tell me the names and models and i will try to hear them.

This amplifier, the ANCIENT BURN!, bias drift and overheat, send it to other world, and his last parts were buried with respect, as a good sounding old veteran amplifier must be treated. I was hearing a good flute music when he left his last breath.

regards,


Carlos
 
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