Hi
Here I started working preamplifier with ECC83!
For starters here are wooden boxes

 

Hello all!
Something i recently worked and managed to create this Tube Premplifier with ECC83 (12AX7)?
View Post: Circuit for preamplifier with 12AX7!
Here's my work looks like this:

 

Cool!
One of my first projects I built when I was 16 was a darkroom timer using a 6SN7.

 

Cool!
One of my first projects I built when I was 16 was a darkroom timer using a 6SN7.

"OK"!???
Human stupidity is infinite,..... and the univers?
For I am not sure unvers,....??!
Einstein
Cheers !

 

Hi
Not to be all the way,.... this is how the second harmonic is!
And the frequency response is here!
thanks

 

The very old tubes preamp has pretty high distortion. The second harmonic is a 0.5% distortion and the third harmonic is at 0.1%. The distortion will get worse as the tube wears out.

Why is there a 5dB peak at 30kHz? Why does the circuit produce 50Hz, 100Hz and 200Hz hum?

If you use an audio opamp (OPA2134 dual or better) then the total distortion will be only 0.00008%. The distortion will not get worse. The response will be absolutely flat up to about 100kHz. There will not be any hum.

 

If everyone got rid of audio distortion then Rock music would sound HORRIBLE.

 

If everyone got rid of audio distortion then Rock music would sound HORRIBLE.

A lot of rock music sounds HORRIBLE to people who weren't deafened by its terrible distortion. Deaf people can't hear the high frequencies where the distortion is located.

 

Cool!
One of my first projects I built when I was 16 was a darkroom timer using a 6SN7.

"OK"!!!
man's stupidity is endless ...
thanks

Why a response like this?

 

A lot of rock music sounds HORRIBLE to people who weren't deafened by its terrible distortion. Deaf people can't hear the high frequencies where the distortion is located.

Spoken like an honorable man who has never played a rock guitar riff with the amp turned up to the 'mythical' 11.

 

A lot of old people don't like rock and roll, just some of them get cranky about it.

 

The very old tubes preamp has pretty high distortion. The second harmonic is a 0.5% distortion and the third harmonic is at 0.1%. The distortion will get worse as the tube wears out.

Why is there a 5dB peak at 30kHz? Why does the circuit produce 50Hz, 100Hz and 200Hz hum?

If you use an audio opamp (OPA2134 dual or better) then the total distortion will be only 0.00008%. The distortion will not get worse. The response will be absolutely flat up to about 100kHz. There will not be any hum.

Distortion is the second harmnic 0.78% at 2kHz! To get the right one Valve/Tube sound!! At 30kHz the elevation of 5dB due to losses in the cables?
Noise (hum) at 50Hz, 100Hz and etc so is the equipment (from the computer sound card "Creative Sound Blaster Audigy SE").
Cheers

 

Distortion is the second harmnic 0.78% at 1Hz! To get the right one Valve/Tube sound!!

No.
The input is 1kHz so the second harmonic is at 2kHz. It is shown at 46dB down so its is -6dB (half) of -40dB (1%) which is 0.5%.
I know that vacuum tubes (valves) produced high even-order distortion that some people like.

At 30kHz the elevation of 5dB due to losses in the cables?

No.
Capacitance of cables will cut high frequencies, not cause one frequency to be boosted. I don't know why until I see the schematic.

Noise (hum) at 50Hz, 100Hz and etc so is the equipment (from the computer sound card).

Hum is usually from using AC for the filament. Some people use filtered DC for the filament to eliminate hum in one of these very old circuits.

 

Audioguru, your remarks somewhat wrong!?
Power the filaments tubes with a well filtered DC-voltage (2x6,3Vdc) - noise (hum) is >88dB below!! (see measuraments with CLIO!) Second harmonic (even harmonics) gives one a real warm sound that Valve is great for introducing!!
Cheers

P.S.
Here are the measurements from profi device CLIO!
Figure A and Figure C.

 

Audioguru, your remarks somewhat wrong!?
Power the filaments tubes with a well filtered DC-voltage (2x6,3Vdc) - noise (hum) is <88dB below!! (see measuraments with CLIO!) Second harmonic (even harmonics) gives one a real warm sound that Valve is great for introducing!!
Cheers

P.S.
Here are the measurements from profi device CLIO!
Figure A and Figure C.

I disagree with you because my first preamp and power amp used vacuum tubes about 48 years ago and my newest solid state amplifiers have much less distortion that does not get worse which happened when the vacuum tubes wore out.

An amplifier is not supposed to produce any audible distortion. 1% second harmonic or more is terrible. Listen to a live orchestra or singer and there is NO distortion just like a modern amplifier.

Vacuum tube power amplifiers have an output transformer that rolls-off low and high frequencies. It adds distortion. The output impedance is up to 1000 times more than a modern solid state amplifier so the resonances of speakers are not well damped.

 

Dear AG,

A HIGH FIDELITY amplifier is not supposed to produce any audible distortion. A transistor amplifier for guitars produces so little distortion that it sounds terrible to the musicians. After they are done performing, you are welcome to listen to it with a hi-fi amp. On stage, you couldn't sell a no-distortion amplifier for a penny a watt.

The world has more than one kind of people in it, and judging by the billions of dollars spent purchasing music from distorted amplifiers, I think there are several people that disagree with you. I hope you don't feel as bad as you sound when you are grousing about distortion. I wouldn't want this issue to affect you health.

With all respect, #12

 

Personally, I'm glad that there's young folk out there that still appreciate the old girls. This argument is about as pointless as those who like liver and those who would rather eat road pizza!

 

I have also noticed that speakers and enclosures for them made for electric guitars are also horrible.

 

AG, I don't think that you'll ever have to worry about being dethroned as AAC's most contrary, cranky and argumentative (I may miss some adjectives) member. I thought Canadians, with all that clean air, were generally mellow? You gotta get out more.... Maybe fishing?

 

AG, I don't think that you'll ever have to worry about being dethroned as AAC's most contrary, cranky and argumentative (I may miss some adjectives) member. I thought Canadians, with all that clean air, were generally mellow? You gotta get out more.... Maybe fishing?

I live in a suburb of Toronto in southern Canada. Most "clean" air comes from the polluting coal burning electricity stations in Illinois (USA). Near me they destroyed the last coal burning electricity station a few years ago.

I am not mellow because I get out too much. I see too many new immigrants who are scary-looking.