Distortion by Amplification

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Distortion - Google Drive

Please, inform whether the files can be opened.

Half asleep, I have managed to made some files to record sound from the guitar in different scenarios. All of the files are made with a single channel computer microphone placed near the amplifier. A few settings have been used for the different files.

I have to repair the guitar which I hope to do soon. So far, there is fret fuss on the lower frets of the thinnest string ( F#, G, G# ) a distorted version of which can be heard in the file which gives normal maximum distortion without any distortion induced noise ( other than the 60Hz and 120Hz noises ).

The computer fan was near and noisy.

The pickups have not been change and will soon be. Now, the sound of the 4th ( D ) string and the third ( G ) string is louder because the poles of the pickups are high and the strings are plain steel and give a good output and there is no need for higher poles.

There is a file which shows how the plain guitar ( without any effects and preamplifiers, just the guitar directly into an amplifier which is not a guitar amplifier, just a general purpose one.

Hope to make other records when I fix the guitar.

Forgot to make a record of the distortion with a preamplifier before. Becomes nicer. Hope to do this soon.
 
In case anyone is interested, I have done some more experiments, which, are very difficult to do in the environment I am in and working on many projects, switching from one to another, etcetera.

So, I connected the guitar to a preamplifier which has a huge input impedance ( TL072, JFET inputs connected as a buffer ). I wanted to compare whether there is any audible difference between the guitar directly to the distortion and then to the amplifier and the buffered guitar by the preamplifier and then to the distortion and then to the amplifier.

I am unable to make the difference out because the preamplifier can only go to a gain of 2 and not 1. So, I have to compare whether something, amplified by 2 is the same as another thing, not multiplied by 2. As you can realise, this is difficult.

The idea of this experiment is to find the signal loss caused by the high output impedance of the guitar and low ( ~ 100K ) input impedance of the distortion. I would be able to do so somewhat more easily provided I had a preamplifier with a gain of 1 to be used as a buffer.

I have also played the guitar connected to the preamplifier adjusted to have a gain of 3 ( would hopefully not go to saturation at this low gain ) and the preamplifier connected to the distortion and the distortion connected to the amplifier. The sound is marvelous and, the noise level is lower because of the low output impedance of the preamplifier. I can still hear the power supply noise which I hope I can decrease by a power supply which I am in a process of physically making.

Also, I have moved the whole setup to be away from the PC ( with an open enclosure ) and I can now position the distortion to the maximum gain and still not have any significant noise.

I also intend to soon put 1N60P saturation protection to the input Darlington transistors.

Hope this was interesting.
 
Just tested the distortion without the preamplifier in the new position away from the open enclosure PC.

Sounds OK. Works without abnormal noise ( like before ) with maximum gain too.

The thinnest E string ( 1st string ) sounds weaker but, maybe, I imagine. Need to play more to say. The same frequencies on other strings sound OK.

Again, the coil poles are not adjusted well. Will do soon, hopefully.
 
I have designed, made, improved and tested a very simple, transistor based distortion effect for guitars ( can be used for anything, I guess, but I have so far never tried to use distortion on anything else than a guitar ).

I have written a simple document which is written at a very basic level and explains why 2 and 2 is 4 and not five. I will be happy to have people who want to read the whole document, but, most of the people would only want to read the addendum where the schematics and the pictures are.

Here is the document. Please, inform whether the link can be open by anyone :
Distortion Amplification.docx - Google Drive

Please, because the document may be updated, do use this, more general, link which gives access to the Documentation folder where the file is as well as to any other folder related to the project.
 
I have made some slight changes on the schematics. The buffer transistors have been protected against saturation. Hope 1N60P is fast enough. The capacitance is 2pF, maximum 6pF. Cbe of the transistors is unknown and is expected to be the standard for low power 5pF.


Most importantly, I have replaced the old power supply with a regulated switching power supply and most of the noise has been eliminated.

I have made a new test file with the distortion connected directly to the line in of the PC.

The file goes through a few settings of the distortion and overdrive gain : minimum, middle, maximum without noise, maximum. These settings are for Distortion and then again for Overdrive. The first set of tests is with a preamplifier with a gain of approximately 3 and without saturations. The second set is with the guitar directly connected to the PC without a preamplifier. The very last section is the guitar directly connected to the PC without any distortion, overdrive and preamplifier. I have still not fixed the guitar.

The device goes from minimum to maximum and offers a few different sounds. I prefer the highest gain of distortion without excessive noise.

I have not used any other distortion than this one since I made this one.

Again, here is the link to the documentation and tests :

Distortion Amplification - Google Drive




Here is the l
 
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