P701
New Head-Fier
- Joined
- Nov 11, 2013
- Posts
- 43
- Likes
- 16
Greetings!
I recently got into "DIY scene" by building my first amp, CMoy (the most basic version of it). I'm planning to build a new one (and "better") with rail splitter, vground buffers, powered from wall psu and 2 opamps/channel. But some questions I still do have, that I have not managed to quite figure out.
Firstly, here is a picture to the most simply looking circuit of what I had in mind for the circuit of opamps:
http://i43.tinypic.com/15s6d5v.png
1
I've heard that using more than one different sized (big & small) bypass caps in power circuit is better than only one alone, would there be any dis/advantages to use 2 or more ac-coupling capacitors (C1) in parallel for the input of the opamp? (eg. 0.22uF & 0.68uF)
As those AC coupling capacitors along with R1 creates highpass filter, I would guess that atleast the response on the low frequency would be better, would there be any other effects to sound?
2
For the output resistors in the OP Amp, should they be connected like in the picture, or so that the resistors were in "loop" with opamp output pin and inverting input pin? (moving the connection point for inverting input to the other side of resistors R2 & R3)
In CMoy they are other way as in my picture, but I've seen it done like this way when using more than one opamp.
And would 10 Ohms resistors be sufficient?
If I made the other resistor higher valued than the other, would the lower valued op amp affect the sound more than the one with higher valued resistor?
And a question regarding to this type of circuit:
http://i42.tinypic.com/t8kfpe.png
3
In some schematics I've seen a capacitor added to the OP Amp gain stage like this. What is the purpose of it and how does it affect to sound itself?
I had a guess that since capacitors have higher impedance in low frequencies than higher frequencies, it would boost the Bass or dynamics along with the resistor thats connected parallel with it?
As when lower frequencies kicks in, the impedance goes higher over the capacitor forcing the opamp to make more gain?
Another pic regarding to next question:
http://i43.tinypic.com/kdaafb.png
4
In OP Amp input I've seen a capacitor (decoupling capacitor?) added like this with a resistor in parallel. I'm wondering what does it do and how does it affect the sound?
If you actually managed to read this all, I thank you for your time and would apperciate any answers to the previous questions.
I recently got into "DIY scene" by building my first amp, CMoy (the most basic version of it). I'm planning to build a new one (and "better") with rail splitter, vground buffers, powered from wall psu and 2 opamps/channel. But some questions I still do have, that I have not managed to quite figure out.
Firstly, here is a picture to the most simply looking circuit of what I had in mind for the circuit of opamps:
http://i43.tinypic.com/15s6d5v.png
1
I've heard that using more than one different sized (big & small) bypass caps in power circuit is better than only one alone, would there be any dis/advantages to use 2 or more ac-coupling capacitors (C1) in parallel for the input of the opamp? (eg. 0.22uF & 0.68uF)
As those AC coupling capacitors along with R1 creates highpass filter, I would guess that atleast the response on the low frequency would be better, would there be any other effects to sound?
2
For the output resistors in the OP Amp, should they be connected like in the picture, or so that the resistors were in "loop" with opamp output pin and inverting input pin? (moving the connection point for inverting input to the other side of resistors R2 & R3)
In CMoy they are other way as in my picture, but I've seen it done like this way when using more than one opamp.
And would 10 Ohms resistors be sufficient?
If I made the other resistor higher valued than the other, would the lower valued op amp affect the sound more than the one with higher valued resistor?
And a question regarding to this type of circuit:
http://i42.tinypic.com/t8kfpe.png
3
In some schematics I've seen a capacitor added to the OP Amp gain stage like this. What is the purpose of it and how does it affect to sound itself?
I had a guess that since capacitors have higher impedance in low frequencies than higher frequencies, it would boost the Bass or dynamics along with the resistor thats connected parallel with it?
As when lower frequencies kicks in, the impedance goes higher over the capacitor forcing the opamp to make more gain?
Another pic regarding to next question:
http://i43.tinypic.com/kdaafb.png
4
In OP Amp input I've seen a capacitor (decoupling capacitor?) added like this with a resistor in parallel. I'm wondering what does it do and how does it affect the sound?
If you actually managed to read this all, I thank you for your time and would apperciate any answers to the previous questions.