Schematic Elements for Guitar and Effects: Opamp Stages, Boosts, and the MXR MicroAmp

Comments · 23

• MR

  @MrBlockHead · 1 year ago

  This video was helpful. I’ve learned a lot about op amp circuits but didn’t quite understand about the caps in op ap gain section.  You earned a sub

  2

• BL

  @Blaculo · 3 years ago

  Awesome explanations.  Thank you.

  1

• PA

  @paatyki · 1 year ago (edited)

  Hi, I found your channel totally by accident and I decided to sub it &apos;cause you talk about things that interest me in a very accessible way. Thank you very much for that. <br>But to the point. <br>When describing the elements of the non-inverting op amp stage, you did not mention another important role played by the C3 capacitor in this topology.<br>In addition to limiting the bandwidth from the bottom, it divides the negative feedback loops separately for DC and AC signals. <br>Why is it so important?<br>Op amps are not ideal components. Small imperfections like few mV offset voltage at the input multiplied by a very high gain of circuits like overdrive, or booster can cause a large constant voltage at the output, which interferes with the operation of other elements, for example clipping diodes . This is why we use C3 cap at feedback loop. &nbsp;So for AC signals, as you explained in the movie, the gain is determined by the ratio of impedance (R4 C2 ) to (R5 R6 C3) and can be very high, while for unwanted DC signals, the feedback loop is closed only by the resistor R4, which means that the gain is only 1.

  2

• SO

  @SoundSeeker2024 · 3 months ago

  Excellent! Thanks!

• RO

  @rogerw4024 · 1 year ago

  Great explanation, like why the resistor is so high to bias the op amp, after watching this video im starting to get a better grasp on these simple circuits. Appreciate you sharing your knowledge and time!!!

• SA

  @satselab · 1 year ago

  Great video and precise explanations!

• CD

  @cdecdecdecdecde · 3 years ago

  Really good walkthrough, thanks dude!

• PA

  @patrikdunmar8022 · 1 year ago

  ❤

• 66

  @66Gollum · 1 year ago

  Thank you again, this was very clear - but why is &nbsp;R5 soo big, as far as I understand it will reduce the output If pulled up?

• PE

  @Pentode3000 · 2 years ago

  R9 is NOT to be omitted!!! It decouples the TL072 from capacative loads like a long guitar cable. The TL series has a tendency to oscillate with capacitive loads. I would suggest a minimum of 100 Ohms. Overall good explanations but you should pay more attention to those RC Filter relations. Making C1 bigger will absolutely do nothing for the bass response if you leave R2 and R1 the way they are. On the other hand you will cut bass if you put 100n in for C5 and leave R10 as 10k.

  7

• GE

  @Get.Wired.Studios · 4 years ago

  Just an edit, your gain pot lugs 1 and 2 should be connected together rather than 2 and 3. The way you have yours wired, turned the pot all the way down (counterclockwise) would be maximum gain and turning it all the way up would be minimum gain.

  2

• DM

  @dmilotte · 3 years ago

  Great info, do you build this pedal in another video?