Volume loss after adding BMP tone stack to Fuzz Circuit

[BennyBoy]

C2 was in the original fuzz that I based this of off, but that fuzz had no tone control. When I built this without the tone control (or the 3rd gain stage) that capacitor kept the tone much more low end oriented, but perhaps I don't need this with the BMP tone stack.

What do you mean about T3? That was also in the original fuzz circuit that I based this off of.

In this application, T3 cuts off one halfwave of the signal, like a diode.

So T3 is there for clipping?

[antonis]

What do you mean about T3? That was also in the original fuzz circuit that I based this off of.

Could you plz post a schematic (or a link) of the original circuit..??

[Dormammu]

So T3 is there for clipping?

Sort of.

[BennyBoy]

What do you mean about T3? That was also in the original fuzz circuit that I based this off of.

Could you plz post a schematic (or a link) of the original circuit..??

Here it is!

[antonis]

Ahaaa..!!! We're talking about Devi Ever Hyperion Fuzz..
(your Tina-TI schematic confused me a bit..)

[BennyBoy]

Ahaaa..!!! We're talking about Devi Ever Hyperion Fuzz..
(your Tina-TI schematic confused me a bit..)

Yep! Sorry, I am new to using programs to draw circuits.

[antonis]

Sorry, I am new to using programs to draw circuits.

On the contrary, I'm the one who oughts to apologize..

[BennyBoy]

Thanks again for the help! Do you have any other suggestions about how to maybe improve the circuit? I'm hoping to build it this Friday when my parts come in!

[antonis]

Do you have any other suggestions about how to maybe improve the circuit?

Only minor ones..



You see, "improvements" in such kind og circuits are of strictly personal taste..

[duck_arse]

a Devi Ever design - can't believe there is still some [old hands] here can't recognise when they pop up.

I'd like to point out there is a DC path to ground through the added on tone section, a cap added after R5 and in series with R7/C4 would clear the problem, but it hasn;t been mentioned by the others, so, carry on!

and another welcome.

[antonis]

but it hasn;t been mentioned by the others, so, carry on!

[BennyBoy]

a Devi Ever design - can't believe there is still some [old hands] here can't recognise when they pop up.

I'd like to point out there is a DC path to ground through the added on tone section, a cap added after R5 and in series with R7/C4 would clear the problem, but it hasn;t been mentioned by the others, so, carry on!

and another welcome.

Thanks for the welcome, duck! Sorry, I am a bit of a newbie, but you mean adding the cap would negate the need for the muff output section, or do you mean in conjunction with that?

[BennyBoy]

Do you have any other suggestions about how to maybe improve the circuit?

Only minor ones..



You see, "improvements" in such kind og circuits are of strictly personal taste..

Thanks a ton, antonis! will try this out on the breadboard tomorrow!

[antonis]

you mean adding the cap would negate the need for the muff output section, or do you mean in conjunction with that?

Stephen means that DC across P2 might cause crackling issues..

A cap, either between R5 & C4/R7 junction or between R6 and GND, of value much bigger than the bigger of C4 & C5 should block DC coming from R5/T2/T3 Collectors..

[BennyBoy]

you mean adding the cap would negate the need for the muff output section, or do you mean in conjunction with that?

Stephen means that DC across P2 might cause crackling issues..

A cap, either between R5 & C4/R7 junction or between R6 and GND, of value much bigger than the bigger of C4 & C5 should block DC coming from R5/T2/T3 Collectors..

Thanks a ton! Just for learning purposes, what are the functions of the cap and resistor you suggested adding?

[antonis]

We proposed a cap only..
(resistors mentioned are there already..)



You can place the cao at any convenient point across the red line..
(as said above, it will block DC flowing through P2 - same happens with C1, C3 & C6..)

[BennyBoy]

We proposed a cap only..
(resistors mentioned are there already..)



You can place the cao at any convenient point across the red line..
(as said above, it will block DC flowing through P2 - same happens with C1, C3 & C6..)

Sorry, should have been clearer, I was referring to C7 and R11 in your edited schematic!

[antonis]

They form a classic 1st order passive Low Pass Filter..
Its corner frequency (-3dB point) is calculated by the 1/2πRC formula..
https://www.electronics-tutorials.ws/filter/filter_2.html

They are needed 'cause power supply (not battery powered) can never be absolutely DC..
(in the mean of zero voltage variation..)
https://www.electronics-tutorials.ws/diode/diode_6.html

P.S.
R11 (series resistor) value is a compromise between affordable voltage drop across it (due to circuit current draw) and capacitor value (for a given corner frequency) from cost/space point of view..

[antonis]

Out of curiosity..

If you are not familiar with H/LPFs, how did you manage to get your own unique EQ values..??
(just by recklessly throwing caps and maintaining resistors..??)

[duck_arse]

a Devi Ever design - can't believe there is still some [old hands] here can't recognise when they pop up.

I'd like to point out there is a DC path to ground through the added on tone section, a cap added after R5 and in series with R7/C4 would clear the problem, but it hasn;t been mentioned by the others, so, carry on!

and another welcome.

Thanks for the welcome, duck! Sorry, I am a bit of a newbie, but you mean adding the cap would negate the need for the muff output section, or do you mean in conjunction with that?

following on from my esteemed colleague [no, no, I mean antonis], a designer will carefully consider all the DC conditions needed for proper biasing a transistor stage and place resistors to produce those conditions. you come along and add a tone section with another DC path, and it will upset all the carefull considerations of the designer.

the values in your added path are way bigger than would produce a bias problem, probably, in most circuits, but in Devi Ever, or Death by Audio designs, you can never tell what is happening, or what might happen. good practise sez DC isolate the sections.