A comparison between a Bazz Fuss and a Big Muff Pi modified stage.
The Bazz Fuss plot shows two curves, one with one diode and the other with a pair of back to back diodes.
The BMP-like stage has almost the same topology and working voltage.
As I noted in one post long ago, the diode in the Bazz Fuss can't clip and bias well at the same time, so it's better to add a Vcc to base resistor given by Rbase = hfe*Rc, and then fine tune Rc until Vc=Vb, which is the Bazz Fuss tuning condition.
Arsenio Novo's desing has the same tuning condition. It's a kind of Bazz Fuss.
But instead of fine tuning a Bazz Fuss oftenly, I tried the BMP way and found out that results are... well, quite similar.
Breadboard and have fun!
BF schem
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50534&g2_serialNumber=1)
BF plot
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50537&g2_serialNumber=1)
BMP schem
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50540&g2_serialNumber=1)
BMP plot
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50543&g2_serialNumber=1)
mac
Mac. I'm a little confused... I know you like to bias the base with a resistor, but here I see that blocked with a diode.
Can you explain the graphs? Are we seeing that the bazz fuss soft-clips the positive and nearly square-waves the negative? Does this account for the synthy tones the bazz fuss occasionally produces?
QuoteMac. I'm a little confused... I know you like to bias the base with a resistor, but here I see that blocked with a diode.
Note that the modded big muff has a R7=1000k resistor from C to B ;)
QuoteCan you explain the graphs? Are we seeing that the bazz fuss soft-clips the positive and nearly square-waves the negative? Does this account for the synthy tones the bazz fuss occasionally produces?
Not much to add, you answered yourself :)
The BF has two simulations, think Rs as a on/off switch:
- Rs almost zero, both diodes connected, yellow trace, which is similar to the BM.
(Note that BF has no negative feedback resistor as the BM)
- Rs almost infinite, only one diode working, blue trace, soft clipping up, hard clipping down.
mac