[spaceconvoy]

 
I have a Mini3 already built (high performance version), and I'd like to add a bass boost but I'm hopeless with any electrical engineering. This is as far as I've figured out, which is basically just the PPA bass boost grafted onto the Mini3:
 

 
I'm planning to snip the leg of the existing R4, then run two wires to the extra bass boost circuit. Size isn't an issue for me, and I'm going to buy (or make) a bigger case to fit everything, with the bass boost circuit installed on perf board next to the existing Mini3 board.
 
I used Tangent's calculator to figure out the value for RX and CX, but I'm not sure if the existing R5 will effect things, since the PPA circuit doesn't have a resistor in that place. Also, I'm not sure if I need to change the value of the pot, since RX is so much higher than in the PPA circuit... see, I told you I was hopeless
 
Can anyone tell me if there's something wrong with this plan, and how I could fix it? Or is it possible that I've actually figured it out properly???
 
...
 
Also, if I want to add crossfeed, could I wire it in front of R1? Or would placing it after the volume pot cause problems? It would be easier than trying to scrape the trace away and attach new leads to the board in the tight space between the input and the volume... Thanks!

 

[m1abrams]

This is probably a very bad idea for the mini3. The opamps used are extremely picky and any extra inductance in the feedback will most likely make them unstable. Adding a bass boost by creating a bypass circuit in the feedback would most likely make the amp unstable.

 

[hashina]

 Many more thans for ur great idea reg. xtra bass boost adoption circuits in a Hi-Fi stereo  audio system .It works very well with good stability & punched bass  effect without disturbing entire audi spectrum. Also i added cross feed circuit before this circuit. with little xta  modified circuitry  i certainly feels realism of hi fi effects.I add this modified circuit in my  own 8.1 ch SDDS  surround system for better thundering bass effects. thanks.
 With best regards.

 

[amb]

Quote:

This is probably a very bad idea for the mini3. The opamps used are extremely picky and any extra inductance in the feedback will most likely make them unstable. Adding a bass boost by creating a bypass circuit in the feedback would most likely make the amp unstable.

m1abrahms is exactly right.