Active baxandall doesn't change tone

[ismailcay]

Hello everyone,

I've built this baxandall network  http://effectslayouts.blogspot.com/2018/04/active-baxandall-network.html
It passes signal but tone control doesnt change anything. I followed exact layout except 10uf caps, I dont have 10uf so used 4.7uf
What could gone wrong?

[ismailcay]

Here are some pics
https://imgur.com/gallery/SxKEfcE

[iainpunk]

hey, welcome to the forum.

i believe i see atleast two leads that aren't soldered to anything.

also i suggest you look at this link:debugging guide

cheers, Iain

[ElectricDruid]

Welcome Ismailcay!

i believe i see atleast two leads that aren't soldered to anything.

I thought that too, but it's a TL071, so it shouldn't actually matter. Or did you spot something else too?

[ismailcay]

Those 3 leads not supposed to connect anything. I double checked again and all connections seems good. I also found some 10uf caps and changed the 4.7ufs nothing changed.
Also Connecting or disconnecting psu doesnt do anything. Made some voltage measurements
       psu  12.8 
pin1 10.81        pin8  11.75   
pin2 0.45          pin7 12.8
pin3 6.5            pin6 0.5
pin4 0               pin5 0.08

[ismailcay]

Allright, solved the problem, changed ic with only one side of the ne5532, working flawless. Now onyle question is my tl071's not working ? or they just doesny work with this circuit 

[tonyharker]

The NE5532 is a dual Op Amp.  The TL071 only contains a single one.  The circuit is for a dual device.  A TL072 would work also.

[antonis]

http://effectslayouts.blogspot.com/2018/04/active-baxandall-network.html

Particular layout clearly calls for single op-amp..!!
No dual op-amp clould work despite its positioning..

[ismailcay]

Tried four tl071, none of them worked, so I placed a ne5532 on breadbord and jumpered one side to socket then it works. Im so confused

[bartimaeus]

try removing the ne5532 altogether, and see if anything changes. seems like it should still pass signal with no opamp, via the negative feedback path.

[ismailcay]

try removing the ne5532 altogether, and see if anything changes. seems like it should still pass signal with no opamp, via the negative feedback path.

yes it still passes the signal but almost no tone shaping.

[iainpunk]

the 5532 is a DUAL opamp. the 071 is a SINGLE opamp, they have differing pin designations, and can't be interchanged on a layout or pcb that's designed for the other.

looking at the layout, the 5532 would have no supply voltage, and several opamp pins are floating, this whould work as if there is no chip at all in the socket.

cheers

[ismailcay]

the 5532 is a DUAL opamp. the 071 is a SINGLE opamp, they have differing pin designations, and can't be interchanged on a layout or pcb that's designed for the other.

looking at the layout, the 5532 would have no supply voltage, and several opamp pins are floating, this whould work as if there is no chip at all in the socket.

cheers

This Layout designed for single opamp use and people verified it. Opamp you see on the image is tl071 and layout shows that pins open.
And of course tl071 and ne5532 not interchangeble, I put ne5532 on breadboard and used it as single opamp by using jumper wires.

[Rob Strand]

This Layout designed for single opamp use and people verified it. Opamp you see on the image is tl071 and layout shows that pins open.
And of course tl071 and ne5532 not interchangeble, I put ne5532 on breadboard and used it as single opamp by using jumper wires.

Check the wires to the bass control.   Also make sure you have connected the inputs of the NE5532 the right way around.

Good idea to wire the unused NE5532 opamp as a buffer then wire the + input to Vref via a 4k7 resistor.

FWIW, the cap values for the bass and treble look wrong for an active Baxandall.   The different cap values are what you see on a Passive bass/treble control.  The caps won't affect your DC issues.