Lowpass filter for subwoofer

[audioguru2]

Frt,
This project's schematic, its parts list, its pcb layout and its photo don't agree with each other. It would be a fairly big job to sort it all out. We don't even know if it works.
Similar projects are on the web and are presented more clearly and are fully completed.

 

[MP1]

frt,
I suggest that you contact the author of the project at his email address:
[email protected]

He will be able to tell you about his tests of the project and also will be able to give you details of the parts that he used for the project. It seems that this is the basis of your questions.

MP

 

[balong]

hellow!!!!
                experimenting on your projects can really help!!! and it will increase your knowlege about electronics!! and also dont forget to put some personal
touch in your projects. because as far as i know also in my opinion electronics
is modern art. ok !!!

 

[MP1]

I agree belong, however, it can also cause your project to go up in smoke if you experiment the wrong thing. As staigen pointed out, it is helpful to find tutorials and to read some publications before jumping into something you are totally clueless about.  pfoooof!!!!
If you let the smoke out of the circuit, it will not work 

MP

 

[zak4000]

HI!!

The 22k pot. on the PCB is wired up differently than the schematic!?
Wich ones right? ???

 

[audioguru2]

HI!!

The 22k pot. on the PCB is wired up differently than the schematic!?
Wich ones right? ???

Hi Zak,
Welcome to our forum. ;D
The 22k pot is a dual pot. Maybe you found another problem with this project.
I said it before about it: "This project's schematic, its parts list, its pcb layout and its photo don't agree with each other."

 

[zak4000]

havnt been here for ages 

anyway, ive finished this project (almost) lol, and i dont hav a 39pF cap so i used a 56pF metallized caps for now, works ok... you might need a preamp on the output as well

you only need 4 100nF ceramic caps
what are the 180nF and 100nF metallized caps for?

you dont need high voltage caps as the project only needs 2x 9v (or about that) batteries to run

 

[audioguru2]

Hi Collin,
Many people are confused with the errors in this project. It is too bad nobody fixed the mistakes in the parts list and on the schematic.

The parts layout drawing is correct except the LED is shown backwards.
Look at the picture. It clearly shows ceramic capacitors and metallized plastic ones.
Here are my notes:

 

[audioguru2]

Please do not make duplicate posts. I answerered your questions about our Lowpass Filter for Subwoofer project in your other post.

The parts list and schematic in the project are still wrong. The parts layout and picture are correct. The LED is shown connected backwards on the parts layout.

 

[MP1]

The 3 capacitors on the right hand side of your picture are tantalum. Not ceramics.

Collinph: I have moved all of your other posts into this thread. It only confuses everyone when you post your questions many different times in different places. Also, there is a link from the project to read the posts. These are only pointed to one place, so everyone would miss some of your posts if I allowed them to be made in other places.

You can also click on the author's name in the project and ask questions directly if you still have confusion. Much of the confusion is caused when a project is translated from one language to another. Little things like silk screen imaging printed backwards is just something we have to live with when getting free projects from the web. This is part of the reason for this forum.

MP

 

[audioguru2]

The 3 capacitors on the right hand side of your picture are tantalum. Not ceramics.

I have seen many 39pF ceramic capacitors, but never a tantalum capacitor with such a low value.

 

[collinph]

Thank You So Much Sir.........

 

[MP1]

They are certainly not ceramics. With a closer look by enlarging the picture, I see these three are not all the same capacitor type. The 39 pf has a different appearance. The 100 nf caps are tantalum and the 39 pf cap is a silver mica.
In looking at the schematic this also makes sense due to the purpose of each.

MP

 

[audioguru2]

Pick a capacitor type, any capacitor type.
The 39pf capacitor is a ceramic, not an old silver mica.

 

[MP1]

Use what you want, but your picture doesn't even agree with your statement. Sure looks like the more squared silver mica than the very small round ceramic to me.
;D

All fun aside, the silver mica will be better. I use them in microcontroller crystal applications where more precision of frequency is required than what a ceramic will give. Silver Mica is not an "old" cap. They are widely used in everyday electronics.

MP

 

[ante1]

The appearance of capacitors differs between manufacturers and these might very well be ceramics. When repairing many different types of equipment one encounters various brands and learns to see the differences and similarities.

 

[audioguru2]

Why doesn't somebody fix this confusing project so that the schematic, the pcb layout and the parts list agree????????????????????????????????????????????????????????????????????

Or else just dump this project.