APE EQ PCB (See video sample)

[ForthMonkey]

€60 for one mono channel.You will get four frequency boards,four voltage follower boards,one PSU and one main board.Totally you will get 10 boards for one channel.

€100 for stereo set.You will get eight frequency boards,eight voltage follower boards,two PSU and two main board.Totally you will get 20 boards for one channel.

Shipping fixed to €7.

Video Sample

https://www.youtube.com/watch?v=V3iyq_F2kY0&feature=youtu.be

I re-designed.I'm trying easy to build,cheap and useful unit.

Freq_Board_Schema

https://dl.dropboxusercontent.com/u/91809016/APIsh/Freq_Board_Schema.pdf

Main_Board_Schema

https://dl.dropboxusercontent.com/u/91809016/APIsh/Main_Board_Schema.pdf

Voltage_Follower_Schema

https://dl.dropboxusercontent.com/u/91809016/APIsh/VF_Schema.pdf

PSU_Schema

https://dl.dropboxusercontent.com/u/91809016/APIsh/Power_Schema.pdf

Calculated Gain Resistors

https://dl.dropboxusercontent.com/u/91809016/APIsh/GAIN_RESISTORS.pdf

Front Panel

https://dl.dropboxusercontent.com/u/91809016/APIsh/APE_FP.rar

 

[volker]

Not opamps, they are unity gain buffers. Look at the schematic in this post. At the bottom there is a dashed rectangle. This three-transistor circuit is placed for every one of those 'A's in the schematic. You could use an opamp buffer of course, signal to +, - connected to output.

 

[ForthMonkey]

Not opamps, they are unity gain buffers. Look at the schematic in this post. At the bottom there is a dashed rectangle. This three-transistor circuit is placed for every one of those 'A's in the schematic. You could use an opamp buffer of course, signal to +, - connected to output.

Thanks! I got it.And i made low mid band with this buffer and it's good.I added first post.

 

[ForthMonkey]

Now i finished all circuits and i will combine them.But where can i find 2520 footprint to making PCB?

 

[culteousness1]

But where can i find 2520 footprint to making PCB?

Maybe DIY?

Cheers,
Carsten

 

[ForthMonkey]

But where can i find 2520 footprint to making PCB?

Maybe DIY?

Cheers,
Carsten

Yes! I will build 2520 for dip8.

 

[ForthMonkey]

But now i have help.For design i used TL072 but i will use 2520.It's discrete.I need to convert it to op amp schema like other LTspice op amps.Cause 2520 is big.

 

[ForthMonkey]

BTW i will use potantiometer for gain.Cause i'm trying to build cheap and easy version.

 

[Spencerleehorton]

Hi,

Is this a 550b eq?

Could you post some pictures?

Regards

Spence

 

[Majestic12]

Hi,

Is this a 550b eq?

Could you post some pictures?

Regards

Spence

I don't think there are many pictures to post since this project has just started and there's nothing more available than the schematics.

 

[ForthMonkey]

Hi,

Is this a 550b eq?

Could you post some pictures?

Regards

Spence

I don't think there are many pictures to post since this project has just started and there's nothing more available than the schematics.

Yes there is only circuit now.And now i'm trying to combine all section.I will add full circuit and PCB.Then i will wait for parts. ;D

 

[Spencerleehorton]

Hi,

Very interested in this as I have built 4 x api312 and want some eq units to compliment them.
If your able to send me any info on all this that would be fantastic.
4 band dual concentric pots I do need to source.

Regards

Spence.

 

[ForthMonkey]

Hi,

Very interested in this as I have built 4 x api312 and want some eq units to compliment them.
If your able to send me any info on all this that would be fantastic.
4 band dual concentric pots I do need to source.

Regards

Spence.

Now i re-draw circuit.

 

[ForthMonkey]

Now i finished design.I will create two PCB.One for switches and one for main.For now it's unbalanced but i will add in&out transformers.

 

[Spencerleehorton]

great news, cant wait to see something.

regards

Spence.

 

[ForthMonkey]

I hate making PCB. I can't! But still trying...

 

[ForthMonkey]

Someone said that i will make PCB for you but he is gone...I don't know why...I think i have to do it my ownself.I'm still learning.I hope i can figure it out.

 

[ForthMonkey]

Added last version circuit.

 

[ForthMonkey]

I added control board.It doesn't fit 500 series but still small.Actually i can't find dimensions of 500 series.This size is ok?

Size: 2.349 x 5.089 inch

 

[ForthMonkey]

Design is done! I will build about 1-2 weeks.Waiting for parts.I hope prototype will work...