Mic, Line, EQ... Preamps

[wattaniya]

Correct.
This scheme needs positive and negative power rails.
Look at the top left corner of the PCB design, there are the 3 power connections (GND, +Vcc & -Vcc)

i saw in the website only two connection given. why is that. i'll post the image.
in the parts list there mensioned 9v dc 300ma trafo.
if i put 12v ac dual supply 1A trafo is it ok?

 

[wattaniya]

PSU for preamps and active x-overs, with different zener output voltage can be +/-12V, +/-18V...

hello apex sir
I have 12v ac 1A dual supply trafo. so for the preamp what are the changes in your power supply i have to?
can u post the top and bottom layout in pdf.

 

[eesbiboi]

power amp link circuit

greetings...

sir miles i'd like to ask if you have a schema for linking amplifiers...

thanks,
ees

 

[irvynejay]

links service manual and schematics

greetings...

sir miles i'd like to ask if you have a schema for linking amplifiers...

thanks,
ees

try here Bro


Service Manual free download,schematics,datasheets,eeprom bins,pcb,repair info for test equipment and electronics
hope it helps

 

[Fogonazo]

i saw in the website only two connection given. why is that. i'll post the image.
in the parts list there mensioned 9v dc 300ma trafo.
if i put 12v ac dual supply 1A trafo is it ok?

The transformer, is in effect, simple (no center tap), but the source is with half-wave rectified and if you enlarge the image to 400% you will see 3 out cord

 

[Hosam]

PCB size: 60x50mm

thank you Mile I build this one and its very good for sub I test it with dual TDA stereo as I build before the result was great and sub is shaking the room, here the PCB with PSU I used for it.
top:

button:

power supply from 35v:

but I still have question about two things what is AUTO used for?
and speaker input I didn't use it just use the line in again when I can use them?

 

[apexaudio]

AUTO post signal to auto-start circuit, turn amp on if signal present and turn off if there is no signal after 5 minutes.
If there is no line-out connect on your audio system, you can use signal from speakers outputs and connect to speaker input on this x-over.
Regards

 

[zeraphine]

Hello Mile, First let me tell you that your contributions to the DIY community is priceless, Thanks for all the stuff, I just need to know how I can bypass the tone control part of ML3, is there a way to turn it off, thanks in advance.

 

[apexaudio]

Hello Mile, First let me tell you that your contributions to the DIY community is priceless, Thanks for all the stuff, I just need to know how I can bypass the tone control part of ML3, is there a way to turn it off, thanks in advance.

IC1 is preamp, IC2 is EQ. Use output from IC1B out if you don't want tone controls.
Regards

 

[apexaudio]

RIAA

Phono MM preamp

 

[apexaudio]

Headphone Amplifier with TO92 MOSFETs.

 

[zeraphine]

IC1 is preamp, IC2 is EQ. Use output from IC1B out if you don't want tone controls.
Regards

Thanks Mile, Also can you post the PCB layout for the Preamp you describe on your Class A PSU thread it looks brilliant

http://www.diyaudio.com/forums/power-supplies/164365-class-preamp-psu.html#post2141076

 

[DAMANHURI]

ASK TONE CONTROLL MR APEX

I've assemble tone with potensio 2x50K controll apex.
I heard the high voice is not good but if in a low voice I feel pretty catchy.
I question whether the components that I use have to be replaced?
help me Mr. APEX.
greeting
The following picture

 

[wattaniya]

anybody pls give the diagram of wiring the XLR base for amp speaker terminal.

 

[apexaudio]

I've assemble tone with potensio 2x50K controll apex.
I heard the high voice is not good but if in a low voice I feel pretty catchy.
I question whether the components that I use have to be replaced?
help me Mr. APEX.
greeting
The following picture

Use 1nF instead 3.3nF.
Regards

 

[QQ12e5k1]

Balanced Input

You can use this circuit with GND lift switch,
Regards

Do you have the copper side of this Balanced Input Sir???
In PDF..

Regards

 

[RSK]

Guitar amp

Miles,
I managed to put together the board for your 100W guitar amp.
Well almost completion.
Please advice, 2SK246 can be used insted 2N5638?

Thank you.......Raj

 

[nix]

ML3 Schematic

hi sir Apex how to add echo volume with your ML3..

regards,
nix

 

[DAMANHURI]

I do not get the echo effect for vocal sound. always based PT2399.
does anyone else?

 

[nix]

I do not get the echo effect for vocal sound. always based PT2399.
does anyone else?

this for microphone with echo volume if he have it possible additional parts or i.c. im waiting for the response of sir apex.

thanks in advance.

regards,
nix