Massive Active

[simonsez]

This beast eat me, even when it's not fully done yet...I hope he won't kill me when it's done.

 

[gyraf]

whoa!!

 

[rock soderstrom]

OMG!  ;D

 

[bruno2000]

Nice!
Best,
Bruno2000

 

[Corusco]

Switches for days! Love it. Those don't look like Igor's or Fabio's boards, unless I'm not looking at them right. Mind if I ask where you found them?

 

[simonsez]

Switches for days! Love it. Those don't look like Igor's or Fabio's boards, unless I'm not looking at them right. Mind if I ask where you found them?

I made that board  Integrating with ms-matrix and HPF/LPF

Peace!!

Simon

 

[shot]

Is it double sided board or single?
If it's single sided, any chance we can get a copy to self-etch?

 

[simonsez]

Is it double sided board or single?
If it's single sided, any chance we can get a copy to self-etch?

It's double sided through hole board, I think there were single layer board design by Fabio laying around.

Regards,

Simon

 

[frazzman]

Dang... I want in... Any prospect of this design being released ?

 

[leadbreath]

guys, come on lets get some sontec action going!!!

 

[dagoose]

nice!  8)
Keep us up to date! 

 

[Gustav]

Inspiring!

Gustav

 

[madriaanse]

Impressive! Very high KSI (knobs per square inch)!

M.

 

[simonsez]

Wiring done  , power up.....all voltage looks good, no smoke  , Will do some signal test tonight.... :-X

Peace!!

 

[Lamouette/rck]

Looks so goooood !

 

[simonsez]

- Trapped between Igor and Fabio value, must adjust a few component value  :
- Adjust the HPF/LPF to usable range for mastering purpose, i don't need 1Khz LPF or 300Hz HPF 
- Audio pass, parametric works great, Hi and low shelving works.

By the way, why Igor put a pair of 7k5 resistor below?

 

[helterbelter]

IIRC it halves the amount of boost/cut, so you have more precision.

But where did you get the schematic from ? I have built Igor's sontec, but I don't have the full schematic, only the docs Igor shared on his website.

 

[simonsez]

IIRC it halves the amount of boost/cut, so you have more precision.

But where did you get the schematic from ? I have built Igor's sontec, but I don't have the full schematic, only the docs Igor shared on his website.

Are you sure?.. I thought that was did by altering the feedback resistor (R67_AE)?
I forgot where I got the schematic, but i have the copies if you interesting.

 

[helterbelter]

The schematic : Cool, I'll send you a pm in a minute with my emailaddress. The low shelf isn't working properly, schematics would make a lot clear, I think.

Regarding the 7k5's : No, I'm not entirely sure, but copied from the BOM :
"8 7k5 R-EU_0204/7
'USE 4K7 FOR MORE BOOST/CUT; INSTALL ON BOTTOM SIDE OF FILTERS PCB ".

These are also the only 7k5 resistors in the BOM, so.....

 

[helterbelter]

Thanks for the schematic !

Now I see the complete picture, great !

Well, regarding changing the value of the resistor in the feedbackloop : yes, that can be done as well, but the method of the 7k5s on top and bottom of the gainpot works very well, possibly better than changing the feedbackresistor.

A bit off topic,
As a matter of fact, I once started modifying a graphic eq into an API560 (originally made by the brand 'Soundtech"...... Honestly !), I came to the conclusion that I had to put resistors on both the top and bottom of the sliders, otherwise the frequencies boosted by the different bands would start oscillating. But that's a bit off topic.