3D "AIR" EQ - "Night EQ" PCB's Complete!

[pstcho]

Hello there, are there any PCB left? 

thanks

 

[smokinpcb]

does anyone know what kind of pots are used in the new maag units?
the indents are super awesome

 

[Whoops]

does anyone know what kind of pots are used in the new maag units?
the indents are super awesome

that would be nice to know actually,
also the resistance at the center needs tight tolerances, so probably they have the pots custom made for them 

 

[Harpo]

does anyone know what kind of pots are used in the new maag units?
the indents are super awesome

Without knowing the context of the corresponding circuit behind (they might know better by now how to build it with a lot less hassle), this question is either irrelevant or at best of academical use. As always YMMV.

 

[smokinpcb]

I was more referring to brand over resistance value etc.
I have some friends that have the 500 series eq4's, if they are cool with me taking a look inside the units I'll post what I find!

 

[dirty1_1garry]

Hi folks!

I became interested on Night EQ. And before building it I've decide to emulate it.
For easier schematic understanding I've simplifying it (original schemaric was found it at the beginning of the thread) and made it more readable.
Here is what I've got:

For LTspice emulating I've emulate only one band - 40Hz. And here is what I've got:

As you can see, changing resistance of gain pot change only whole frequency range gain, not only one band. So what I'm doing wrong?)

 

[Whoops]

I think the way it works is all pots resistance affect all the frequencies, I think you can't change one pot resistance alone without compensating all the other pots resistance also.

Have you seen the excel document to calculate the change in resistors?

 

[peterc]

Remember as well, that these bands have VERY wide bandwidth.

So this might be the reason

Peter

 

[dirty1_1garry]

I think the way it works is all pots resistance affect all the frequencies, I think you can't change one pot resistance alone without compensating all the other pots resistance also.

Hmmm, will try!

Have you seen the excel document to calculate the change in resistors?

At what page I can find excel doc?

 

[Harpo]

Hi folks!

I became interested on Night EQ. And before building it I've decide to emulate it.
For easier schematic understanding I've simplifying it (original schemaric was found it at the beginning of the thread) and made it more readable.
Here is what I've got:
//snip

For LTspice emulating I've emulate only one band - 40Hz. And here is what I've got:
//snip
As you can see, changing resistance of gain pot change only whole frequency range gain, not only one band. So what I'm doing wrong?)

Looking at your dB numbers, your emulation schematic is missing the shunt arm resistor R24 from the voltage attenuator R25/R24.
As you can see, this "EQ" consists of a number of bandwidth limited non-inverting gain stages (not filters). Other than inverting gain stages or filters, these gain stages with 1st.order -6dB/oct. slopes stop falling when unity gain is archieved. You need all stages built exactly two octaves apart, so these summed up stages reconstruct the whole audible frequency band. The frequency and gain setting parts values shown in the schematic are only rough approximation numbers. What you perceive as cut is lesser boost and the max.archievable cut is set by prementioned attenuator.

 

[dirty1_1garry]

Looking at your dB numbers, your emulation schematic is missing the shunt arm resistor R24 from the voltage attenuator R25/R24.
As you can see, this "EQ" consists of a number of bandwidth limited non-inverting gain stages (not filters). Other than inverting gain stages or filters, these gain stages with 1st.order -6dB/oct. slopes stop falling when unity gain is archieved. You need all stages built exactly two octaves apart, so these summed up stages reconstruct the whole audible frequency band. The frequency and gain setting parts values shown in the schematic are only rough approximation numbers. What you perceive as cut is lesser boost and the max.archievable cut is set by prementioned attenuator.

Thanks for tips!
Here is what I've got with adding all stages. Emulation curves start to look more real
SUB band curve with 250K 100K 70K 50K 40K 30K 20K 15K gain resistor, all other are 40K (close to flat position).
When gain res = 500K or 250K curve changes just a little bit. When gain res = 1R (max gain) sub bell rise up to +14dB but with +6dB on all other range. So range from 250K to 15K looks more useful for me.

 

[dirty1_1garry]

Any experience with rev log pot? What relation of pot turn angle with resistive of rev log pot?

 

[Whoops]

Hmmm, will try!

At what page I can find excel doc?

page 41 of this thread,
check my post

 

[dirty1_1garry]

page 41 of this thread,
check my post

Yeah, got it, thanks! Found a lot of interesting info here. For example, that was really interesting to see your eq curves. Mine pretty close to yours)
Absolutely not a universal eq, but of course that's no matter if it do the right job)
Here is what I've got again:





But I've found one confusion fact - when I boost only one freq up to 5dB, all freq range boost at about 1-1.5dB, so total boost of one freq above all range  became  around 4dB. But when I boost two freq, for example 40 and 2500 here is what I've got:


So it looks like gain compensation  pot would be pretty useful here.

 

[dirty1_1garry]

Haha, found a video that shown a curves of EQ4 plug-in. It gives the same bump(from 3 to 6dB) on all freq range when you boost only one band. That gives a small confirmation to my emulations

https://www.youtube.com/watch?v=lFS1bhaM-SM

 

[febo2609]

Does anybody  have PCB etching files so I can make my own?  PDF/gerber?

Thanks

 

[Whoops]

There's a lot of unused pcb's around members,
post in the black market asking to buy some

 

[MarcOliver]

Hello Peeps!

Im fairly new on this forum, my name is Marc Oliver, a UK based engineer.

I am looking to purchase two Nite EQ3D boards, any chance someone has a pair out the back? otherwise i will have to have them made to order, which will cost me an arm and a leg.


Thank you

Marc

 

[Whoops]

Hello Peeps!

Im fairly new on this forum, my name is Marc Oliver, a UK based engineer.

I am looking to purchase two Nite EQ3D boards, any chance someone has a pair out the back? otherwise i will have to have them made to order, which will cost me an arm and a leg.


Thank you

Marc

Hi Marc,
search in the Black Market section ,
and also Post a "WTB" there. There are a lot of these pcb's in drawers

 

[fazeka]

Hey all,

I have a dead original Nightpro unit from the late 90s. I suspect it has corroded traces, some bad enough to cause a channel not to work. I think it's bad enough to where stopping the corrosion is too late... so thinking about having these PCBs cloned, wondering if anyone could help? I would like to have these cloned to use with the original pots and switches (and their positions, that line up with the front panel) of the original. Also, the footprint of the power supply and the interconnect between the two boards would mean it would be a simple drop in replacement into original cases. And I get to use the original switched mode power supply...

But I may be just dreaming at this point... 

If anyone can assist with this, please PM me. Thanks.

Otherwise, Peter, if you are reading this, do you happen to have an extra pair of PCBs lying around?  ???