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

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Whoops

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Hey guys. I've been trying to open the Harpo spreadsheet but no luck on page 55 theres one document with the excel and pdf extension..but fails to open..any other source available?

What do you need the spreadsheet for the "Pot center Tweaking" or the "Stepped switch calculator"?
 

ENS Audio

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Does anyone have the parts list and know where to order the correct pots and switches for this project? Thanks in advance!
 

Whoops

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Does anyone have the parts list and know where to order the correct pots and switches for this project? Thanks in advance!

All that info is in this thread, you will need to read the thread to be able to complete this project there's no shortcut.

The only Pots source with center detents is Audio Maintenance,
switches have no particular requirement you can get them from any store

Parts list attached
 

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  • Nite_EQ_Parts_-_fIXED.xls.zip
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steves.mastering

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Hi all, after moving house im finally digging this out of storage, its been half finished for years and now im trying to remember where i was up to.
i also used the 3D-EQ_PotTweaking_2 spreadsheet to calculate the ladder of resistors for the rotary switches.
From what i remember, the values should go from 44k through to 100k.
However, the values i get are wayy higher... up to 866k, is this correct?
I plan on doing the usual.. -5 to +5dB using 11 positions of a 1x12 lorlin.
1650093397854.png

Cheers,
 

Harpo

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Hi all, after moving house im finally digging this out of storage, its been half finished for years and now im trying to remember where i was up to.
i also used the 3D-EQ_PotTweaking_2 spreadsheet to calculate the ladder of resistors for the rotary switches.
From what i remember, the values should go from 44k through to 100k.
However, the values i get are wayy higher... up to 866k, is this correct?
I plan on doing the usual.. -5 to +5dB using 11 positions of a 1x12 lorlin.
View attachment 92827

Cheers,
...and 866,000 ohms in parallel with 113,000 ohms in the orange cell is 99,957 ohms, pretty close to the wanted 99,939 ohms on paper. The little drawing right next to the calc cells shows how to place this paralleled -not on pcb- resistor across the switch in order to make switching lesser jumpy.
 

steves.mastering

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...and 866,000 ohms in parallel with 113,000 ohms in the orange cell is 99,957 ohms, pretty close to the wanted 99,939 ohms on paper. The little drawing right next to the calc cells shows how to place this paralleled -not on pcb- resistor across the switch in order to make switching lesser jumpy.
Cheers Harpo.
Makes sense now. I bought all these resistors years ago. I just panicked when I saw 866K thinking I’d bought the wrong stuff. Makes sense again now 👍
 

ENS Audio

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Where can I order the 470k/500k Rev log pots from? If my memory serves me correct these have to be from a certain oem, no?
 
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