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I think there would be more changes than just the eq on the bass version.

May I ask what language did you write the tilt eq in? I'm learning html5 along with c#, python and a couple others.

Anybody still care?

absolutely ! yes we do !

crackerman, do you still have the pedal ? could you find the value of the electrolytic that is sandwiched on the lower left corner in between the 104, 821 and 101 poly caps (according to my pic with the values that i posted in the first post on page 1) ? that one should be C15 according wk´s schematic, and is bigger than the 330n that is used in the guitar version.

thanx

power section. working on the other parts of the circuit.
i used whitekeyhole´s schemo as a basis, hope that is ok.

input and comp stage. value of C15 yet unknown, something that still makes me scratch my head in the lower rigt corner of the schemo, but this is what i have so far. values in red mean it´s changed from the guitar vrsion, values in black means they are the same.

the eq section seems to be identical, except two 15n caps can be switched in in parallel, the value of the caps which remain in the circuit all the time (C5 and C4 on wk´s schemo) is unfortunately unknown yet. the only polys i did not get a reading for, can´t remember why...it is the two caps above the big fat 100n poly marked 104G on my pic. the only other difference i can see so far is that instead of the 330n, an 4µ7 electro is in parallel with the 820p both going into the eq section (C6) and to the output (C8).

ok, judging from my pics i am 99% sure that C15 is 4µ7.

ok, we need to find out the values of these two buggers:

lohstah wrote:ok, we need to find out the values of these two buggers:

those two buggers.jpg

If you read my post you can see that the total capacitance needed to get a center frequency of 250Hz is 20nF. The ideal value for C4 and C5 is 5nF, so they problably are 5.6nF like the guitar version

472J 4.7nF

I would love to fix my attempt at copying this. One of the side chain outputs oscillates and I can't figure out why.

Power Section Revised. the 1N4004 is actually in series between C1 and C2, dropping roughly .7V i suppose. the diode across the power rails looks like a 1N4148.

Input and Optocoupler Stage. C26 and R31 are in reversed order.
R20 is hard to make out, R33 too.

EQ Output and LED stages. R6 and R37 hard to determine.

so, the last 4 question marks are the values of R6, R20, R33, R37.
maybe crackerman can have a look for us ? i marked them with green circles on the pic below so they are easy to find.

Top left: 100
Bottom left: 6.81K
Top right: 6.81K
Bottom right: 150K

the final schemo for the moment...values corrected by crackerman are in green.
i´m having doubts about R37. other than that, should be good to go. now somebody build it and confirm

I did find a few things when I traced through this.
-There is a 1M resistor to Ground between C15 and R25
-C26 and R31 need swapped. The coupling caps tie together and the opamp is an in an Inverting configuration.
-On pin 2 of IC1A(LM358) there is a 100K resistor which goes to a .1u cap to Ground. Non-inverting circuit

I also tried to further investigate R37. It's: Brown Black Black Black Brown. It reads around 100 in circuit.