ABDUCTOR II Delay meets Dimension P Chorus - where are the PT2399 Experts?

[Mr. Lime]

I have an Abductor Delay PCB from Deadastronaut laying around (great project, thanks Rob!) and thought about the Dimension P chorus and how to implement it on the PCB.
Basically both are PT2399 circuits and only differ in the pin layout where the LFO goes in.
The lower PT2399 chips are in parallel and form the chorus part. In the original Dimension P circuit the feedback resistors from the LPF gain stages of the chips are much higher. Is there anything critical wrong with the new values?
The chorus is driven by the orignal LFO while the delay gets it's own TapTempo control. This is quite a big PCB and before I start I'd like to have an educated view from someone who's more into PT2399 circuits then me 
What do you guys think?


Thanks in advance!



Original schematics:
https://docs.wixstatic.com/ugd/ff4c6c_fcc25b7c4e2b477cb64afe89707bc2ff.pdf
https://sites.google.com/site/distorque/_/rsrc/1320504569305/home/projects/pictures/Dimension%20P%201-1%20small.png

[samhay]

If you turn the delay length and feedback down to minimum, you will get a chorus-ish effect.
IIRC, the Dimension P splits and inverts the LFO, sending these phase-opposite outputs to each PT2399. This will be difficult to achieve using the PCB you have.

[Mr. Lime]

If you turn the delay length and feedback down to minimum, you will get a chorus-ish effect.
IIRC, the Dimension P splits and inverts the LFO, sending these phase-opposite outputs to each PT2399. This will be difficult to achieve using the PCB you have.

I know that chorus-alike sounds can be archived with the Abductor as it is but the Dimension P is said to be really great..
Of course there is a lot to rewire and some offboard wiring like the additional inverter. I probably have to put 2 PT2399 on vero and wire the pins differently to the board.

[deadastronaut]

gonna need a bigger boat....

heres distorques 'dimension p' site, schemo etc..and clips, just for reference...

http://distorqueaudio.com/hardware/projects/dimension-p.html

[bluebunny]

TBH, I'd just keep Rob's fantastic Abductor for what it is and do the Dimension-P separately (which is also fantastic - built three).  I think it would be too much faffing to hack Rob's board to be something else.  If you're interested, I did a Vero layout.  It's not the prettiest or the smallest, but it's verified (three times!), and it's yours if you want it.

[samhay]

Or to muddy the water, I will soon be releasing a 2 PT2399 beast that can do parallel delay lines modulated with out-of-phase LFO...

[bluebunny]

Muddy away, Sam...   

[deadastronaut]

yep, lob that mud about....

[samhay]

I need to finish building it properly before unleashing it on the wild. Shouldn't be long now that the weather has turned.

In the mean time - OP: as others have said, you are almost certainly better off building the Abductor and then something else as a dedicated chorus. Personally, I would choose a BBD chorus over a PT2399, but I appreciate this is a little more complicated.

[Mr. Lime]

I need to finish building it properly before unleashing it on the wild. Shouldn't be long now that the weather has turned.

In the mean time - OP: as others have said, you are almost certainly better off building the Abductor and then something else as a dedicated chorus. Personally, I would choose a BBD chorus over a PT2399, but I appreciate this is a little more complicated.

Actually I already built several pedals including a deluxe memory man delay and a BYOC mega chorus, both BBD. It's more about to do something different or bring my own ideas in..
I also thought about the Dimension C chorus but really don't need another stock pedal. I assume that there's nothing critical wrong with the circuit above?
The changes on the PCB are minimal.

[samhay]

In that case, I suggest you draw up a schematic showing your proposed mods to the Abductor.
Happy to give you some pointers. Thinking about it in terms of daughter boards, etc, is only half the job and you might find you can get away with easily re-routing quite a lot on the existing board.

[Mr. Lime]

Good advice, thanks! 

I redraw the schematic on the first post and used the component numbers from the PCB/Abductor schematic. I also gave comments on changes and new tracks and where to place them best.
Should be way easier now to comprehend my intentions! 


The only thing what could be unpredictable for me are the resistor values for the internal gain stages to mix the signals well.
Any advice on this or can I leave it as it is? (R13, R11, R14, R15, R47, R48)

[samhay]

I don't see anything in the new schematic that obviously won't work.
Impedances seem to be about right and I don't see any problems with DC coupling, etc.

There are a little of filter values, etc, that Rob will have tweaked by ear. If you are going to go to the bother of building this, I would do so first on the breadboard so you can check it works as expected and then take some time tweaking to taste.