# modding the informant... input needed :-)



## jcrews (Apr 20, 2021)

built a few of these stock.  like the sounds.  attempting a relay switched soft touch version like the real deal this weekend.  
I'm considering making one in a larger 1590bb with some mods.  Here's what I'm thinking, and I'd be down for any feedback or knowledge.

1.) diode clipping on a switch (i have this figured out and tested.  Likely go 1n914(stock)/red LED or GERM/SILICON/LED if i can figure out how to do three(im assuming an ON ON ON DPDT instead of ON ON?  diagram below
2.) buffer on a switch (pedal PCB staff hooked me up with a diagram for this and i successfully added it to a stock build already, HOWEVER.  I'm going to be trying it again with a relay switched board and may need help.  Someone shared the layout for using the buffer with the relay, and i have the layout for it on a switch in standard 3pdt wiring....just need to marry the two if it's possible.
3.)  Ruetz mod?  Is it possible?  I really liked this on my old rat builds.  Adds in the lows and cuts gain.  In a rat it's as simple as putting the 47ohm resistor coming off the IC chip leg on a switch.  I'm less familiar with this circuit and don't see a resistor in the same place, nor does the value match anything in the schematic.  Might not be possible at all, but if the results are anywhere near the same as they are in a standard rat circuit it would be neat to have.  Almost like a distortion/overdrive switch......  

Maybe I'm grasping at straws.  Such a good circuit on it's own but I can't help but want bells and whistles just for grins.


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## fig (Apr 20, 2021)

jcrews said:


> 1.) diode clipping on a switch (i have this figured out and tested. Likely go 1n914(stock)/red LED or GERM/SILICON/LED if i can figure out how to do three(im assuming an ON ON ON DPDT instead of ON ON? diagram below


Something like this?

https://guitarpcb.com/wp-content/uploads/2018/06/The-AMAZING-ROTO-TONE-DELUXE-Final.pdf


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## jcrews (Apr 20, 2021)

fig said:


> Something like this?
> 
> https://guitarpcb.com/wp-content/uploads/2018/06/The-AMAZING-ROTO-TONE-DELUXE-Final.pdf


that is wild.... I'll consider it if there's room.  I have something similar in a rat build from way back in the day.

from my understanding with the diagram i have (on/on DPDT on/on with diodes on each end) I can use an ON/ON/ON wired the exact same with diodes in the middle, just need to verify that the wires running to D1 on my PCB are correct.

This image explaining the poles has only served to muddy the waters.


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## manfesto (Apr 20, 2021)

You wouldn't want to use an on/on/on switch for this.

There are two ways to go:

1. Use an on/off/on DPDT switch connected to D1 or D2, strap antiparallel 1N914s across the top lugs, antiparallel LEDs across the middle lugs, and antiparallel germaniums across the bottom lugs.

That'll give you silicon or germanium in the up and down positions, and LED in the middle. A little tight on space though.

2. Use an on/off/on DPDT switch connected to D1, strap antiparallel 1N914s across the top lugs, antiparallel germaniums across the bottom lugs, and then put antiparallel LEDs in D2.

Functionally, this is the same - silicon and germanium in the up and down positions, LED in the middle - but it's less tight.


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## manfesto (Apr 20, 2021)

As for the Ruetz mod, I guess you could do something kinda similar if you replace R8 with like a 1K pot? It may not sound or do quite the same thing (the stock Rat has two parallel RC networks forming two overlapping high-pass filters, the Informant only has one and it's tuned pretty differently)


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## phi1 (Apr 20, 2021)

In my build, I added a 1k pot in series between R8 and C5. That way you have a resistance range of 470ohms to 1.47kohms.  5k or 10k pot would give this more range.

it’s not the reutz mod exactly, but works well to adjust the voice. Kinda more like a zendrive voice knob. 

the rat has two RC networks in that area where the drv has one.
Rat: 
47R & 2u2 - cuts lows below 1.5kHz
470R & 5u6 - cuts lows below 60Hz
DRV:
470R & 220n - cuts lows below 1.5kHz

Ok so the DRV only has the 1.5kHz path of the rat. BUT, the R also inversely affects the gain. So wait, the gain of the DRV in this stage is 10x less? Oh right, because the DRV has a boost stage in front. I believe the designers inspiration was a boost into a rat set with low gain.

so if you wanted an equivalent to the rat reutz mod, you could add another RC path with scaled values (4.7kohm & 560n, cut off at 60Hz). Then the reutz mod would switch off the 470R & 220n path.

however, there’s enough other sonic differences between the rat and drv circuit, that I don’t know as it’s worth trying to replicate the rat reutz mod in detail, up to you though. The voice knob in series like I did should get you some less aggressive tones you’re after, especially if you go up to 5k or 10k.

another cool option is a bass knob in this area. Can provide details if that sounds interesting.


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## jcrews (Apr 20, 2021)

Thanks for clearing up the diode switch.  Can I still pull it off with antiparallel 1n914's across the middle, germie's on the bottom, Led's on the top (leaving the middle stock)?  room shouldn't be an issue. (hopefully)
Same leads running to D1 from from the middle two lugs like i posted (the ones in the instance holding the two 1n914's)?

I have a gaggle of LED's, and 1N914's, no germanium diodes.  What would be a good choice for this slot?

As far as the Ruetz goes..... I was hoping it would work out, but I just couldn't see any similarities to that part of the circuit.  Worst case I can only have my two weird switches.  I'll get out the alligator clips and see whats what with R8.

yall are the best.

If i can just figure out how to retain the buffer bypass and wire up the latching relay..... I'll be right as rain.


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## jcrews (Apr 20, 2021)

phi1 said:


> In my build, I added a 1k pot in series between R8 and C5. That way you have a resistance range of 470ohms to 1.47kohms.  5k or 10k pot would give this more range.
> 
> it’s not the reutz mod exactly, but works well to adjust the voice. Kinda more like a zendrive voice knob.
> 
> ...


Well it seems like the traditional Ruetz is out.  Not into adding a new RC path just to clip bits of it out for fun.
voice might be cool and I have enough from this to try it out and see how it sounds.

I'm down to hear about the bass knob.  I'll have a little space then i anticipated if one of the clipping switches is a no go.

I like the sounds enough just stock that i want to make sure I'm just adding options and not taking anything away.  So i don't want to get too far from the OG layout, but little things like clipping or cutting the output down to something.... I'm into that.

the bass knob could be really usefull like it is on a nobels, i would just want to make sure (like the nobels) in one position or the other I'm still capable of stock DRV sounds.


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## phi1 (Apr 20, 2021)

For the bass knob I’d follow the Timmy type configuration. 

At the connection between R8 and C5, branch off to a 25kB pot lug3. lug2 to 4u7 cap, to ground. This gives you another path to ground, with bass frequencies (down to 72Hz). The pot inversely controls the gain level of this bassier path. Another way of thinking of it, the pot gradually ‘brings in’ the larger cap. you can mess with the cap value, for example 1uF will give you less intense bass with the knob maxed. 


because of the way the R and C in this area affect bass frequency and gain, it’s a popular area for mods. For example, see the eqd palisades schematic. Different Cs for all the different voices.


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## jcrews (Apr 20, 2021)

that's cool, and super informative.  I love the same mod in some of my other drives, so i might have to try this.  

Also considering a "no diodes" area of the switch as well.   That might handle my "less grit" desire for the ruetz mod.  
Assuming this would just need a ON/ON/ON with 1n9124's on one end, LED's on the other?  Sorry for all the noob stuff.  I'm still learning...


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## jcrews (Apr 22, 2021)

I've got everything wired up and ready to box and test.  I'm hoping someone has a clever solution to retain my ON/OFF switch for the buffered bypass  This layout:



the user Manfesto hooked me up with a layout for the buffered bypass to the relay 
1. connect your 1/4” input jack to the “IN” pad on the Informant board
2. connect the “BP” pad on the Informant board to the “JACK IN” pad on the bypass board
3. connect these - “GND”, “SW”, “OUT”, and “JACK OUT” - as normal.


I'm trying to retain the switchable functionality for running it earlier in my chain before germanium stuff.

I understand why this works both ways but im not sure how combine the two.  the dpdt has too much stuff going back to the switch


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## jcrews (May 1, 2021)

UPDATES:

I finally threw in the towel on trying to figure out how to incorporate the "switchable" buffer on my relay switching versions....
Couldn't decide on the buffer or not so..... I just did them both.  Bigger dude has the "stock" soft touch switch and buffered bypass
The little fella has buffered true bypass.

Both of them have my clipping mod.  Can't say enough good things about the clipping.  I LOVE the LED's vs the diodes and the NONE setting in the middle sounds great as a clean boost with the DRV down, and also great with just op amp clipping as you go up the DRV knob range.  Really great sound.  the LED mode is louder and the NONE mode is WAY louder.  

I feel like they really nailed this circuit and these tiny clipping mods really worked well to give it a little more dynamic range.  It will do more for me now, so I'll use it more.  

Anyhow thanks to the brain trust here.  These were my very first ever relay'd bypass builds with the soft touch.  They won't be my last.  It's a pain and extra work but it really makes a pedal feel premium.  I won't use it always but I am already eyeing a new loop switcher built around these.  

Thanks again for all the patient explaining to a noob.


Y'all are the best.


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