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Forum Home > Pedal Making Discussion. > ParaMix Mods

tonmann
Moderator
Posts: 1239

Here's a mod that adds a bit more flexability to the ParaMix.


I'm going to be adding a second effects loop, this time to the dry channel.  This will give you the normal dry and wet channels when nothing is plugged into this new loop or two wet channels when an effect is plugged in.  Although any two effects can now be used, my first thought was to use a compressor in this new loop to add a bit of tight clean signal to the distortion / fuzz in the other effects loop.



The above shows two methods of installing the loop, a post pot loop and a pre pot loop.  I would tend towards the upper diagram, the post pot loop, and probably use the lower diagram if the effect didn't have some sort of level / volume control.


The jacks used in this mod are mono jacks with a break switch connected to the tip, these are available from Mammoth Electronics.



I hope Blake doesn't mind me using Mammoth's photos as diagrams.


Notice that the Tip is closed against the Contact when a jack plug isn't inserted, once a jack plug is inserted the connection breaks.  From the first diagram, the signal goes to the Tip of the Send jack, through the Contact of the Send jack, through the Contact of the Return jack, through the Tip of the Return jack an onwards to the mixing stage.  By inserting jack plugs the connection between Tips and Contacts is broken and the signal is routed through the effect.


A point to note is that the price of these sockets is usually the same as jacks without switches - since I buy in bulk, I always order these jacks whether I need the switch or not.

It is possible to use to mono jacks without switches, but that would mean using a small patch cable when the loop is not in use.


The wiring diagrams for both types of loop:




The only technical problem I can foresee is one of popping when the effect is this loop is switched from bypass to effects mode (notice that you now have the original wet channel and a new dry / wet channel).  If popping should occur a 1MΩ resistor between the Tip and Sleeve of the Return jack ( for the post pot loop) or a 100kΩ resistor between the Tip and Sleeve of the Send  jack (for the pre pot loop) should do the trick.

January 23, 2012 at 7:50 AM Flag Quote & Reply

p_wats
Member
Posts: 37

Woah! Great timing, as I'm still working on the first of my 2 Paramix boards. 


I haven't had my coffee this morning, so maybe a bit of a dumbed down explanation is in order: this allows 2 separate loops? I assume the second one has no separate bypass stomp (ie, keep your compressor on in loop 2 while turning the fuzz off in loop 1), unless we mod it for one (though the overall effect bypass will still work, so I guess you could stomp off loop 1 and use the main bypass to stomp loop 2 on/off)? 


Sorry if this sounds silly...I'm just excited to try it! Thanks for all your suggestions/mods for this circuit!

--

Dog Is Blue - Toronto Based Ghost-Folk Duo

January 23, 2012 at 10:16 AM Flag Quote & Reply

tonmann
Moderator
Posts: 1239

I've decided to break this mod into two posts to keep it readable.


With this "second loop" mod added we are going to start running into real estate problems . six jacks, three knobs, a phase switch and at least one footswitch plus LED, it is going to be a tight fit trying to get everything into something like a BB enclosure.  Here are some thoughts on how to get rid of some of the off-board clutter.


Remove the Dry Gain Pot P1 -  this pot does have some uses but it would be the first pot to go, especially if the Post Pot Insert were used.  Put a jumper between pads 1 and 2 of P1 and increase the value of R5 to give a fixed amount of gain, the dry signal level is then controlled by P3 alone.  How much signal level you need is a matter of playing style and preference - since I require unity gain or better I would set P3 to about 20% rotation and then increase R5 until I had unity gain (marking unity gain on the enclosure once I had finished adjusting).


Replace the original SND and RTN mono jacks with a stereo jack.  In order to do this you will need one of these:



An insert cable from the good old days of analog mixing desks.  A stereo jack plug which splits into two mono jack plugs, the stereo Tip is used to send the signal to an effect, the Ring is used for the return signal back to the board.  This insert cable can be bought at most audio shops or you could make one yourself.


Wiring the SND and RTN jack is quite simple:



The "insert" mod uses mono jacks that have a switchable contact connected to the tip (see my previous post).  Instead of using two mono jacks you could use a stereo jack that has a tip contact and a ring contact.  Small Bear carries a stereo jack with two contact switches and their stereo jack with isolated DPDT switch which will also do the job.  Remeber you will still need a stereo insert cable when using these jacks.


The wiring for a stereo jack with switchable contacts:



Appologies for the stereo jack graphic, but the wiring to the lugs should be quite clear.


The stereo jack with the isolated DPDT switch is slightly harder as there are nine pins on the back of the jack.  I will happily trace out the connections upon request.


January 23, 2012 at 10:31 AM Flag Quote & Reply

tonmann
Moderator
Posts: 1239

Ah beaten before I could get my second post in !!!!!


To save any "loop" confusion, let's call the original loop the EFFECTS LOOP and the new mod the INSERT LOOP.


If you put a fuzz in the Effects Loop and a chorus in the Insert Loop and you install the Kill Switch, you can have:


Kill Switch off and both pedals in effects mode - a mix of the fuzz signal and the chorus signal.


Kill Switch on, fuzz in bypass or effects mode and the chorus in effects mode - just the chrous signal


Kill Switch off, fuzz pedal in bypass mode, chorus pedal in effects mode - a mix of a clean signal (from the Effects loops) and a chorus signal (from the Insert loop)


Kill Switch off, fuzz in effects mode and chorus in bypass mode - a mix of a fuzz signal (from the Effects loop) and a clean signal (from the Insert loop)


Kill Switch off and both pedals in bypass mode - a mix of two clean signals (depending on the phase switch setting).


Kill Switch on, fuzz in bypass or effects mode and the chorus in bypass mode - just the clean signal.  This would be very much the same as having the ParaMix in bypass mode except you can set the level of the signal to something other than you would have in ParaMix bypass mode.


Have your morning coffee and then read this again.

January 23, 2012 at 11:07 AM Flag Quote & Reply

p_wats
Member
Posts: 37

Thanks! Sorry for jumping in so quickly...the insert cables are a great idea! I've got some switching jacks kicking around I can experiment with. I'll hopefully have one of these built this week, so I can post my findings/photos.

--

Dog Is Blue - Toronto Based Ghost-Folk Duo

January 23, 2012 at 1:02 PM Flag Quote & Reply

draehn
Moderator
Posts: 579

"Good old days of analog mixing desks"

That's all I use! Does that define me as "good" and possibly "old"?

Or just mediocre and broke?

Please, don't answer that....

--

(o\  !  /o)

January 23, 2012 at 4:40 PM Flag Quote & Reply

p_wats
Member
Posts: 37

Should have mine done tonight! I'll have to build a few insert cables, as I've only got one and it's being used, you guessed it, in an analog mixing desk. Ha.

--

Dog Is Blue - Toronto Based Ghost-Folk Duo

January 24, 2012 at 11:50 AM Flag Quote & Reply

draehn
Moderator
Posts: 579

I think I saw a 10-pack of them on ebay this morning for around $16. 

My 32 x 4 board is about to be superceded by a digital desk and I want to keep it ready as a backup.  Hence the search for patch bays and the resultant cabling.

I used to have a procurement rating, so I tend to keep an eye out for prices on things...  Strange thing that.

--

(o\  !  /o)

January 24, 2012 at 12:09 PM Flag Quote & Reply

p_wats
Member
Posts: 37

I wired mine up last night. After troubleshooting a short (dead 47uf cap...always check your components first, kids!) I got it working somewhat. 


I assume the insert loop doesnt' mix with the dry signal like the effects loop does? Mine seems all or nothing. 

If that's the case then the dry signal and insert loop (using stereo switching jack and insert cable) seems to work fine, but I can't get any action out of the effect loop (using stereo jack and insert cable). 


Near as I can tell the dry signal and mix controls work fine, but the wet knob does nothing. I'm thinking the problem lies somewhere near the wet pot or send/return stereo jack. 

--

Dog Is Blue - Toronto Based Ghost-Folk Duo

January 25, 2012 at 10:57 AM Flag Quote & Reply

p_wats
Member
Posts: 37

I think I've got this all up and running... Now to figure out if I'll add the T-Diddy boost mod. My mind is boggling a bit thinking about how that stomp connects to P3 now that the stereo switching jack has been added for the extra loop. Is it possible to have both mods?

--

Dog Is Blue - Toronto Based Ghost-Folk Duo

January 26, 2012 at 12:01 AM Flag Quote & Reply

tonmann
Moderator
Posts: 1239

Your assumption is correct, whatever you have in the insert loop doesn't mix with the dry signal, it replaces the dry signal, obviously when you bypass the effect in the insert loop you will have the dry signal.


Adding the T-Diddy mod is not a problem, you connect an ON-OFF switch between lugs 2 and 3 of the pot..

January 26, 2012 at 12:46 AM Flag Quote & Reply

p_wats
Member
Posts: 37

Would this work? I've got the connection to Lug 2/Pad 2 of the dry level pot broken after the return of the effects loop. 
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Dog Is Blue - Toronto Based Ghost-Folk Duo

January 26, 2012 at 1:57 PM Flag Quote & Reply

tonmann
Moderator
Posts: 1239

In the up postion (middle to top switch contacts) you would have normal dry pot / insert loop function and normal wet pot function.


In the down position (middle to bottom contacts) you would have no signal from the dry pot / insert loop and 100% wet pot rotation i.e. boost.


It is not neccesary to run the ground wire to the bottom left hand lug.

January 26, 2012 at 2:41 PM Flag Quote & Reply

p_wats
Member
Posts: 37

Right, so the connection from lug 1 to pad 1 of the dry level is unnecessary? 


These mods just keep making this circuit more and more versatile (and necessary). I'll see how much real estate I've got for another pot in this enclosure and try to hammer this out tonight! 


I was having a great time last night with a tremolo in the insert and a fuzz in the effect loop! Thanks for all the help. 

--

Dog Is Blue - Toronto Based Ghost-Folk Duo

January 26, 2012 at 3:35 PM Flag Quote & Reply

Barry
Site Owner
Posts: 8793

Great Work Guys!

January 26, 2012 at 5:52 PM Flag Quote & Reply

tonmann
Moderator
Posts: 1239

Sorry, to the bottom left hand lug of the Switch

January 26, 2012 at 6:09 PM Flag Quote & Reply

p_wats
Member
Posts: 37

Ahh, got it! Thanks. I'll amend the drawing and repost it for other people to use if they want to really max out their Paramix. I'm about to add the boost stomp now...

--

Dog Is Blue - Toronto Based Ghost-Folk Duo

January 26, 2012 at 8:29 PM Flag Quote & Reply

p_wats
Member
Posts: 37

I edited the drawing and replaced the file, so the superfluous ground connection has been removed. I"ll post this in the main Paramix mods thread for anyone who wants to try it. 


I finally got mine all boxed up with 3 stomps (bypass, kill switch, boos mod) and both loops (using stereo jacks and homemade insert cables).  This thing is amazing! I haven't been this excited about a pedal for a long time, as the possibilities are endless---even my wife was impressed!


I'll create a build thread with pics/video next week. Thanks again for all the help.

--

Dog Is Blue - Toronto Based Ghost-Folk Duo

January 27, 2012 at 9:41 AM Flag Quote & Reply

Barry
Site Owner
Posts: 8793

Glad it all worked out and way to take it to the next level and Documenting it.


Thanks Tonmann for all the effort and Mod ideas!



Please feel free to contact me PWats and let me know whatever you get and I will post it in the Paramix Layout section.

January 27, 2012 at 4:32 PM Flag Quote & Reply

Kunfuz
Member
Posts: 8

Excellent info, thanks a lot!!

April 4, 2012 at 2:36 AM Flag Quote & Reply

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