The No.1 Website for Pro Audio
 Search This Thread  Search This Forum  Search Reviews  Search Gear Database  Search Gear for sale  Search Gearslutz Go Advanced
Behringer Model D - DIY Mods
Old 1 week ago
  #1
Gear Head
 

Thread Starter
Behringer Model D - DIY Mods

Hey,

Have any Boog owners started poking around in their D for expanding connectivity? Haven't found any posts on this, so here we go...

Just opened my boog and started tapping some points I'm interested in wiring up for Eurorack use. Found some easy ones straight away, which I'll describe below, but hopefully others want to chime in

Pitch CV - the easiest seems to be Pitch VC out to use the Boog as a full Midi CV interface (with the two envelope outs in lieu of gate out). It's in the manual and clearly labelled as a TP for calibration. This one to tip and ground to sleeve, and you are good to go.

VCO Waveforms - tapped from the rotary selector. I labelled tri, saw and square in the pic below. Waveforms/pitch stay stable when tapped, but buffering might be a good idea for a permament mod.

White/ pink noise out - tapped from the selector switch pre volume poti.

Somewhat shank pics below - redundantly labelled "CV Pitch" (in case you can't read the white "Pitch CV" and didn't have a better marker colour at hand (but red's more organic and warm than blue or black anyways, right?


Implementing sockets should be easy - best option to me seems using the side panel, i.e. take off the wood & drill holes into the metal side/ replace the whole side with something you want to drill holes in. If you use the boog in a Euro case it's even easier.

If you have found further mods, bring em on!
Attached Thumbnails
Behringer Model D - DIY Mods-dscn3447.jpg   Behringer Model D - DIY Mods-dscn3448.jpg   Behringer Model D - DIY Mods-dscn3449.jpg  
Old 1 week ago
  #2
Gear Head
 

Thread Starter
...and on we go (long live procrastination)

Detune VCO 2/3 - right lug of detune pots for selective vibrato/fm

Selected wave outs - outputs the waves of vco 1-3 as selected by rotary switch. this is before osc level, i.e. signal is full even if level pot/switch are not

Hi pass out & low pass out - tapped from lp/hp selector switch

Filter section generally wants to be handled with care. and so does the rest, of course, as this is based on experimental tinkering. In general my impression is that the Boog handles the latter quite well.
Attached Thumbnails
Behringer Model D - DIY Mods-dscn3453.jpg  

Last edited by Maffez; 1 week ago at 08:10 PM.. Reason: corrections
Old 1 week ago
  #3
ear nut
 

Nice thread idea!
Old 1 week ago
  #4
Lives for gear
 
Derp's Avatar
I'm excited to see how this develops as I love my Boog. If someone can come up with a mod to give individual CV control to each oscillator, direct oscillator outputs, give us an external input that bypasses the mixer section, and have a filter out that bypasses the VCA, that person will be a hero!
Old 1 week ago
  #5
Gear Head
 

Thread Starter
yo, a bit more...

@Derp - except for individual cv control of the vco's all boxes ticked

individual direct vco outs can be had at the waveform selectors, i.e you can even tap all waveforms simultaneously to have some roland sh/akai vx style thing going on. Signal flow in the boog is vco out, volume pot, switch, which means you could also decouple the mixer section entirely

as for the vcf / vca section - most of that can be handled via the vcf mode (lp/hp) switch. at the pic below lp out (pre vca) and hp out (pre vca) are labelled; hp signal, owever, is only present if the switch is set to hp. the switch out (labelled "to vca" below) can be decoupled with a switch or a switched socket if desired. the trimmer left to it (white label vcf hp), in turn, is ace for post mixer out (lug on "HP" end upper right is hotter than bottom lug)

also did a bit of tinkering with the vco 2/3 tune pots - my multimeter skills are sh...t but they seem be 5k linear, just as specified in the original minimoog service manual; higher values give you a greater span (10k works quite nicely as it retains the lowest value but extends highest pitch to over an octave)

adressing the vco pitch cvs individually does not make much sense in my setup, but I'm sure it won't be too hard for someone who knows how to read schematics & volt meters?
Attached Thumbnails
Behringer Model D - DIY Mods-4.jpg   Behringer Model D - DIY Mods-5.jpg  
Old 1 week ago
  #6
Lives for gear
 
Derp's Avatar
Thanks for the info. Now I just need to find a modder I can pay to this for me so I don't destroy the whole thing building a new patchbay for it.
Old 1 week ago
  #7
Gear Head
 

Thread Starter
Yes! And pictures should you get it done.
Old 6 days ago
  #8
Quote:
Originally Posted by Derp View Post
Thanks for the info. Now I just need to find a modder I can pay to this for me so I don't destroy the whole thing building a new patchbay for it.
I’d ask @Septik. Or the MillionMachineMarch guy, I forgot his GS moniker.
Old 6 days ago
  #9
Lives for gear
 

I would love to tap the final filter CV after the key tracking, envelope, contour amount, mod, etc. it would also be nice to be able to override the the vca in with a signal in (post filter).

Basically making it easy to take an external filter module and have it fully functional as if it were built into the unit. That would be amazing.
Old 6 days ago
  #10
Gear Head
 

Thread Starter
Quote:
Originally Posted by Vertflyer View Post
I would love to tap the final filter CV after the key tracking, envelope, contour amount, mod, etc. it would also be nice to be able to override the the vca in with a signal in (post filter).

Basically making it easy to take an external filter module and have it fully functional as if it were built into the unit. That would be amazing.
Shouldn't be too tricky. You can tap the sum of filter cvs at the input of VR10 (the filter calibration trimmer). Your sum of vco's goes from the mix out socket into the external filter, and the output of that filter into the bottom middle lug of the filter switch (which you'd preferrably decouple by means of a switched socket, i.e. external input plugged in disconnects boog's vcf to vca).


Also, just noticed that the boog's schematics are posted in another thread ...
Old 6 days ago
  #11
Lives for gear
 
Moonwhistle's Avatar
 

Quote:
Originally Posted by slaughtrhaus View Post
I’d ask @Septik. Or the MillionMachineMarch guy, I forgot his GS moniker.
DSC unless I'm mistaken.
Old 6 days ago
  #12
Lives for gear
 

Quote:
Originally Posted by Maffez View Post
Shouldn't be too tricky. You can tap the sum of filter cvs at the input of VR10 (the filter calibration trimmer). Your sum of vco's goes from the mix out socket into the external filter, and the output of that filter into the bottom middle lug of the filter switch (which you'd preferrably decouple by means of a switched socket, i.e. external input plugged in disconnects boog's vcf to vca).


Also, just noticed that the boog's schematics are posted in another thread ...
Thanks! I think I may try this over the weekend!

Which filter switch are you referring to? The hi lo switch?

Also which thread has the schematics?
Old 6 days ago
  #13
Gear Head
 

Thread Starter
Quote:
Originally Posted by Vertflyer View Post
Thanks! I think I may try this over the weekend!

Which filter switch are you referring to? The hi lo switch?

Also which thread has the schematics?
hey, cool, & keep me posted on your results if you do

yes, hi/lo switch - see labelled pics above for the pinout on the backside

schematic is here: https://www.gearslutz.com/board/atta...3-09_rev.0.pdf

cheers
Old 5 days ago
  #14
Lives for gear
 

Quote:
Originally Posted by Maffez View Post
hey, cool, & keep me posted on your results if you do

yes, hi/lo switch - see labelled pics above for the pinout on the backside

schematic is here: https://www.gearslutz.com/board/atta...3-09_rev.0.pdf

cheers
Maffez,

Have you investigated the jacks from the component side of the board? Are there traces on that side? The solder side of the jacks clearly do not have the traces. I’m worried the pcb has layers in the middle?

Main reason, I want to use some of the jacks as the total filter cv out and post filter vca in. Also, can you tell if the jacks are normal capable jacks? They have 4 solder points each.

If so I would like the make one of the jacks normalled to the hi pass filter out, then have it cut over to the post filter audio in when it is plugged in.
Old 5 days ago
  #15
Gear Head
 

Thread Starter
Quote:
Originally Posted by Vertflyer View Post
Maffez,

Have you investigated the jacks from the component side of the board? Are there traces on that side? The solder side of the jacks clearly do not have the traces. I’m worried the pcb has layers in the middle?

Main reason, I want to use some of the jacks as the total filter cv out and post filter vca in. Also, can you tell if the jacks are normal capable jacks? They have 4 solder points each.

If so I would like the make one of the jacks normalled to the hi pass filter out, then have it cut over to the post filter audio in when it is plugged in.
Hey,

jacks seem all to be tip/sleeve, with two additional solder points for stability. The switches and pots are similar (two thicker pins for stable physical connection).

You can also google for high res pics of the board or just investigate on your own. Don't think there is a middle layer on the pcb.

as for the hp out/vca in you have in mind, i've not completely wrapped my mind around this (which is a little hungover today.. - the filter mode switch is double pole double throw, with boths rows serving different purposes. one row selecting between lp/hp to vca and the other row engaging the hp (as mentioned hp signal is only active when the switch is set to hp, while lp is present irrespective of the switch's position) - need to check on this a little further. as regards the vca in, I'm positive, however, which would be the place for a normalled jack for post filter vca in.

happy to post future updates on this
Old 4 days ago
  #16
Lives for gear
 

Great thread. Thanks for sharing.
Old 4 days ago
  #17
Lives for gear
 

Quote:
Originally Posted by Maffez View Post
Hey,

jacks seem all to be tip/sleeve, with two additional solder points for stability. The switches and pots are similar (two thicker pins for stable physical connection).

You can also google for high res pics of the board or just investigate on your own. Don't think there is a middle layer on the pcb.

as for the hp out/vca in you have in mind, i've not completely wrapped my mind around this (which is a little hungover today.. - the filter mode switch is double pole double throw, with boths rows serving different purposes. one row selecting between lp/hp to vca and the other row engaging the hp (as mentioned hp signal is only active when the switch is set to hp, while lp is present irrespective of the switch's position) - need to check on this a little further. as regards the vca in, I'm positive, however, which would be the place for a normalled jack for post filter vca in.

happy to post future updates on this
Did some investigating today. Bottom line I’m at a loss for tapping out a total filter cv. I’m no electronics expert but my dad helped me look and this is what he said.

The inputs at the vcf scale trim only has current mixed from the various vcf sources. The voltage measured at that point is millivolts.

If anyone else has any ideas of what to try or measure I’ll give it a shot.
Old 4 days ago
  #18
Gear Head
 

Thread Starter
Quote:
Originally Posted by Vertflyer View Post
Did some investigating today. Bottom line I’m at a loss for tapping out a total filter cv. I’m no electronics expert but my dad helped me look and this is what he said.

The inputs at the vcf scale trim only has current mixed from the various vcf sources. The voltage measured at that point is millivolts.

If anyone else has any ideas of what to try or measure I’ll give it a shot.
hey, thanks for that

have attached a snippet from the schematic linked above. try measuring the outs of the keyboad ctrl switches or after r143, r124, or r154. that's where it should be at! and it should be more than a couple of milivolts. fingers crossed!
Attached Thumbnails
Behringer Model D - DIY Mods-fcvsect.jpg  
Old 4 days ago
  #19
Lives for gear
 

Quote:
Originally Posted by Maffez View Post
hey, thanks for that

have attached a snippet from the schematic linked above. try measuring the outs of the keyboad ctrl switches or after r143, r124, or r154. that's where it should be at! and it should be more than a couple of milivolts. fingers crossed!
When I measured the left of r143 I got 10v. But to the right of 143 it was millivolts. You would think the filter should have a full voltaged input somewhere.
Old 3 days ago
  #20
Gear Head
 

Thread Starter
hm... if i'll get round to it in the next few days I'll poke around as well

vertflyer, you want some total cv out, right - workaround for the time being could be cv out from pitch tp for keytracking, env out from normal socket, and, per gusto, waveform out. mix externally to taste and feed them to your modular filter cv in. not the sleekest solution but easy to accomplis
Old 3 days ago
  #21
Lives for gear
 

Quote:
Originally Posted by Maffez View Post
hm... if i'll get round to it in the next few days I'll poke around as well

vertflyer, you want some total cv out, right - workaround for the time being could be cv out from pitch tp for keytracking, env out from normal socket, and, per gusto, waveform out. mix externally to taste and feed them to your modular filter cv in. not the sleekest solution but easy to accomplis
Yeah, I have been doing something close to what you describe. One thing that I have noticed, and maybe someone else can confirm, but the filter contour out seems to have a limited range, something like 6V max if I recall. Its not quite enough to get a full range on most filters. I am curious if finding this total filter CV would give us more range.
Topic:
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Forum Jump
Forum Jump