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Blacet modifications
MUFF WIGGLER Forum Index -> Fractional Rack Modules  
Author Blacet modifications
Muff Wiggler
NOTE: I've edited this first post to provide links to the different modifications which 'have their own threads'. Be sure to check the links as more information will get posted in these threads, including photos and more detailed instructions (which I've just put up for a couple of them....more coming soon!).

----------------------------------------------

I really like doing mods to my modules. Since I don't have time to build most myself, this at least gets me tinkering. All of the mods I've done are pretty easy, definately good for someone pretty new to this stuff, and they all add cool extra functionality to the modules.

I've got the info for a bunch of mods to a bunch of different Blacet modules, however there's a few mods I haven't done, either haven't had the time or decided not to do it

but there's a few that I think are pretty cool, some even essential, for Blacet modules

1 - VCO: FM Coupling switch mod. In the factory configuration of the Blacet VCO, the FM input is AC coupled. However, the circuitry for the DC coupling already exists on the board, and is ready to go! You simply need to wire it up. There's two hookup pads on the pcb, labelled "OPT". Attach a wire to each, connect a SPST switch between the wires, and presto - Selectable AC/DC coupling for your FM input. Big difference when using CV's instead of audio into the FM in. I consider this one absolutely essential, for ease of install vs. utility gained. Check this thread out as I've just added photos and more detailed information.

2 - Mini Wave: As you probably know, the Hylander expander board, which lets you address 10 ROMs in total. Plus the addon board for it that gives it CV control over ROM selection, as well as a standalone inverter unit. Pretty major and costly upgrade, however well well worth it for those addicted to wavetable scanning mayhem or slowly clocked evolving CV or any other magic of the miniwave.... Click here for a dedicated thread about the expander including some photos.

3 - Dark Star Chaos: If you do not have a Rev. 'B' unit, (you'll know because you don't have a 'noise filter - out' jack, you can increase the output from 1v to 5v, add a output for the pure noise right after the noise filter, and add a 3-way gate switch for on/ext/momentary. All three of these upgrades have already been added by Blacet to the Rev. 'B'.

In either case however, there's another mod you can perform, that gives you CV inputs for both the attack and the decay settings. Again (thanks John!) this circuitry is all built up, one only needs to hook up each jack to the PCB using two wires, and of course drill holes in the faceplate to add the jacks.

4 - Improbability Drive - There's a mod for the ID that allows you to input any external signal into the S&H processor, and a switch to select between the external input and the default internal white noise. I believe it is fairly straightforward, the installation of a jack and a switch, and the cutting of a trace, however I don't have the full details and haven't performed it, so I cannot say for sure. I would really like to add this to my ID's. Update: Check out this thread with more detailed info and photos courtesy of BananaPlug.

There's also a DIP package on the PCB of the ID that could possibly be replaced with a panel-mounted switch, however I also haven't looked into this one yet either. I believe the DIP is to select some various quantization modes, and I think you may have to get a little fancy on switches if you wanted to panel mount the options.

5 - LFO - The LFO has a DIP switch on the PCB to select between two different cycle lengths, short mode and long mode. This one is dead simple to replace with a panel mounted SPDT switch. Check out this thread as I've just posted some photos and more detailed information.

6 - EG1 - (Detailed modding threads found here and here) As if the EG1 wasn't crazy powerful enough (seriously can you believe envelope generators are made this flexible??), it is mod central. More mods for this puppy than anything else.

There's pad on the board, again ready-to-go-thanks-john-blacet, for a second, unattenuated output.

You can add an End-Of-Cycle Pulse jack, which keeps a low voltage during the entire ADSR cycle, and then goes high when the cycle ends. This one is a bit tricky, i would say it's the next step up in complexity from the simple 'pre-wired pad' install.

Also, when using the EG1, i usually patch the inv_out jack back into the decay_cv_in jack, this gives an exponential response to the decay phase. the decay phase is the one phase in the ADSR cycle that the ear responds most strongly to, so this causes the entire envelope to 'feel' more exponential and 'snappy'. The decay knob setting itself gives you a lot of control over how much of this effect is balanced with a natural decay. Anyway I like it enough that I wired the inv-out jack directly to the decay-cv-in jack, through a panel mounted switch to turn it on and off. now I can use this without wasting a cable, and i can still use the inv out jack for something else.

There's currently two other dedicated threads with more detailed info on performing these mods, which can be found here and here.

7 - Frequency Divider - All 12 individual divisions of the second-line divider (the big rotary switch) are available on the same time, each on their own dedicated output jack, if you just wire them up. They fit perfectly on a half-panel. I made a FD Expander this way, and it turns this module into a clocking and sequencing powerhouse.

Also, there's another PCB mounted DIP switch, this one controls the state of the built-in LPF, either off, mild slope, or steep slope. This can be replaced with a panel mounted 3-way switch.

There's currently two other dedicated threads with more detailed info on performing these mods, which can be found here and here.

8 - I/O - Again a PCB mounted dip switch, which could be replaced by panel-mounted switches (plural this time). This one controls a few things, the presence of +5v aux power out the 1/4 jack, the module's input impedance, and the behaviour of the automatic AC/DC coupling detection. All these functions are obscure enough to my own uses for this module that I will most likely not ever perform this mod.

9 - Time Machine - You can add a bypass switch to your Time Machine, just drill a hole in the front panel for the switch, and hookup a couple of wires. Check out this thread for more details on this mod.

----

I know there's more Blacet modifications, so if you know of any, please post them!

Also, if you want to perform any of these mods you'll want more detailed information than this .... just let me know

have fun & don't burn your fingers
zerosum
KICK ASS!!!!
Right on man! I was hoping you would make a thread like this after hearing you explain some of these over the phone and such..
Good stuff smile
Muff Wiggler
yeah i can post pics and stuff if people are interested in doing any of these mods. none of them are very hard.
kryptic
Wow. smile I just saw this thread and I gotta agree with zerosum. This thread is ace! If you could post pics, diagrams, detailed instructions, it would be awesome and most appreciated. grin
Muff Wiggler
sure, i won't be able to take pics and write them up all at once, so let me know what modules you have that you want to mod and i'll photograph and describe them for you one at a time whever one of you guys is ready to do one

i won't be able to photography the disassembly of things, as all my mods are already done, but none are hard and I'll provide photos and good enough descriptions you'll have no problems
Muff Wiggler
just a quick reminder about these - i've created threads here in the Blacet forum for each of the mods I know how to do, describing the process in a pretty basic form that probably assumes you know a lot about what you are doing.

If any of you are jumping into performing any of these, and want more detailed instructions, or photographs, please just let me know in the appropriate thread, I'll be happy to take some shots of my work so you'll know exactly where to solder and what to do...
BananaPlug
Here's what I do to all my Frac rack and Euro rack gear. Bananafy!
Kwote
BananaPlug wrote:
Here's what I do to all my Frac rack and Euro rack gear. Bananafy!


good choice of colors.
nathankirchner
The Hex Zone can store 32 Sequences and 60 Chains (Patterns of sequences). If this is not enough for you go to

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=CAT24 C16LI-G-ND

and buy a hand full of these. ALL of the song/sequence/user data is stored on this chip. So if you have finished a song and want to keep it pull out this chip and put in a replacement. TURN THE POWER OFF FIRST obviously.

When the HZ is booted with a new chip in you will get a message saying that there is "Nothing to Load" and the HZ will format the new chip for you. If you put a chip in that has been used in the past this will not happen, rather, all of your old sequences/settings/etc will return.
Muff Wiggler
That is awesome Nathan, and very good to know 8) I think I'll have to order up of those once I get my HZ module!

More Blacet Mod news! One of our members, BananaPlug, sent me a PM detailing Improbability Drive modifications that he posted at the Electro-Music forum here.

I knew there were mods out there for the ID - just reading the manual it's apparent that it should be easy to inject an external source into the S&H engine. Anyway BananaPlug has done all the hard work and written up all the info, which I'll copy/paste into the next post.

Thanks very much BananaPlug for giving me the heads-up and the OK to repost his work here! Super cool.
Muff Wiggler
BananaPlug wrote:
Hi Folks,

The Blacet ID2510 (fancy noise source) has a lot of blocks in its block diagram. These simple mods give you a little more access. The usual disclaimers apply: don't get in over your head, forget about your warranty, etc. Also, I made mine with banana plugs so where I've added a jack and a switch you would probably use a switching mini-jack. I used very stubby switches so they don't crowd the knobs.

#1 There's a multi-mode filter with a switch that lets you select band pass or low passed noise as an input to a sample and hold. The output of the S&H feeds a quantizer and both outputs are available at the panel. Mod #1 lets you feed the S&H / quantizer with an external signal.

Add the jack & SPDT switch. Wire the jack to one side of the new switch. Take the wire off the center lug of the existing switch (Filter LP/BP) and move it to the center lug of the new switch. Run a new wire between the two remaining switch lugs.

#2 That quantizer is a nice piece of work. Good Mister Blacet even provided a choice of four scales using a little trim pot on the PCB. This mod simply remotes it to the front panel.

Remove RT2. Install a 50K linear pot on the panel. Hook up the three wires. Piece-o-cake.

#3 This one doesn't really count. A choice of internal or external S&H clock is a standard feature accomplished with a switching jack. When I bananafied this module I needed to add a switch.

That's enough for me but if you like drilling holes I suppose it wouldn't be too hard to provide patch points for the in and out of the filter.

Enjoy!


Kwote
that was awesome seeing the finished work.

if you can find the time Muff, could you post closeups of your Blacet mods too?

thanks!
Muff Wiggler
i will do so as soon as i get a chance - there's a bunch though! which ones would you like to see first?
Kwote
Muff Wiggler wrote:
i will do so as soon as i get a chance - there's a bunch though! which ones would you like to see first?


so far the VCO and the LFO are of most interest.
Muff Wiggler
Kwote wrote:
Muff Wiggler wrote:
i will do so as soon as i get a chance - there's a bunch though! which ones would you like to see first?


so far the VCO and the LFO are of most interest.


ok, done! check 'em out 8)

I also updated the first post in this thread with links to the threads detailing the info on each mod. I'll try to keep that updated with the new links as more info and more mods are added.
J.w.M.
Wow-- thanks for this wealth of modification info. I haven't modded anything yet, but when I do, this will be the first place I check for pics, etc.
haricots
how hard would it be to add CV to the Dual Filter?
BananaPlug
Binary Zone usually has two normal through jacks. To make up for that I added a switch to select the external clock and a fairly large pullup resistor (220K) on the line from the Gate jack.
Reese P. Dubin
OOOoooOO was gonna finish my Binary tonite.

Whats the theory on the added resistor on the gate jack if ya dont mind me asking?

Thanks for all the hints Banana, great help on this evil new path of mine.
BananaPlug
Quote:
Whats the theory on the added resistor on the gate jack if ya dont mind me asking?

The standard BZ has a switching jack that makes a connection when nothing is patched in. I found that a high value pull up resistor worked fine with a banana jack. Any signal I plug into the jack is much lower impedance and effectively takes over.
Reese P. Dubin
Brilliant!

Saves me drilling a second hole. Many thanks.

Oops, so wait the extra 200k is in line after the jack on the way back to the PCB? Sorry, just did some reading about pull ups and couldnt exactly make it gel with this situation...plus Im pretty much a dumbass!
BananaPlug
You know, I'll have to look at it and get back to you tomorrow. It's similar to something I did on another module and I don't want to get my stories mixed up.

EDIT: Sorry for the delay. Here's a picture of what I did. Very simple.
D/A A/D
Anyone know how to mod the DSC to hold open?
Reese P. Dubin
Oh just upload the schematic for us, we'll figure it out for you!!!!!

I KEED

Yeh, I foolishy did not buy any of the 3 dark stars that popped up on ebay in one week like a fool sucker. Man that was dumb, i love this bacet stuff. I want to build ones that i dont even need cuz it is such a fucking pleasure.

Thanks for updating with the pic BP, thats how i did it and it worked a charm. I really need to get some serious time to spend with my Hex now...
D/A A/D
Reese P. Dubin wrote:
Oh just upload the schematic for us, we'll figure it out for you!!!!!

I KEED

Yeh, I foolishy did not buy any of the 3 dark stars that popped up on ebay in one week like a fool sucker. Man that was dumb, i love this bacet stuff. I want to build ones that i dont even need cuz it is such a fucking pleasure.

Thanks for updating with the pic BP, thats how i did it and it worked a charm. I really need to get some serious time to spend with my Hex now...


Ta Da:
http://www.hotrodmotm.com/ds_mods.htm
panda30y
Is it easy to modify the blacet modules for banana jacks?
sandyb
panda30y wrote:
Is it easy to modify the blacet modules for banana jacks?


afaik it's not too bad. get hold of bananaplug - pretty sure he's done a few
panda30y
Yeah, I had the same thought too... I should just PM him I suppose.
fluxmonkey
D/A A/D wrote:
Anyone know how to mod the DSC to hold open?


i just replaced the pushbutton on mine with a toggle switch: spdt, center off, one side momentary.

bbob
Randaleem
fluxmonkey wrote:
i just replaced the pushbutton on mine with a toggle switch: spdt, center off, one side momentary. bbob

My favorite Switch! IMO Many locations benefit having momentary downwards, locking upward. All EG's for example. I much prefer it to a red PB.

Kind regards, Randal
Reese P. Dubin
SUPER EASY to mod to bananas. I even did the Hex Zone which mounts the jacks on individul boards...again really easy.

BananaPlug charted the path for all of us, he made it simple for the followers.
Gloworm
edit
antennafarm
i have a rev 0 dark star chaos... where's the output mod? the page on hotrodmotm mentions it with a link to blacet's site buuuuuut that info is no longer on the tech page!

[edit!]

i contacted john blacet and he says:

Quote:
The rev B board has an amplifier to boost the output level. This is just a
basic op amp circuit.
stevenclements
I just bought a Blacet DF2420 Dual Manual Filter Bare PCB and pot kit...

will be interested to hear this in action nanners

Steve
BananaPlug
Here's my bananaified DF2420. You can see the two toggles I've added to replace the normals.
It's peanut butter jelly time!
stevenclements
Very nice bananaified DF2420! applause

I was thinking of a synth.com or a motm panel as the whole kit is no longer available for this puppy, and I've got nothing but room in those racks.
sdc
parasitk
BananaPlug wrote:
You know, I'll have to look at it and get back to you tomorrow. It's similar to something I did on another module and I don't want to get my stories mixed up.

EDIT: Sorry for the delay. Here's a picture of what I did. Very simple.


Thread necromancy!

Noob question: Will this pullup resistor concept work for most switching jack situations, or is the Gate(RST) jack unique?

I think I'm going to start converting my Frac to banana, but honestly I'm a tad overwhelmed at what to do w/o fucking things up.
Cat-A-Tonic
Here is a link to DGTom's Klangwerk modification thread.
https://www.muffwiggler.com/forum/viewtopic.php?t=12427&highlight=klan gwerk+mod
It really belongs with these other links in this thread so that others may find it more easily.

In other news,
I've repanelled a few Blacet modules to make space in the rig and increase density.
The Mixer Processor, Mini-Wave, and I/O are now in home-made 1FU panels.
The I/O has the 1/4" jack and breakout switches for impedance and +5v options (replacing the DIP switches on the board) mounted in a Frac ear.

Here is a pic of the Mix/Proc:

I am still undecided as to whether I should paint it,
stamp it with letter punches, and infill with lacquer sticks,
or just leave it as is with the dymo labels...
werock
I was thinking of modifying my seq switch to have an external reset - it would seem a useful thing to have.

My seq switch has already been modified so the dip switch that selects between 3/4 steps has been brought out to the front panel with LEDS for each step, plus an unused extra socket on the front panel. I could just wire up the extra socket as a clock thru, but I like the idea of an external reset.

Has anyone done something like this? I guess it just needs a couple of transistors & resistors to buffer the input.
Mark Space-Ratio
I want to raise the o/p level of my early DSC but there are no references as to how to do this anymore.
Any pointers?
cheers
¬¬¬
DGTom
super-simple "mod" for the OG Frequency Divider;

All the divided outs are buffered by a 4050 Hex Buffer, swap it for a 4049, the inverting version & you get divisions you can build drum parts with thumbs up

I also modded mine to have 4 fixed outs & 1 selected by the rotary switch, it required cutting a trace to get an extra buffer - or free the one from the multed one on the panel - but its a pretty cool beat-box now grin

My next experiment will be with the Reset In, at the moment it 'holds' the counter with for as long as the gate lasts... trying to sync multiple dividers this can be a pain.
Adam-V
Great info!

Try ken's gate to trigger trick. A cap, diode and resistor might just sort your reset issue out.

Cheers,
Adam-V
BananaPlug
The Time Machine has clever filtering to reduce the BBD clock noise and deal with increasing aliasing from lower sample rates as delays get longer. The clever part is using switched capacitor filter chips. One on each end of the BBD. These filters take a clock input which determines the cutoff frequency. The BBD clock is a lot faster than what the filters use so there's a chip dividing it by 20. It's a slick way to get everything to track as delay time is adjusted.

after playing with the TM for a while I could see the appeal of having it go all dark and murky as you stretch out the delay. On the other hand I wouldn't mind hearing more BBD artifacts in return for not having so much of the signal rolled off.

So, here's the mod: Change the clock divider from /20 to /16. The dual decade counter U9 is setup as a divide by 10 feeding a divide by 2. I put in a binary counter setup as a divide by 4 feeding a divide by 4.

1. Remove U9 (CD4518)
2. Obtain a CD4520 and do a little jewelry work:

4. Stick a cutoff resistor lead in pin 11 of the socket
5. Plug in your creation and attach that lead to pin 12

6. Check your work.

The result is more subtle than I expected but sounds pretty good. Here's a few minutes of noodling around. Blacet VCO to VCA to Time Machine. It starts out dry. The wilder stuff is in the second half.

Have fun! nanners

edit: Hmm, I thought I'd annotated this already but...
The fact is, this divider is part of a PLL so the effect on the filter clock is reversed. You can try dividing by 24 or 21 but you'll probably start hearing the whine of the clock along with any extra signal you get.
PrimateSynthesis
BananaPlug asked me to post here from my Time Machine thread
https://www.muffwiggler.com/forum/viewtopic.php?t=34693
in For Sale/Trade.

While I would prefer not to post schematics that would include part of John Blacet's design, I am willing to answer any questions.

In order to have continuously variable input aliasing, a panpot circuit -- built on a little daughter board -- goes from the input (R27) to the amp before the filter (R27) and the amp after the filter (R23). It uses the same resistor values. Since it is looking into the exact same impedances, the mod is invisible to the rest of the circuit. It does not require cutting traces or replacing any components, so the mod is completely non-invasive, and can be easily removed.

Since the Time Machines uses TL074's, I used a TL072, the dual version of the same amp.
Cat-A-Tonic
Blacet Sequential Switch modification.

Quoted from WeRock:
Quote:
Ok, here's a couple of photos and brief explanation (bearing in mind I didn't do the mods)

Underside of PCB:



4 tiny holes have been drilled in the PCB - 3 are for the stage out LEDS, which connect via a resistor to the IC pins and 1 for a common ground connection. The white wire from pin 8 is the ground connection.

Top Side:



Ignore the gray, pink & orange wires, they are for the 3/4 stage select switch which has been brought out to the front panel.

The white ground wire from the first pic doesn't have any insulation on this side, so you can just see the bare wire marked 'GND' next to the 3rd jack down. This connects one leg of all the LEDs to ground.

The 3 stage out wires that we saw on the underside connecting to the IC pins are the legs of the 3 vertically mounted resistors, with wires going from the other eend of the resistors to the LEDS.

Electrically it is all quite simple, just connect the resistors directly to pins 3, 2 & 4 of the 4017 chip and the other end to the LEDs. It just involves drilling through the PCB, which could of course end in

And you have to drill holes in the panel for the LEDs.

I'll do my best to answer any more questions...


Please put the pics here when you get a chance WeRock.
werock
Here you go...

Underside of PCB:



4 tiny holes have been drilled in the PCB - 3 are for the stage out LEDS, which connect via a resistor to the IC pins and 1 for a common ground connection. The white wire from pin 8 is the ground connection.

Top Side:



Ignore the gray, pink & orange wires, they are for the 3/4 stage select switch which has been brought out to the front panel.

The white ground wire from the first pic doesn't have any insulation on this side, so you can just see the bare wire marked 'GND' next to the 3rd jack down. This connects one leg of all the LEDs to ground.

The 3 stage out wires that we saw on the underside connecting to the IC pins are the legs of the 3 vertically mounted resistors, with wires going from the other eend of the resistors to the LEDS.

Electrically it is all quite simple, just connect the resistors directly to pins 3, 2 & 4 of the 4017 chip and the other end to the LEDs. It just involves drilling through the PCB, which could of course end in sad banana sad banana sad banana

And you have to drill holes in the panel for the LEDs.

I'll do my best to answer any more questions...
idiotunderground
anyone else attempted seq switch mods?
e-grad
werock wrote:
Electrically it is all quite simple, just connect the resistors directly to pins 3, 2 & 4 of the 4017 chip and the other end to the LEDs. It just involves drilling through the PCB, which could of course end in sad banana sad banana sad banana


One could always use longer wires to avoid any drilling through the pcb.
Cat-A-Tonic
Drilling through PCBs is not difficult.
I have done it on several occasions when no provision for standoff mounting holes was provided.

If you have to drill holes in a PCB, be sure to:
- avoid circuit traces,
- put some scrap wood under the PCB,
- start with a very small diameter drill-bit to make a pilot hole,
- where a mask to avoid breathing in nasty fiberglass dust.

Sorry if all that was painfully obvious.
e-grad
Babaluma wrote:
1 x Blacet EG1 with the following mods:
A) Separate three position switches on the Attack and Decay parameters, to give you Log., Lin., or Exp. curve responses


I just want to make sure that I've understand how the mod above is done:

Inverted out to the switch contact of the CV In jack = expotential; the normal out to the switch contact = log. An on/off/on switch inbetween the outs and the jacks allows to choose btn log, exp and lin?
Babaluma
Cat-A-Tonic did the mod, I just helped, so hopefully he'll respond soon!

It REALLY opened up the versatility of the EG1, especially for slow/LFO type stuff, and I guess for rhythmic stuff too.
e-grad
Babaluma wrote:
Cat-A-Tonic did the mod, I just helped, so hopefully he'll respond soon!


I hope he'll chime in!
Cat-A-Tonic
e-grad wrote:
Babaluma wrote:
1 x Blacet EG1 with the following mods:
A) Separate three position switches on the Attack and Decay parameters, to give you Log., Lin., or Exp. curve responses


I just want to make sure that I've understand how the mod above is done:

Inverted out to the switch contact of the CV In jack = expotential; the normal out to the switch contact = log. An on/off/on switch inbetween the outs and the jacks allows to choose btn log, exp and lin?

Yes, exactly.

What would be even better in practice
is having a bipolar attenuator instead of a switch on the CV inputs of Attack and Decay.
(like Envelator, VCS) or this:
http://www.steamsynth.com/m_VCADSR.aspx

I chose on-off-on switches with consideration to available panel space.
This allows for quick selection of the extremes, but nothing in between.

Try patching the feedback through a Mixer/Processor or other polarizer/inverter to get a feel for it before doing the mod.

Patch the feedback through a VCA if you want voltage control of slope shape per segment.
e-grad
Cat-A-Tonic wrote:
Yes, exactly.

What would be even better in practice
is having a bipolar attenuator instead of a switch on the CV inputs of Attack and Decay.


Thanks! I think I'll go for the switch and patch a bipolar attentuator when needed. However, I'll give it a try before the mod as suggested by you.
e-grad
Sorry, if I'm asking the obvious.

Given I want a bipolar attentuator could this be achieved without any active parts just by adding one pot?

Assuming I wire the pot as follows: pin 1 to EG out; pin 3 to EG inv. out and the the wiper (pin 2) to the switch contact of the CV in jack. Would that work?
Cat-A-Tonic
One new idea to add about this...

If you play with the polarizer to find sweet spots in the slope shapes
you can make presets with the switches
by wiring resistors of the chosen value in the feedback path.
8_) Blacet
or you could use trimpots.


EG1 rules.
There is only one here, but it's here to stay.
It's brother was passed on to Mr. Nikmis.


Try playing the CVs on it (especially sustain)
with the a pressure controlled CV source of some sort.
Sequencing Envelope CVs is fun too.
e-grad
Cat-A-Tonic wrote:
If you play with the polarizer to find sweet spots in the slope shapes you can make presets with the switches by wiring resistors of the chosen value in the feedback path.


woah

Great idea. However, I'm going to insert a pot a written above that should cover my needs.
Cat-A-Tonic
e-grad wrote:
Sorry, if I'm asking the obvious.

Given I want a bipolar attentuator could this be achieved without any active parts just by adding one pot?

Assuming I wire the pot as follows: pin 1 to EG out; pin 3 to EG inv. out and the the wiper (pin 2) to the switch contact of the CV in jack. Would that work?

I don't know if your knob wiring is correct or not,
but I think adding bipolar attenuators required a bit of extra circuitry.

However,
if you put the on-off-on switch to one side of a passive attenuator pot
you can have a full knob turn of control over the slope in one direction and still flip to an inversion on the fly.

This sort of interface does start to take up a bit of space,
but it's nice to have immediate interfaces especially for performance
and reduction of unnecessary patch cable clutter.
e-grad
Cat-A-Tonic wrote:
I don't know if your knob wiring is correct or not,
but I think adding bipolar attenuators required a bit of extra circuitry.


Just have made a quick test using alligator clips: Yes, it works. I guess, there's no extra circuitry needed since both outs and ins are already buffered.
Cat-A-Tonic
e-grad wrote:
Cat-A-Tonic wrote:
I don't know if your knob wiring is correct or not,
but I think adding bipolar attenuators required a bit of extra circuitry.


Just have made a quick test using alligator clips: Yes, it works. I guess, there's no extra circuitry needed since both outs and ins are already buffered.

Awesome.

I'm eager to see what you come up with for a panel solution.
e-grad
The orignal idea was one space Frac for 2 EG1s plus some extra outs for my Freq Div/FD2020. However, this might not work any longer due to the limited space.
vmgas
i want to add a switch to my blacet psu
i really hate having to reach down and flip a power strip
what switch do i need and where do i clip?
guhh h h thanx kids
fracmonkey
Modifying an AC power supply can be hazardous to your health.

I've actually attached a power strip to the side of the rack box so I don't have to bend over! Bending over is not the hard part; getting back up is... hihi
noisefor
vmgas wrote:
i want to add a switch to my blacet psu
i really hate having to reach down and flip a power strip
what switch do i need and where do i clip?
guhh h h thanx kids


unless you know what your doing with power i wouldn't mess... i use these (attached to my case):

http://www.amazon.com/Belkin-Conserve-Power-Switch-F7C016q/dp/B007PVC1 2W/ref=sr_1_3?s=electronics&ie=UTF8&qid=1337699608&sr=1-3
vmgas
im ok with messing
i used to work as an electrician so i i know how not to die
anyway im asking here because my friend who did so doesnt remember what he did when he made a switch for his
D/A A/D
The only "safe" way is to cut ground...
Cat-A-Tonic
Muff Wiggler wrote:

8 - I/O -
Again a PCB mounted dip switch, which could be replaced by panel-mounted switches (plural this time).
This one controls a few things, the presence of +5v aux power out the 1/4 jack,
the module's input impedance,
and the behaviour of the automatic AC/DC coupling detection.

All these functions are obscure enough to my own uses for this module that I will most likely not ever perform this mod.

I'm a madman.
Now my Blacet I/O has short bat switches wired up in a Frac ear to select its usage for driving foot pedals and FSRs.





Guinness ftw!
scozbor
that's awesome
SlayerBadger!
Norman_Phay
I've been thinking a bit recently about the octave socket on the VCO. I only ever use this by plugging the out from the mix/proc into it and using the bias knob as, in effect, an oct up/down switch. I do this quite often and have never used it in any other way that I can think of. I'm wondering wether to replace it with a switch or not, which would save patching for such a simple, yet often used function. Has anyone done this to theirs?
Babaluma
i only ever used to used mine in that exact same way too norman. a switch would be great for this, if you could tap a variable +/- voltage source from somewhere.

remember once trying to feed audio into it, but the results were not great sounding. might be good for "noise" though.
fracmonkey
I usually have it connected to the clock out of the Hex Zone. Since the clock out can be divided by 2, 4, 8 etc, this adds some interesting variety. If the sequence is an odd length then you get a more variable pattern.
Cat-A-Tonic
Thanks for the I/O props Scozbor.

fracmonkey wrote:
I usually have it connected to the clock out of the Hex Zone. Since the clock out can be divided by 2, 4, 8 etc, this adds some interesting variety. If the sequence is an odd length then you get a more variable pattern.

Same here with dividers/logic.
The octave jack is awesome for sequencing.
slow_riot
yeah octave VC is much more valuable to me than hand switching.

also great for LFO usage!
BananaPlug
Finally got around to this
1. Bananafication
2. Center column jacks top to bottom are /4, /8, /16
3. Switch duplicates the S1 and S2 of the internal LPF switch

In case you don't know this one, there's two things going on here. A big binary divider chain feeds to rotary switch. Switched output is available at the red Out jack in the left column and lights the LED. Then on the right you have different divisions and a mixer followed by a little LP filtering and output from the AC coupled black jack at the bottom left.





The filter switch effects are subtle. With an SPDT I can only get the first three out of four settings.

The divisions are tapped right off the big rotary switch. Those divisions seemed the most useful. I usually have a flip flop around for dividing by 2.

Long live Blacet modules! nanners
dJ dAb
Finally got around to building an expander (LEDs temporarily placed behind jacks for testing. Soon to be panel mounted)

J3RK
dJ dAb wrote:
Finally got around to building an expander (LEDs temporarily placed behind jacks for testing. Soon to be panel mounted)

[/img]


Nice!

I'm actually thinking about back-lighting the jacks in my 5U system. I set it up in front of a monitor the other day, and the light coming through the jacks was pretty cool.
dJ dAb
J3RK wrote:
Nice!

I'm actually thinking about back-lighting the jacks in my 5U system. I set it up in front of a monitor the other day, and the light coming through the jacks was pretty cool.


Does look really cool but such a bummer once patched up though... no more light. Need illuminated jacks ;o)
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