[WIP] Filter, Processor, Utility (February Protos)

Category: Unknown · Tags: — · Posts: 27

#1 — Fox · 2021-02-06

I ordered more prototypes to work on!

In this order, I have been working on several new things. Here’s the short list:

State Variable Filter

HL Filter

IRIS

Attenuvert & Bias

Passive YRGB Switch (Wednesdayay suggestion)

More Quad Inverters

SHUTTER - 30 sets

Low Profile Passive Bus Boards

Long Descriptions:State Variable Filter

This module accepts one Luma signal and two voltage control inputs. The Two VC inputs control Frequency cutoff as well as Quality of the filtering. They each may be modified with the attenuverter and bias knobs. If no inputs, The pots control a reference voltage which is normalled in the jacks.

The outputs include One All Pass (thru), Low Pass, High Pass, Band Pass and Band Reject output.

Testing may prove differently, but my calculations show that the frequency cutoff may be adjustable across a range of 0Hz to around 6MHz. HL Filter

This filter outputs High Pass and Low Pass and has Voltage Control over the frequency cutoff. Just like the 8HP State Variable Filter, this one has Attenuation and Bias control of the VC input, but no Q control. I have two filter designs as to compare function versus HP width. Three of these side-by-side could be used for full RGB filtering in only 12HP.

This will have the same frequency range as the SVF. IRIS

This one is a little different. It accepts one or two luma inputs, mixes them together and offsets them by fixed DC voltages to alter thier brightness. The 6 outputs will offset the luma by +/-0.25v, +/-0.5v, and +/-0.75v Attenuvert & Bias

Pretty straightforward. One set of RGB inputs, one set of RGB outputs, 6 knobs to attenuvert and 6 knobs to bias each signal independently. 8HP Passive YRGB Switch (Wednesdayay suggestion) @wednesdayayay brought up a need for a passive 1:2 RGB switcher. It was easy enough to design so I’ll be sending them a couple for free once they arrive. This one is cool because it can be rotated or even flipped depending on the user’s need. It can be used as a 2:1 or a 1:2 switcher and is completely passive. More Quad Inverters

I’ll have some of these for sale when I make that shop page eventually. I even have a few built for sale as well. SHUTTER - 30 sets

What everyone has been waiting for. I ordered the first set of 30 SHUTTER modules and will make a for sale thread once they arrive. As before, I will put the BOM and Build guide in the thread and will offer a few built. Low Profile Passive Bus Boards

I just made these because I needed them. I am not sure if I’ll be selling them, but won’t turn people away if they ask.

#3 — reverselandfill · 2021-02-06

wow! impressive list

#4 — Robbertunist · 2021-02-07

That’s a hell of a list! I’m looking forward to the releases in the coming weeks:-)

#5 — efp3 · 2021-02-10

Looking forward to seeing them in use!

#6 — allthesixes666 · 2021-02-13

looks great, 'keeping my eye on this

#7 — Fallinggirl · 2021-02-13

I am so excited for these. I am ready to order.

#8 — Fox · 2021-02-18

New toys have arrived! As per usual, the parts to finish them are not here.

#9 — Robbertunist · 2021-02-22

This looks great Fox & really enticing

What is the smaller module in the lower row with the squares, triangles & circles on the panel?

I’ve just found the info above, cool that it was a suggestion from Paul that’s now come to fruition

Did that happen during one of the Video Group Study group video calls? :

Fox wrote:

Passive YRGB Switch

#10 — wednesdayayay · 2021-02-22

I just reached out over direct message

I can’t wait to solder up my first DIY module!

I’ll probably use one of these as a part of a larger CV bus

#11 — saiteron · 2021-02-27

great work! would love to go Pokemon-style on these and catch 'em all when they’re released into the wild

#12 — jnoble · 2021-03-18

HL filter please

#13 — jnoble · 2021-04-13

Checking in, any news on the filter?

#14 — rempesm · 2021-04-13

Still WIP but some captures from a current rev:

https://www.youtube.com/watch?v=xmafXuyAPsQ

https://www.youtube.com/watch?v=BUKuLc1YXEw

https://www.youtube.com/watch?v=uKpMLNBmlRo

https://www.youtube.com/watch?v=N5P-9VpMEA0

#15 — jnoble · 2021-04-13

Twenty characters of looking good!

#16 — phosphenes · 2022-08-17

Hey Fox, is there any news on the filters?

#17 — rempesm · 2022-08-17

The HP/LP filter is in active development.

https://www.youtube.com/watch?v=pn3TbLj-IIk

https://www.youtube.com/watch?v=V9oIsBjI9Ds

#18 — Fox · 2022-08-17

phosphenes wrote:

Hey Fox, is there any news on the filters?

Working on some final component values. The above videos are good examples of where we’re at.

You can also check out some examples (with IG compression) here: https://www.instagram.com/p/Ccqy_0UlDQN/

#19 — sean · 2023-03-30

Okay, thought I’d give this thee olde semi-annual “How’s it going with the filter?” bump.

Apologies if you’ve given updates in other locations (Discord, FB, IG, etc.), @Fox, as my usage of those platforms is somewhere between spotty and nil.

But seemed like it was maybe pretty close to completion, judging by the above demos and comments.

#20 — Fox · 2023-03-30

Thanks for asking, Sean!

What I believe to be the final revision should be going on my very next PCB order. The set I have been using in my rack have all of the corrected values bodged on and the final ones just need a fresh/updated silk screen. No one wants them to be available more than me, that’s for sure!

#21 — sean · 2023-03-30

Awesome to hear. Looking forward to it. Thanks!

#22 — Fox · 2023-05-12

One more revision. Gonna send it in.

Notable changes: I am sick and tired of populating resistors on seemingly endless revisions, so the passives are now pre-assembled. All that I need to solder are the chips, connectors, pots and trimmers. Chips can be either THT or SMD depending on what is available.

I like the board and the results a lot.

Crossing my fingers, the next print job is the last one.

#23 — Analogmonster · 2023-05-12

Looking good! That’s smart thinking for both, may be pinching these ideas for myself in the future since IC supply shortages are often still a problem. Are the ICs identical in both package options?

#24 — Fox · 2023-05-12

With these chips, all of the pins match up between SOIC and DIL and I’ve tested both options on separate builds.

LT1228, LM6172, TL072.

It works very well and will save a lot of time building them. With the smaller passive components, the board is only 35mm deep and I went ahead and made the board 4-layers as the cost difference was trivial.

I think the biggest factor for me is that this will also make putting together kits a breeze.

#25 — joem · 2023-05-13

Do I spy a footprint that can either be two SOIC TL072s or one DIP TL074?! What a nice idea! I ended up making a “SOIC8 or DIP8” footprint myself and was bummed that I couldn’t do the same for larger pin packages. But what you did is a pretty nice solution for op amps!

#26 — Fox · 2023-05-13

That’s right!

I decided fitting a SOIC-14 around the DIL-14 took up more space than two SOIC-8’s.

#27 — phosphenes · 2023-05-15

Brilliant idea on the dual footprints, will be stealing this idea for future designs!

#28 — Fox · 2023-06-15

Final boards/panels ordered, parts order being placed now.

Word on availability will be announced soon granted there are no more setbacks.