# Pro-Filter



## SYLV9ST9R (Aug 20, 2020)

This was one of the first board I purchased, as I play with synths and a drum machine, and filters are always fun to incorporate in these kind of setups
Easy build, but pretty tight fit at the top, I had to cut off the « switching pin » in order for the DC jack to fit (because I NEEDED to have a red DC jack to go with the color way… )
I tried to have fun with the design using pictograms, and even if the clear coat isn’t perfect (there is some speckles of dirt enclosed, as I do my spraying outside near my shed), I like the result.
I think I’m going to have fun with this one, the range seems nice, and the -/+ switch seems useful, both for sounds and rapid cutting between mild/harsh setting.


----------



## Danbieranowski (Aug 21, 2020)

SYLV9ST9R said:


> This was one of the first board I purchased, as I play with synths and a drum machine, and filters are always fun to incorporate in these kind of setups
> Easy build, but pretty tight fit at the top, I had to cut off the « switching pin » in order for the DC jack to fit (because I NEEDED to have a red DC jack to go with the color way… )
> I tried to have fun with the design using pictograms, and even if the clear coat isn’t perfect (there is some speckles of dirt enclosed, as I do my spraying outside near my shed), I like the result.
> I think I’m going to have fun with this one, the range seems nice, and the -/+ switch seems useful, both for sounds and rapid cutting between mild/harsh setting.
> ...


You know what I’m gonna say... let’s hear it! . Looks great!


----------



## SYLV9ST9R (Aug 21, 2020)

Danbieranowski said:


> You know what I’m gonna say... let’s hear it! . Looks great!


Thanks! ?
The colorway for the knobs was inspired by this post.


----------



## HamishR (Aug 22, 2020)

Choice of jacks is key to getting everything into the box!  I have been using the black plastic box-type Switchcraft jacks which fit more easily than the open ones. Recently I bought some Lumberg jacks to try because they seem even smaller. I primarily use 1590B size boxes but still like having the sockets all on top.


----------



## SYLV9ST9R (Aug 24, 2020)

HamishR said:


> Choice of jacks is key to getting everything into the box!  I have been using the black plastic box-type Switchcraft jacks which fit more easily than the open ones. Recently I bought some Lumberg jacks to try because they seem even smaller. I primarily use 1590B size boxes but still like having the sockets all on top.


The issue here was the DC jack against the pot cover. I just snipped the extra (switching) pin and it fitted. But yes, those Lumber jacks are nice, I mostly used them on my builds, and I'm also looking at doing some in 1590B.


----------



## daeg (Aug 24, 2020)

I'm torn between this and the Unicabsim at the end of my chain. Anyone used both?


----------



## SYLV9ST9R (Aug 24, 2020)

daeg said:


> I'm torn between this and the Unicabsim at the end of my chain. Anyone used both?


Just built both. I would definitely recommend the Unicab for the end of chain.
It’s much easier to dial in and really beef up your tone if you’re going direct.
It does makes playing direct more akin to playing through an amp.

The Pro-Filter takes more time to get used to the control. You can do more drastic cuts and filtering, which is great for some application (I tried it today on a synth and a drum machine, and it was pretty nice), but, with my limited time with them, I find the Unicab more geared towards guitar, and it enables you to tweak more frequencies at the same time.

Hope that this makes sense, and another option is build both, like me! I actually have the Pro-Filter, and the the Unicab at the end of my chain.


----------



## daeg (Aug 24, 2020)

SYLV9ST9R said:


> Hope that this makes sense, and another option is build both, like me! I actually have the Pro-Filter, and the the Unicab at the end of my chain.



Funny you should say that. I actually built 4 unicabs (gifts for friends). I go back and forth between loving it and not finding it useful as a standalone EQ. There are most definitely amp eq settings that can only sound worse when the unicab is kicked on. But then there are also more neutral amp settings where you can get very rich, nuanced tones when you engage the unicab. I think the challenge is, unlike an EQ pedal, you can't dial in a flat / neutral / transparent tone with it to use as a baseline.


----------



## Barry (Aug 24, 2020)

Dig the graphics


----------



## SYLV9ST9R (Aug 24, 2020)

Barry said:


> Dig the graphics


Thanks!



daeg said:


> Funny you should say that. I actually built 4 unicabs (gifts for friends). I go back and forth between loving it and not finding it useful as a standalone EQ. There are most definitely amp eq settings that can only sound worse when the unicab is kicked on. But then there are also more neutral amp settings where you can get very rich, nuanced tones when you engage the unicab. I think the challenge is, unlike an EQ pedal, you can't dial in a flat / neutral / transparent tone with it to use as a baseline.


I will be mainly using it playing amp-less, so my answer was thinking along those lines. And I only had limited time with it as I boxed it last Friday. But for that application, I found it a notable improvement.


----------



## H3R3T1K (Nov 19, 2021)

Hi everyone. I registered to ask about this pedal. I was in the market for a high pass filter for bass guitar specifically a pedal that can be used to have a roll off between 20 and 100Hz so as to not overload my drive pedal with useless sub lows. Can this build do this and if so how would I set it? Also do you recommend putting this before or after compression? I’m not sure if I actually need a comp anymore when I have this, distortion and tube sim from the Sansamp.


----------



## SYLV9ST9R (Nov 19, 2021)

H3R3T1K said:


> Hi everyone. I registered to ask about this pedal. I was in the market for a high pass filter for bass guitar specifically a pedal that can be used to have a roll off between 20 and 100Hz so as to not overload my drive pedal with useless sub lows. Can this build do this and if so how would I set it? Also do you recommend putting this before or after compression? I’m not sure if I actually need a comp anymore when I have this, distortion and tube sim from the Sansamp.


I would think so, but not sure what the sweep-able frequency range is on it.
It's a state variable filter with mixer controls for LP, BP and HP that go to a summing mixer.
Then you have a frequency control and a "resonance"(that acts a bit like a Q and dampens some feedback freq)

To set it, you would set the high pass with the frequency and resonance accordingly, the control are quite interactive.
I would tend to say after comp, but then it's because I put my comp pretty early in my chain.
Sorry not to be of much more help, but the only one I have on hand right now is unbuilt...


----------



## H3R3T1K (Nov 19, 2021)

It’s still hard for me to grasp how it works. I can tell there’s 3 filters but I don’t understand how you can set 3 of them with only one frequency setting unless only one can filter can be active at a time. The Q is the slope of the roll off as I understand it as in how steep it is from hard cut to soft cut and vice versa.

I’m new to the concept of HPF and LPF for bass guitar but once I understood it it made a lot of sense to me especially with regards to HPF since I play with lots of distortion which muddies up so easily on bass. Now I’m eager to try it because for quite a lot of people a HPF is integral to their setup as in a pedal they can’t live without.


----------



## SYLV9ST9R (Nov 19, 2021)

The three filters work in parallel and then go to a summing mixer how I understand it. So there’s crossover in the frequencies but it’s a really helpful tool to sculpt your tone. I built on in a box paired with a RAT and it sounded great with distortion. Go for it!


----------



## H3R3T1K (Nov 19, 2021)

I’m in Germany and I buy from Musikding (English language available). I’m trying to have a builder put the Pro Filter in a small enclosure together with their Squeezer which is an Orange Squeezer clone that the owner said is bass ready. No foot switch. Both meant to be on all the time. I was looking for a minimalistic comp that doesn’t remove all dynamics before the drive. This might be it.


----------



## H3R3T1K (Nov 21, 2021)

SYLV9ST9R said:


> The three filters work in parallel and then go to a summing mixer how I understand it. So there’s crossover in the frequencies but it’s a really helpful tool to sculpt your tone. I built on in a box paired with a RAT and it sounded great with distortion. Go for it!


I'm just worried that I can't dial in something I would do with the Broughton Always On HPF as in select a roll off frequency and go. With the Pro Filter I would never be able to tell the actual roll of frequency, especially not knowing the sweep. There's no info on this. Also how would I set the other controls if I want the HPF only?

The description on the MD website seems off:



> The Pro-Filter offers flexible control over tone by creating several different response options. Low pass response boosts low frequencies and attenuates high frequencies; high pass response boosts high frequencies, and attenuates low frequencies; bandpass response boosts a specific frequency range; and notch response attenuates a specific frequency.



There's no boosting of frequencies with HPF and LPF right?


----------



## SYLV9ST9R (Nov 24, 2021)

H3R3T1K said:


> I'm just worried that I can't dial in something I would do with the Broughton Always On HPF as in select a roll off frequency and go. With the Pro Filter I would never be able to tell the actual roll of frequency, especially not knowing the sweep. There's no info on this. Also how would I set the other controls if I want the HPF only?


Been also looking, but couldn't find info on the sweep/frequency


H3R3T1K said:


> There's no boosting of frequencies with HPF and LPF right?


Not to my (limited) knowledge, it's more about attenuating. If you start with the 3 filters maxed, you get a flat response and then you can use the filters - set at the same freq -  turning CCW.


----------



## giovanni (Nov 27, 2021)

The signal is split to each of the three different filters and the output is then mixed back together. The filters’ frequency is coupled so the one frequency knob controls the low and high pass cutoff and the center frequency of the notch filter. The Qs are also all coupled together in a similar way. The filters are all active so I wouldn’t be surprised if there was a frequency boosting effect but I can’t tell exactly how much from the schematic.

Edit: by that I mean I didn’t look at the schematic enough or did any math


----------

