Muff's Modules & More

frequencycentral

...teaser!

More tomorrow!
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This module is based on an LM13700 filter from an early 80’s copy of E&MM magazine’s Synbal project. I’ve adapted it for modular use: cut out non-essentials; added CV input sub-circuit (from Roland 100M VCF); changed a bunch of values; added output buffers and balanced the relative volumes of all three outputs. Actually, there is not so much left from the original design now, but even so, credit where credit’s due. Sounds great! The resonance gets squelchy but does not reach self-oscillation. However, by feeding an output back into the input you can get it to oscillate.

Yeah, I know we're gonna need soundclips. I need to do soundclips for so many projects right now (HMVCO1c, Waverider, Roland 100M VCF...) - I'll pull my finger out over the weekend - promise.

Documentation: http://www.frequencycentral.co.uk/wp-content/uploads/2012/07/FCUK-Mult imode-Build-Doc.pdf

PCB: £15 GBP
10HP panel: £15GBP

Paypal GIFT to: rickholt22 AT hotmail DOT com

mOBiTh · Posted: Wed Jul 04, 2012 7:21 pm Post subject:

lightworks · Posted: Wed Jul 04, 2012 7:49 pm Post subject:

Moog$FooL$ · Posted: Wed Jul 04, 2012 7:51 pm Post subject:

i've got some LM13600's sitting around doing nothing..... will they work?

zombie

aladan

Awesome! Just paypal'd for 2...

...

JUST KIDDING! razz

roglok · Posted: Thu Jul 05, 2012 2:28 am Post subject:

Too much noise in the MFOS MMF... eek!

Will this sound better?

nickster · Posted: Thu Jul 05, 2012 3:45 am Post subject:

Come on tomorrow already!! It's peanut butter jelly time!

So very interested in a DIY multimode filter. we're not worthy

ok I'll calm down now and drink my tea and go back to reading the paper. But come tomorrow I'll be all over the shop.

default · Posted: Thu Jul 05, 2012 4:19 am Post subject:

4hp Multimode? One can dream...

cleaninglady · Posted: Thu Jul 05, 2012 5:57 am Post subject:

ooh ! you dirty tease. booty wiggler

JJ · Posted: Thu Jul 05, 2012 6:37 am Post subject:

mikecameron · Posted: Thu Jul 05, 2012 10:18 am Post subject:

ok... it's tomorrow now...

J3RK · Posted: Thu Jul 05, 2012 10:49 am Post subject:

Wow, this exact thing was next up on my project list. An attempt at a low noise state variable using LM13700s. w00t

frequencycentral · Posted: Thu Jul 05, 2012 11:15 am Post subject:

asterisk · Posted: Thu Jul 05, 2012 12:42 pm Post subject:

looking forward to the soundclips on this one.
i have some spare LM13700s laying around too.

J3RK · Posted: Thu Jul 05, 2012 12:50 pm Post subject:

theabsent · Posted: Thu Jul 05, 2012 2:41 pm Post subject:

mOBiTh · Posted: Thu Jul 05, 2012 3:48 pm Post subject:

i know filter demos tend to verge on the pointless but can we hear it pleeeze?

nickster · Posted: Thu Jul 05, 2012 4:06 pm Post subject:

Put me down for 1 PCB & 1 panel. Please applause

Payment sent 1 PCB & 1 Panel.

Thanks

default · Posted: Fri Jul 06, 2012 2:36 am Post subject:

julien · Posted: Mon Jul 09, 2012 2:18 am Post subject:

Hello Frequency Central,
I really want to buy a kit from you but i'm waiting for some news.
Please post some soundclips for your Lm13700 filter Chugging Beers

JJ · Posted: Mon Jul 09, 2012 3:45 am Post subject:

thanatronique · Posted: Mon Jul 09, 2012 4:32 am Post subject:

Interested in this, will order one for sure. Just waiting for money. very frustrating

steffensen · Posted: Mon Jul 09, 2012 5:00 am Post subject:

Awaiting some money here too, then i will make the long awaited order! Some sound samples during this wait would be just fine by me. smile

JJ · Posted: Mon Jul 09, 2012 10:18 am Post subject:

Looks like I will have a full 84HP 3U of freqcentral modules by the end of the year! thumbs up

frequencycentral · Posted: Mon Jul 09, 2012 1:40 pm Post subject:

Time for some clips, forgive the average playing:

Lowpass:

http://www.frequencycentral.co.uk/wp-content/uploads/2012/07/Multimode -LPF.mp3

Bandpass:

http://www.frequencycentral.co.uk/wp-content/uploads/2012/07/Multimode -BPF.mp3

Highpass:

http://www.frequencycentral.co.uk/wp-content/uploads/2012/07/Multimode -HPF.mp3

Self oscillate (bandpass out fed into audio in, output from lowpass):

http://www.frequencycentral.co.uk/wp-content/uploads/2012/07/Multimode -Self-Osc.mp3

By the way, the two oscillators used were both my HMVCO1c, so it's kinda a workout for them too!

steffensen · Posted: Mon Jul 09, 2012 2:06 pm Post subject:

JJ · Posted: Mon Jul 09, 2012 4:21 pm Post subject:

I took a look into the magic chrystal ball and could see the future. My future. It is full of frequencycentral pcbs and panels and a lot of soldering to do.

julien · Posted: Tue Jul 10, 2012 4:38 pm Post subject:

Hi,
I've got a question about jack connections on the PCB:
I think tip must be soldered on the grey and blue pad, but i don't know if i have to solder the sleeve of the jack somewhere on the pcb seriously, i just don't get it

I imagine they must be connected to ground but i'm not sure. help

Thanx

frequencycentral · Posted: Tue Jul 10, 2012 4:54 pm Post subject:

frequencycentral · Posted: Wed Aug 22, 2012 7:54 am Post subject:

Photos of wiring as requested by nickster. Note that this was a prototype, PCB has changed slightly now. The new PCB has an extra pad for ground marked 'G' next to R16. You can also see how I use resistor legs to wire the CV in sockets to the pads.:

xonetacular · Posted: Wed Aug 22, 2012 1:44 pm Post subject:

Hmm this looks pretty interesting.

I've just built a couple 4MS eurorack kits and now I want to try some more DIY stuff. Do you think something like this would be a good simple enough starter project?

Also do you ship to the US and does price include international shipping?

frequencycentral · Posted: Wed Aug 22, 2012 1:50 pm Post subject:

It's a relatively simple build really, as long as you are happy to source your own parts. Tayda sell most of the components, with the exception of the LM13700 which you get get from Ebay (for example). And yes I ship to the USA and the price includes shipping.

nickster · Posted: Thu Aug 23, 2012 4:50 am Post subject:

Thanks for uploading the photos Rick. Just waiting upon some parts from Tayda and I'm good to go. If anyone is thinking about how easy this one is I can suggest that this is a pretty uncomplicated build. So if your on the fence hop off and build this. Comes with a faceplate too if you like which makes life a lot easier It's peanut butter jelly time!