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Showing posts from May, 2011

Filters III : A-124 Wasp Filter

The A-124 is a special 12dB multimode filter using the filter circuit of the EDP Wasp, a monophonic black and yellow analog synthesizer, that was built around the end of the seventies and manufactured by the UK company Electronic Dream Plant.

I totally love the sound of the A-124 Wasp Filter module. It does have it's own special sound due to the special circuits in it which makes the module sound a little dirty and distorted. This can sound very nice with extreme filtersweeps, i often control the cut-off frequency with the pressure CV from the A-198 Ribbon Controller.

The module has 2 audio outputs; a band-pass and a combined low/notch/high pass output that can be controlled with the 'mix' knob that defines the relative amounts of low and high pass signals.
( middle position is notch )

One downside of the module is the lack of a QCV input like most A-100 filters have, so sadly the Resonance cannot be controlled via an external voltage. You can only adjust this manually.

100th PatchPierre Post

Woooooot! ...again. :-)

My 100th post already (the 50th was on December 7, 2010), and the blog is still going strong.
With fewer posts though, but the viewing rates are still slightly growing every month.
Thank you all again for regularly visiting this site and for your valuable feedback.
I hope my blog can still please the people who just got into analog (modular) synthesizers, and also provide the more advanced users with interesting links and different insights.

In this post i would like to take a quick look into the most popular of my first hundred posts.
Although i cannot exactly tell how many people read each post (many of the visitors land on the main page, where they might read multiple posts at once), i can tell by the individual clicks what the most popular posts were and tell a bit about their traffic sources.

By far the most popular post was my Busboard Access post from November 17, 2010.
I guess struggling for hours through the manuals for a complete overview of all module…

Saving Patches

One of the downsides of a modular synthesizer is the lack of memory banks.
There are times when you have finally found that perfect sound, but need some modules for other patches...
A good (photographic) memory will often do the job in the more simple cases for anyone, but for bigger patches you might need a little reminder sometimes.

To 'store' patches you have a few options;
First, always try to sample the sound you made with a (hard- or software) sampler. Although that often does not catch every aspect of your sound, it is always good to keep what you made in some audio-way. Try sampling it in all its varieties, with your favorite settings and or knob-twists.

Okay... you now have the sound , but not the list of modules that were used to make that sound.
Doepfer came up with the nice idea of patch-sheets in the last page of every module's manual.
You can print out these modules, stick them on a bigger sheet (i've even seen some on pinboards) and draw in your knob-sett…

LFO's A-145 and A-147

Low Frequency Oscillators or LFO's produce periodic control voltages that can be used as a modulation source for all kinds of other modules.

The A-145 LFO1 was the first and one the most basic single Low Frequency Oscillators that Doepfer sold.
It provides 5 different waveforms; sine,sawtooth, triangle, pulse and inverted sawtooth ,and each waveform has their individual (and simultaneous) output.
With the Frequency-knob and the 3-way switch you can select a wide range of frequencies, from on cycle every minute up to audio frequency at the highest.
A reset input allows you to synchronize the LFO signal to an external trigger signal and each trigger will re-start the waveform from its zero-point.

The most obvious use for an LFO is to do some pitch modulation on a VCO to create a vibrato and to modulate amplifiers (VCA's) for a tremolo effect, but with a creative mind you can use these two modules for all kinds of sound manipulating.

The A-147 Voltage Controlled LFO is basically …