Farfisa Mini Deluxe Compact - Sand, software and sound

Combo organs got me into this mess. 🙂

Back in the day, I played a Farfisa Mini Compact Deluxe. Even though it didn’t have many tabs or reverb, it was enough to cover Wooly Bully and the rest of the Top 40 hits. I always wanted a Vox, but the Jaguar and Continental were always out of my financial reach.

Farfisa and Vox each had their own distinctive tone. The Farfisa is raspy and nasal. The Vox is brighter and more cutting. Farfisa offered more vibrato options while Vox is just ON/OFF. Either one could quease (or cheese) your stomach when overdone. 🙂

There are several great on-line resources if you would like to know more about Farfisa, Vox and some of the lesser competitors (e.g., Gibson, Fender, Acetone). My two favorite sites are Combo Organ Heaven and The Vox Showroom. It’s also fun to browse E-bay and Reverb.com for vintage organ gear and spare parts. I also recommend the book “Classic Keys” by Alan S. Lenhoff and David E. Robertson.

Internally, the 1960’s Vox and Farfisa models employed tone generation boards — one board for each of the twelve semi-tones in an octave. Each board consisted of an oscillator for the highest pitch (e.g., C6) and dividers for the corresponding pitches one or more octaves down (e.g., C5, C4, C3). A schematic for the Farfisa Mini Compact Deluxe tone generator board is shown in the picture below.

The oscillator is, essentially, a square wave generator and the divider stages are a ripple carry counter. The square wave generator feeds the counter and each stage of the counter divides down by a power of 2, thereby producing the lower octaves. The square wave generator is on the left with five divider stages arrayed to the right.

Each board has different capacitor values (C1A to C5A) depending upon base pitch (C to B). The generator is tuned by a variable inductor coil. This darned coil was delicate back in the 1960’s and cost me an expensive repair when I tried to tweak the F# tuning. If you’re contemplating ownership of such a vintage instrument, don’t suffer delusions about the fixing and maintaining a vintage beast. Sixty or seventy years on, these critters are difficult to maintain.

Once the basic tones are generated, they are sent through a rat’s nest of wires comprising the key and bus bar switching network. Then, the individual (bus bar) signals are mixed and go to filters. Farfisa and Vox have different filters, giving each brand a distinctive voicing flavor. Farfisa routed its signals into a switched passive filter network while Vox sent its signals into drawbars. The Farfisa filters are switched in and out by the front-panel voice tabs while the Vox allows a mix of flute and reed tones. The Vox Jaguar employed an approach similar to Farfisa (tabs), letting Vox offer a cheaper alternative to the Continental.

The picture above shows the Vox Continental drawbar schematic. Key contacts switch signals onto four bus bars: 16′, 8′, 4′ and Mixture. The four main drawbars (1, 2, 3, and 4) mix the incoming ranks into a single signal which goes to the so-called sine and reed drawbars (5 and 6). Drawbar 5 filters the incoming square waves producing a sine-like, flute tone. Drawbar 6 doesn’t filter the incoming square waves and produces a brighter, reed tone.

If you would like to know more about Farfisa and Vox internals, I recommend getting acquainted with ElectroTanya. ElectroTanya is an on-line server providing service manuals for current and old gear. You can download up to five service manuals for free each day. The user interface is a little funky, but ElectroTanya is a terrific resource for out-of-print manuals. Here are links to the keyboards mentioned in this blog post:

Please keep these designs in mind. The oscillator/divider approach gave birth to the top-octave tone generator design that reduced the cost and complexity of organ tone generator boards. Thank you large scale integration (LSI).

Martinec wrote two of the best free combo organ VST emulations ever: Combo Model F and Combo Model V. You can still find copies of the Martinec VSTs on the Web. Get your combo groove on!

Arduino people should check out my sampled 60s Combo Organ (MidiVOX). I managed to get four voice polyphony out of an Arduino! Lo-fi heaven.

A Keyboard Corner member asked what people did for keyboard amplification before PA. Man, that question really kicked off some memories.

Back in the day (1966), I played a Farfisa Mini Compact Deluxe through an Ampeg SB-12 bass amp. It was all I could afford. Mom and Dad lent me the money and I mopped floors at the local donut shop to pay them back. The shop had a wooden floor that was impregnated with grease. I still can’t face donuts to this day. 🙂

While packing for the house move, I found an original Farfisa brochure from the 60s era.

The Portaflex was pretty cool with its flip top. The amp was mounted to a covered board which acted as a base for the head and, when flipped over, it became the cabinet cover. The clamps held the base/cover board in place and did double-duty as the speaker connections to the cabinet.

The SB-12 had a 12″ Jensen speaker powered by a 25 Watt tube amp. It weighed 47 pounds — the first of a long line of heavy schleps.

Being the 1960s, of course, that wasn’t enough. Since I started playing with electronics and DIY at an early age, I tried my hand at an extension cabinet. I somehow came into a 15″ JBL speaker with a small tear in the cone. Impedance be damned, I just hooked it up in parallel with the Jensen via the clamps. Before building a cabinet, I would carry the JBL around in a suitcase which doubled as a “cabinet.” (!) The tear in the cone lent more bad-itude. [Why fizzy digital distortion doesn’t cut the mustard.]

In the R&B band, the guitars and vocals went through matching Ampeg guitar amps (probably Gemini’s). Only the top local bands could really afford PA for vocals (typically Fenders). Nobody put instruments through PA. The bass player had a Guild ThunderBass amp with that funky head. The bass player was quite good and laid down decent grooves. Can’t remember too much about the psychedelic band…

My failed experiments at extension and PA speaker cabs wound up as end-of-gig props. When we saw The Who trash their gear, we thought “What the heck!” I’d pull one of the legs off of the Farf and ram it through one of the prop cabinets.

My dream rig would have been a Vox Continental through a Fender Twin Reverb or Fender Super Reverb. I copped the Fender tilt-back idea and built a tilt-back stand for the SB-12. That got the speaker pointing up toward my ears.

Both the Connie and the Fenders were out of my financial reach. It took me three years to pay back my folks. By then, I had to sell the whole rig in order to make the college tuition nut. Given the rigors of college math, physics and computer science, it was the end of playing for quite a while. I can’t believe how much a vintage SB-12 fetches on the market these days!

The Farfisa Mini Compact Deluxe left me with no delusions about 1960s electronics. I tried tuning the F# oscillator and bunged the tuning coil. That was an unnecessary repair expense. That’s why I’m happy as a clam to play the Yamaha Reface YC today. The YC does a good job nailing the Farfisa and Vox.

A few other memories stick out like playing music fairs on stage/demo gear with the psychedelic band. One stage was incredibly small and I had a horn driver literally right in my ear. We played Doors, Steppenwolf, Vanilla Fudge, etc. at phenomenally loud volume, attracting every biker within earshot. They loved us. I think I still suffer hearing loss from those jobs.

Before signing off, I want to plug “Classic Keys: Keyboard Sounds That Launched Rock Music” by Alan Lenhoff and David Robertson. I received a copy yesterday and gave it a quick browse. The photography is excellent and the example gear is in tip-top shape. The book is long on history — less on playing technique and artistis, so some may be disappointed. Discount and used copies are coming onto the market and you may be able to save a few bucks if you can’t pony up the full $60USD. Recommended.

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