The "Let's Go" (Cars) filter sound - How?

[Mark Hammer]

I'm not a huge fan of the 80's Boston band the Cars, but their bespectacled keyboard player always came up with some nifty sounds.  One of the sounds of his that I like was the downward swept filter sound on the song "Let's Go".

Does anyone have any info on what sort of filter topography that was, or even what synth was used to produce it?  It would be kind of nice to have a guitar pedal that delivered the same outcome.  The Schaller/Kent Yoy-Yoy and the E-H Baseballs come sort of close but not quite.

[Lonehdrider]

Not positive, but it sounds like the old mini-moog, or patch cord type moogs to me. Ahh, analog synths when you had to know what a VCO and ADSR meant... Good sounds.. Oh so I'm told, I can't possibly be that old...

Regards,

Lone

[bwanasonic]

The EH Micro-Synth covers some of that territory well. With a guitar as the sound source, it's hard to get quite as thick a synth, but with all the faders up (straight, distortion, octave up, octave down) you have a pretty juicy signal to filter. Not as *vocal* sounding as the Cars track, but maybe a short thickening delay would help. Have always been curious to try the MoogerFooger Filter or Frostwave Resonator.

Kerry M

[ErikMiller]

I believe that part of the secret of the "Let's Go" sound was oscillator hard sync. Probably on an ARP Odyssey.

[piano boy]

I got a sound a lot like this on an Octave CAT synthesizer, which was a Odyssey clone with two oscillators. I synced OSC2 to OSC1, and then swept OSC2 with an ADSR (Attack Decay Sustain Release) envelope. Fairly fast attack, very little sustain, slightly longer release. The modulation amount from ADSR to OSC2 could be set, so I tuned it to sweep to a tone about two octaves above OSC1 before it started to fall. I  think OSC2 was set to a pulse waveform. I think the filter was also swept from the same ADSR, with a middlin resonance setting.

These memories are from 20 years ago, and the CAT sits in a closet in need of some major repair work. Maybe someone else has set up this sound more recently?

[R.G.]

I think you could do it with either a four-pole lowpass or a state variable driven by a suitable envelope generator.

I have a new SV design I'm working on that uses a single LM13700 to do the filter. I think I could get the envelope and the filter into a pedal sized PCB. It needs someone to prototype it though... hint, hint, wink, wink, nudge, nudge...

[SeanCostello]

Definitely hard sync. The synced oscillator is being swept downwards in frequency by an envelope, while the "master" oscillator is playing the desired pitch.

If you wanted to approximate this sound using more conventional tools, run your guitar through a highly resonant envelope filter, & then through a fuzz box. The sweeping filter sound through a good fuzz produces a sound very similar to oscillator sync (a good tool for minimal synths like the Roland SH-101).

Mind you, oscillator sync works well with guitar. You would need a VCO with a sync input, an envelope follower or two (or a way of having the input amplitude trigger an envelope), and a VCA. The guitar signal fed into the envelope follower. The output of the envelope follower is used to sweep the frequency of the VCO, while the unprocessed guitar signal is fed into the VCO sync input. This forces the VCO to lock onto the frequency of the guitar signal, while the envelope follower changes the "duty cycle" of the waveform (which will probably be several cycles of the VCO for every cycle of the guitar waveform). The output of the VCO is fed into the VCA, and the VCA gain is controlled by the envelope follower. This way, the VCO output will be muted when the guitar is quiet - otherwise, you will probably get some fixed tone in between guitar notes.

I've set up a patch similar to the above in Reaktor, and it works well. It acts like a fuzz box, in that you get intermodulation when you play chords, but otherwise it can nail that "Let Go" sound.  You may want to lowpass filter the guitar sound (using a fixed filter) before feeding it into the sync input, so that the sync will track the fundamental more strongly.

Sean Costello

[Rodgre]

Yep, Hard Sync.

It's not the same, but it's similar: try Tim's Uglyface. It's a similar principle, and a similar effect.

I might have mentioned this before, but I'm involved with a series of shows in my area where we put a backing band together to learn some fifty songs of one (or in this case, four) artist(s) and we have 30+ singers from the local original scene to come up and do songs. The next one is June 26 and will be THE CARS, BLONDIE, ELVIS COSTELLO and CHEAP TRICK. and we're doing Let's Go!

(www.luckydogmusic.com should have more info)

Roger