ARP Quadra

The software for this machine is really just an indicator to tell you what was on at the time. It will also remember the lead synth pitch intervals if you choose to tune the two VCO's to different intervals, as well as the arpeggiator status. It still is useful but in unusual ways.
You still can theoretically get a different sound based on a preset but still depending apon where the sliders are at the time. Microprocessors where still in their infancy with regard to musical instruments. I do understand it is a hard firmware to come across if you need it. Overall the unit is closer to an Omni than an Odyssey.
The unit is very straight forward with the flow charts that Arp implemented on all of their instruments. You will also discover features in unusual places and some features that you'd never discover without the manual.

Polyphony is not a problem. If you hold down all the keys they will sound. This thing is four limited but unique synths in a box. The bass synth while extremely limited produces some powerful pedal tones when you use the octave doubler.It only uses the lower octave and a half when switched on.
The polysynth section is more useful than most people give it credit for. It is sort of a synth organ. It's range extends down to where the bass section begins. The String synth is virtually the same nice 70's strings as the Omni. It uses sawtooth waves to create strings but can be switched to square wave with the hollow function. The lead synth is a dual VCO synth that uses either square waves or sawtooth wave. There is a very nice 14 stage phase shifter built in as well as a mixer section to balance all four synth sections as well as a fader to control the volume of an external input. There is a limited arpeggiator and a cool dual portamento control that you can set at different speed. You can switch from single keyboard triggering and multi triggering. There is several jacks on the back for controlling the various sections with pedals. The unit has several CV outputs for controlling other synths or having it's own signals controlled by an external synth.One of the really cool features is that the four synths have their own mono outputs for sending them to other amps/effects as well as a typical stereo left and right. I explain more about the outputs below. The keyboard action is fairly typical for an early synth and I replaced all the key bushings on mine.

The unit does have limmited aftertouch at the top octave of the keyboard that you can use for pitch bend or limited expression.This only works for the lead synth. These tend not to work real good due to the age and wear of the unit.If you send the various sections out on their own output jack you subtract the amount of sections going out the stereo jacks BUT (and this is really nice) you can use send and return cables on each of the synth outputs process each section separately and then use the onboard 14 stage phase shifter for more interesting sounds.
The bass synth when used with both the synth and string bass switches can destroy bass speakers.
The strings are the real strings that ARP was famous for. They sound wonderful with the phase shifter and perhaps a little reverb.
The polysynth is capable of nice synth brass, synth organ as well as some unual sound if you use the SH LFO modulation. The lead synth can give you that nice screaming detuned lead that Tony Banks used on some of the late 70's early 80's Genesis. Check out the Duke cd as well as ABACAB. You can tune the two VCO's to any interval you want as well as have two different portamento rates. Listen to Ozzy Ozborn's Mister Crowley or Kansas's Opus Insert. It doesn't sound like a Moog but it has it's own voice. If you want a Moog buy a Moog.
The real beauty of this machine is when you combine the sections together or use different effects on each output. I constantly find new ways to create interesting layers. The phase shifter is really a unique and powerful feature.The entire machine is much better than the sum of it's parts. I have also used the various cv outs to trigger my Arp Odyssey. I hope some company eventually does a software version of this because they are becoming very rare. I find this instrument very special and somewhat strange and beautiful.

Finding one of these is not easy or cheap and be prepared to spend a few hundred dollars getting it into shape. It is a complex beast and finding people to work on these is tough. I had mine restored and I was lucky in that none of the sliders were broken. The unit uses membrane switches which if broken are just about impossible to fix. I love this machine so it will never see a smoke filled bar or club but I do sample it. It helps to continually play these to keep the sliders free and relatively noise free. The sliders can get scratchy but working them up and down a few times usually quiets them down. Don't use anything on the sliders unless you are sure it won't harm them.
I have had a few hangs ups with the key contacts but I fix that myself.

Arp went out of business years ago so support is nonexistant. Arp made some great instruments but some horrendous business decisions.

Again this is a rare and unique instrument and I am glad to own the one I have. I own way to much gear to list including a full 88 key Korg Oasys. I have been playing for 35 years and enjoy both the newer digital technology as well as the old analog equipment. I find that most older equipment has it's own personality and while the Quadra may have been outdone by the Sequential Circuits Prophet 5 in terms of technology, it is still a very unique and wonderful sounding board. If someone was to steal it they better grow eyes in the back of their head. It would be a serious loss since this really more of a collectors item.

Pretty straightforward stuff - four synths in a single box. The poly synth is really an electric organ with an ADSR. But everything is put in front of the user in a very straightforward way.

The built-in phaser really is cool; it's one of the things I love tinkering with most. The sequencer is really an appregiator. The touch sensitivity feature can sometimes get out of whack, but it's handy for the lead synth mode.

Umm, we're not talking about a cornucopia of resources here. Really, there's the lead synth (with touch control), a string synthesiser, a synthesiser bass that sounds like a poorly-recorded Rickenbacker, and an organ masquerading as a synthesiser. Hint: run this baby through outboard effects unit - then the fun really starts. I recommend a distortion pedal on the polysynth. If you want real string sounds, get a sampler.

I noticed something funny, though, when I was listening to live tapes of my band from a number of years back. When you play any digital or sample-playback kind of synth nowadays, the sounds of course sound - well, pretty authentic! You turn on the Quadra, play the string synth, and think - well, cool but kinda yucky. But listen to how it sounds when you play in a group situation. The sounds really cut through - it's quite amazing. I could play Kurzweil strings and on the playback it sounds like a mushy pad. You listen to the Arp playing the same part and you say - wow, oh yeah, those are strings. A non-musician can recognize the sound as a string sound, right away. That's the amazing thing about many of these 1970s synthesisers - how they cut through, blend and 'mesh' with the rest of the instrumentation. Try playing a Rhodes piano and put in some Arp Quadra strings on top of it - a one-note melody line, an octave, or a simple third. It sounds phenomenal.

In sum: if you like the sound of Arp synthesisers and string machines, then this is the instrument to buy. It's very reliable. Don't expect it to do anything BUT Arp sounds, though. You will be sorely disappointed!

I bought my Quadra in 1988 for $600.00. It was mint condition. It's been banged around quite a bit over the past 16 years or so. I don't gig anymore (haven't since 1994), but the Quadra was always reliable - more so than all the new solid state stuff! Parts might be a problem, but most experienced electronics people can fix it when something goes wrong. I can't imagine how I would feel if something ever happened to it. I could loose any instrument but my Quadra and my Fender Rhodes!

You couldn't replace this machine. Like I said earlier, if you don't like the Arp sound, then avoid like the hanta virus. If you love Arp sounds, then this is the machine for you. Check out a number of videos for Genesis in the 1980s - the Abacab tours and beyond - keyboardist Tony Banks was always using one. You can also hear it on the Pink Floyd "Is There Anybody Out There" on the live version of the Wall - those huge phased strings are pure ARP Quadra. I love mine. If anything happened to it, I'd be desperate to replace it. It's the only keyboard I own - and I have a number of new and vintage machines - that I truly treasure and love (well, besides my Fender Rhodes, but that's whole other passionate and dirty love story).

Since everything is laid out you can modify multiple parameters realtime on the fly

It has four independent sections.
1. Bass - mono
2. strings-as many notes as you can play
3. poly-as many notes as you can play
4. lead - 2 vco's
It has a built in phase shifter w/ sample hold resonance

It is pre midi w/ many cv gate options

It has an onboard arpeggiator

This instrument's strength is that you can control many things realtime. Ex. you can change mult/ single trig on the lead section while playing, independently controllable portamento depth slider for each vco in the lead section (cool!). If you use the arpeggiator you can use one of the foot pedals to capture your chord (Lead section)and repeat it while leaving the other sections free to vamp!

Since this was one of the first programmable synths it did not "remember" depth settings on the faders. which meant that a lot of tweaking had to be done still while switching sounds which is why I am giving it a 9 instead of a 10

I used to gig with it. I did a lot of pitch bend which is controlled through key pressure and used to have to get the key contacts replaced so I don't use that feature anymore.

n/a

This synth has the classic Arp sound. There are some unique possibilities. To this day when I think I have heard everything it can do new sounds just keep cropping up! Eventhough it has a limited feature set compared to the individual instruments it combines, when taken as a whole it becomes its on unique instrument. When looking for an analogue instrument to solo with I still haven't found anything cooler than the arp!!

I have owned it since 1984 and never had any electronic problems w/ it!

The case is made of steel it is pretty wieldy in the flight case!!!

The ARP Quadra is a String machine on steroids. Sure it's more than that, but not much more. I remember when they first hit the market in the late-mid '70s. The Advertisment made it sound and look so cool. The little music stores in my po-dunk town never got one. I had to wait 24 years to finally get one. It sounds like a string machine with a cheesy mono synth grafted into it. The poly-synth part is nothing more than an organ with 1 vco "non-detunable" saw wave or square wave spread or subdivided across the upper 4 octaves of keyboard. The bottom octave of it's five octave "61 note C to C" keyboard is dedicated to bass synth and or strings bass synth. As for programmablity...It's not programmable ! It has the ability to memorize which parameters are on or off but not the actual value. So there's no factory presets because 75% of what makes up a patch has to be done by hand each time. The unit is very simple and easy to use. every function has a dedicated button or slider.

The ARP Quadra is a "jack of some trades, Master of NONE" with that said; The ARP Quadra is an ARP OMNI without all of the OMNI's features, It is an ARP solus lead synth 2VCO detunable, duophonic plays two notes or just one. It has a very limited bass synth. The Poly-Synth is just a bad sawtooth organ. The only saving grace is that all of these items can be played together with separate audio outs. The string synth and poly-synth share the same tone generators and is a divide down circuit just like many organs, which means if you play 49 notes you get 49 notes. The bass synth is 1 vco monophonic with a non-detunable sub oscillator. The strings bass is the same as on the Omni. The lead synth is 2 vco saw, square or 10% pulse waveforms, choice of mono or duo mode " 1 note or two"
NO MIDI but there is analog interface jacks (CV & gate) in and out for the bass synth and the lead synth. The "sequencer" is just a limited arpeggiator which only drives the lead synth. No velocity. It has a pressure sensitive keyboard which only affects the lead synth's filter/volume or pitch bend. Of the 4 synthesizers that this unit is supposed to be, none of the four has enough features or controls to stand alone.

The big question I had in my mind before buying the Quadra was, What does it sound like ?? I bought it without getting to listen to one first. It sounds like a bad '70s string machine, a whinning, cheesy synthesizer (old news program intro music) ARP mono synths were always thinner than moog, and this is no exception. When I first played it, I immediatly thought of the Crumar Orchestrator and Performer string machines of the 1970's. In a nutshell, that's what it sounds like. It's unique ! It shares a stand with my: OB-8, prophet-5,& Jupiter-6. I'm not sorry I bought it. It's colorful to look at, and nostalgic to play.

I just bought it and have had to calibrate the lead synth's VCOs for scaling, volts per octave and such. I noticed while I was in there, that it has been repaired several times in it's history. mostly power supply stuff like bridge rectifiers, 3 pin voltage regulators. This is a piece of history, ageing, delicate and hard to get parts for. Don't gig with it. Sample it and play it that way.

A.R.P. Alan R. Pearlman / Tonus is long since out of business.at least as far as making and selling parts for this equipment is concerned.

In our musical lives and careers it seems that we seek the proverbial Holy Grail of instruments. I would seem that often times we never find it. The quadra was my holy grail. I thought that if I could just find one, every sound I ever wanted would be be at my fingers. WELL IT'S JUST A CUP !....not even a good cup. it's like a "dribble cup" when you're trying to get that morning coffee and most of it winds up on your shirt. Don't waste your money on this instrument unless you're starting a museum. If it got stolen, I'd die laughing at the person who passed up stealing a prophet 5 off of the same keyboard stand. The OB-8, JP-6 & prophet 5 are each lighter than the quadra anyway.

In the sense that the Quadra's four sections (Bass/String /Poly/Lead synths) are laid out clearly and logically across its large front panel, it is very easy to use. However, unless one understands the fact that this is NOT truly a fully programmable synthesizer, the Quadra could be confusing. For example, programming and storing a patch on a Sequential Prophet-5 or Memorymoog is straightforward: the user sets all the parameters (pots, switches) to the desired positions and simply records the sound into a memory location. Upon writing this sound to memory, the microprocessor scans the pots and switches and "digitizes" them; that is, a numerical value which corresponds to the pot/switch position is written into memory for subsequent recall. Not so with the ARP Quadra! Underneath key synth parameter sliders such as filter cutoff, envelope attack, decay, etc. are membrane switches. It is these switches which the Quadra's microprocessor scans (NOT the pots), determining whether or not the switch is on or off (jumbo LED's show the status). If the switch is "off", then a preset value is given to this parameter (achieved by actual resistor substitution internally) and this non-changeable value is indicated by an orange dot silkscreened on the panel, next to the slider. This preset value is always either the maximum or minimum pot position (this varies depending on the parameter). But, If the switch is "on", then the actual physical position of the slider determines the parameter setting. So, the user must find an "optimum" panel setting of all the sliders which will allow most or all of the 16 "presets" to sound correctly. In THIS sense, the Quadra is not so easy to use....you'll never take your modern, "1,000+presets at the touch of a button" digital synth for granted again, will you ?! But, on the plus side, all it takes is a quick glance to determine what all parameter values are set to -- try THAT with your digital synth.

Playing the ARP Quadra is a unique experience. Its String and Poly sections are totally polyphonic; you can play with both elbows down and every note will come out. I've seen eBay descriptions which state that the instrument is 6-voice, or whatever -- that's total rubbish). The tradeoff for this feature is that there is only ONE filter and envelope generator for the entire Poly section (you can choose between single and multiple triggering, though...). However, there is definitely a positive side to this limitation: since only ONE filter opens, triggered by only ONE envelope, every note you play in a chord comes out at the SAME TIME. There is NO smearing of attacks or perceptible delay of any kind present here. This is especially apparant on big, two-fisted open chord voicings. This architecture gives the Quadra enourmous "punch". An agressive patch combining multiple sections through the onboard phase shifter can take your head off. It's lethal. Speaking of the phase shifter, amongst other things it has a very unique "Sample and Hold" setting which allows for changing LFO effects depending on which keys are depressed! Very cool and very expressive, indeed.
The Lead section is very fat sounding and features optional 2-voice polyphony. Contrary to many published reports, it is NOT a duplication of the ARP Odyssey (or Axxe, for that matter). Other unique and notable features include separate portamento speeds for the 2 oscillators (total fat city here, folks) and a very unusual ADSASR envelope generator (that's Attack/Decay/Sustain/Attack/Sustain/Release). Amongst other effects, this allows for some nice brass swell envelopes. Pulse Width Modulation (envelope control only) and a simple but expressive arppegiator are also featured. Aftertouch is also provided for the Lead section only, and can affect pitch (bend up), or Volume/brilliance (amplitude level and filter cutoff). The Quadra gets a high rating for features, espcially when one considers the fact that when it came out in 1978, few other polyphonic synths were offering multi-timbrality, aftertouch and built-in effects. Truly noteworthy.

Each individual section of the Quadra is great-sounding and fun to play. Combining the various sections and altering the phase shifter settings, filtering, waveforms, envelopes and triggering can put you into la-la land for a long time. I've blown whole days on ONE patch, changing parameters on the fly as a flutey, latched sequence arppegiates over and under deep, silky strings, all the while being stereo phase-shifted slowly across the spectrum. Two things about that amaze me: first, how many synth's besides a Korg Wavestation (12 years into the future) can you do that on, and second, I can't believe I had that much time on my hands back then to discover all this stuff ! Bottom line: The ARP Quadra sounds amazing, and it does this while sounding like NO other instrument. It sounds like an ARP Quadra: full, fat, animated, expressive, authoritative and transparent all at the same time. It particularly shines in the studio, where its limited programmability is not much of an issue. It has a permanent place in my studio and a prominent place in an upcoming mulititrack recording project. Its lack of MIDI and velocity sensitivity mean nothing to me. One need only find other means of expression, and the Quadra is loaded with them. I love it; any connoisseur of analog sound would.

My Quadra has seen studio use only and even though I'm an experienced tech, I would think twice about taking one out on tour. But I would gig locally with it. An ATA-approved flightcase is an absolute must! And this makes the Quadra a fairly heavy proposition. But, if you take care of it, they sound amazing through a big PA. I have found the tuning to be rock solid. But be aware that the innards of an ARP Quadra look like a lesson in how to (mis)use ribbon cables--lots of things can go wrong here. It's like buying a hot sports car. If you buy one with the additude that it's never going to break, you should buy something else. Analog synthesizers require maintenance. The ARP Quadra is FOUR analog synths in one box. You do the math ! ; -)

Since ARP is out of business, they really can't be rated in this category. I remember that when they were in business, you could get parts pretty easily, though.

Overall, I give the ARP Quadra a high rating. It is a versatile, great-sounding instrument with many interesting, unique features. I've owned many synths; this is one of the best sounding ones. About the only things that bug me about it is the lack of waveform variety in the Poly section (sawtooth and quasi-square only) and the fact that the Lead section is high-note priority (as opposed to low or last note priority). That takes getting used to and can feel weird at times. But after all is said and done, sound quality is the bottom line and this is the Quadra's strongest point. Plus, it's a gorgeous instrument to look at; very impressive. Definitely ahead of its time, like most ARP products (IMHO).
It makes one wonder what an ARP synthesizer would be like in this new millenium.

This is a partially programable analog synth. There are 16 programs which you program by unlocking a switch, changing, and then relocking. Very simple! But the catch is the active sliders go to the current location when you switch programs, so you have to be ready to change them to tweak your sounds. No MIDI, but has CV/gate inputs for interfacing to other ARP equipment.

I am the original owner of this 'board. I used it for years in a trio where I played left handed bass/right handed synth with a drummer and guitar player. It has four synths built in with a master mixer or separated outputs. The only effects are an arpeggiator and a stereo phase shifter (Mutron Bi-Phase which I also own one of). The four synths are Bass, Strings, Poly, and Lead. It appears they grafted the guts of an ARP Onmi and Odyssey together. The bass is single note, strings and poly unlimited notes, and the lead is two voices separately or on the same note. In it's day this was a competitor with the Sequential Circuits Prophet. For it's time I would rate it a 10, but compared to modern 'boards it is probably below average, so I'll split the difference.

Once you learn how the programablility works you can set up 16 sounds that you can tweak on with all the sliders. This is a large and heavy unit compared to most modern ones, built entirely of metal with leather trim on the two sides. Above the 61 note keyboard is a large panel with many touch pads, sliders, and indicator lights (all red or green). The ability to tweak on sounds with the sliders while playing makes it very expressive compared to modern 'boards with menus to scroll thru. The sounds range from strings, organ, electric piano, typical ARP lead synths, to detuned variations and blend of the four synths built in. I still have the original manual and patch sheets. There are hookups for a master volume pedal, and three sustain type pedals which can do a variety of things (hold, sustain, bend, etc.). During the years I used this as my main 'board on top of a Rhodes piano I could get a pretty good approximation of most sounds on records. Of course they are primitive by digital/sampled standards. But in the final years I used this after I replaced my Rhodes with a Roland U-20, your could always tell when I was playing the Quadra by the thick, full, spacious sound that came out. I have retired it to storage in it's anvil case, but still pull it out every once in a while for a unique studio project, or just to reminise.

When I first had the machine I had no problems finding some one to do modifications and repairs for me. After ARP folded into Fender it was difficult to find anyone who knew what it was. The main ongoing problems are a scanning chip which used to go out about every two years and affected the bass and lead synth. I ended up learning how to change it myself in about 15 minutes (like on a break) and purchased a large supply of the chips last time I needed one. I still have a box full. It's strange that on the board the chip is on it the only one with a sockey instead of soldered to the board. I guess the ARP techs knew something would go wrong. And the other issue was broken key contacts. They only seemed to break a lot when other people played and pounded on the keyboard. As an old B-3 player I never really player hard. Once out of necessity on the road I learned that a G string from a guitar was actually a sturdier replacement. Ever since then I would keep the old ones when the guitarist restrung, and cut and solder them as needed. Otherwise it was always reliable. Some of the slider tips have broken off, and I guess you could replace them, but I've never bothered, just push them by their little nubs.

As I mentioned above there is no more support by a manufacturer. I have seem some ads for vintage synth shops that mention they do repairs to ARP products.

This is such a unique 'board I can't say I ever really replaced it, just adapted to newer different equipment and changed my approach to playing. When I started using MIDI it became a secondary unit because I didn't need to play key bass so much, but would sequence instead. Every once in a while I run into someone who I used to play with or old friends who came to see me play who ask about what every happened to that keyboard with all the lights and big sound. I guess in that respect I kinda miss using it. I worked as a full time traveling musician for around 8 years making a good living with this as my main 'board. So I always considered it an investment that paid off. I got rid of a B-3 and two leslies to purchase the Quadra, and my back never regretted it. Now I have a B-3 type module in my rig, but nothing like the Quadra. If anyone is interested I would think of selling it to someone who thinks they would be inspired by a piece of analog history.