Moog Synamp Combo

The Moog Synamp is a five unit rackmount keyboard mixer with built-in stereo power amp. An optional Synamp cabinet was available that contained 2x15s, 2x tweeters, and a midrange horn in a separate cabinet. These were built in the late 70s and there aren't many around. The Synamp comes with a sturdy wood case with front and back lids.

If you need a stage mixer/amp and you use a lot of analog synthesizer sounds or electronic drums, the Moog Synamp is the ideal system. It is very clean and very powerful, although the chassis weighs in at a hefty 90 lbs (but it comes with nice strong handles).

The Synamp contains four channels each with effects send, three band sweepable EQ (*not* parametric EQ as labeled on the front panel), peak LED, and level (actually gain). From here the system is quasi-modular in that the signal path is normalized but each 'module' has I/O patchpoints on the rear panel; there's a lot of hidden practicality in this system. The mixed signals goes through a bypassible graphic EQ (identical circuit-wise to the rack mount unit), to a big ass master volume knob, through a bypassible crossover, and then to the stereo power amps each with built-in bypassible compressor/limiter.

Each input channel has dual inputs but the mixer is mono; the reason for the stereo power amps is that the signal is split into low/mid and high frequencies by the crossover, thus they gave you an amp for each split. A complete Synamp system with cabinets is like a self-contained PA system. Again, the crossover is bypassible so you can pass the full bandwidth signal to the power amps.

The sweepable EQ on each channel sounds really nice, much more effective than the EQ on most modern boards. The circuitry is similar but is not the same as the Moog rackmount parametric EQ unit. The bass and high EQs are shelving filters, while the mid is bandpass. The controls are the dual concentric type with center detent at 0dB and typical center frequency. The bass and mid EQ have +/-15dB cut/boost while the high EQ has +/-12dB.

The effects buss uses a reverb tank on the rear lid of the case, and you can replace this with an external effect of your choice by using the rear panel jacks. Again, stereo effects need not apply. A front panel effects return knob controls the master effect level.

The power amps each can supply 200W into 4ohms, which is PLENTY for stage use. The built-in compressor/limiter has three settings: hard limit at +2dB, at 0dB, and compressor/limiter with 2:1 compression starting at -8dB and then hard limiting at +8dB. There are LED indicators for the compressor action per power amp, for clipping, and for DC and overheat shutdown. The compressor setting depends on the desired dynamic range and output SPL, it takes a little experimenting to find the right one. You can bypass it, but it's a nice safety device that will prevent blowing $$$ speakers. The speaker output has a relay that opens on power up/down and in the presence of amplifier overheating or extreme DC offsets. Moog Music made use of every trick in the book to make sure you didn't burn out the power amps, and that's OK in my book that it saves me $$$ in repairs.

The front panel includes a headphone amp along with a mute switch for the speakers. A big flashing red light warns you that the speakers are muted. The headphone amp is BEEFY; I only had it on two. The extra power is probably necessary if you're onstage with Marshall stacks and loud drummers.

Rounding out the package is a dB meter and a rather useless amp mute switch, which is spring-loaded and lets you mute one power amp at a time for balancing or troubleshooting.

I use the Synamp onstage with my two bands. One band I use it as a keyboard monitor with a Bose 802 speaker; the other band I use it as a electronic drum/bass guitar/keyboard monitor with the Bose speaker and a 2x15 Peavey bass cabinet. This system KICKS ASS on stage. I had electronic drums, bass guitar, keyboards, AND Moog Taurus pedals pumping through this system and it handled everything with ease with almost no clipping.

This is mid 1970s design folks, so don't expect Mackie specs. The Synamp is clean and quiet enough for the stage. The specs give an 80dB s/n ratio and a 30hz-15Khz +/-3dB bandwidth, but that's more than enough for a stage. The Synamp's saving grace is its power amp system.

I find the sweepable EQ on the input channels to be quite effective, in fact better than most modern mixing boards.

Do not use the internal crossover unless you're using the companion Synamp speakers. The crossover includes boosts and cuts that correspond with the peaks and troughs of the frequency responses of the speakers and drivers in the companion cabinet to yield the flattest response possible, thus the crossover won't be ideal for other cabinets. With the rear panel I/O patchpoints, you can patch in your own crossover with ease. I patch in my Bose 802C controller/EQ when I'm driving my Bose 802 onstage.

I've only been using it for a month, but I also got the service manual and found that Moog Music used every trick in the book to make a reliable power amp, and the assembly inside is beautiful. Of the few people I know that own one, their's have never broken down.

I'm an EE and I know a good design when I see one. I don't expect any trouble with this baby.

Moog Music is long gone. There are no custom parts or hard-to-find components inside, everything can be found at a good electronics parts supplier. There are a couple of online sources where you can order copies of the service manual, any search engine will find these for you. Since it's a basic mixer/power amp, any tech shop can service it.

I had my Synamp calibrated recently and the tech told me that the compressor and the power amp bias was way off; I noticed a big improvement, more headroom and cleaner power. Definitely a good idea if you haven't done yours in a long time or have just landed on in a sale.

I've been playing keyboards in clubs since 1979 and the Synamp sounds a hell of a lot better than those crap keyboard combo amps. It is clean and powerful and LOUD. I use a lot of Moog synthesizers and the Synamp handles these beefy synths with relative ease. It's also great for electronic drums, especially with a 2x15 cabinet and horn.

They didn't sell very many of these, probably for two reasons. One, they're really heavy. Two, they were expensive. A 1979 pricelist shows an original retail of $3900 for the Synamp, and I don't think that included any cabinets either. Today it isn't worth anywhere near that. The mixer is nothing much to write home about although the modularity is handy. The only thing of great value is the power amp. Let's face it folks, Moog Music is known for synthesizers, not for power amps or mixers.

I've been using my Bose 802 with a Crown DC300 amp for ten years; recently I've cut back my rig and wanted to leave the racks of gear and power amps at home, since I wanted to quit driving my gas-guzzling pickup truck to gigs and haul everything in my Saturn sedan. The Synamp was exactly what I needed. The Bose alone is plenty for keyboards. But when you combine the Bose with a generic 2x15 cabinet, this baby pumps some serious air! It's like your own personalized PA system.

It's quite heavy for most people but it doesn't bother me since I'm used to hauling around Crown amps to gigs. The weight also offers a deterent to theft, so I felt more secure leaving this set up overnight at a bar than I did with a small Behringer 4-channel mixer and a lighter amp. All the people I know that have had stuff ripped off lost the items that can be carried easily by one person; guitar heads, guitars, cymbals, compact keyboards, small mixers, mics, etc. The Synamp is too big and too heavy for one person to run off with. I don't worry about it getting stolen :)

If you land a used Synamp, be advised that they installed not 1/4" but oddball 3/16" jacks on the speaker outputs on one of the power amps. Moog Music did this so you wouldn't plug the wrong speakers into the wrong amp, and their companion speaker also had these 3/16" jacks and included speaker cables. Any tech shop can replace these with more common 1/4" jacks. 3/16" mating plugs are VERY hard to find.

I did not get any cabinets with my Synamp and it had been well gigged (missing silver caps on the knobs, scratches on the handles, etc). It was also missing the lids and the reverb tank, my guitar tech is trying to locate a matching tank for it. The seller had the case refinished but forgot to put the screws back on the bottom, so the case did not survive shipping. Since it was missing the lids I was planning on getting an Anvil rack for it anyway. If you rack the Synamp for gigging you HAVE to secure the thing from the bottom with six 10/32 screws or it'll shear itself off the rack rails on the first bump, as I have discovered losing the original case in shipping.

The Synamp doesn't look like much from the front panel but there's a LOT of practicality inside for the keyboard player or the electronic drummer. If you're gigging onstage, look out for one.