EMC Electronic Music Corporation Info Requested

EMC made some interesting gear during the 70’s… and had something truly amazing, a lifetime guarantee! Of course being they went out of business prior to 1983 the lifetime part ended up being pretty short.

The S300 Guitar Amp had the following specs:Image

  • 125 Watts RMS
  • 5 band EQ
  • Reverb
  • Portable.. yep, it only weighed 90lbs!


EMC was located at

21819 Royalton RdImage

Cleveland, OK

Per google maps, the current building at that address is huge. Either they were really that big, or they just rented a portion of said building.



Beyond the S300, they also had a G200 and a line of PA systems.

In my first band, we had a EMC Gemini PA system, it was a 6 channel unit, and it had to 2 columns with 4 eight inch speakers in each one. It sounded ok, but when we paired it up with some homemade clones of a Peavey SP3, it could really rock.





Granted, such a unit was of no comparison to the next group I was in where we had 4000Watts triamped, and 4 speaker columns reaching nearly 15 feet high… yet, for the average bar or small club, the Gemini did a super great job.

93 thoughts on “EMC Electronic Music Corporation Info Requested

  1. Hi Ron – That sounds like an ambitious project you are working on. I figured a lot of those models would have similar parts or even share whole circuit boards in common. My Sagittarius is in storage – I will have to dig it out. As for the sound, I just remember it never sounding very sweet on the top end – like you could dial back the treble to smooth it out a little but then it was too dull. It had a brittle quality which may have been associated with crossover distortion – I am thinking the early SS amps were biased cold to help prevent them from melting down? I should get mine out and see if it even still works!

    Any info you come up with will be most appreciated!


  2. EMC stereo pa-800 looking for info on it.. and if anyone is wanting to buy it u can call me at 417-255-9618..

  3. Hey all, I have an EMC B-110 bass amp and know nothing about it. What kind of amp is it? I can’t see any tubes, but it has a fuse (???). When I play it for about 10 minutes, it starts to crap out and then it dies, but it sounds great for those ten minutes. Any idea what the heck is going on? Thanks!

  4. I just found a amplifier for guitar EMC S110 it’s very clean and have some wonderful clean sound too,i tried to find something about on the net but….nothing! can you tell me more about that???

  5. E-mailed you a Schematic for a emc 300 you thought you might be able to cross reference the Schematic to the emc gemini Pa head that I have that needs some TLC. Have not hear a word from you hope is well. I was hoping you would be able to shed some light on weather or not the Schematic where similar enough to have a tech use them to fix my Pa. Thanks hope to hear from you that everything is ok.

  6. I have just purchased an EMC Performer 1 Solid State 150.
    It has two channels with Two inputs with a three position tone switch and a volume treble and bass pot, the channel one switch has selection of;normal, bass and deep bass. the channel two selections are; bright, normal and bass. The on off rotary switch has two ON positions. It was shipped to me in just a cardboard box The stem on a volume pot broke loose in shippment but it works! And sounds better than I hoped it could. It is good to find your pages

  7. Hello I own a emc B300 just kicks all original but needs to be re-coned.. does anyone kno where I could find the schematics.

  8. Just got back from the doc yesterday… 24/7 caregiving eats up a lot of time especially when things get dicey. That being said, I do hope to get back on the Gemini reverse engineering project soon. As far as how helpful or not it will be to your tech, there is a great deal of commonality across the years and some models. I hope to get some documentation published in the very near future.

  9. The G400 uses a EPM-165 power module, one of the more common (EMC also used it for guitar, bass, and PA systems, with the only differences being the preamp and signal conditioning (reverb, graphic EQ) stages, albeit some models like the G800 used two of the EPM-165 modules with a much larger power supply. It was the second most powerful module EMC ever built. The last schematic update I could find for the G400 is from 1974.

  10. Wowzers, that gotta be an early unit, likely with a flat polished front panel as contrasted with the black ones, or the later panels which were cast!!! You have a real find on your hands.

  11. There is a fellow that sells copies for a nominal free over at ronsound. I’ve purchased a few of them, and they are pretty much just duplicates of the factory schematics EMC used to include when you bought one new. Ie, they don’t have measurement call outs, parts placements, connector schemes, such as a factory service manual or Sam’s manual of that era would provide. That being said, for the price, when you don’t have anything to work off of, they are quite the bargain. My goal is to make a Sam’s style manual for troubleshooting, and eventually recreate the engineering sheets they likely had. (The true magic of EMC guitar amps is in their use of preselected FETs on the input stage… even more so, how the parameters changed over the years as semiconductor process changed. In the early days when volume was pretty low, my guess is they were manually sorting them… which is why I’ve run into some guys wondering why the tubes on my amp are enclosed. 🙂 As time progressed, I’m sure they speced out a range, which depending on the unit you got some had magic, some were pretty awful, or worse if it was replaced with generic FETs, the sweet sound quality would take a major header.

    Once the documentation stuff is done, I plan on running a ton of EMC Fets through my curve tracer to see what the distribution is, especially so as the years rolled on. (That will be quite a ways off in the future). The other reason for doing this is to try and cross the unobtanium late 60’s early 70’s fets to a contemporary version with the appropriate sorting criteria.

  12. http://ronsound.com/index.php?main_page=index&cPath=37_82 has a B300 schematic. As far as reconing goes, some of the EMC magic might be related to the use of aluminum voice coils as well as the customized Eminence speakers they used. I tried to bid on a 4×10 cab on ebay a ways back, but the seller pulled the auction being he wasn’t getting high enough bids the day before it ended. Once I get through the amp side of things, it would be a fascinating study to characterize the actual speakers. I’d really like to find one of those rare EMC cabinets with 3 fifteens. 2 of them were direct radiators, and 1 was set up as a reflector… alas it was quite the monster 49″x26″x17″ weighing in at over 160lbs!!! I believe the B800 came with 4 such units as an option… 330Watts driving over 600lbs of speakers. Talk about monster bass!

  13. Looking at an EMC B220 bass amp, but can’t find any specs on it online. I’m guessing it’s 220 watts but I have no idea considering the S300 has 125 watts… Any help?

  14. The Leo head was made in the late 60’s early 70’s. It was marketed as a bass or organ amplifier, and was rated at 300Watts. The high end model came with 3 fifteen speakers, albeit a single fifteen or eighteen was an option. In 1971, the Leo head with 3 fifteens listed at $799, or in today’s currency just a tad over $4600.

  15. Most manufacturers including EMC played a lot of games with specs back then. In some cases blatantly overrating things, and in other cases being so conservative with the distortion specs, the amp output was more like 50% higher in comparison with another manufacturer. I don’t have a cross reference as to which amp module the B220 used.

    The B200 used a 125Watt module, same as the S300, but the B250 used a 100Watt module… To me, it makes no sense to have 2 modules only 25 watts apart. My guess is purchasing got a great deal on power transistors such that they slowly morphed the 100 watt modules to 125 as time went on.

  16. To: Ron Amundson, Would you like to see pictures of my EMC cabinet with 3 15″ C15L speakers?

  17. Absolutely! Your thoughts as to how it sounds, both upfront and also out in the crowd would be pretty cool too. Afaik, I don’t think anyones used a three fifteen combination since EMC’s. I’m guessing in part due to bass being run through the PA more and more throughout the years, but also the expense and weight of the unit… but the sound aspect has me very curious.

  18. I just bought an EMC TAURUS bass amp… this thing has original green vinyl covers and all! Sounds good and loud on my bass… but awesome with my guitar! natural breakup reminds me of Townsends live sound in the 70’s. This amp has 2 15’s and a head… great shape to have been sitting for 30 years. Can someone tell me anything about these amps? I once saw a vintage ad for EMC with Dennis Dunaway from Alice Cooper… my favorite bass player! Dennis, any memories to share? Thanks, Ron Jones

  19. I just came across an old Electronic Music Corp bass amp. Model B200. Do you have any idea how to find the age of the amp and its resale value?

  20. Hello All,
    I own and use a 3-15″ EMC cabinet in my personal studio. It sounds great with every head I’ve topped it with. Currently using a chopped Fender Bassman 10 brain with it. It’s similar in size and exterior dimensions to Ampeg SVT or Acoustic 360/370 cabs and has wheels in the rear and strap handles so you can tilt back and stroll it. The blue grills are immaculate and look really cool!
    I’ll take a few pics for you.

  21. I had a musical instrument store in the ’70’s. EMC amps were a fine product, but they did not know how to distribute or promote their products well, nor were they able to support their dealers well. They used general merchandise wholesalers, who did a lame job with them. As a store owner, I was afraid that if I put the time and money into stocking them, and doing the promotion to sell them, the money grabbing distributor’s rep would put them into the record store, next door, and the record store, 5 blocks up the street, and the all pawnshops in the city, and anywhere else he could sell an amp or 2, which would make it harder to get anything of a sold business, with this brand…and there were several different distributors that carried them. My distributor, that I dealt the most with, also carried Jordan (which also had a reputation, for blowing up, Harmony amps, and I think, Alamo (I might be wrong on that one, and had previously carried Supro, when they were in business. They just weren’t marketed as a serious amp. I had one in, to look at, and it was a really impressive bass amp, with a (or 2)15″ speaker in a reflex cabinet and a powerful head with a lot of different tones, that could be got out of it. I was also an authorized Marshall dealer, an authorized, Dave Reeves era,(Highlight Electronics)Hiwatt dealer, a Laney dealer (Klipp!), and a few other amps. If I had some assurance that my work with this brand would be protected, I would have carried it along with those premium brands. They were that impressive.

  22. I have an EMC G220 guitar amp that I cherish dearly. I’ve had it since I bought it new @ 1972. It just recently smoked. The repair man says I need a schematic if I want to get it repaired. I’ve checked Ronsound, Sam’s and all over the place. I can’t find one. Does anybody know where I can find one or how I might get my cherished amp fixed? Thank you. My email is oostricharda@aol.com

  23. Schematics are hard to come by, but its possible that other models are pretty close. EMC used many of the same components and designs throughout their product line. Ie, EMC had 5 amplifier modules that they used across 18 different amps, and within a series, often times the preamp designs were the same with only minor tweaks to component values. If you are comfortable with removing the chassis from the enclosure, and are willing to shoot some photos, I can probably identify the what power amp modules are used… from there we can cross reference to the schematics from another model. Preamp wise, its trickier, but its rare to have a problem in that area. (Short of mechanical issues like corroded connectors and jacks etc.

  24. Is this page still alive? Any interest in seeing my Leo? Other than a 3-prong power cord and the polarity switch/cap disconnected, it is original and works very well. Would love to come across a matching cab…

  25. I have an EMC G220 amp and dual-speakers in cabinet if anyone is looking to replace theirs? Works, sounds great. Its just a big’n to tote around for gigs. 😉

    Love the site and the chatter. Thanks for the information and advice, Ron. Kudos.


    I’m at mark_levigne@hotmail.com

  26. I just picked up an EMC Performer 1, 150 watt Solid-State amp and matching (i believe it’s supposed to be matching) 215 cabinet. The head is clean and has no buzzing or static sounding from the controls. The cabinet only had one 15 in it, but it’s a JBL D140F. I just bought a second D140 to match it. Does any one have info on what was originally in there? I can’t find any specs sheets or ads on this amp. Thanks, John

  27. I just bought an EMC 400B bass amp and matching cabinet. Any info available on this guy? Unfortunately the speakers have been replaced 1-15 2-10. Its got a unique sound I like, just wondering if there is anything I can do to improve the tone?

  28. Hi,
    I have a B110 in for repair with a very roasted power/output board. The only markings on the PCB are PC75P on the etch side and a handwritten 4-81 on the component side. The two big filter caps date from ’73. There seems to be zero information about this amp online. Any info would be great.


  29. I came into a lot of old original EMC schematics and promo literature. I have schematics for the front ends of all the Zodiac models.
    Also, if anyone has the Rice Krispies syndrome in these amps, I found the resistor end caps will separate at times, also, the preamp transistor in the center of the power amp drive board is responsible for a lot of this. Heat that transistor, and if the crackle goes away, there’s your monkey. Get a NTE 129, it’ll quiet it down right away.
    I just got done with a complete Aries rebuild. let me know if you need anything out there.

  30. I’m hoping some of you are still somehow following this thread several years on… Bruce if you’re out there, I would especially like your contact because I finally got to a space where I can start to work on my Sagittarius. The three PC boards in mine are: Normal Channel PC70N, Vibrato Channel PC71VR, and Driver board PC72PX. The amp uses 4 RCA 40636 NPN output transistors, I am assuming in quasi-complementary configuration, with TIP29C and TIP30C drivers. I am puzzled by the small signal devices on the two input channel boards – I think they are JFETS: CFE13049 but I cannot find more info about them. Most of the smaller devices in this amp are of what I like to call the ‘spaceship’ type (white cylindrical body with a round black dome on top). If anyone has schematics for the Sagittarius amp, please contact me at dave@toneriteamps.com


  31. Is anyone still following this thread? I would love to hear from someone regarding the Zodiac series in particular. I finally got around to reverse engineering my Sagittarius but I had to guess at a few of the values. Also I need a few knobs as mine were missing.


  32. My apologies, apparently I wasn’t getting updates as to incoming comments for some reason, so I’ll make it a point to manually check things going forward. Since I started this blog, I’ve acquired some sales info and a few schematics, which I need to scan in and update. The magic of this amp, afaik is the CFE13049, which is seemingly unobtainium. One of these days I hope to hook that up to my curve tracer and capture some data on it in hopes of finding a contemporary replacement.

    I also built a spreadsheet which breaks down the modules used in the various amps. Alas, its far from conclusive, but it does give some general guidance as to what product uses what components.

  33. I also hope this thread is still alive and Bruce is still out there! Just fired up my Aries combo for the first time in a decade. It was awaiting new speakers and fell by the wayside. Everything seems in order, but I do have a few questions…
    1- how are the knobs attached? There is a little set screw hole on the side of each knob but it doesn’t seem to accept any Allen wrench or screw driver. I don’t want to strip anything, but I have a few knobs that can spin all the way around… yet can’t be easily removed. What am I missing?
    2- Anyone know the actual output wattage? Also, in regards to the impedance… I assume the original load from the internal speakers was 8ohms, as it says the external speaker jack can be connected to another 8ohm load. Do both speaker jacks need to be used in order to go down to a 4ohm load, or is that external speaker jack simply paralleled on to the main jack? I would like to run a 4 ohm load inside the cab for maximum output if that’s safe!
    3- can I fill this amp with helium? It’s f**king heavy with an awkward shape/handle situation!

  34. @ Ron or anyone else really. I know this is an old thread but there isn’t much out there about these great amps. I recently bought a one owner 1973 EMC B250 in absolutely mint condition. I mean it doesnt have a scratch. Has the silver/blue front screen. The Amp was bought in 1975 at my local music shop a day the original owner brought it back to sell it on consignment just a few weeks ago. He said he bought it hoping to learn to play bass but never really got that far with it. So it sat in his house covered all this time. Still has the sales sticker on the back. Anywho, the speaker didn’t fair the time so well and sounds bad. I am looking to replace it but I can’t find any info on wattage and ohms. Can anyone help me so that I can bring this jem back to life? Thanks

  35. Hello ,I was helping clean out a storage rental and found two EMC HF 500 amd a three speaker cabinet.They look their age and cabinet is missing the front door but speakers look ok can somebody give some info as a few people said before I could not find anything about EMC.

  36. Hello,

    we have a G400 in for service and we need a full service manual with schematic and parts list. Is this something you can provide?? If not do you know where I might get one.

  37. Need help:
    What’s up guys. Hope y all still out there and can help me. I bought a EMC Gemini today and it’s in rough shape.. pots are horrid, rusty nobs, and I think it needs a reverb tank replaced. Any schematics and advice is welcome @Bruce @Dave @Rob and anyone else

  38. HI Ron, this Is John from NH. I posted a comment back in 2013. I have since sold the 215 cabinet. I’m now looking at a Performer I with 2 matching 215 cabinets located three towns away. Any info on the power output for the head and also what’s the minimum ohms load the head can handle. I’m assuming the two cabs are not too much.

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