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ESM-3 rehab

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I picked up a set of ESM-3's a couple years ago at the thrift store.

They had 20 bucks on the pair, so i grabbed them. Didn't look very closely at them as 20 bucks is not a big sum of money for even a cheap set of speakers.

They're right about the size of my AR4x's, but a little less in weight. Still have some good "heft" to them, but they do seem like a lighter construction cabinet than the same sized AR's.

Read up a little on them once home and they seem to be reasonably well respected for bookshelf speakers. Fine examples of "pre-buyout" Energy branded (Canadian built) speakers. Add hype seems to indicate they are patterned on "Energy Pro 22's" which seem to be respected monitor speakers.

The few "testimonials" I can find online seem to be pretty "glowing", several mentioning low end response. They are a ported box, which in my experience makes speakers kind of "boomy". I tend to prefer tighter sound from my bass response. I guess I'll see if these are "boomy" or capable of nice lows without that "boominess" I've come to expect of ported designs.

So it seems they're worth the couple bucks (and my labor) it will take to rehab them. Who can't always use another project?

Pop the grills off and the woofer surrounds drop out on the floor pretty much as dust. Ok, not really that unexpected. I meter the woofers and tweeters to make sure the coils are not damaged and they come back as good. Must have been sitting idle somewhere for a while and either the sun or time has just crumbled the foam.

"Audiodogs" in BC has the proper "filleted" foams for not a lot of money, so I order up a set.

Then life got in the way and they got shelved for the past two odd years.

Now I have the time to get back on them. Woofer comes out of the first cab and there's a "brace" from the rear of the cab to the back of the woofer:


First time I've (personally) seen that. I guess it's meant to help cut down on resonances? Dunno.

Nice layer of fiberglass like fill in the case.

No cap in the crossover, just a ceramic resistor and a coil. That's another new one on me as I'm used to at least seeing a capacitor in there somewhere before the tweeters.
I may have to read up on crossover designs to see if a cap is beneficial to add to this one. Vintage speaker drivers are hard to come by and I don't want to leave these "hanging out in the breeze" should there be an audio spike of some sort fed into them accidentally.

And while I know it's generally "controversial", I may look at fusing them as well. Potentially giving up a little SQ is worth it if it gives "unobtainum" vintage drivers a better chance at longer survival. I recently had a set of AR4x's "pop" their tweeters and it's proving to be a bit of a nightmare to source replacement originals, so I'm fine with accepting some limitations to protect drivers from a "mistake".

Start cleaning the first woofer:
Poly cone so it's relatively easy to clean. IPA seems to soften things up nicely. There's still a fair bit of work to do to them, but nothing overly difficult. It's just patience and time.

The mesh dust cap is interesting. That's new one on me too.

Taking a break from the grubby work of cleaning the woofers, I give the grills a clean:
 They had the typical 40 years of dust and dirt splatter on them and they clean up pretty nicely. They still need a few more rounds of cleaning, but I want them good and dry before going at them again. It's audio mesh over particle board, so too much "wet" all at once is not a good idea.

One grill has a small "rip" in one corner, but it's on a bottom outside corner, so it's not really visible when installed. I'll probably black out the bit of wood material showing and use a little "rip stop” product to bind the edges and keep it from getting any bigger.

The grills are also missing one of the "ESM" badges. Not sure what to do about that as I'm never going to find another one. the one that's still there is just plastic, so I may make another I can print out on the 3D printer and paint to match.

The veneer also looks very "thirsty, so I give "Howard's Restor-a-Finish" (neutral) a try:
Not bad, but that wood was some thirsty. Sucked it right up and after a light rubbing with a clean cloth, the veneer looks quite respectable. There's still the odd light scratch here and there, but nothing that jumps out at you. They're 40 year old bookshelf speakers, so it's not unexpected wear of any sort, These actually must have lived a reasonably comfortable life compared to what usually happens to speakers at this end of the market spectrum.

You might think these would be vinyl coated cabs, but they're not. that's a wood veneer over that particle board (or whatever type of composite board it is).

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One freshly glued and one partially dried:




Used Aleene’s for the first time. Guess I’ll see if it lives up to its rep. Was easy to use and position surrounds for sure.

Fed them both a 30hz signal after initial positioning and all seems good to go.

I’ll give them a good 12-24 hrs to fully cure and then back into the boxes they go for a "test run"....

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On 3/7/2024 at 4:00 PM, tourmax said:

IPA seems to soften things up nicely.

Yeah. Beer softens me up too 😄

On 3/7/2024 at 4:00 PM, tourmax said:

The mesh dust cap is interesting. That's new one on me too.

Your 4x's have a mesh cap, essentially.

On 3/7/2024 at 4:00 PM, tourmax said:

The veneer also looks very "thirsty, so I give "Howard's Restor-a-Finish" (neutral) a try:

That should clean it up nicely but if the wood is thirsty, Howard recommends following up with their Feed n Wax.

On 3/8/2024 at 11:52 AM, tourmax said:

Used Aleene’s for the first time.

I use Aleene's on paper cones. Don't know how it will be on poly. I use that nasty nitrile based glue for plastic cones.

Looking forward to more posts. Not familiar with that brand but those seem very nice. I think in general Canadian speakers are quite good. I'm told the Canadian government helps speaker manufacturers with R&D. I'd say they were a great find and a good project.


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They’re done and I’ve used them a bit. 



they sound nice, perhaps just a touch of “boom”, which I’m accounting to the port in the box.  Nothing objectionable, just noticeably different from the AR’s sound.
The ar4x’s are a bit nicer sounding, a little bit smoother and more “accurate”, if that makes sense.

Plan is to put the esm-3’s up in my hobby room, paired with a Pioneer sx-680 I’m currently rebuilding:


35wpc should pair nicely with these. The 680 has a blown output, which is fairly common on these. The “darlington power amplifier” IC is no longer made, so I’m first going to try an “eBay special” and if that doesn’t work, I’ll build a discrete component network to replace the stk0039 component. There’s even “kits” available for this on eBay, although the kit (ie: builds two stk0039 replacements) alone is worth more than the little 680 will ever be worth. 

I have a fairly “mint” pioneer pl-200 semi auto turntable:


and a Sony 5 cd carousel player to go with them as well.  

Nothing “high end”, but will work just fine for casual listening chores while I’m tinkering with something else (ie:hobby).

Canadian speaker manufacturers were given access to the NRC facilities, which, among other things, had an audio/sound research lab that was world known at the time. The program was part if a larger program and put in place to help the Canadian audio industry compete on a world stage. Basically, it was intended as a gov’t sponsored “boost” to the overall economy by trying to “bring up” all market segments. Its just so happened that Canadian audio company’s also benefitted largely from the program and accessing gov’t sponsored research facilities.

here’s a little info in it:


ignore the add hype in the write up. The NRC stuff is accurate though.


I don’t think NRC is involved with the audio industry in Canada any longer because, well….there’s really no audio industry here anymore. Everything is like everywhere else these days: once storied and respected brands bought out by conglomerates and cheapened down to the lowest possible extent to maximize profits. Energy is still around, but foreign owned and they make cheap things like bluetooth speakers, bug zappers, etc. 

Sad, but its the way the world is now….


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Nice work. Enjoy the music.

I remember commenting to my audio technician friend that it was my impression that all Canadian hi-fi was excellent. He said "well, not ALL...." He named a company but I've forgotten the name. Electro-something? He said it was an attempt by the gov't to re-train lumberjacks to build audio equipment. Apparently not high quality. Sounds like a Monty Python bit to me 😄

I've always lusted after Bryston gear but never took the plunge.

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