Clean low powered amplifier recommendations [available to purchase new from online retailers that ship to Canada], please! :)

[mike7877]

When I was in college me and some friends would go into Radio Shack and look at all the modern electronics. I remember seeing the Minimus 7s and other small speakers. I always wanted a pair but ended up buying a Koss mini system from sears. There is a pair for sale on Offerup locally right now.

I google searched what a Koss mini system might look like from 80s-90s, and came across:

WOW. I had a Koss portable CD player back in 2000. It had the most anti-skip memory ever: 45 seconds
Besides that, WOW, those speakers. So wrong, but so right!

 

[Adaboy4z]

I google searched what a Koss mini system might look like from 80s-90s, and came across:

WOW. I had a Koss portable CD player back in 2000. It had the most anti-skip memory ever: 45 seconds
Besides that, WOW, those speakers. So wrong, but so right!

Noo! It was book shelf size never seen anything like it at the time. I can't even find it on Google. It lasted well into the late 90s until I connected some bigger speakers and fried it somehow. lol

 

[MaxwellsEq]

But, they are really horrible. No way to sugar coat it. They were great at the time for parcel shelves in cars (with brackets of course- nobody wants to get hit in the head with a Min7!), great screwed under eaves for music while BBQing or for background music in shops. I sold literally thousands- more at half price when we'd order in 100s.

I remember them - they were pretty much everywhere. And they sounded terrible!

 

[mhardy6647]

I google searched what a Koss mini system might look like from 80s-90s, and came across:

WOW. I had a Koss portable CD player back in 2000. It had the most anti-skip memory ever: 45 seconds
Besides that, WOW, those speakers. So wrong, but so right!

Pair of those here. They're... fair. Not great.
Friend of mine found 'em curbside in his neighborhood. Called me on his cell "want 'em?" "Sure."
So... they're in the basement.
They have a reasonably small footprint -- i.e., could be worse.

 

[restorer-john]

Pair of those here. They're... fair. Not great.

Are those handles on the sides (pic above) original?

 

[mhardy6647]

The Koss y'all are thinking of is this:

Koss M80

There was a surprisingly interesting 'shoot-out' test of the then-popular minispeakers in Stereo Review BITD.
see magazine page 58 of https://worldradiohistory.com/Archi...iFI-Stereo/70s/HiFi-Stereo-Review-1979-08.pdf

They didn't, unfortunately, test the Koss M80, but they test a bunch of the usual suspects from the era -- and offer some surprisingly pithy assessments of their strengths & weakness. They're relatively kind to the Miniumus-7, the very low price* of them being a big factor.

_________________
* Did anyone ever pay full catalog price for a Minimus 7? I know I didn't. One pair I bought on the (semi?) annual half-price sale, and the second pair I bought were $19.99 (USD) on one of the "where-is, as-is" sales when they made some run-time change in the model. I do still have one pair here, someplace. I gave the other pair to our daughter & son-in-law, and they do still use them.

 

[mhardy6647]

Are those handles on the sides (pic above) original?

yes. Supposedly (!) the cabinets were made by a furniture maker (company). They -- the handles, that is -- come in (ahem) handy.

 

[Timcognito]

Loxjie A30 Amplifier Review

This is a review and detailed measurements of the multifunction Loxjie A30 power (speaker and headphone) amplifier with integrated USB DAC and Bluetooth input. It was kindly sent to me by a member and costs US $159 plus $7 shipping on Amazon. The A30 sports a high resolution and high contrast...

www.audiosciencereview.com

 

[mike7877]

Pair of those here. They're... fair. Not great.
Friend of mine found 'em curbside in his neighborhood. Called me on his cell "want 'em?" "Sure."
So... they're in the basement.
They have a reasonably small footprint -- i.e., could be worse.

Nice find! The side of the road is nice sometimes.

Looking at them (and many other speakers, especially larger speakers, of the era {and before}) I'm reminded of having wondered why it took the industry so long to settle on a vertical array for drivers. Obviously woofers can be an exception if they're crossed low for a woofer, but I'm sure it was obvious to anyone doing measurements during design that drivers emitting higher frequencies shouldn't be placed horizontally!

Also, in those open baffle? speakers - are those the altec woofers from the late 30s - early 50s with alnico magnets?

 

[mhardy6647]

I won't say much in defense of the Koss CM-30, other than that they don't sound bad.

Not open baffles, no, they're 9 cubic foot vented (BR) cabinets, a re-proportioned version of a vintage Altec monitor design, and - at the time of the photo - loaded with Altec 604E Duplexes, probably from the early 1960. In my case, the stock (and none-too-great) Altec XOs were replaced with Doug Sax' Mastering Labs XOs, which were, and are, pretty darned good for the Duplexes.
Here's the cabinet design.

Billforts Audio Obsession

The only problem with the Duplexes is a rather limited sweet spot, so, with some regret, a long process of experimentation led to replacing the Duplexes with Altec 515B woofers (essentially equivalent to the woofer section of the Duplexes) and separate treble drivers and horns. Still have the 604Es, though -- you know, for a rainy day. They were, and remain, superb coaxial drivers.

On topic: loudspeakers like these (ca. 104 dB SPL @ 1 meter per 1 watt input power) absolutely require low power but very clean amplification for best results.

 

[mhardy6647]

oh, speaking of driver location on loudspeaker baffles in times gone by...

There was certainly a phase that loudspeaker "designers" went through that was marked (apparently) by simply throwing drivers at a baffle template and installing them where they landed.

as one example, I offer the (not so) redoubtable Lafayette Radio Electronics Criterion VI

So wrong, in so many ways...

 

[rgpit]

Had a pair of these Grundig "Box 50's" in the mid 70's and they sounded great. Very similar in size to the Minimus 7's. Their xovers were much more complex than the RS's.

 

[Joe Smith]

For amp, yeah, Aiyima A07 would be a good, cheap option, maybe spend up and get with the 36v/6a power supply and the 4562 op-amps. Or, for a bit more available power, you could get a SMSL AO300 (currently about $200 US from Amazon).

 

[mike7877]

For amp, yeah, Aiyima A07 would be a good, cheap option, maybe spend up and get with the 36v/6a power supply and the 4562 op-amps. Or, for a bit more available power, you could get a SMSL AO300 (currently about $200 US from Amazon).

Unfortunately that's not available on the Canadian Amazon. Would you say the AO200 is comparable (and worth ~$340CDN / $250US)?

 

[mike7877]

I won't say much in defense of the Koss CM-30, other than that they don't sound bad.

Not open baffles, no, they're 9 cubic foot vented (BR) cabinets, a re-proportioned version of a vintage Altec monitor design, and - at the time of the photo - loaded with Altec 604E Duplexes, probably from the early 1960. In my case, the stock (and none-too-great) Altec XOs were replaced with Doug Sax' Mastering Labs XOs, which were, and are, pretty darned good for the Duplexes.
Here's the cabinet design.

Billforts Audio Obsession

The only problem with the Duplexes is a rather limited sweet spot, so, with some regret, a long process of experimentation led to replacing the Duplexes with Altec 515B woofers (essentially equivalent to the woofer section of the Duplexes) and separate treble drivers and horns. Still have the 604Es, though -- you know, for a rainy day. They were, and remain, superb coaxial drivers.

On topic: loudspeakers like these (ca. 104 dB SPL @ 1 meter per 1 watt input power) absolutely require low power but very clean amplification for best results.

Very nice. Sturdy looking box, too. Even though it's large, none of the panels are wide enough to really get moving. I always brace my cabinets very well, (possibly over brace lol). Whether it's boxes I've built or speakers I've bought, they alll get the treatment. In my home theatre I have Monitor Audio Silver series (different subs), and the Silver 6's at the front I added 3 horizontal braces using nuts and bolts expanded in place / lock-tite'd. It's my favourite method for speakers up to 6". I haven't seen anyone else use the same. I don't mention them because I think your box needs more bracing, your box bracing got me thinking of bracing in general, then etc.
If your speakers were cross braced again with bolts, they'd be huge!! Definitely not cost effective - the span looks just short of 30"

 

[Angsty]

NOS Minimus 7s from my storeroom

Dang, @restorer-john, exactly how big is your "storeroom"? From prior posts, it seems more like a commercial warehouse!

I love your expertise; keep on posting!

 

[DWPress]

Lol, sorry your quest for an amp has been eclipsed by Mini 7 bashing. I have 2 pair, one in metal and the later wooden enclosure variant. The metal ones are happily cranking out background tunes under a covered deck outside and have survived 4 winters now.

Back to amp offerings - how about an IcePower 125ASX2?