MK S-80 Satellite Speakers Review: Classic High-Fidelity Sound

Discover the legendary MK S-80 Satellite speakers from Miller & Kreisel, known for unmatched clarity, dynamic range, and studio-quality sound in a compact design:

The MK S-80 Satellite speakers are a celebrated example of Miller & Kreisel’s commitment to high-fidelity sound in a compact form. These 4-ohm speakers are well-known among audiophiles for their incredible transient accuracy, wide dynamic range, and transparent midrange—making them a favorite for both music and home theater setups.

Despite their small size, S-80 Satellites deliver precise, uncolored sound, excelling at reproducing the true character of both recordings and live performances. They were engineered with phase-coherent crossovers and matched drivers, resulting in balanced imaging and linear response—qualities that help the music shine as the artist intended.

Early M&K systems like these set the standard for pairing satellites with subwoofers, ensuring the speakers focus on accurate upper frequencies while leaving deep bass to a dedicated subwoofer.

The S-80 speakers offer tunable inputs—High Efficiency or Low Efficiency—allowing users to optimize tonal balance and volume depending on their amplifier and listening space. Power-hungry by design, they reward pairing with a quality amplifier and careful setup. Overall, the MK S-80 Satellite speakers carve out a special niche for listeners who value detailed, honest reproduction—bringing a studio monitor ethos into living rooms everywhere.

Posted in Speakers, Vintage Audio | Comments Off on MK S-80 Satellite Speakers Review: Classic High-Fidelity Sound

USHER S520 mini-monitor speakers / A British speaker out of Taiwan ?

I picked these up for $300 with stands in the local market place. For the piano black finish, I saw a pair for about $700 with shipping and tax on ebay, and these came with stands too which I will sell for $100 to get my total price down to $200 which is not too shabby.

Being an audiophile for about 10 years, I have heard not all, but many good speakers and many British ones that I also own, and the mid-range is just beautiful with not excessive, but good tight Bass! It can use a good sub-woofer to help fill the low end, but please use a good one, made for music, mine is a EPOS ELS Subwoofer and they pair magically good!

I was and am still impressed, this will stay in my collection!

The Usher S-520 was co-designed by Dr. Joseph D’Appolito (USA) and founder Tsai Lien-Shui (Taiwan). The model was directly inspired by classic British mini-monitors, with the build and voicing modeled after the famous BBC LS3/5A and Celestion 3—renowned UK speakers known for their compact form factor and musical accuracy.

Design and Modeling Inspiration

  • The S-520 is explicitly a homage to British studio and consumer monitors, specifically the LS3/5A and small Celestion and Epos speakers.
  • Its sound signature—lush mids, precise imaging, and compact, rigid cabinet—draws from British engineering ideals: neutrality and musicality over exaggerated bass.
  • The proprietary “Symme-Motion” driver design (with careful attention to suspension and magnetic symmetry) was developed specifically for this monitor by Usher, not copied from a particular UK driver, though the sound target is the British mini-monitor tradition.

Drivers

  • Uses an in-house Usher-designed 5″ polypropylene woofer and a 1″ silk-dome tweeter made in Taiwan but tailored by D’Appolito for the S-520.
  • The crossover was also tuned to British standards for phase and tonal accuracy.
  • These designs were not licensed from British companies but come from Usher’s own manufacturing, aiming to replicate the appeal of iconic UK monitors for a wider audience.

British Speaker References

  • Directly compared to and modeled after the Celestion 3 and BBC LS3/5A in reviews and technical discussion.
  • Several reviewers and designers note the “British sound” of the S-520—focused, revealing, and musical.
Posted in Speakers | Comments Off on USHER S520 mini-monitor speakers / A British speaker out of Taiwan ?

fixing HEX heat exchanger error on original PICO Brew machine

One of the things that I like about these machines is that they are fairly accurate and brew good consistent repeatable beer, as long as your recipe is sound… and sure while their later models are better like the Z1, these are still sound machines and worth keeping and brewing.

One of the most common type of error that you will get with these machines is a HEX error, where basically there is air trapped in the heat-exchanger, and the temperature sensor will detect a big temperature differential and the machine will start to make noise and the program will end, this will happen fairly fast once you start a Brew program.

I was told that in the beginning the company just put water into these units, but the machines would freeze in colder climates, so later they changed to using glycol. I just used water, but some people prefer glycol. Botton line is, if water/gycol ever leaks out and air gets introduced into the HEX, the error will come back. The Z1 machines have the pumps and all at the top of the machine, so it is much easier to get to it, you just remove the top and you have much quicker and easier access to it, but with these original machines, the pumps, boiler and heat-exchanger are actually at the bottom of the machines.

I am attaching a doc that was shared with me from the FB Group:

https://kodiakbrewing.com/wp-content/uploads/2025/09/Zymatic-Glycol-Loop.pdf

I’ve also recorded some of it when I was actually working on it and here that YouTube video:

cheers!

Posted in Beer Brewing Equipment | Comments Off on fixing HEX heat exchanger error on original PICO Brew machine

B&K Ex-442 Amplifier – Power PCB Upgrade Boards now available!

My main amp of choice right now is the B&K Ex-442. I have upgraded the main filtering caps to brand new ones and even upgraded the rectifier Bridges to support higher inrush currents better (yes, I keep the old parts).

But one thing always bothered me, and that was the power circuit PCB board that sit on top of the filter capacitors, there is two of them, one for each channel as this is a dual-mono block in one box design with a shared toroidal transformer.

Also, these are the types of moments that really lead to new opportunities, because this is not the first example! Like creating a 3D baffle for the EPOS ES-14 because the original tweeters fried.

So this got me back into the game of CAD design, I used to make these by hand when I was a kid, so I never used any software.

The software of choice, I wanted that to be open-source / and it if is good enough, I will use it, I am tired of jumping through corporate hoops for Corporate products with their licensing and any possible change to what they offer, even free community versions.

Anyways with that I used KiCAD, and yes there was some learning curve, honestly there isn’t many good videos on YouTube for beginners, or at least I couldn’t find any. So in this case, I actually used AI to help me… and by that I mean, you know: How do you do this, how this and that and how to you change that, after about 7-10 questions and try and error, I had all the knowledge to do this.

I eventually also met with another KiCAD user who showed me around a lot and the ropes of KiCAD and that is to understand the relationship between the Schematic and PCB modes, as these are highly related.. his Blog is here: https://lensprojects.com/

Video of Install:

and Video describing the boards specifically new vs. old..

Contact me, if you want these – https://kodiakbrewing.com/contact-me/ Cheers! Ray.

Posted in Vintage Audio | Comments Off on B&K Ex-442 Amplifier – Power PCB Upgrade Boards now available!

Chario Piccolo Satellite Speaker

Recently I have acquired some new to me Brand of speakers – Chario, model is Piccolo which are small satellite speakers… The are hand made in Italy (whatever that even means), and sounds very good for their small size, below is a sample of their capabilities…

To be honest, even those these are very good speakers, they just didn’t have enough magic for me and I sold them, stick to my trusty EPOS 🙂

Cheers!

#chario #piccolo

Posted in Vintage Audio | Comments Off on Chario Piccolo Satellite Speaker