This 1948 230K doesn’t look like it’s been in service for nearly 80 years
In the early 1900s, Hawaiian music captivated America. With the advent of electric amplification, the electric lap-steel guitar fit right in with the sound of Hawaiian music in the 1930s and ’40s. The guitar amplifiers you heard on these early electric recordings were straightforward and low-wattage, designed to simply project the sound of the instrument.
This 1948 Oahu 230K is a great example of the warm, natural sounding amps that were produced during the first half of the 20th century. The Oahu Publishing Company was founded around 1930 in Cleveland, Ohio. The company published primarily Hawaiian sheet music and music lessons, and eventually also sold lap steels and accompanying amplifiers. This is a beautiful example of the 230K, with very little work done on it previously.
There are a few versions of the “Tonemaster” 230K, coming in different shapes and colorways. Amplifiers from this era often have memorable designs with rich color schemes and textures. This amp is one of my favorite versions of the 230K, with caramel and cream colored Tolex. The grill is velvety soft, with sentimental lettering and a classic music note design. One of the very first amps I ever took apart and studied on my own was the slightly later version of the 230K, which had a shield-shaped grill. Talk about nostalgia!
The inside of the 230K shows a simple, straightforward circuit.
This “Tonemaster” amp sports a 12" Rola field-coil speaker, date stamped for September of 1948. It has an instrument channel with two inputs, a microphone channel with one input, and a tone control. In this version of the circuit, the amp uses a 6SC7 for the first gain stage and a 6SL7 driving the pair of 6V6 output tubes. The amp also has a 5Y3 rectifier tube.
The amp came to me with a 2-prong power cord and no modern components in sight. Someone may have replaced some of the main filter capacitors in the ’60s or ’70s. The filter capacitor can was disconnected and individual orange Astron capacitors took their place in the power supply. This amp must have been well kept, as the outer Tolex and inner circuitry is extremely clean for its age. The grill is impeccable with virtually no blemishes. I find myself wondering about life in 1948 when this amp was built—almost 80 years ago.
As is typical for amps of this age, I needed to install a 3-prong power cord. The hot and neutral wires literally disintegrated when I cut them out! I also needed to replace the electrolytic capacitors for safety and reliability. For me, there is no question—the power supply needs to be refurbished if the amp is going to be used. Once this preliminary work was done, I tested the amp for a while. During this time, I listened for any abnormal hissing, crackling, or other noises. Unsurprisingly, the idle noise of the amp turned into sporadic crackling and popping, which led me into phase two of the repair.
To track down noise issues like this, I will pull one tube at a time, starting with the first preamp tube in the circuit. When I pulled the first tube, the 6SC7, the noise was eliminated. This told me that the noise was being amplified by this first gain stage, and the cause lies either before or within that first tube position. I grabbed a NOS 6SC7, installed it, and no more noise! In this case, the issue was simply the tube itself. If there was still crackle with the new 6SC7 installed, I would suspect another component in the circuit.
I noticed that the microphone channel’s volume pot was totally frozen, and it was difficult to turn the control in either direction. This was likely caused by oxidation or corrosion over time. Sometimes, treating and cleaning the potentiometer will help to get it moving, but this one was pretty extreme. I grabbed a new 1M potentiometer and replaced the seized pot. Good as new!
With the amp fully functioning, I was finally able to enjoy some quality time playing through it. This amp was built shortly after the end of World War II, when America was gaining an optimistic spirit and the popular music of the time was emotive. Simply strumming the guitar through this amp at low volumes felt cozy and nostalgic, like wrapping the guitar sound in a warm hug. This is a roughly 10-watt amp, and when the volume gets cranked, the amp growls with that natural tube overdrive. While music at the time did not call for distortion in the guitar tone, it is a welcomed characteristic that is prevalent in many amps of the era.
Boutique pedal mastermind Mr. Black has launched the Stereo Vintage Ensemble Pro Chorus pedal.
Building upon the legacy of the original 2015 Vintage Ensemble, the Stereo Vintage Ensemble Pro re-defines what a true-stereo chorus is capable of, delivering classic 70’s chorus tones plus a magical spatial-enhancement algorithm which builds a three-dimensional modulation field that emerges everywhere as it elegantly glides about the room.
Modern amenities like tap-tempo, external expression pedal input, a suite of presets and full MIDI support round out this vintage-voiced powerhouse.
Hand built one-at-a-time in Portland, Oregon, the Stereo Vintage Ensemble Pro doles out truly vintage vibes in a compact and handsome package.
Key features include:
Stereo vintage-chorus with spatial expansion
Very wide range of LFO speeds with Tap-Tempo
Stereo inputs and outputs
Expression-pedal input
Nine total presets
Full MIDI support (MIDI Type-A)
Powered by “Industry Standard” 9VDC
The Mr. Black Stereo Vintage Ensemble Pro carries a street price of $299.95. For more information visit www.mrblackpedals.com.
Dunlop has introduced a special Cry Baby Wah to celebrate Iron Maiden’s Killers album. Designed in collaboration with the members of Iron Maiden and featuring the classic tones of the GCB95 Cry Baby, this collector’s edition pedal pays tribute to one of the world’s most influential bands.
Emerging from the rough-and-gritty streets of late-’70s London, Iron Maiden met the world with galloping rhythms, steel-forged riffs, and banner-raising vocals—and they never stopped. Their intricate multi-guitar melodies and unmatched vigor helped define heavy music, and the band remains a fixture of the genre. The Cry Baby Wah was integral to the momentous album Killers, escalating the tension and deepening the dark grittiness of tracks such as “Wrathchild,” “Innocent Exile,” and “Drifter.”
This collector’s edition Iron Maiden Killers Cry Baby Standard Wah celebrates that sonic connection with an exclusive collector’s edition finish and custom tread inspired by that record. Whether it’s mounted on your pedalboard or standing at the heart of your shrine, this pedal is a torch held high for rock ’n’ roll. Join us in saluting one of the most powerful and enduring forces in music history, and get your hands on the Iron Maiden Killers Cry Baby Wah.
Iron Maiden Killers Cry Baby Wah highlights:
Exclusive collector’s edition tribute to the powerful and enduring Iron Maiden
Custom tread and finish inspired by artwork from the momentous album Killers
Featuring the bold and expressive tones of the GCB95 Cry Baby Standard Wah
Da Capo, an imprint of Grand Central Publishing (GCP) and the Hachette Book Group announce the publication of IN MY DARKEST HOUR: A Memoir by Dave Mustaine with Joe Layden on September 8, 2026. “In My Darkest Hour is Dave Mustaine at his most revealing, vulnerable, and true,” stated Ben Schafer, Executive Editor, Da Capo. “With lacerating honesty and soulful reflection, he speaks to the universal human experience of facing serious illness and how it changes a person, their family and friends, and one’s relationship with creativity. Da Capo is proud to publish Dave Mustaine’s most unblinking memoir to date, one that isn’t only for Megadeth fans.”
“One of most harrowing experiences of my adult life has been my seven-year journey through cancer treatment and onward into remission,” Dave Mustaine says about the experiences detailed in the forthcoming book. “This story is considerably more than just go to the doctor, get diagnosed, get treatment and hopefully I live happily ever after. This was a journey of me saving myself, staying alive, keeping my family together, and continuing to make music through it all."
Dave Mustaine is no stranger to pain and suffering. He battled demons all his life—including an alcoholic father, addiction, and black magic—and turned fifty-eight believing he’d survived the worst. But in 2019, Mustaine was forced to face the loss of his instantly recognizable voice and the disintegration of his musical talent. Diagnosed with squamous cell carcinoma at the back of his tongue, his entire career—and possibly his life—was about to end.
For Mustaine, it was one more opportunity to fight like hell.
In My Darkest Hour takes readers from the treatment room to the studio as Mustaine chronicles how his diagnosis inspired him to take up the pen and guitar pick, going from radiation and chemotherapy appointments straight into hours-long recording sessions, resulting in Megadeth’s sixteenth studio album, The Sick, The Dying…and the Dead! Along the way, Mustaine details how confronting his own mortality brought him closer to his family, taught him how to ask for help, strengthened his faith, and challenged the vulnerability of his art.
Filled with perseverance, hope, and the determination to never let the bastards grind you down, In My Darkest Hour is a masterful portrait of a Dave Mustaine that the world has yet to see, and serves as a moving reminder that even our most invincible heroes are human.
Now, six years removed from that initial diagnosis, Mustaine is seeing the biggest success of his 40-plus-year career with Megadeth’s final studio album and tour. Committed to go out on top, Megadeth’s new album (released in January 2026) debuted at #1 on the Billboard 200 in the U.S., marking the band’s highest debut week ever on the chart. Around the world, the album garnered critical acclaim and hit #1 in 11 countries and landed Top 5 positions on 11 additional charts.
“Caught In The Echo,” the third song to be released in advance of Foo Fighters’ forthcoming 12th full-length studio album, Your Favorite Toy, is now available across digital platforms.
Following in the turbulent wake of the album’s postpone-tinged banger of a title track — described by THE NEW YORK TIMES as "back-to-basics garage-rock delivered in a welter of noisy guitars” and moving VICE to rave "Unhinged Dave Grohl is my favorite version of Dave Grohl” — “Caught In The Echo” is the instantly combustible opener that sets the tone for the harnessing of the FF live fury that pervades the album. From its opening exhortation of “Do I? Do I? Do I? Do I?” to its closing plea of “Who can save us now?”, “Caught In The Echo” foreshadows the new album’s rough hewn energy with arguably the band’s most explosive opener since Wasting Light’s “Bridge Burning."
Your Favorite Toy will be released April 24th via Roswell Records/RCA Records. Recorded at home, the album was co-produced by Foo Fighters and Oliver Roman, engineered by Oliver Roman and mixed by Mark “Spike” Stent, and consists of the following songs:
Caught In The Echo
Of All People
Window
Your Favorite Toy
If You Only Knew
Spit Shine
Unconditional
Child Actor
Amen, Caveman
Asking For A Friend
Your Favorite Toy’s release heralds Foo Fighters' massive Take Cover world tour, which just added an already SOLD OUT April 28 show at the Total Mortgage Arena in Bridgeport, CT. For more information on the rock ’n’ roll stadium tour of the summer, go to https://foofighters.lnk.to/ShowsPR
Last but not least, running errands in the San Fernando Valley became a lot more interesting yesterday, as 20 personally burned CDs of “Caught in the Echo,” each featuring individually hand-drawn artwork by Dave and Harper Grohl, were hidden in various locations in the area, ranging from local indie record stores to national grocery, book and pharmacy chains and more. For updates and further information on the “Caught in the Echo” scavenger hunt, check https://www.instagram.com/foofighters/
Foo Fighters are Dave Grohl, Nate Mendel, Chris Shiflett, Pat Smear, Rami Jaffee and Ilan Rubin.
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