Dr. Harvey C. Rentschler: Unsung Hero Of The Post world War II Electric Guitar Revolution?

Even though his work is largely devoted to energy efficient UV lamps for zapping dangerous microbes, does Dr. Harvey c. Rentschler’s other discoveries pave way for the post World War II electric guitar playing revolution and Rock N’ Roll?

By: Ringo Bones 

Unlike Albert Einstein, Dr. Harvey C. Rentschler never became a household name for much of the 20^th Century, and yet without his important discoveries, contemporary popular music and electric guitar playing after World War II would have been very different. And music recording via mixing desk like those in the iconic Sun and Abbey Road studios would never had existed without his discoveries and the world would also had never heard of Elvis Presley or The Beatles without his discoveries that led to the more efficient, smaller and cheaper thermionic vacuum tubes. 

When he told his findings to a meeting of the American Physical Society which was then published in the July 1943 issue of the Scientific American magazine, Dr. Harvey C. Rentschler told the attendees about what he had found out in experiments which he conducted eight years before. It led him to conclude that atoms of gas – oxygen, hydrogen or nitrogen – actually dissolve in the crystalline structure of some metals just as salt dissolves in water. These gas particles then “loosen” the electrons in this structure, causing them to be emitted from the metal more readily when heat is applied. This explanation, according to Dr. Rentschler, should result in longer-lasting thermionic vacuum tubes and accomplish important savings to the size and number of batteries, generators and other apparatus needed to supply the filament power. 

Without discovering the then unknown principles that led to the advanced thermionic vacuum tube design principles that led to smaller, more energy efficient thermionic vacuum tubes by Dr. Rentschler, Rock N’ Roll would never had existed and electric guitar playing would be a rather expensive hobby dominated by large inefficient vacuum tubes and ultra-expensive gear the average kid from the 1950s could never afford. Dr. Jim Marshall would probably use something else entirely when he developed his now iconic Marshall Amplifier back in 1962. Thanks to Dr. Harvey C. Rentschler, we have 12AX7 preamplifier tubes that can operate with anode voltages as low as 45 volts DC – making the now 48 Volt DC phantom power de rigueur in the modern post World War II recording studio when Les Paul invented it. 

Paper Coned Loudspeakers: Electric Guitar Speakers?

Despite advances in hi-fi loudspeaker cone materials in the 1990s, does paper coned loudspeaker still mean electric guitar speakers like Heinz means catsup? 

By: Ringo Bones 

Since the heyday of Les Paul to recent concerts of Yngwie Malmsteen or Joe Satriani that still attract hoards of electric guitar music fans, it seems like the paper coned loudspeaker – especially ones with a whizzer cone and seems to have dated back to the early 1920s – had been exerting a stranglehold on the electrical musical instrument industry as the only musical instrument loudspeaker suitable for electric guitar playing use. But how did such a self-made paper coned loudspeaker empire came to reign over the electric guitar playing world? 

Guitar virtuoso Yngwie Malmsteen may have recently endorsed paper coned loudspeakers as the only ones suitable for serious electric guitar use. A recent “tone testament” by Malmsteen on the paper coned Celestion G12T-75 speaker shows his praise for its fluidity and praises its violin-like tone sustain and feel that compliments his style of guitar playing only reinforces the facts – and preconceived notions -  surrounding paper coned loudspeakers use in the electric guitar playing world. Boutique Marshall electric guitar amplifiers that use their exclusive paper coned Sheffield speakers still further reinforces the perception even more. 

Enthusiasts in the audiophile world who are heavily into rock music are not helping much either. Retro-looking hi-fi loudspeaker systems made in the 1990s like that by Lowther that looks like it dates from the early 1920s with its horn-loaded paper coned alnico-magnet equipped loudspeaker with a whizzer cone are often praised for its realistic rendition of late 1980s electric guitar heavy hair metal era heavy metal music. Given that electric guitar and hi-fi speaker system for playback both use paper coned loudspeakers - it is safe to assume, and in actuality, that both seem to compliment each other seamlessly. 

Hi-fi reviewers can never be accused of being miserly in their praise for paper coned loudspeakers and their righteous reproduction of electric guitar based heavy metal music. Hi-Fi World magazine reviewer Douglas Floyd-Douglass stated in the October 1995 issue of the magazine on his review of the Wharfedale Valdus 500 that: “Lead and rhythm guitars sound excellent, which I’d attribute to the paper cones – a favorite choice used in hundreds of famous electric guitar amplifiers. Their partiality to rock was further emphasized by Richie Blackmore’s scorching lead and powerful backing on ‘Rainbow’s Power’ and Miss Mistreated’.” And high-end hi-fi manufacturer Yamamura Churchill further reinforces the mystique surrounding paper coned hi-fi loudspeakers with the use of rare paper from Japan made from select bamboo pulp as its “magic ingredient”. Given the dominance of paper coned loudspeakers in the electric guitar and hi-fi world, how does the alternative cone materials fare? 

Around the late 1980s, an electric bass guitar amplification manufacturing firm named Hartke Systems had used metal coned – as in aluminum coned - loudspeakers to go with their electric bass guitar amplifiers. Around that time, Hartke Systems electric bass guitar amplification systems were used by Aerosmith bassist Tom Hamilton among others and many of its users say that Hartke’s aluminum coned speakers provide a big, clear dynamic sound on top with maximum punch on the bottom, though nobody tested it for heavily distorted loud electric guitar use for obvious reasons. 

Part of what makes paper coned electric guitar loudspeaker and vacuum tube amp system like Marshall’s have a “musically desirable” tone is due to the fact that paper coned loudspeakers act – according to the laws of acoustics – like a bandpass filter that works between the audio frequency of 75-Hz to around 6,000-Hz. Especially with a distorted electric guitar tone, high frequencies produced by an overdriven tube amp that sounds bad to our ears – and can destroy tweeters - are brought down to desirably pleasing levels via the paper coned loudspeakers inherent inability to produce very high audio frequencies. While the paper coned loudspeaker’s inability to produce lower bass frequencies below 75-Hz – as it is most often mounted in an open baffle configuration in electric guitar applications – filter the “reactance thumps” between the electric guitar strings and the pickups that can easily overload dynamic microphones in live stage miking situations. 

I’ve also experienced using first hand a mineral-filled polypropylene coned loudspeaker into electric guitar use back in the late 1980s and all I can say is – it was the quackiest mess I’ve ever heard. Unless you are doing a rock concert scene for a sequel of Howard The Duck or a quacky, parody version of Mötley Crüe’s Kickstart My Heart, mineral-filled polypropylene coned loudspeakers are only suitable for domestic hi-fi use, as they have been since the mid 1970s, when they are not played too loud. It seems like paper coned loudspeakers are the only ones that distorts in a musically consonant manner when played at excruciatingly loud levels. 

Germanium Transistors: The Best For Electric Guitar Distortion Pedals?

Even though 9-volt battery powered electric guitar distortion pedals that use germanium transistors are the best ones around, how come these types are still a rarity?

By: Ringo Bones 

Every self-respecting electric guitar wielding musician with experience knows that germanium transistor based 9-volt battery powered electric guitar distortion pedals are the best there is – as in those 21^st Century era reissues of Dallas Arbiter Fuzz Face pedals now starting to appear again in musical instrument stores. Even though such pedals are not that expensive in terms of quality guitar accessories – at around 150 to 300 US dollars each – why then are germanium transistor based electric guitar distortion pedals rarer than their silicon transistor based or even integrated circuit / IC operational amplifier based counterparts? 

The reality is, germanium transistors – which are the first of its type mass produced for commercial applications during the 1950s onto the early 1960s are not very stable and somewhat difficult to manufacture compared to more modern silicon transistors and semiconductor devices. Even during the start of the 1960s where the relatively affordable prices of transistorized radios started to capture the market previously dominated by vacuum tube based radios, germanium transistors are very hard to mass produce with consistent parameter quality. Electronic enthusiasts “toying” with germanium transistors during the early 1960s have noticed first hand that they have very variable gain, leakage, noise and overall tone – even germanium transistors manufactured from the same batch. 

The inherent parameter variability of germanium transistors means resistor values selected for proper AC and DC biasing, feedback, gain and stability that worked fine on one functioning circuit – like an electric guitar distortion pedal – will have to be “tweaked” (use a slightly higher or lower resistor value) to make one sound as close as possible to the previously finished circuit – even from germanium transistors of the same batch. Thus making the manufacture of germanium transistor based electric guitar distortion pedals a somewhat very labor intensive endeavor. 

Although, one can make silicon transistor or even I.C. op-amp based electric guitar distortion pedals approach the sound of germanium transistor types by using germanium signal clipping diodes in the feedback loop, purists still prefer the tone of the authentic germanium transistor based electric guitar distortion pedal, especially if your hi-fi system is righteous enough to realistically reproduce the guitar intro of Iron Maiden’s Two Minutes To Midnight – as in the original vinyl or the mid 1990s era Sony Super Bit Mapped CD reissue. The Sony Super Bit Mapped mastering even brought out the “germanium signature noise” on the very start of this iconic Iron Maiden track. 

The Obama Wah: The “Yes We Can” Wah?

First saw the product and its advert back in 2009, but is the Obama Wah truly qualifies as the “Yes we can!” electric guitar effects wah? 

By: Ringo Bones

More recent adverts of the said product now run a disclaimer by the manufacturer that the product is not meant to be political, but does the Obama Wah truly qualify as the can do “Yes we can!” slogan of it’s political namesake who just got reelected to a second term in office during the 2012 US Presidential Elections back in November 2012? After all, there are already myriads of external 9-volt (pp3) battery-operated guitar effects already out there that another one could be just as useful as an another hole in one’s head?

The Obama Wah is currently distributed by Big John Music and you can buy one online at www.bigjohnmusic.com. And according to the distributor, this truly unique effect is built point-to-point by hand in Belgium and has a 119 UK pound list price. Basically, it is comprised of two separate guitar effects in one box – a wah-filter and distortion connected in series. And the combo – based on my first-hand listening and playing tests – really worked symbiotically that I really wished the Obama Wah or something like it was available back in 1992 because almost all distortion pedals and wah pedals that I connected in series (at least those that I can afford or fortunate enough to borrow) back then never worked “symbiotically” from an electric guitar musician’s perspective.

The Obama Wah’s distortion section has a volume knob and a gain knob – but the gain section actually works as a voltage controller usable for strange textures in the distortion end of knob twiddling. The wah effect is added to have a sort of an alternate tone control or for filter purposes. For all intents and purposes, the wah section of the Obama Wah is nothing more than a built-in single-band parametric equalizer – just like a good-old wah pedal.

According to the Big John Music advert: “The Big John Obama Wah is for all you guitarists and bassists out there that have been begging for a fixed wah pedal, featuring a voltage-controlled gain distortion and a separate sweepable filter. The Big John Obama Wah brings a whole new ball game to effects pedals.” Probably the most famous recording to have used the Obama Wah is the cocked wah guitar tone of In My Head by Queens of the Stone Age. And the manufacturer also notes that the Obama Wah also works great for analog synths – at least those who already figured out the right tone knob settings since the products introduction.

Even though my Obama Wah sample was a dead-set one that I recently fixed back to life after the previous owner tried to sell it to me for around 10 US dollars, though I finally talked him down to 3, tone-wise, it is truly a must have guitar effects pedal with a “can-do” – and dare I say it “Yes we can!” capability. Even its brand-new retail price seems like a steal in comparison to similarly-priced products already out there. For a product that’s built near the end of the first decade of the 21^st Century, it does have a tone of a product made back when Jimi Hendrix was still alive and despite being made with contemporary bog standard electronic parts of reasonable quality, the Obama Wah seems to have a tone as if it is made with germanium transistors and germanium signal clipping diodes from 1966.

Though one way to improve the Obama Wah further – if you are fortunate enough to buy a pre-owned one whose manufacturer's warranty has already expired and you are confident of your own D.I.Y. electronic tinkering skills is to separate the power supply tap points of the distortion effects section and the wah section of the Obama Wah. Doing this tweak will allow you to use weak 9-volt batteries on the distortion section a la Duane Allman to obtain a pleasing effect on tone, but to keep the Obama Wah's "versatility" across all types of musical styles, the wah - or parametric equalizer section - should be fed fresh and healthy 9-volt batteries. Using one weak 9-volt battery on an unmodified Obama Wah only make it acquire an unduly harsh tone that’s only appropriate for “Death Metal” specific guitarists.  Given it is already quite good as is, I wonder which musicians / bands invited by US President Barack Obama will be using the Obama Wah during the Presidential Inauguration this coming January 21, 2013.   

The 1989 Soldano Super Lead Overdrive: The Best Tube Based Guitar Amplifier Ever?

Now inextricably linked with “guitar gods” Eric Clapton and Mark Knopfler, is the 1989 Soldano SLO the best tube based electric guitar amplifier ever?

By: Ringo Bones

Whenever you Google the 1989 Soldano Super Lead Overdrive (SLO) electric guitar amplifier on the internet – the number one search result is inextricably Dire Straits’ 1985 era Billboard Chart topping classic Money For Nothing, followed by a host of articles pertaining late 1980s era “Hair Metal” tone. Whether you’ve just heard one first hand or have heard one back in 1989 - does the 1989 Soldano Super Lead Overdrive tube-based electric guitar amplifier reign supreme as the best tube based electric guitar amplifier?

When Michael “Mike” Soldano started his Soldano Custom Amplification guitar amplifier manufacturing company in Los Angeles, California back in 1986 – which later relocated to Seattle, Washington - it is mostly known by it’s close-knit cadre of loyal customers for it’ modern, as in push-pull Class AB tube amps based on the circuit design first used by Dr. Jim Marshall back in the 1960s, high-gain electric guitar amplifiers; Particularly their flagship model – the Soldano SLO-100 – which is rated at around 100-watts, and also of their other product lineup of tube-based and solid-state effects units, pedals and electric guitar speaker cabinets. All Soldano electric guitar amplifiers are tube-based and in Class AB configuration that are a high-gain version / improvement of mid-1960s era Jim Marshall circuits.

Mike Soldano originally worked with an electric guitar amp head technician named Bill Sundt in a California shop – Stars Guitars in San Francisco – by modding as in modifying stock Marshall electric guitar head amplifiers to improve their sound or to modify them to create a tone that’s unique or better suited to the owner / guitarist. Which is not surprising given that the first Soldano amp was a result of a modding session of a stock Marshall Plexi and legend has it was used by Dire Straits’ guitarist Mark Knopfler during the recording the session of Money For Nothing of their Brothers In Arms album near the end of 1984.

Mike Soldano and his line of electric guitar amplifiers has earned the reputation amongst the top professional and studio session guitar players – and even amateur guitar playing hobbyists near the end of the 1980s for putting out products that are very high in build quality. Soldano guitar amps had been known to use audiophile-grade components that surpass many of its high-end contemporaries. Eric Clapton and Mark Knopfler “officially” purchased their own Soldano SLOs during a NAMM exhibition back in 1987. Even though Soldano amplifiers are generally priced higher than its competition – i.e. electric guitar amps manufactured by MESA Engineering (MESA / Buggies) or Marshall – Soldano owners / users tend to hold on to and cherish their amplifiers due to their smooth overdrive characteristics. Mike Soldano’s company is also well known for having the best levels of customer support.

Legend has it that the circuit design of Eddie Van Halen’s Peavey 5150 series of amplifiers was “inspired” after Van Halen peeked into his recently purchased Soldano SLO. Though Van Halen’s 5150 (later called the 6505) were based on the plentiful-during-the-Reagan-era (as in 1980s era) 6550 tube and Eddie Van Halen surprisingly made it more “tone-friendly” using his own circuit design. Quite a miraculous design feat indeed because Ronald Reagan era 6550 tubes were not known for their pleasing tonal characteristics – they tend to sound like ordinary sold-state guitar amp designs in the hands of “mediocre” electric guitar amplifier designers. 

In actual use, even though what struck me first was its tonal smoothness even when played at ridiculously loud levels, I was bowled over by the 1989 Soldano SLO’s tonal versatility. In a skilled guitarist, you can forgo your distortion pedals if your fingers are adept enough to allow you to play though a SLO from a smooth legato to a chunky power chord by your right-hand touch and strumming dynamics alone. And if you are a cover-band / tribute band guitarist, you can wow your fans – and your competition – by playing studio version tone accurate renditions of Queensrÿche’s Revolution Calling followed by Lunachicks’ Spoilt just by twiddling the control knobs of the 1989 Soldano SLO amp in 5 seconds or less.      

Remembering Deep Purple’s Jon Lord

Even though he’s a “mere” keyboard player of the pioneering Heavy Metal band Deep Purple, did Jon Lord manage to compose one of the most iconic guitar riffs in heavy metal history?

By: Ringo Bones 

Jon Lord passed away last July 17, 2012 aged 71 marking another sad day in the Heavy Metal Music world. Though he left a legacy that would certainly last as long as the Classical works of Mozart and Beethoven. As every under-40 guitarist today who’s getting formal music education, Deep Purple’s Smoke on the Water is a much-do in any Heavy Metal guitar masterclass. 

Even though he’s a “mere” keyboard player for Deep Purple when the band started in 1968, Jon Lord managed to compose the most iconic Heavy metal guitar riff of all time – i.e. the main riff of Smoke on the Water. Like many iconic musicians of the 1960s, Jon Lord managed to combine the intricate structures of Classical Music and the immediacy of African-American Blues with the visceral impact of Heavy Metal Music. Making Deep Purple stand out against band that merely want to kick-ass by playing as loud as possible without any musical finesse. 

Remembering Dr. Jim Marshall OBE

Dubbed the "Father of Loud" for making rock guitarists be heard in the biggest stadiums, will Dr. Jim Marshall OBE's famed guitar amps continue to evolve without him?

By: Ringo Bones

Maybe its just me, but I always harbored this weird feeling that what Jim Marshall originally wanted was to build a Fender Champ with enough volume that could fill the world's largest arenas and concert stadiums - while keeping the original tone of the 6V6 tube equipped classic. Even though the famed guitar amplifier designer is no longer with us after passing away back in April 5 , 2012 aged 88, Dr. Jim Marshall OBE started one of the greatest "Amp Race" in the electric guitar playing world.

Back in 1962, three extraordinary prototypes were built in Hanwell, England which later became the coveted "Holy Grail" of guitar amplifiers in the electric guitar playing world. The original Marshall amps - the JTM45 Offset Halfstack - used KT66 tubes as the output tubes. Even though latter tube amp versions use 6L6 or the famed Mullard EL34 output tubes, the basic 12AX7 input tube configuration more or less remained the same.

Dr. Jim Marshall's class A triode/pentode switchable amp configuration not only made the amps easier to service while being used in tours and in excruciatingly loud "stadium rock" environments, but also left some room for "improvements" to make it more or less retain the tone of a 6V6 tubed Fender Champ. Famed amp modder Mike Soldano made a name for himself by designing his famed 1989 Soldano Super Lead Overdrive where Marshall left off.

Providing a list of famed musicians and guitarists that made a name for themselves might seem an exercise in yawnarama. But the first ones in the 1960s includes a who's who of the Rock N' Roll Hall of Fame, like Pete Townshend of The Who, Jimi Hendrix, Led Zeppelin, and Black Sabbath. Even until the 1990s, there are still a new generation of gifted musicians making a name for themselves by using Marshall amps to showcase their guitar playing skills like Kurt Cobain of Nirvana and Louise Post and Nina Gordon of Veruca Salt. And even though it is getting harder and harder for a new generation of skilled musicians in today's post NAPSTER music scene, Dr. Jim Marshall's famed guitar amplifier design will probably and surely continue to evolve.