A Dumble Book

You know how it is.  You've always wanted to plug in to a Dumble amplifier. 

But with fewer than 300 in known existence, a chance encounter with one of these beasts will be about as rare as a sighting of the Loch Ness monster.  Collectors and players fortunate enough to own a Dumble are certainly keeping them locked up, away from prying eyes and itchy fingers. 

Alexander Dumble has always been choosy about who he builds amplifiers for.  And now that it seems that he is building amplifiers only when he feels like it and for a very select few, it appears that the few Dumbles that do appear on the re-sale market are packing double their already five-figure prices from, say, 5 years ago.

So, like giving a Nigella cookbook to a starving man, we have A Dumble Book by Jesse Schwarz. 

In its 332 pages are three interviews with Alexander Dumble, an extensive amp history with specs and descriptions of nearly every model, amplifier tests, and an interview with Dumble's long time friend and business partner Jack Smith.   All 90 photographs in the book are in full color.

It is interesting to note that while Jesse Schwarz is credited with coordinating and doing most of the writing for this project, other Dumble amplifier owners have also come forward to contribute in this homage to Alexander Dumble.

Deserving of specific mention in A Dumble Book are Steve Lukather's Overdrive Special serial #048 and David Lindley's Steel String Singer #003. 

And here's a brief history of Dumble amplifiers.

http://www.dumblebook.com/

1979 Dumble Overdrive Deluxe Demo!

Here's one for all the Dumble freaks, umm.. afficionados out there!   The basic Dumble amplifier design is based around the Fender Deluxe circuit but modified to achieve much higher gain, more harmonic complexity at the top-end and more low-end on the bass.



Dumbles are hand-built from the ground up but this video features what is said to be a Dumble-modified Fender Deluxe amp -- a real rarity.  Alexander Dumble retained the tremelo and reverb circuit on this amp, and it also sounds like he goosed up the intensity of the tremelo a fair bit -- warm, lush, pulsating and downright hypnotic!

And dig the '2001: Space Odyssey'-style amp face lettering -- another Dumble hallmark.

Head over to this YouTube link for more:
http://www.youtube.com/watch?v=9U1mrbqyEyw&feature=related

You can also check out my earlier article on Dumble amps with a great video demo of the Overdrive Special by guitarist Gregor Hilden here:
http://www.theguitarcolumn.com/2009/07/boutique-amp-maker-alexander-dumble.html

Stevie Ray Vaughan's Studio Tone Secrets

Stevie Ray virtually redefined the sound of blues guitar. His fanatical attention to tone and the measures he took to get it are legendary.

The pic at right was taken during the In Step recording sessions by SRV's amp tech, the late, great Cesar Diaz -- the 'Amp Doctor'.


Stevie's amp setup from left to right were:

• A Marshall JCM800 driving a Marshall 4x12 slant cab
• A blonde '62 Fender Twin Reverb
• A 150-watt Dumble Steel String Singer head on a Dumble 4x12 cabinet
• Two '64 blackface Fender Vibroverbs (that happened to have consecutive serial numbers), each equipped with a 15" speaker
• Two KT88-equipped Marshall Major 200-watt heads driving Marshall 4x15 and 8x10 cabinets

The speaker tally for this setup is interesting -- an 8x10 cab, two 4x12 cabs, a single 12" in the Twin, a 4x15 cab and two 15" speakers in the Vibroverbs. With eight 10", nine 12" and six 15" speakers, Stevie Ray could cover the entire sonic spectrum. His fondness for 15" speakers no doubt contributed greatly to his full-bodied, beefy tone.

For the In Step sessions, Stevie also relied on his ever-present Ibanez TS808 Tubescreamer, a Vox wah, a FuzzFace and an Octavia which he used in tandem with the Tubescreamer.

The Tubescreamer took a toll on his amplifiers which were already turned up to the point of breakup -- he would set it up so that it hit his amps hard with a hot, clean boost. According to Stevie, coupled with his heavy technique, and .013-.058 strings tuned to Eb, "I give my amps between two weeks to a month, and then they sound horrible."

Gear aside, the real secret to SRV's tone was in his hands. He could have plugged into a Fender Champ and still revolutionized the blues.

Steve Lukather's Paul Rivera Modified Fender Princeton

Here's an eBay listing for Steve Lukather's Fender Princeton Reverb amp:

http://cgi.ebay.com/Steve-Lukather-Fender-Princeton-Reverb-Amplifier_W0QQitemZ200380004115QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item2ea7943713&_trksid=p3911.c0.m14

(The link will go down once the amp is sold)


Leo Fender had it right the first time.

The circuits for the Fender Princeton, Deluxe and Twin Reverb have long been the templates on which other American amplifier manufacturers have been building on.

And Fender's circuitry was adaptable and relatively easy to modify.

For instance, before launching his Boogie amplifiers, Randall Smith got his start by modifying Fender Princeton's in his garage, introducing cascading gain stages that enabled the little amp to scream with almost infinite sustain even at low, hotel room volumes.

Across the pond, Jim Marshall was basing his earliest creations on the original tweed Fender Bassman amps, but powered with EL34 power tubes instead of the American 6L6's.

Even Alexander Dumble designed his amplifiers around the Fender Deluxe schematic. And as Lowell George once put it, “A Dumble is a Fender made right.”

And more amp hot-rodders rose to the task to meet the needs of a tone and gain hungry clientele with each building a reputation based on their work modding the amplifiers of rock’s elite -- Jose Arredondo (Eddie Van Halen, Steve Vai), Harry Kolbe (Al DiMeola, Allan Holdsworth, Yngwie Malmsteen) and Paul Rivera (Steve Lukather, Larry Carlton and many of LA’s session elite). Rivera was also a pioneer in building custom pedalboards and effects racks for studio guitarists in the late 70's.

Which brings us to Mr. Lukather's Rivera-modded Princeton. As the eBay listing describes it, this Princeton was Lukather's 'go to' amp from 1976 to 1982 and has appeared on a lot of his session work.

And it's not surprising. With its low wattage -- two 6V6 power tubes producing all of 12 watts -- the Fender Princeton was the secret weapon of many studio guitar players. The amp could be cranked if needed without becoming overbearing and, with a possible modification or two, could produce a gamut of tones from silky clean to high-gain.

Rivera's mods to Lukather's amp in this case included a 6-position rotary switch in place of the second input jack which enabled a selection of six different mid-boost frequencies. The red knob that was installed in place of the vibrato speed knob is a control for adding gain to any one of those six mid-frequencies.

As he did to most of the amps he worked on, Rivera also probably reworked the amp with his Stage 2 Plus mod where the preamp, output stage and power supply are modified to produce a smoother, more articulate distortion.

Paul Rivera went on to manufacture his own line of Rivera amplifiers in the late '80s. Lukather, ever the loyal customer, started endorsing his own signature model Rivera Bonehead amps in 1999.

A Visit To Ceriatone Amplifiers Part II

The following interview with Ceriatone's Nik Azam is excerpted from my hour-and-a-half long visit:




The Guitar Column: I see you use a lot of orange capacitors on your circuit boards. Some have been labelled 'Holy Grail'. Care to share with us what that's about, or is it a trade secret?
Nik Azam: They're no secret -- the orange capacitors are made by Sprague. They are the only ones that will give the proper sound. The Holy Grail electrolytic caps are made locally in Penang (to Ceriatone's specs). It's an availability issue for these if we have to order it everytime from the US.

TGC: I see from your website that you also offer your amps in kit form. Of course putting an amp together from scratch is no simple matter.

NA: Yes, a certain amount of (electrical) knowledge is presumed on the part of the builder. It's an experience for the beginner who wants to learn to put together their first amp.




TGC: Then there is the issue of tube biasing. From what I know it can be dangerous if you're not sure of what you're doing.

NA: Biasing is easy once you know how to do it. And if the customer needs it, I will give them step by step instructions so they can (safely) do it themselves. And it's really not that difficult.

TGC: Do you think there is a difference in tone between amps with printed circuit boards (PCBs), and handwired amplifiers with point-to-point wiring?

NA: No there shouldn't be any difference. But the reason the big manufacturers use PCBs is that they are trying to squeeze in as many features as they can. This means that they have to substitute parts with smaller (alternative) components and that can affect the sound.

(Of the boutique amps) Fuchs uses PCBs -- they go for around US$3,000; Two-Rock amps are hand-wired, they're about US$8,000. People see our Overtone Special, which is modelled on the Dumble for US$1,000 and they go 'why not?' The Dumble amp is US$40,000.





TGC: How did you happen to come across the Dumble circuit? Dumble would put black epoxy over his circuit to conceal the parts.

NA: A couple of Dumbles were actually 'de-gooped' a few years ago, probably using some chemical agents to remove the epoxy. The parts were revealed and their values measured. After that it became public knowledge on the amp forums in the States.

TGC: What is the Overtone S&M Special?

NA: It's based on our Overtone Special. There are some mods in there that were created for two very early customers of mine, friends really -- Sami and Marin. Of course there's the double entendre of 'S&M'..

TGC: What is your view on transformer ratings? There is the opinion that it is better to use a 110v transformer like they use in the US, and then use an external step-up transformer if you're in a country where the mains are not 110v. I had this experience with Matchless amps myself. I thought Matchless didn't sound very good at all, rather dull and lifeless --the ones with the 220v transformer. Then I tried the 110v Matchless amps in the States and they were amazing. What's your view on this?

NA: Technically there should be no difference -- you're just using different leads on the transformer to adjust for the different voltage coming in to the amp -- 110, 120, 220 and 240v.

The change in sound in those Matchless amps may be because of some minor damage during shipping -- things can get moved around inside during shipping, altering the tone.






TGC: What do you think of the opinion that birch ply is the best wood to use for amp cabinets? Some people swear that birch plywood is the only way to go for the tone.

NA: Marshall started using birch ply simply because it was available and it wasn't expensive. Wood availability is a function of geography. In Malaysia of course, birch is not available. We use marine-grade ply made of local hardwoods.

TGC: I notice on your shelf over there that you have several face-plates marked with the word 'reject' on them. To be honest, I can't spot anything wrong with them -- your quality control standards must be very high.

NA: All our face-plates use the traditional silk-screen method for the lettering. Sometimes there is a little smear or imperfection somewhere (on the lettering) so we reject it. Because we're in Asia and we sell amps around the world, sometimes a small imperfection can get amplified. And nowadays with the internet, word spreads quickly.

We went through seven different vendors before we settled on one who could make our face-plates with a low rejection rate.

TGC: What about the grille cloth on your amps? They look good -- are those from a local supplier?

NA: I get them from China. I have to purchase a minimum of 10,000 meters of fabric before they will sell them to me. The best time to purchase parts from China is at the end of the year when vendors are trying to sell off their stock for the year.

TGC: Do you make your amp cabinets in-house?

NA: I get the cabinets made (by a vendor) -- a two-man operation makes them. No CNC machines. They build the cabinets by hand using marine ply and regular dowel joints and then cover the cabinets with black Tolex. We do get requests for other colors but I try to keep it simple -- it's available in any color as long as it's black!

We have only four basic cabinet types for our amp heads -- we try to streamline operations.

TGC: What speakers options do you offer? And what about speaker ohms -- does that affect the sound?

NA: We use Celestion speakers mainly, or Jensens. Based on the output of the transformers, 16 ohms will give the fullest sound. But it also depends on the number of speakers you're using, the type of speaker, whether they're wired in series..

TGC: Which is your most popular amp model?

NA: It depends on the flavor of the month. One month it may be the JTM45, another the TrainWreck clone. But for the last couple of years the Overtone Special has been hands-down the most popular.

TGC: I have to ask -- of your entire line, which amp are you most proud of?

NA: I'm proud of all of them.

TGC: To be more specific, given your entire amp range, which one would you choose to take to a gig?

NA: I would take the JTM45.

A Visit To Ceriatone Amplifiers Part I

I had the opportunity to visit the Ceriatone amplifier shop on Thursday 3rd September.

Ceriatone, in case you haven't heard, is a boutique line of hand-wired amplifiers that is fast catching on internationally. Although the company produces a variety amp models, Ceriatone is most famous for their Overtone Special which is modelled on the Dumble Overdrive Special, the Holy Grail of guitar amplifiers.

They are also the most reasonably priced of any boutique amp -- although that may all change very soon, if guitar gear industry trends are anything to go by. But I doubt if they will be anywhere in the ballpark of what an authentic Dumble goes for these days.

Ceriatone is located on the second floor of an inconspicuos shop-house in downtown Kuala Lumpur, Malaysia. As we made our way up the flight of stairs I was half-expecting to find Ceriatone's intrepid founder, Nik Azam, hunkered over a workbench strewn with assorted amp parts and miles of copper wire.

I couldn't have been more wrong.

In two rows, on opposite sides of the shop floor, eight technicians were hard at work soldering point-to-point wiring on several Ceriatone amp models. Each tech worked on one amp chassis at a time, assembling every component for that particular amp. This was a cottage industry at its finest.

The floor to ceiling wall shelves, well stocked with amp face plates, tubes, transformers and miscellaneous parts, were testimony to the considerable output of amplifiers Ceriatone was producing to meet market demand.

Nik Azam was the perfect host, graciously taking the time to show us around, patiently answering every question while sharing with us his vast knowledge of amplifier history and design.

In Part II, I will feature an interview with Ceriatone's Nik Azam.

Ceriatone Overtone Special | Dumble In Disguise?

I was turned on to Ceriatone amps a couple of days ago by a musician friend. He's from the older school 'Fender is king' generation and he was hipping me to this amp builder in Malaysia who made brilliant Fender copies. And at less than two-thirds the price.

A quick Google search revealed this: http://www.ceriatone.com/

Interesting. A Malaysian amp builder going toe-to-toe with Marshall and Fender, not to mention the big boys of boutique American amps -- Fuchs, Trainwreck, Matchless. And yes... even Mr Dumble.
Granted, Ceriatone is still at the 'copy' stage. But remember Peavey's Fender tweed-style design on their Classic series amps (complete with chickenhead knobs) of a few years ago? Peavey resurrected tweed when Fender had put it to bed. It was good marketing and a good way to get noticed.

Check out the Dumble-like font on the Ceriatone Overtone Special at right -- it sort of reads like 'Overdrive Special' from five feet away. Surely to be a nifty conversation piece for the owner.

But fortunately the similarities are not merely cosmetic. Ceriatone has also added new, useful features to the original amp design, giving the user more tonal options and flexibility.

And listening to Jack Zucker's clip above, it sounds great.

Based on Zucker's description, the front panel controls from left to right are:

FET input jack
Normal input jack
Input control
Bright switch
Deep switch
Jazz/Rock switch
Treble
Mid
Bass
Level control for overdrive
Ratio control for the overdrive, for controlling relative volumes for lead and rhythm sounds
Master volume control
Presence control


On the back panel:

Mid-Boost switch that defeats the tone controls (for manual switching)
Lead and Rhythm switch (for manual switching)
Footswitch jack for controlling Rhythm/Lead and Mid-Boost controls
Passive effects loop

I'm real curious to try one of these out for myself.

Boutique Amp Maker Alexander Dumble

Alexander Dumble (formerly Howard Dumble until he legally changed his name) makes the most sought after boutique amplifiers in the world. Every amplifier is personally hand-built to order and the waiting list can take several years. And Dumble does not build them for just anyone -- his criteria for accepting a customer’s order remains as much of a mystery as the 'secret' components which he conceals with black epoxy on his circuit boards.


With his ‘one amplifier per customer’ policy, the sheer scarcity of Dumble amplifiers in existence only adds to the overall mystique. A pre-owned Dumble, if you can find one on the market, goes for several times its original price, well above five figures.

Dumble started modifying and building amplifiers out of his backyard workshop, all the while making a living as a touring guitarist and studio musician.

In 1965, as an 18-year old, he was commissioned by Semie Moseley to build 10 Mosrite amplifiers for The Ventures who were among the very first guitar endorsees with their own signature model equipment. The Ventures did not cotton to his amps which they felt were ‘a little too rock n’ roll’ for their kind of music but they offered young Howard a business proposition nonetheless. Dumble declined and went back to playing guitar to pay his bills.

In 1969 he built his Explosion model amp which was later improved and re-voiced to become the Overdrive Special. Ironically, the basic Dumble design is based around the Fender Deluxe circuit but modified to achieve much higher gain, more harmonic complexity at the top-end and more low-end on the bass.

Other models in the Dumble range include the Steel String Singer, the Dumbleland, 25-watt Hotel Hog, 50-watt Dumbleman, a 450-watt bass amp dubbed the Winterland, the modular rack-mounted Phoenix and the Dumbleator – the latter being a device to interface his amplifiers with effects, much like an effects loop.

Over the last 10 years or so, several Dumble amplifier owners have allowed their amplifiers to be 'de-gooped' of the black epoxy Dumble used to conceal his component values, and copies of his circuit design have floated around the internet. As a result some amplifier companies have emerged with their own Dumble clones. Some have even taken it further with their own variations on the design. But many who have played through a real Dumble amplifier testify that certain tonal ingredients were missing from these clones.

The clip above shows guitarist Gregor Hilden wrangling some pretty sweet tones from an Overdrive Special -- one of the best examples actually, that I've heard of this amp in action.

If you happen to come across a Dumble amp, ask if you can plug in and try it out. You'll never know when, or if, you'll ever see another one. And you owe it to yourself to experience what all the hype is about. I'm still waiting on that opportunity myself.

Eric Johnson's Cliffs of Dover | Techniques and Equipment

Here's a clip of maestro Eric Johnson doing his thing on Cliffs of Dover. In the world of instrumental rock guitar, it's rare that a piece stands the test of time while being the signature tune most closely associated with the artist. Eric's Cliffs of Dover is just one such rarity.

On this clip he plays a lengthy intro with his most pristine of chimey clean tones, courtesy of the 4th position of the pickup selector switch on his Stratocaster. His clean sound is pumped through two Fender Twin Reverbs amps, each driving two 12" speakers in a single Marshall 4x12 cabinet for stereo. This cabinet is an open back, which allows him to get the bottom-end of a Marshall cab while still maintaining the open-back characteristics of a Fender Twin.

His clean tone is awash with copious amounts of Electro Harmonix Memory Man and/or Echoplex tape delay and a hint of chorus from his TC Electronics Chorus unit which he also uses as a splitter to send his signal to his two Twin Reverbs.

The background 'loop' sounds like an a 800ms sample from a Boss DD-2 Digital Delay pedal. Back in the day, the Boss DD's were among the few that provided a short sampling feature so that loops could be created on the fly. But you were limited to only 800ms of sampling time.

At 1:41-1:51, Eric uses what he calls his ' japanese koto' technique. While fretting notes conventionally with his left hand, he employs a thumb and forefinger technique with his right hand -- he plucks the note with his thumb while the index finger lightly dampens a note on the same string right next to the fret played with the left hand. He then adds a little vibrato with the left hand.

At 3:01 he flips to the lead pickup on his Strat, switches to his lead channel and begins traversing the fingerboard with his trademark pentatonic flurries. Unlike most players who approach pentatonics with hammer-ons and pull-offs, Eric prefers to alternate pick most of his pentatonic ideas. He describes his slightly unconventional picking technique as alternate picking where he holds the pick at an angle to minimize friction and faciltitate speed. He also picks from the guitar's body up into the air, brushing the string with the side of the pick with a slight bounce in the wrist. He's been known to lightly sandpaper the sides of his red Jazz III picks to create a finely rough surface to facilitate this brushing effect.

On his lead channel is a TC Electronic's Sustainer, a Fender Reverb unit, another Echoplex and a Chandler Tube Driver.

Interestingly, Eric places the Tube Driver after his reverb and delays. This gives his tone a characteristic warmth with a bit of 'mud' as his effected signal is being pumped into his overdrive.

His amp setup for his lead channel is either a Marshall 100 watt head, or the holy grail of amps, the Dumble Overdrive Special. His speaker cabinet of choice for this channel is a closed-back Marshall 4x12.

At 3:31 Eric makes a quick tonal adjustment on the lower tone knob. Strats are conventionally wired such that the first tone knob controls the front pickup and the second lower tone knob controls the middle pickup. The lead pickup is not wired to a tone control. Since Eric is on the 5th position on his pickup selector, this shows that his lead pickup is wired to his second tone control. Joe Bonamassa also talks about this very useful and simple Strat mod, which I mention here. This helps take off some of the shrill top-end when using the Strat's lead pickup on its own.

Eric Johnson is one of those rare masters of touch, tone and technique and all three elements feature abundantly in both his live performances and in his studio recordings. But his near-fanatical attention to detail on his solo records means that he probably spends more time than he should on each one -- which makes his recorded output pretty scarce.


Check Out Eric Johnson CDs And DVDs Here!