Guitar players will today be raising a glass to Howard Dumble, designer and builder of the amplifier which carried his name for decades whose passing has been announced. You may not have heard of him, but you will have heard the luscious sounds his invention created. Based on a souped up version of 60s Fender amps, he went way beyond a sound which was already pretty darn good. Customers such as Carlos Santana, Lowell George, Eric Johnson, Stevie Ray Vaughan, Robben Ford (whose Fender was the original inspiration for the amp), David Lindley, Jackson Browne, Bonnie Raitt et al would wait months for their amp – there were a few different designs and each one was built by hand to the specific requirements of the player. Mr. D didn’t supply shops – allegedly people applied and he decided who got one. Second hand ones very rarely appear and go for 5 or 6 figures depending on their history. I’ve never even laid eyes on one, but luckily everyone can appreciate the tremendous sound they created.
For the curious, here’s some amp porn presented by the suitably reverent editor of Guitarist mag.
Here’s Robben Ford in Dumble heaven.
As a layman, I find this all rather fascinating but do not really understand many of the arcane details..
However I suspect that on this site, there are more Dunblebores than there are Dumbledores in Hogwarts
More Dumble porn from one of the Feat’s 70s crew:
This is the first Dumble amp, built for Lowell George. Back in 1973 there was a rehearsal complex located in North Hollywood called The Alley. This place was literally built with surplus and recycled materials found in the alleys of North Hollywood. In addition to the two rehearsal spaces there were storage lockers used by many bands including America, Emmy Lou Harris, Jackson Browne, Bonnie Raitt, and Little Feat.
Howard Dumble had a small storage locker of his own there, where he did mods on Fender amps. I remember once as Howard was putting the back on one of the amps with his newly acquired toy, a battery powered screwdriver. He was literally just like a kid in a candy store with the ease of replacing dozens of screws. He even showed me how the torque could drive a screw deep into the wood of the cabinet he was working on.
Here was a laid-back rehearsal complex where Howard was trying to get his amp building business going. Having all these bands in the complex provided Howard with potential clients. A place to hone his expertise. The first Dumble amp, built for Lowell George, came from his space in The Alley. This is the holy grail of Dumble amps. No clue where it is today. A few more Bumble amps were produced in The Alley for Jackson Browne, and Bonnie Raitt. Bonnie’s amp was done in purple suede.
Lowell’s Dumble amp was heavier than a Twin Reverb but worth the extra weight. Lowell always used his black face Princeton Reverb in the studio. The Dumble would be Lowell’s stage rig for some time. On later tours Lowell had a BGW power amp, preamp, and Lexicon reverb, played into a Marshall 4×12 cabinet. This rig was used on the “Who Put the Boot In” festival at the Charlton Football Ground in England. I have a tape from the WB recording truck at this gig and you can hear the smooth sounds this rig created. Not the signature Dumble sound we had become used to hearing.
I used to have a Fuchs that was heavily inspired by a Dumble ODS and I still have an Ethos Overdrive pedal that is essentially a Dumble front end. Both were great at giving that chewy, Dumble midrange.
It’s interesting comparing Dumble with Randall Smith, the founder of Mesa Boogie. Both started by modding Fender amps in the 60s, both progressed to making quite similar cascading gain amps in the 70s, and at the cusp of the 80s both were seen as leaders of the nascent boutique amp industry. These amps had to be custom ordered, had long wait lists and cost several times the price of a Marshall or Fender (US$1500). A Boogie from that era would now cost US$2000. A Dumble is currently for sale for >$300,000.
Mesa went on to be the biggest American amp maker in the world, Dumble remained elusive and ultra-exclusive: there are only a couple of hundred Dumbles, each quite well known.
In terms of the man himself, there is a grainy video from the 80s of him on a TV show explaining the mystical ‘crystal lattice’ that makes his amps unique, and there are some photos of him (a rotund gent who looks like he would be more at home on a tractor than wielding a soldering iron) in a castle-like house from the same era. And then there is a photo taken recently by Don Felder of the Eagles as Dumble is servicing his amp. There are no other known photos or interviews from the 30 years between.
Part of the mystique was maintained by him ‘gooping’ his circuits, covering them in black silicone to make copying difficult. Part was due to his non-starstuck demeanour, making A-list rock stars line up for years or decades before he would make them an amp (When Santana switched to Dumbles in the early 2000, he had to go on tour with a borrowed amp for years before he was ‘allowed’ to own one).
Dumble could have gone the Mesa route and put out a high-end but affordable version of his amp, and he would have made millions. Instead, his is a name relatively unknown even in the guitar world, despite his amps being heard on hundreds of well-known songs.
(Side note: I have no doubt that had Randall Smith taken the Howard Dumble path circa 1980, early Mesa Boogies amps would go for similarly insane amounts now. Dumble ODSs and early Mark series Boogies were very similar in terms of what they were trying to do, with cascading preamp gain, 1X12 speakers and a vocal midrange. It’s no coincidence that many Dumble users also used Mark 1 and Mark 2 Boogies).
I’ve heard the Fuchs are very close. Never heard one. Also the Two Rock are supposedly close – I have a amp sim which emulates a Two Rock which emulates a Dumble which is probably about as close as I’m going to get. But I am very happy with my special edition Blues Junior to be honest, with a few nice pedals in front of it. What does Lowell George know anyway?
I love all this amp arcana. What I don’t completely understand is why it isn’t possible to directly replicate – as in exactly replicate, not just get-pretty-close-to – a Dumble (or any other) custom amplifier.
Is it that the actual physical component parts – some rare tubes perhaps – are simply no longer manufactured and cannot themselves ever be replicated? Or is it that there was something really spooky weird about the way the circuitry was put together that had an entirely random result which cannot be reverse engineered?
Paging @fentonsteve
You can, which is why there are a bunch of Dumble clones (and in fact clones of every desirable amp), BUT there is a lot to do with individual components (resistors and capacitors can vary a bit from stated values) and placement of components within the amp. Things like output transformers, which have a huge impact on sound, may be custom wound and may not be available anymore. Some components now may be better on paper, but sound very different from components manufactured 40 years ago. Then you have the design of the cabinet, the thickness and resonance of the wood etc etc.
Dumble also played into the mythology of his amps, sprouting acoustic and electronic theories that you would have a hard time finding in any textbook.
Btw, if you want to see how ludicrous things get in the guitar world, check out the Klon Centaur pedal which was manufactured in small quantities from the early 90s and now sells for multiple thousands of dollars. You can buy a clone that is indistinguishable for 50 bucks.
HD also coated his circuit boards with epoxy so that they couldn’t easily be documented and replicated. But mainly it’s the combination of components as Pod says, their quality and how the multiple possible combination of values is put together.
One of the main Dumble clones is supposedly the Two Rock, another fine sounding boutique amp. See here – Dumble on the left. Both doing that clean with a bit of hair sound which makes me go brrrr.
A Podicle suggests, the biggest influence on the sound of a valve amp is the audio transformers.
Valves, like transistors, are alike when working in their linear region. But different valves behave differently when overloaded, whereas all transistors just clip and sound like an angry wasp trapped in a jam jar.
And there are as many ways to make a valve amplifer circuit as there are to skin a cat. If Mr Dumble makes you wait years to buy an amp from him and charges over the odds, and he protects his IP by covering the components in epoxy resin, you’re less likely to risk wrecking it by chipping the gunk off. It does make servicing a nightmare, though.
There are also odd things like valves used for DC rectifiers – the classic diode bridge works better on paper, but some people prefer the sound of a valve-rectified rail collapsing under load.
Some wet capacitors do lose their capacitance over time as the electrolyte dries out, which can result in hum or even smoke. That’s why people pay to have old amps ‘re-capped’. Resistors tend to be stable over the longer term, unless they have dissipated too much power and become hot – usually as a result of poor circuit design.
There used to be a little shop tucked away in a side street in Mangotsfield in Bristol, on the way up the hill towards Pucklechurch, that only sold valves. Old valves. New old stock valves. Decent new valves. Pals of mine had their amps resurfaced in there, or whatever it is that you do to a knackered valve amp to bring it back to life. I had a litle Fender Vibrochamp that didn’t ever let me down, and a Laney Linebacker (which I still have) and I never needed to use his facilties for replacement valveage. How I wish I’d had a clue as to which valves were going to become rare and sought-after; I’d have invested heavily. The little shop, inevitably, has now passed on, along with its owner, to the great hum in the sky.
I think a valve is a thing of beauty. Design and aesthetically
‘…mid scope with a very extended bottom end…’ That’s not something you hear every day. The amp sounds gorgeous though.
Another of Lowell’s…
Do you think he’d bought a job lot of ‘Medeval’ font Letraset?
What makes you think he had a medieval fetish?
https://celebsaga.com/wp-content/uploads/2022/01/d418d5e903f56ed2325d592fcd0f10.jpg
I glanced at the thread title and thought ‘Someone has written a spoof obituary of an imaginary person’.
That’s because John McLaughlin couldn’t get one.
It sounds like Charles Dickens was his first customer!
I got curious to see a photo of Mr D.
Here’s some more Dumbleporn. Sensitive readers be warned.!This is pretty hardcore stuff.
“Even my open-back enclosures use air to the optimum.”
And an interview with the great man from 1955.
https://thesubjectmatter.com/dumblearchive/Articles/default.htm
Can I just say, all this talk of “cascading gain stages” and “epoxy resin potting” has caused two palm-sized holes in my trousers where I’ve been rubbing my thighs too hard?
Phwoar!
Post-preamp drive. Nurse!