All Valve Dumble in a box possible?

[ER]

Depends on the size of the box...

I would rebuild the II as a poor man's redplate or princeton ultraphonix depending on what you're looking for.

If you just want a "creamy overdrive" pedal I wouldn't worry if it was tube or not.

[drew]

I agree with TM, get a Zendrive for now.

Or build a RF Drive if you're looking for a DIY project.

[renshen1957]

Its probably good advice, I was just hoping that I could build the preamp now and the amp later.

I can get the parts for a ceriatone OTS 50w (which is a lot more then I need for the gigs I am playing at this time) for about $800 inc postage I just don't have the cash and cant see it coming in the near future.

I've emailed London Power asking for a video or sound bites. If there arent any then I think I'll rule it out but if there are then I guess I'll have a tough choice on my hands.

Hi,

London Power does make great circuits in kit form, and Kevin O'Connor (KOC) knows his circuits and electronics, tube and solid state inside out. He has been very helpful and generous with his time (often on subjects not related to powerscaling, his books, or his kits) over at Powerscaling.com and prior to that website on other forums and by emails. London Powers Mini Marshmallow Preamp wouldn't be my first project choice.

KOC's observation on Dumble amps in his 6th volume of the series TUT are informative and educational as to the hows and whys of the circuit. KOC's assessment of H A Dumble was his genius was also in being able to build amps customized to each owners tonal ideal. Unlike a Marshall or Fender, there is no typical Dumble amp.

However, KOC does have some opinions which would not be shared by all Amp Garage members in the Dumble discussion in his books.

KOC does not believe in "voodoo" parts, a metal resistor is a metal resistor and carbon films are noisier so use a metal resistor. Polypropylene Capacitors are better than polyester, don't make a difference. He favors PCBs (which are very well designed) in his kits, which if a pre-amp well have additional parts to decouple nodes in the preamps and galactic grounds not found in an original preamp Dumble Circuit

KOC's books emphasizes proper grounding techniques, proper lead dress, improving existing circuits, achieving the same tonal goal through different methods, etc as the basis of tube amp construction. This design philosophy would extend into the kits.

In his own builds KOC uses Toroid OT and PT, Film Caps to replace Electrolytes, and his amps are housed in rack mounted chassis.

A Dumble Preamp is an ambitious project for the first time constructor.

Now for a few questions?

How many pedal kits have you soldered together and trouble shooted?
How many have built the ground up from a schematic?
Do you have any experience in working around DC voltage above 40 Volts? 115 Volts? 450 Volts?
Do you know the proper precautions to take with a high (well for us builders) DC voltage?
Do you know someone (friend or family member) that was a HAM radio operator who has worked with Tubes who could help you?
Have you ever heard a real Dumble or for that matter a Dumble Clone?

I would suggest some kit building experience under your belt before attempting such an ambitious undertaking.

Personally, my first experience building guitar amp pedals was Craig Anderton's Projects for Guitarists (I don't recommend the book) building from schematics. I found my first tube amp project easier by comparison; I was working from a proven layout diagram. I still had to modify the amp.

If your have your heart set on a Dumble preamp, I would say the Londonpower route would be the route I would choose. How successful your project would be is up to patience, diligence, and frequent checking of your work. I would suggest an alternative

Find a tech or someone with experience to build the London Power kit for you, trouble shoot it, etc. Being able to tweak the values and adjust the pre=amp to achieve the ODS sound requires some experience on the part of the builder.

Good Luck in whatever you decide to do.

Steve

[a_whichello]

At this point I'm thinking of just putting some cash away and getting a ceriatone OTS kit.

I have enough experience building circuits and trouble shooting to build a project like this, its more the modification or combining of schematics that
I don't do so well.

[Structo]

Polypropylene capacitors may be "better" than Polyester on paper and Polyester doesn't have that great of a temperature coefficient but, perhaps that is exactly why Dumble chose polyester because of the tone of the cap when it is heated up by tubes.

He does use Polypropylene in certain cases.

[llemtt]

I agree with TM, get a Zendrive for now.

Or build a RF Drive if you're looking for a DIY project.

there are also zendrive clone kits around...

built one: inexpensive, fantastic! sounds more ODS than an ODS clone built without experience

cheers
Teo