Frank's Tubeworks...
K4AVL (Eastern USA)

Custom vacuum tube-based products and services for musicians,
hi-fi enthusiasts, and old radio buffs, spanning the old and new...

Newly available (Spring, 2014)
Custom Univox Super Fuzz clone - the "Anubi-Fuzz Classic"
Click on the image for more information:


Newly available (Spring, 2007)
1958 Fender Tweed Bassman 5F6A clones built to order
in "head cabinet" (no speakers), also available as chassis-only version.
Click on the image to go to the guitar amp page:


Scroll down for available hi-fi items / pictures...

Contrary to popular belief, vacuum-tube circuits are still "state-of-the-art", and preferred by the majority of serious musicians and audiophiles. There are still new designs being formulated by both old and young in the technical forums, and well as reproductions and enhancements to old designs. The demand for many of the "core" amp components is so large that most of the components as well as tubes are still being manufactured today, and most new-design amps as well as aging classics command a premium price.


Let me do your next refurbishing/restoration work, or build you a new unit from scratch with new parts.
I can also locate items for you on Ebay, then inspect, rebuild and restore them to usable condition...

Also providing parts location service (including procurement from multiple sources if neccessary) to ship you a set of items you need at the most reasonable prices I can find, if you don't have the time to do the legwork.

To summarize, I offer the following services:
  • New tube guitar amps built to original vintage schematics (Fender, etc.)
    (functional chassis with tubes only, no enclosure or speakers)
  • Any model/brand can be reproduced depending on schematic availability
  • If you need a specific chassis size to fit an old amp unit, rather than a random size, I need to know at the outset, as these may often need to be specially ordered and command a higher price
  • New hi-fi tube amps built to vintage design specs, or modified newer designs
    (as above, chassis only, however if you have specific enclosure designs in mind, and have done the legwork on the materials/sources, I'd be willing to fabricate these as well).
  • As far as "looks & cosmetics", I can do new projects using more innovative materials, such as a brass anodized aluminum chassis top mounted on an oak frame, sheet metal transformer enclosures so that all you see are the tubes on top, and also units with varying amounts of plexiglass (Lexan), for the "see through" look, and perhaps extra pilot lights to bathe the whole unit in a blue, green, or red glow when turned on.
  • Currently featured items I offer (with almost 100% brand-new parts, recent or "enhanced classic" design, and hand built by myself when each order is placed): a 2 tube preamp, a 3.5 watt miniblock, and a 6-tube 12 watt hi-fi push-pull amp (using NOS 6V6GT or new 6V6S Slovak tubes as the finals). See the picture section below for more info. Write me for more detailed specs.
  • Pre-emptive or remedial upgrading: Any old tube unit, especially pre-1970, may have some components that may have failed or are ready to fail (especially capacitors) which could cause performance loss or permanently damage your unit. I can replace these, as well as look for other problems (component drift, etc.), and do some basic cleaning, check for bad contacts, etc.
  • General tube radio repairs (they were usually AM-only in those days), replacing all components that may have failed or are expected to fail, reducing/eliminating hum, poor or dangerous grounding, power cords, etc.
    If there is any major damage or burnout to certain parts, I may need to use old or vintage parts to replace them, as quite often with old tube radios, the same parts are no longer available. If I need to re-drill or do something which will cosmetically alter your radio in an obvious way, I will contact you first for permission. When I replace capacitors, I leave the cans in place, just bypass them with newer parts under the chassis.
  • Work also done on portable tube-based phonographs and other items.
  • Very "modest" on-the-road type (slightly crude) one-element speaker enclosures (with speaker, jack/terminals. and carrying handle, cloth front, spray painted black), made with the speaker of your choice using particle board with a masonite back. These are available for musicians at a reasonable price, custom built. Not for living room use.
  • Feel free to inquire about any other needs you may have, no job too small.
  • One caveat: I don't currently accept any jobs for work on old television sets.

My prices are very reasonable, if the parts to build a brand-new component from scratch cost me $200, I will only charge $200 more for labor, legwork on finding the parts, all work and testing, packaging & handling, etc. The only additional expense to you is the final shipping of the unit. I will need a full deposit of the cost of materials before beginning work (including my shipping costs to procure the parts). For general repairs/refurbishing, I will generally only charge $50-$100 plus parts & shipping, depending on the complexity of the work. If I cannot solve your problem in a reasonable amount of time, there will be no charge for labor, just a $25 handling charge, cost of new parts which I did replace, and return shipping.

Featured items (all are chassis-only, no cabinet):


This simple preamp is available for $150, mono, fully self-contained and low distortion. A preamp is needed if you do not have enough gain to drive your final amp, for example from a turntable. You most likely will not need one of these for connecting a tuner, CD or tape player to a tube amp (for example the one I offer below). You may wire two of these in series for more gain. A two-channel (stereo) version on a single chassis is available for just $100 more. Add $25 (per channel) for a version on a slighly larger chassis with added bass/treble controls.


Underside of the pre-amp

bax2 bax1

A simple Baxandall "tone stack". If you don't have any tone controls on your pre-amp or final amp, add this between the two, using a short RCA cable. Available for $25 mono, $50 stereo.

12 Watt Mono all-tube Hi-Fi amp built to order:


This is currently my "signature" hi-fi item, a very nice looking 12 watt all-tube mono hi-fi amp, available for $485. Connect your tuner, CD or tape deck directly into this and to your speakers. You may use 1 speaker from the 8 ohm terminals, or two in parallel from the 4 ohm terminals, etc. This is built with all-new parts. In the picture, I'm using a new Ruby 5U4GC rectifier tube, and two JJ 6V6S output tubes rather than American NOS tubes, they do look good and perform well. Has a volume control but no tone controls (see above), and needs a pre-amp (above) only for a turntable.


The underside of the 12 watt hi-fi amp.


This miniblock is a mono 3.5 watt push-pull amp using two 13EM7 tubes and a solid-state rectifier circuit. It's not powerful, but can play a tiny transistor radio/walkman/ipod (from their headphone jacks) loudly into a big speaker, works great as an amp for your computer output into a big speaker, but needs a pre-amp for a turntable. I will build future copies with a standard chassis. It was a huge undertaking to use this blue case, I needed to fabricate a circuit board and slide it in, as it only opened up on the ends. I am offering it for $240 on a plain chassis.

Remember that most vintage hi-fi components are "mono", not stereo, but can be run to 2 speakers in series or parallel depending on the specs of the speakers, and perhaps a jumper change on the amp in most cases. If you need a "stereo" version of the amp, it will require twice the amount of tubes (generally), but the cost will be somewhat less than double, due to being able to use some portions of the power supply for both channels, as well as just one (but larger) chassis.
I'm also planning to build a prototype of nicely designed 30 watt amp, using some classic 7-pin military tubes from WW-II, these tubes can be driven a lot higher, but this design is new and extremely fine-tuned, with both solid-state and tube regulators. It will probably be in the $600 range but look nice with the ceramic plate caps, big tubes, etc. Ten tubes for one channel. Check back for upcoming details, possibly April...
Basically, I can put together any circuit for which I have the schematic and parts specs, test and ship it. Mention your parts preferences when ordering. The turnaround time is generally 3 weeks on an order, unless something gets back-ordered from one of my suppliers. If I build a certain design which you provide, I cannot be held responsible for flaws in the design performance, aside from being true to your specifications.
By the way, output power is logarithmic, not linear, a 30 watt amp will not even be 50% louder than a 10 watt amp. Solid state technology has inherent distortion issues, still unresolved, and you'd need a lot of watts to even begin to compare the sound to even a modest tube amp.

Photo Gallery of other work and miscellaneous:


Some of the (mostly) modern parts still made today for tube circuits


A 1948 Radio Craftsmen five tube mono 12 watt Hi-Fi amp which I restored. It's similar in specs to the 12 watt amp I offer (above), but a different design. It, too, uses a pair of 6V6GT tubes for the output stage.


The underside of the above, I completely re-did the wiring and components to restore it to the original 1948 design, after someone about 30 years ago had severely mangled it and tried to "re-invent" it a different way.


A 1938 Westinghouse 2-band radio which I restored.


The top of the above Westinghouse chassis, this is a real classic...


An old (circa 1940) Emerson 78 rpm phono / AM radio which I restored

Economy "road" speakers which I can custom make for musicians

Click here to send an e-mail inquiry.

Phone contact: Frank F. at (570)-814-9566 (my cell phone)

Thanks for stopping by to visit this site, and please pass it on...


Recommended site .....ANUBIS SPIRE..... - - click on the image below: