Other Styles

The great thing about building amps is trying all the circuits that you want to audition. If I see an amp design or hear an amp that draws me to it, I can usually find enough data on it to build one- or a reasonable approximation of it.

Take a stroll through some of the varied amps I have that don't fit the major manufacturers or styles in the rest of the site.

One place I have found that really has some interesting designs is on the AX84 forum site. I have build several of their low powered amps that are just perfect for the home user and really sound great. If you are interested in building your own, they are a great resource to draw from.

 

 

Something like a hi gain plexi circuit but using either a single 6V6 or EL84 power tube, this amp is one of my favorites. Great flexibility with two preamp volume controls, treble, middle and bass tonestack and a master volume. I bought a plain pine cabinet and varnished it myself to house this amp. I used a Hammond 16" X 8" X 2" chassis to house the electronics and used Hammond transformers

 

 

 

 

 

Here is the inside look at the back of the cabinet with the rear cover off. It uses 2 12ax7 preamp tubes and has spots for a 6V6 octal power tube or a second socket for an EL84 power tube. You cannot run them both at the same time. This gives this amp a range of 5-8 watts or so. I have a multi output transformers as well as an external bias adjustment pot. This little amp is loud for the small wattage and is just a great practice amp for doing those Led Zepplyn riffs.

 

 

 

 

Just because its small wattage does not mean it is an easy build. This amp has all the circuit complexity of a larger wattage amp and layout and lead dress is important. I studied the schematic and the layouts the website provided and built this custom eyelet board. It has a nice quiet grounding circuit and just nails that plexi sound at a very friendly level.

 

 

 

 

 

I have had an attraction to the amp circuits build by Dr. Z amps for some time. He got his start modifying Hammond Organ amps with the Carmen Ghia amp then developed several other unique circuits. I have adopted and tweaked the Rt.66 circuit for this amp. Its got just a volume, treble and bass control but they work together in a highly unusual manner. When you turn up the bass and treble it also increases the total gain of the amp, much like a volume knob. Then you can use the volume knob more like a Master volume to control the output of the amp. It also uses a huge Hammond output transformer in ultralinear mode and a conjunctive filter between the two power tubes. And the power tubes are KT66 big boys and an EF86 preamp tube and a 12ax7 phase inverter. This amp has a massive clean sound and is a perfect platform for pedals. You can see an extra front panel hole for a Master volume control I tried and took out- not a good match up with this circuit. Its for sale for $600 as a chassis.

 

 

 

 

 

 

 

 

 

 

Here is a shot of the tone controls of this amp. They are the most unique acting I have encountered.

 

 

 

 

Here was a Ghia replica I built in a Hammond Organ donor amp just like the originals. I added a master volume to this one. It had a great overdrive tone and long sustain.

 

 

 

 

I got hold of a dead Blues Jr. amp made by Fender. I had been given a book by Dave Hunter on amps and he had a plan for a modified tweed Princeton circuit that I felt would fit perfectly in this amp format. I sold this amp for $450. It sounded great and was a great platform with a pedal for a nice all around low wattage amp. Nice circuit design. Now Victoria amps is selling a kit of the design for some big bucks.

 

Simple circuit, great tone. Simple controls too. A bright switch, volume and tone. All you need.

 

 

 

 

 

 

 

 

Weber Speakers and Amps have a lot of kits. I didn't need a kit to build this version of their Smokey Joe amp. I think its named after Joe Walsh and his great overdrive tone. Anyways, its an 18 watt cathode biased amp that has some circuit ties back to some of the Supro amps I have seen or built. Uses 2 EL84 tubes and 2 12ax7 preamp tubes. Its about rock tone for sure- volume, tone and master volume.

 

 

Here is a look inside. It uses a large 25 watt power resistor in place of a choke and an interesting circuit design

 

 

 

 

 

 

Here is a reproduction of a Supro Model 24. I have always like the sound of these amps- they are a midrange focused "vintage" sound that amp guys have been raving about for years. I have read with interest all the many theories about the famous "Jimmy Page" amp he used in the studio for those first few Led Zepplin albums and which Supro model it was. I do hear a lot of those first album tones in this circuit. It uses 3 pramp 12ax7 tubes and 2 7989 power tubes (a little crunchier than an EL84 but about the same wattage) and a 5Y3 rectifier.

This amp is built on a turret board and uses great Heyboer custom transformers, so its a lot more robust than the original SUpro (built by Valco) budget amp from the early 60's. I paired this with a 12" Eminence Legend speaker- which is like a Celestion Greenback to my ears- and it does sound good. This amp is for sale for $850.

 

 

 

The control panel shows two channels- I voiced channel one with a little more gain. Channel two has a more midrange focus. The tremolo circuit on this amp is very cool and produces a pronounced throb effect. I built a footpedal for it to switch it on and off but you can also use the speed switch as it also has an on/off feature.

 

 

 

 

 

 

 

No vintage Supro was ever built this nice. A hefty turret board and very short wiring runs make for a nice quiet amp. These amps can have the two input sections connected by a jumper cable to really push the front end more if you want to. Way cool for sure.

You can find very similar circuits on the amps Valco built for Wards, Gretsch, etc. You can save a lot of $ by finding the equivilent amp under the Wards Airline name vs. the Supro name.

 

 

 

 

 

 

Neatness counts. Years from now if an amp tech needs to replace a part it will be so easy compared to the rats nest of a vintage Supro/Valco amp. Secure grounds, logical board layout all mean a long life and easily modified or maintained amps. There are lots of places in a circuit like this to add more gain but then you would not have the Vintage tone you were chasing. This amp cranked with an MKII Tonebender pedal in front of it and you have a whole lot to love.

 

 

 

 

 

My quest for the Supro sound started when I got hold of this Supro twin 10" cabinet. Its the original cabinet from a Model 24 but came with two 10" speakers rather than one 12". I looked for years to find a real chassis to restore and put in this cabinet, but alas, it has never happened.

I did however fit, after much metal work, a Hammond Chassis into the cabinet and I built a full 18 watt JCM800 2204 circuit into this amp. Its got the volume, master, treble, bass and midrange controls just like the 50 watt version. It also has fixed bias and it uses a tube recitfier rather than solid state. I am currently driving a Weber Blue Pup ceramic and a Weber Silver Bell speaker in this amp. I still am not satisfied with those speakers but I will try others as I come across them.

This amp is for sale as well for $650. The cabinet alone is probably worth a lot but I have to keep domestic bliss in the house and my amp room is overflowing into other parts of the house.

 

Its a big circuit but the chassis is long and I was able to make it work out fine. The amp as seen here does not yet have its midrange pot installed but that has been done. This circuit sounds just great driving an 18 watt power section. Great Marshall tone at a very controllable volume. Its quite an impact sitting next to a Supro amp and having a high gain JCM800 sound come out of it.

 

 

 

 

 

 

Here is one of many Sears Silvertone amps I have tuned and restored to vintage sounding glory. Any amp this old will need a few things fixed, especially power capacitors and any badly drifted resistors. I think these amps are a great value for someone looking to start a vintage amp collection with but to be perfectly honest, you need to replace the flabby speaker these were supplied with to really make them sing. There are a few tweaks you can do to the amps for more gain and you can jumper the two sets of inputs together on these for more gain as well.

 

 

 

 

 

This is a Gibson GA20 amp I resurrected from the dead. The amp had a nice old Jensen speaker but it was totally toasted and since the transformer for these amps is mounted on the speaker housing, I also had to replace it as well. This amp was made in 1954 and after I replaced almost all the inside components, it was sounding great! They are more mellow than a Deluxe from the same era but has a unique sound all their own.

 

 

 

 

 

 

Here is a higher wattage 1484 amp from the Silvertone (Danelectro built these) line. Uses two 6L6 tubes that are run at very high voltage to give about 40 watts. These amps have a nice unique tone but they almost without exception need a lot of maintainence to sound their best. These have seen a burst of popularity since Jack Black started playing them- I'll bet he has a top notch amp tech to fix them up too.

I totally redid most of the guts of this basket case and got it sounding good again, just don't expect the reverb to ever sound good.

 

 

 

This was my late 70's Mark IIB Mesa Boogie. I did a number of replacement items in this amp. It uses a good quality PCB board system to mount all the components, so working on them is a total pain. However, after I replaced the power capacitors and some other resistors, she did sing again. And talk about loud. These really need to get loud to sound like the Carlos Santana expectaion of sustain we all expect from these amps, but then I am sure Carlos has his amps custom made for him.

This was a 60 watt version with a massive speaker and it weighed 75 lbs. I finally sold it cause I could not open it up like it needs to be.

 

 

 

 

Here was my first foray into a vintage amp- from the 60's. Its a Gibson Skylark Model GA20T with tremolo. It used two 6AQ5 power tubes for about 12 watts of power and I used to put a distortion pedal in front of it to make it overdrive. It taught me a lot about old amps fixing it up and as a practice amp its just fine. Check them out.

 

 

 

 

 

I do not usually buy new amps as I can make pretty much anything I need. But I did buy this one. Its a Maven Peal RG88 amp. Goes from 1 watt to 88 watts and has both a Tweed Twin channel and a Marshall JCM channel. You can mix and match pairs of power tubes and run each channel on either one pair or all four power tubes. What a beast she is. I live in Vermont and so did the builder, Dave Zimmerman, so I drove down to his shop to pick it up. He is no longer building amps, but I think he's building pedals. He has many great tricks in his amps and a smaller output amp of his- the Zeeta- is used by Warren Hayes on a lot of his and Allman Bros. recordings.

This is the only one in the world in Blue Tolex and is Serial #006 (I picked that number out myself since I got the first one and I wanted to be one better than 007).

It is for sale- not cheap at $2K.