Tode Guitar Amplifier Kit
Inspiration for Tode came from looking at an obscure yet classic design, the Mullard 3-3 hi fi amp. This neat little amp was simple yet quite unconventional, and it had the right basic stuff – EF86 input tube, the marvelous EL84 output tube, and very few other parts to muck up the sound. Now it wasn’t a cake walk, there would need to be some creative thinking to get a similar circuit to work with a guitar. The direct coupled design that makes the Tode so responsive meant that we needed creative ways to control gain and master volume.
But hey, unconventional and clever solutions are what Bottlehead does best! So we cooked up a variable feedback circuit to control gain, that lets you go from squeaky clean to a nice gnarly crunch. And we put a variable brake on the amp. The brake lets you play clean or distorted, as loud or as soft as you like. It works with the internal 8″ Weber speaker, or with an external cabinet. Tode will play pretty darned loud with a 4×12 cabinet, we measured 112dB at 1 meter from a 4×12 with four Celestion G12T-75s when shooting the Kevin Crew video. Good thing our neighbors weren’t around! And you can even crunch to your heart’s content on your favorite headphones. Heck, you could even run a crunchy line out into a console!
What about tone control? Well for starters, this is no mud box. If you plug different guitars into this amp, they are gonna sound different. Unless you have some obscure axe you already have volume and treble controls on it, so we didn’t see the need for redundant controls on the amp. But a really cool tone curve that a lot of players like is a midrange scoop. So how about two of ’em? We give you a choice of flat (actually ever so slightly present in the midrange, just a dB or two) a setting for a 15dB scoop centered round 1000Hz that emulates the scoop sound that you get when you turn the mid down and the treble and bass up on a famous amp that starts with M, and a setting for a 15dB scoop around 500 Hz that emulates a scoop more like an amp that starts with F.
How the controls work
MID SCOOP
This is a three position rotary switch. It controls a notch filter that is at the input of the amp.
FLAT setting gives you a flat response with the FEEDBACK control all the way to CREAMY and a very slight midrange presence with the FEEDBACK control all the way to CRUNCHY
EMish switches in about a 15dB notch at about 1000Hz, similar to what you measure when you turn the treble and bass all the way up and the midrange all the way down on a M******* amp.
EFish switches in about a 15dB notch at about 500Hz, similar to what you measure when you turn the treble, midrange and bass all the way up on a F***** amp.
FEEDBACK
This potentiometer controls the amount of global negative feedback in the amp circuit.
As the knob is turned toward CREAMY the feedback in increased, up to about 20dB. The amp gain drops and the amp plays clean.
As the knob is turned toward CRUNCHY, the feedback is progressively removed. The amp gain goes up and the amp becomes easier to drive into distortion.
BRAKE
This variable L-pad controls the amount of signal that is allowed into the speaker. It functions the same whether you use the internal Weber speaker, an external cabinet, or headphones.
As the knob is turned toward FULL STOP the output level decreases.
As the knob is turned toward FULL SPEED the output level increases.
Amp distortion will not change when adjusting this control, so you can crank up your volume knob on your guitar and turn the feedback toward CRUNCHY to get maximum distortion, then turn the brake down to keep the distortion quality the same at low output levels. Inducing speaker distortion on top of amp distortion will of course require turning the brake toward FULL SPEED to drive the speaker hard enough to distort.
Using headphones
The trick with headphones is to turn the brake almost all the way to FULL STOP. Start playing and turn the BRAKE to a level that that is comfortable (go easy, please don’t damage your hearing!). Then adjust the MID SCOOP control for the tone you want and the FEEDBACK control to get the amount of distortion you want, and fine tune the BRAKE again for a comfortable listening level. Plugging headphones in will automatically cut the signal to the internal 8” speaker or an external cabinet.
Specifications
• Circuit topology: Direct coupled all pentode single ended with variable global negative feedback
• Power output: Clean to 3 Watts RMS into 4 ohms, fully distorted about 10 Watts RMS into 4 ohms
• Input impedance: 10 Megohms
• Sensitivity: About 100mV for 3W output with feedback knob at maximum cream (clean) setting (20dB of global negative feedback)
• Frequency response: Full feedback 50Hz-20kHz
Zero feedback 110Hz–20kHz
• Mid scoop control settings: Flat—(has slight midrange presence peak with feedback removed)
“EMish” – 15dB notch at about 1000Hz
“EFish” – 15dB notch at about 500Hz
• Tube complement: One EF86, one EL84
• Speaker: Weber Ceramic Signature 8S / 4 ohms impedance
• Input: One input on front
• Two outputs: External cabinet, rear and headphones, front (cuts out other speakers when headphones are plugged in)
• Variable brake: Rated for 15 watts into 4 ohms
• Variable feedback: From 0 to 20dB
• Chassis panels: 5052 aluminum with random brushed finish—made in USA
• Cabinet: Pacific Northwest alder—made in USA
• Transformers: Custom Bottlehead transformers– made in USA
• Fused IEC power cord entry
• Available in 120VAC mains only or 240VAC mains only versions
So in the studio or practicing at home you have a pretty neat set of features to play with in a combo amp cabinet that’s a little smaller than a briefcase.
About that cabinet…
One of the biggest hurdles Doc had to take on was how to incorporate the methods we had refined for laying out a kit that was simple to build, cost effective and good sounding. Several ideas came to mind and left with their tail between their legs. Then one day, while looking at one of our kit wood bases sitting on edge while it was being sanded, the idea struck. The cabinet was already there, it was just laying on it’s back! One panel on the front, with the speaker attached and the amp circuit built on its backside with the tubes protected but visible. One panel on the back, open for the speaker to breath and mounting the power transformer and output transformer (by the way, we design our own transformers and they are made in the USA, as are our laser cut aluminum chassis panels and Pacific Northwest alder wood cabinets). It makes a simple sandwich that is easy to haul to the studio and equally easy to get into to mod.
How’s it sound? Well, it’s tough to describe how an amp sounds. But we’ll try. The first word that comes to mind is responsive. Every player who has tried it so far said they loved the responsiveness of the amp. It can go from clean and jazzy to what we call Crunchy Tode, a nice single ended pentode crunchy goodness. The little 8″ Weber is a really nice speaker with a later crunch of its own, which gives a nice bit of control as you go in and out of overdrive, without knocking out the highs to do so. Oh yeah, and it has a very low noise floor. We’ve been building super quiet hi fi tube amps for years and we transferred that knowledge into this little amp.
The other thing that every player who tried the prototype said was “put me on the list to get one.” Maybe that is the best description we can offer…
Artists who have a Tode:
Ayron Jones, Ayron Jones and the Way
Tode Guitar Amp Demos
We’re going to find a range of players wto help you get a feel for the sound of Tode. For starters here’s part one of our new demo video featuring Mike Herrera and Jack Parker of
Tumbledown and MxPx:
and here’s part two-
Here’s a third demo, with our good friend Mino Christante playing his lovely Taylor acoustic electric
The next demo is by one of Seattle’s hottest new R&B players, Ayron Jones, playing a couple of Strats-
Next we have a something a little different. Did we mention the Tode is partly made of metal? Kevin Crew of Steelscape stopped by and served shredded Tode with his Schecter Damien 8 one day –
This is the amazing Art Khu, a brilliant jazz keyboard player and arranger, an impressive classical music composer and also a fabulous guitarist who has studied with the likes of Tuck Andress. Art is playing Doc’s Bottlecaster, the guitar that Jack Parker and Ayron Jones are playing in the second half of their demos. We plugged it into a restored old school Morley wah pedal and ran that into the Tode. We were going to use just a couple minutes of this 9+ minute long take, but it’s all so good we didn’t have the heart to cut anything. Get ready for some funky shit –
A lot of Todes are going to jazz players. Here’s Art Khu again with the Jacqui Naylor trio, playing Doc’s big homebrew jazzbox with a Johnny Smith style pickup thru Doc’s personal Tode. For those of you who are impatient, his solo starts at 1:48.
Here’s a video of our Bottlehead Tode Hop guitar player’s contest at Bainbridge Island Brewing Co. Each player got a minute or so to familiarize themselves with the Tode’s controls, then three minutes to play like hell. Man, the house was packed!
Is it easy to build? Sure, you just need to take your time. Assembly will probably be best done over a couple of evenings. Like all Bottlehead kits this kit is intended to be for someone who doesn’t read schematics and may not have built an amp before. It will come with a PDF manual chock full of high resolution photos to make the build easy, and builders will have access to the best tube amp kit tech support forum out there, the Bottlehead Forum
Impressions:
So I finished this soon after the first post, but I’ve been having too much fun playing it to take pictures and talk about it. This thing freakin rocks. The internal speaker is great for practicing and taking to a friends house, but this amp has some balls. Running it into my homemade 2×12″ cabinet I have to keep the brake at or below 3 on the dial lest I piss of my housemates. The EMish and EFish settings are spot on too, with the EFish setting perfectly channeling my 1972 Fender Pro Reverb with clear voice and bell-tones on top of chords. The amp is wonderfully dynamic too. I love setting the feedback right at the breaking point and playing softly on my guitar to get a nice clean tone and then digging in to set this thing screaming. I’m glad I have this external cabinet to allow for more experimentation too. It’s a clone of a Hiwatt with a closed back and a few vents in the back, but now I’m looking into a semi-open or even full open to get more treble and upper-mids. But I digress.
Way to go, Doc. You knocked this one out of the park. Now I just need to join a band so I can show it off all over town.
Maxwell_E, on the Bottlehead Forum
Wow, this thing sounds amazing!!!
My only recheck is the LED not lighting, which will probably be something stupid that I missed. Thing is, I’m too busy testing out every guitar I own through it, hehehe.
Another amazing home run guys… This little amp has sweet sound, and it’s got great punch.
willspeed, on the Bottlehead Forum
A new Tode in the world – Another brilliant Bottlehead kit!
Doc, This kit is another victory for you and your team! Boldly plugged in the strat and flicked the switch. The touch is so direct and sensitive, even at very low volume. Got those clean, chimey tones and some nice light crunch. This thing can get loud even with the single coils! Very versatile with the mid scoop control. I can’t wait to break in that transformer and speaker. Then we get out the Les Paul and some pedals! Thank you again for taking on this project, and all the years of sonic pleasure past, present and future. – Jeff
tcell, on the Bottlehead Forum
I’ve built mine and it sounds very good. The Fender tone setting sounds good with my pedal steel guitar (I don’t play no stinkin’ 6 string twangers!). The line out to my WGS- EV-SRO clone into a closed cabinet sounds great and darn loud too.
piperbob, on the Bottlehead Forum
I had some time this weekend to play with the amp to see how it sounds. I have an acoustic electric classical guitar and ukulele that both sound fantastic played clean through the Tode. I love the sound of the EL84 with my acoustic instruments– tone is full, clear, & warm, projects extremely well.
With the electric guitar, the Tode is extremely versatile. I really enjoyed experimenting with the Midscoop and being able to switch up the tone while keeping the underlying richness. I was able to get an amazing range of distortion between my guitar’s controls and the crunch setting on the amp. Between the sound and the satisfaction of building it, this amp is simply AWESOME! Thanks for another great kit!!
Doc,
I think you’ve really nailed this one! I have a feeling that this one will be a success with the broader musician community in addition to those of us more rooted in the playback side of things. It’s addicting… the more I play with it, the more drawn in I get! …Now if it could only help my technique!
Cheers,
Bill Chase, on the Bottlehead Forum
Just finished building my Tode, works perfectly, sounds very nice.
Dyna Saur, on the Bottlehead Forum
PS – No, the speaker cone is not about to catch fire in the photo. That’s our idea of an interesting pilot light.
PPS – the guitar in the background is our Bottlecaster, an alder Strat hardtail body by Mojotone with a short scale Squire Mini Strat neck and alnico V magnet single coils that have custom shielding. We added a custom random brushed aluminum pickguard and “mini” Bottlehead style knobs. That’s the guitar that Jack Parker and Ayron Jones are playing in the second half of their demo videos. We’ll try to get a few different players to play the same guitar on their demo so you can get a feel for how much influence the player has on the overall sound.
Please note, these initial production runs tend to sell out quickly. Your credit card will be charged the day you place your order. We estimate a four to six week delivery time for these early run kits.