[Blackcorvo] wrote in to tell us how he took a cheap “retro” guitar amplifier and rebuilt it with sub-miniature vacuum tubes. The end result is a tiny portable amplifier that not only looks the part, but sounds it to. He’s helpfully provided wiring schematics, build images, and even a video of the amplifier doing it’s thing.
The original Honeytone amplifier goes for about $26, and while it certainly looks old-school, the internals are anything but. [Blackcorvo] is too much of a gentleman to provide “before” pictures of the internals, but we looked it up and let’s just say it doesn’t exactly scream high quality audio. Reviews online seem to indicate it works about as well as could be expected for an amplifier that costs less than $30, but this is definitely no audiophile gear.
Powering up the miniature vacuum tubes takes a bit of modern support electronics, including a buck converter to provide the high voltage for the tubes as well as a 6V regulator. The plus side is that the new circuit can power the tubes from an input voltage between 12 and 30 volts, meaning the amplifier can still be powered by batteries if you want to take it on the go.
We’ve seen some fantastic tube amplifier builds over the years, proving that some things never go out of style. If you’d like to learn more about the magic that lets these little tubes of hot pixies make beautiful music, the US Army has you covered.
Good Lord, it’s cute and sounds incredible!
I knew this wasn’t going to be “audiophile” as that’s not what you want anyway. Really good sound!
Nice gobs of even-harmonic distortion.
Schiz? I have sacks full of these kind of tubes.
You don’t want audiophile in a guitar amp. Everything from the pickup to the speaker colors the sound and is meant to. Ever heard an electric guitar through a stereo system, straight through? It sounds horrible!
But, most electric guitarists DON’T want the CABLE to color the sound!
B^)
Supposedly a cheap boombox is how Varg got the guitar tone on Filosofem.
https://www.youtube.com/watch?v=DPyOhP1GTRQ
Along with cracked cymbals and drums with holes in the head.
That being said, I like your use of filosofem as if its common knowledge!
I think… http://batterypoweredguitaramp.com/danelectro-honeytone-guitar-amplifier/ might be the same amp with the original guts for comparison. Not exactly high sophistication in construction there.
Yeah, wow. The original guts were numbingly pedestrian compared to the gorgeous old-fashioned components and construction style it has now!
Thanks for the comparison, that makes the project even more interesting.
I happen to have another Honeytone Amp, still intact save for a speaker out mod. I coud make a video sometime soon showing both side to side, sound difference, etc.
Pretty sweet. Way to get it all shoehorned back in there.
Should try Korg tube next time
https://youtu.be/8MJ8XEzkfnY
Stay tuned, I’m in the process of designing ‘yet another headphone amp’ with the Nutube which should bear some fruit by the end of the year. (Just got my hands on a HP 8903B to see how well it performs too!)
While those KORG NuTubes look neat, the circuit is more complicated than traditional tube circuits, as each triode requires a buffer at their grids since they have very low input inpedance. Also, they’re a tad expensive at the moment if compared to subminiature tubes. But I do love this new tech they came up with, and I hope to someday get my hands on one of those to try out myself!
They suffer from terrible hum :(
NICE….. Sounds great !
Is there a parts list?
Maybe Tom doesn’t realize that the link at the top is just to the same youtube video?
Not really. But if you click through to the YouTube page, hit “more info” or whatever, you’ll find the schematic with all of like 12 components.
Seems like the YouTube video is all there is, but he does have schematics and a diagram that shows all the parts.
Here you go:
Parts List
Resistors (all rated at 2w, because of size rather than heat dissipation):
1x 330R
1x 1k
2x 1k5
1x 3k3
3x 68k
1x 100k
1x 220k
2x 1M
Potentiometers:
2x 500kA (Gain and Volume)
1x 500kB (Tone)
Capacitors:
1x 100p 50v
2x 4,7n 250v
2x 10nF 250v
1x 0.47u 50v
1x 22uF 50v (6N21B b cathode)
2x 22uF 250v (B+ nodes)
1x 220uF 50v
Output Transformer: 3K:4R/8R, 1 Watt, 120Hz low-end cutoff (custom-made for this project by http://schatz.eng.br
Voltage Conversion Boards:
B+ https://m.ebay.com/itm/263382388214
6V https://m.ebay.com/itm/183032224901
Thank you very much for the parts list I have the same Honey tone Amp but I am going to build this Amp into a repurposed wooden index card holder so I can include a bigger speaker
The 5902 valve has interesting shock characteristics. I suspect that the design life of these tubes could be measured in seconds in the intended applications.
Aaargh! I said tubes! They are VALVES.
I can’t believe you guys actually featured my build! Thanks a bunch! If there’s any questions about it, I’m here to answer them.
Yes. Why haven’t you made this available as a drop in kit yet?! (= No, seriously, how much for a drop in kit?
I wouldn’t know how much such a kit could cost, considering the tubes aren’t produced anymore. They’re not expensive or hard to find by any means, but they’re not too widely available either.
And the output transformer would need to be custom made.
And I’m in Brazil, which would make shipping it to overseas customers a nightmare because:
1. The Brazilian mail service is slow;
2. They often “lose” packages;
3. They also often mishandle packages;
4. Shipping might be more expensive than people are willing to pay for.
If it weren’t for that, I’d get right on making kits of this. I’d love to see people making them!
Small update:
– Changed High Voltage board for a smaller one: https://www.ebay.com/itm/141728332617 (seller “VFDClock”) ;
– Increased the cathode resistor on the 5902 to 1k, due to higher B+ (170v) ;
What songs do you play on the vacuum tube amplifier well the tube amplifier is tubeway so some tubeway army songs and gary numan we are glass a song about glass vacuum tube we are so fragile the valves are delicate I dream of wires the old days of point to point wiring before printed circuits if transistor amplifier has direct coupled transistors one transistor dies and kills the other ones in circuit in song I die you die and high voltage supply for valvedcand its are friends electric if you get an electric shock in the modern solid state age tube way days now seem so unreal