I especially love how you turn the pot backwards to get higher volume :D

@UsagiElectric

3 жыл бұрын

That was actually the first thing my father commented on upon seeing it, haha. It was totally a result of me just trying to find a good way to draw the traces on the PCB and completely not thinking about which way the potentiometer turns.

@davidkclayton

2 жыл бұрын

For me I would have dispensed with the volume control use the volume control on the source and keep it stereo also if your speakers were sealed the board you might save a bass Improvement

@ErwinBeukhof

2 жыл бұрын

Just call it the attenuator and you're good to go 🙂 Great build!

Nice little amp and construction technique. But oh, that jazz track, I might re-use that!

@UsagiElectric

3 жыл бұрын

Thank you so much! OCRemix has a ton of great music that can be used, they're a fantastic site! I'm a bit partial to jazz remixes of Square Enix titles like Chrono Trigger and Final Fantasy myself.

@heyitsandrew2209

3 жыл бұрын

@@UsagiElectric A legend watches you! CuriousMarc is THE GURU

@UsagiElectric

3 жыл бұрын

@@heyitsandrew2209 Marc is an absolute legend and I'm convinced there's not a single piece of electronics equipment he can't repair! CuriousMarc and Ben Eater are the two KZreadrs that I drop everything and watch whenever a new video drops!

@CuriousMarc

3 жыл бұрын

@@UsagiElectric Hmm, Ben Eater, eh. Now I finally understand why you are breadboarding with tubes! That said, I am sure taking breadboards a lot more seriously now that I have watched his videos.

@UsagiElectric

3 жыл бұрын

@@CuriousMarc Between the two of y'all I've learned more about electronics (and teletypes! - I still need to get to work on my Model 14) in the past year than I have in the past 20 years of tinkering! Also, I quite enjoyed watching you build a TI watch on a breadboard and then interfacing that with the HP boards!

Hey just felt compelled to let you know that your content specifically is really well-made in regards to pacing and your delivery of ideas, developments, and rhetorical questions/thoughts to bring us along your thought process step by step as you figure things out. I both feel like you're teaching me and learning yourself, and it works great, man! I've been working through vacuum tube projects myself, and finding your channel was somewhere between sitting in on an undergraduate TA study session in college catching me up on concepts I missed in lecture and comparing notes on semester projects/homework with a really smart friend. Keep up the good work! Your channel makes a lot of archaic stuff really accessible and its a true delight to be along for the puzzling things out~

Love the results from your design. And I agree, it looks amazing! Great Job!

This is an absolutely cute awesome little tube amplifier. I enjoyed this build a lot and learn an awful lot during your videos. Thank you!!

@UsagiElectric

2 жыл бұрын

Thank you so much, I'm glad you're enjoying the videos!

This is the Upcycling I LOVE! Keep up the good work! My favorite little channel right now. You make me want to start one and tinker.

@UsagiElectric

3 жыл бұрын

Thank you so much! If you do start a channel, let me know! I love checking out other's projects (it's a fantastic way for me to "borrow" ideas, haha). If you'd prefer to just share some pictures, join us over on the Discord server. There's some brilliant people in there that could offer insight and feedback.

I see that you stumbled upon one of the cardinal rules of psychoacoustics ; The louder the signal, the better we percieve the tone to be, and about 1K is the main EQ/ frequency we hear, so higher and lower frequencies are percieved to be of lower volume, and we hear less "tone" ( highs and lows) compared to the bulge in the mids. This means when the whole signal is louder, you hear more high treble and low bass, so it's percieved as more tone. Your audio results depend on the speakers as much as the amp, and you spent all your time and mind on the amp, fitting some random speakers as an afterthought. I can guarantee you that if you did a swag of reseach and looked at speaker enclosure designs and which drivers are fitted to which cabinets, whether to have open enclosures, ported boxes, or completely sealed units, and so on, that you would make s forty percent noticeable improvement on the sound you already have. I can guess that you build this stuff for fun and curiosity, so perhaps I'm not helping by trying to drag you into the rabbit-hole of addiction to fine audio, but maybe you'd find it fun too!😄

Sealing the back of the speakers off from the front will improve the bass response. They are meant to be mounted flush with the baffle so the basket openings aren't so close to the front of the driver. Super cool project!!!

@UsagiElectric

2 жыл бұрын

Thank you so much! There are definitely a lot of compromises in the design that were made so the end product would look cool, haha. I do really want to revisit an audio amplifier in a future project though, so hopefully with that one we can get some proper sound out of it!

Awesome build, the final product looks fantastic! I love the "How it's Made" vibe, watching the mill at work is mesmerizing. Great camera work too :) If you don't mind me asking, what would the total BoM come out to if one were to build one of these themselves?

@UsagiElectric

3 жыл бұрын

Thank you so much! Oooh, it’s hard to judge total cost involved in building this because so much of it was made out of spares I had laying around. The PCB is one of the more interesting ones to try to figure out, because the CNC 3-axis mill I use isn’t exactly cheap, haha. But, you could get PCBs made at one of the reputable PCB manufacturers for decently cheap. My PCB measures 100mm x 150mm, which looks to cost around $50 for five of them from PCBWay. However, I chose that size because it was what I had on hand already. With a double sided PCB and some clever redesigning, you could easily get that size down to something like 75mm x 75mm, which brings the cost down to $25 for five boards. The capacitors were all leftover stock from when I restored our old Magnavox Concert Grand stereo, but at these low voltages, capacitors and resistors are all super cheap. The 12BH7 and 12B4A tubes are probably going to be the most expensive. The 12BH7 is about $10 a piece on eBay with shipping, and the 12B4A is about $8 a piece with shipping. But, those aren’t the end all be all of audio tubes. There’s a lot of options out there for dirt cheap tubes that could be made to work with the right resistor and capacitor values. But, to rebuild this one, as it is, here’s about roughly what it would cost: PCB: $50 Tubes (2x 12BH7, 2x 12B4A): $35 Capacitors, resistors, potentiometer: $10 Mini output transformers (pack of 10): $10 Mini speakers (Gikfun EK1794): $10 Total: $115 Which is ridiculous now that I type it out, haha. But, get that PCB size down and grab some cheapo tubes and that price can come way down. Also, spending $35 for those specific tubes isn’t the greatest idea. You can find tube lots of random tubes on eBay for cheap. For $35 you can get a random lot of around 100 tubes, which is way more bang for the buck! You can also find lots of good tubes in smaller numbers for much cheaper as well. Currently, there is a lot of 8x 12AT7 dual triodes on eBay for $15, which are good tubes. So you could easily order enough parts to build two of these amps for about $50 to 60!

Thank you for sharing, very interesting and informative, just uploaded a few of my hand crafted tube Amps. I enjoy learning more about the world of tube Audio!

@UsagiElectric

2 жыл бұрын

Thank you very much! Your Type 42 Single Ended Amp has a beautifully compact construction! I also really like using the large copper wire as sort of bus bars for the point to point wiring on the inside. Very nicely made amplifier!

I'm happy to see that there are someone else that spends a few moments extra on making curved tracks instead of the plain 45/90 degrees ones. When I know that I'll want a curved look on the pcb I usually route it all with 90-degrees bends and then as a final pass go over it all and redo the corners.

@UsagiElectric

3 жыл бұрын

I love curvy traces! I know that when it comes to really high frequencies, there's some issues with curvy traces and 90* bends work better (although I haven't really read into why), but nothing I build will ever operate at those high speeds, so the primary focus becomes making the board look good, haha.

@urnoob5528

5 ай бұрын

@@UsagiElectric u literally said the wrong thing it s opposite curvy is better than 90 degrees 45 degrees is a compromise

Lovely. Good job. Nice use of CnC also.

Cool amp - I hope you're using mystical audio cables to enhance the sound :) I like the shirt too! I had a 180B SSS and then a 1600.

Thank you, very interesting. Well done. 🙂

@UsagiElectric

2 жыл бұрын

Thank you for checking the video out!

Love your design and it's beautiful turnout! I would like to give it a shot, however I would like to try the stereo route. What modifications would you suggest I make? Thank you.

@UsagiElectric

2 жыл бұрын

Thank you! It pretty much already is a stereo amplifier. If you look at the schematic at 2:10 in the video, if you put the right channel into the right input and the left channel into the left input, that'll make it stereo. You'll need either two volume potentiometers, or a ganged stereo potentiometer. I didn't have a stereo potentiometer, which is why I decided to force mono through it. But the design itself is essentially already a stereo design!

I am curious as to whether any consideration was given to matching the primary impedance of the output transformers to the plate resistance of the output triodes. This match is a very, if not the, critical design criteria for transferring power from an output tube to a loudspeaker. Also a significant mismatch here will be reflected into the transformer secondary, which of course needs to be matched to the voice coil impedance. If you need to chase maximum output power and low distortion, start by using a transformer with the closest match to the output tube you can find.

@UsagiElectric

2 жыл бұрын

Haha, there wasn't any consideration given to matching anything! I just threw whatever parts I happened to have laying around at a breadboard and trail and error'd my way through values until I started to get a sound I liked. With some proper parts matching and designing, this amp could definitely sound a whole lot better!

I love it! BTW, what is the ratio of the little output transformer

Sweet project! Any chance you could post a schematic for this? Would love to play with some tubes without risking the high voltages found in other approaches Thanks for fascinating videos

@UsagiElectric

3 жыл бұрын

Thank you very much! Sure thing: i.postimg.cc/L5f6j0SW/002.jpg It's essentially two duplicated class A mono amps sitting next to each other, so really only one needs to be made. And, with some better output transformers and a bigger speaker, you should be able to get some decent sound!

I wonder if you could have an advantage of putting one side of the power amp to one speaker using only a narrow band of low frequencies and let the other power amp and speaker carry the rest. Ive used this concept many time in live sound with great results. Its shocking sometimes how big a sound you can get from a small system this way. I realize this would have added more complexity with having to add a crossover circuit . Your videos are addictive, thanks for the work you gave us.

Nice project! I am looking into building a tube guitar amp but dont feel like messing with high voltages so im glad ive come across your videos. What amount of power do you think it puts out? Do you think it could drive for instance a 3 inch speaker for a bit of bedroom jamming?

@UsagiElectric

2 жыл бұрын

Honestly, it's a really small amount of power. If I had to guess, I would say between 0.5W to 0.75W-ish. It might be a little too quiet for a good guitar amp. But, a hybrid amp could work really well. Using some tubes as good pre-amplifiers and to set the tone, and then a final solid state driver give about 3W of output power could be quite good! Or, it might be worth bumping the voltage up to 54.6V, that should get you around 1W of power output, which might be a decent enough volume without upsetting the neighbors. And 54.6V supplies can be found on Amazon for really cheap, while still keeping the voltage relatively low. I think I'm going to revisit the low voltage tube amp sometime in the future and see if I can get a bit more and better sound out of it!

@ronb6182

2 жыл бұрын

We need to get these hi voltage fears out of some more advanced electronic hobbyist. I would say forget the circuit board and hard wire using color coded wire. Use red wire for the b+, use green wire for the tube heaters, use black and white wire for the primary, if you use a tube rectifier use yellow wire for the 5 volt filament. Ground or chassis ground use green with a black stripe stating it's the power ground. The red, green and yellow are what the tube manufacturer used when building early tube radios and amplifiers. Care should always be taken when working with any electronics. Low voltage can still kill, it's the current that kills not the voltage. Power transformers are hard to find so you can use a foreign transformer that takes 240 and steps down to 120 Volts. Just put the 120 volts in the output and use the input side for the 240 b+ a step down transformer can also be a step up transformer. You can also use a voltage multiplier circuit using diodes and capacitors if you use ac for your transformer instead of a dc power supply. AC can be multiplied into DC, old television sets that didn't have a transformer used these circuits. I would never tell anyone to multiply the AC line voltage. Too dangerous even though tv manufacturers did that practice. Only double 24 or 48 volts. 96 Volts will give a good shock. Play it safe use a transformer on tube projects.

Awesome amp! What did you use to turn the PCB into a tube socket? Was there something you soldered into the holes? I want to use that technique someday. These covid times are perfect for building projects. I just finished building a tube theremin.

@boutinclovis4233

3 жыл бұрын

Hi, can't wait to see the tube theremin on your channel :)

@UsagiElectric

3 жыл бұрын

Thank you so much! For the tube sockets, I actually just use little 1mm PCB receptacles (link below). They have a 1mm inner diameter, which is perfect for 7-pin and 9-pin tubes. The outer diameter is about 2mm though, so in DesignSpark I just made a pad with a 3mm OD and 2mm ID (in order to get my mill to cut the pad correctly, I added a board hole in the center of the pad, but that was something specific to cutting on the mill). The only downside to this method is that if the tube runs hot, quite a lot of that heat gets transferred into the PCB. For the smaller 7-pin tubes like the 6AU6, this isn't a problem at all as they never really get all that hot, but the 12B4A I used here seems to run really hot. So much so that you can't touch the glass after it's been on for a while. So, I may run into PCB reliability issues on this amp in the future if I run it for several hours at a time. That was a sacrifice I was willing to make for the aesthetic, haha. PCB Socket: www.mouser.com/ProductDetail/855-H3161-46 A tube theremin is one of those projects I actually got super interested in after playing The Outer Worlds! There's a tube theremin schematic floating around in some areas of the game. I had never really heard of a theremin before then, but now I think they're epic instruments! I'm looking forward to checking out the video on your channel! Tube Theremin in Outer Worlds: www.thereminworld.com/Forums/T/32677/spotted-in-new-game

Is there a small supply for filaments below the PCB ? Or you run the filaments in series on plate voltage with a big dropper resistor ?

@UsagiElectric

3 жыл бұрын

No extra supply! The heater filaments are run in series off plate voltage, but because each heater each tube is a 12V 300mA heater, they can run in series off 48V without needing a dropper resistor (12V x 4 tubes = 48V). Matching up heater voltage and amperage requirements is actually the primary reason why I chose the 12BH7 in this design. Also, physically larger tubes means more plate surface area, which should mean more electron flow and hopefully a higher volume!

This would be awesome for a mic preamp to add some saturation to vocals and have not sound as sterile and a bit warmer and natural. awesome vid!!

@UsagiElectric

2 жыл бұрын

Thank you so much! Yeah, it's not a great setup for room level audio, but it would be really interesting for microphone pre-amp duty! I do have some more audio projects I want to work on, including a microphone pre-amp, so once I finish working on the old HP test equipment I'm currently trying to restore, I think I'll take another stab at getting some decent audio quality stuff going on!

Those 474nF cathode capacitors are a weird choice? For max power you want to fully bypass the cathodes at all audio frequencies, so with a 100R resistor you're looking for 100 *micro* farads or more.

@UsagiElectric

3 жыл бұрын

Honestly, the values I came up with here were discovered purely through trial and error. I built up the circuit on the breadboard and then swapped resistors and capacitors for about a week straight, trying all sorts of different combinations of values until I found a combo that produced the best quality sound. But, you may be on the nose here! I don't really know much about audio circuits, so this was a massive learning experience and I'm sure there are better resistor and capacitor combo values that I totally missed!

That's a nice result! Thank-you. 🙂👍 There are several things which you could do to make it sound better and louder, if you want to experiment further. Use a pair of, say, 6" x 4" midrange speakers. (They were used a lot in cars, some years ago, so they can be found at scrapyards for low prices.) They will be more efficient and produce some Bass notes. Increase the low frequency output more by using larger value coupling capacitors. Pick a pair of better quality output transformers. They do not need to be huge. Use a twin triode on each output stage, but wire them in parallel. Increase output tube plate current to the maximum. Run the final stage of each amplifier in Class B instead of Class A. Class A is at best 25% efficient, but Class B can be more than 33% efficient, and can approach 50%, giving you twice the output power. You could also run the output twin triodes in Push-Pull configuration, instead of in parallel, using a tapped transformer on the two grids. If you really want to increase the output level, then think about running the outputs in Class D or E and pulsing the tubes at an ultrasonic frequency whilst carrying the desired audio. That can give you several Watts of peak power, albeit with a small increase in distortion if you push it too far. For reference, in a transistor circuit, using a BC109 NPN Silicon transistor, which is rated at 200 mW continuous dissipation, I have seen one delivering several Watts (6 if my memory is correct) of perfectly acceptable audio for casual listening, using that method, with no heatsink on the transistor. That's enough for comfortable music listening with similar frequency response to a broadcast radio, in an urban lounge, if you're not an audio purist. A similar idea has been used in megaphones, but using a high efficiency horn. That horn is designed for speech only, with no consideration to fidelity; hence the distinctly low-fi sound from them. Your amplifier will sound better than that, because of the better speakers.

@urnoob5528

5 ай бұрын

or u know bias the tubes correctly(im guessing he just eye balled the resistor values) and actually get them into the linear region the reason he got better sound by using higher voltage is because tubes need tens of volts to get into the linear region, for bjt this is like around or less than 1v also class b can be 53.5398% more efficient, because class b is at best pi/4*100% efficient but really these numbers 78.54% or 25% are crap talk, real amplifiers will never reach these at best also wtf u mean small signal transistor delivering 6w, either thats wrong or thats way out of their specification, even in class ab u have to use power transistors with a mid sized heatsink to get that power also casual listening is more like 2w for me which is already loud enough, 6w would be WAY TOO loud, at least for my speaker also class b is really gonna complicate things a lot especially in tube design, the idea was to make simple tube amplifier no? no? ok then maybe he could also add some negative feedback class d!? now we just addin silicon back in, comparators and watnot, thats more more complex(unless we tryna design differential amp with tubes? wat is this a room sized amplifier?) class d isnt just about the output, it s a whole topology, everything from input to output gon be different at this point just use opamp use a single tube for preamp, for that tube sound if u know wat i mean and run the whole thing in solid state

It would be interesting to run it into some very efficient full range drivers, externally

Sweet!!

@UsagiElectric

3 жыл бұрын

Thank you!

You should install some 5 way binding posts on the back, to hook up to some efficient speakers! Like your design!

@UsagiElectric

2 жыл бұрын

Thank you! It's really just a super simple copy of the Champ Amp design, though I made a lot of mistakes on this one that can be done much better. I recently did another amp only without the Output Transformer and it sounded much better, but I do have another amp planned with a bigger speaker and better output transformer that should be a whole lot better than this one!

Hi very nice build.....I got bunch oh 12ax7 tube, is it possible using this diagram to build with 12ax7 tube?. Of course it need some change on the diagram but I'm not to good in electronic, need some advise. ^^

@UsagiElectric

3 жыл бұрын

Absolutely! The 12B4A i use here for the driver tube could easily be replaced by a 12AX7, but I would run the two triodes in parallel to get a little more power out of it. Of course, the resistor and capacitor values will most likely have to be tweaked to get good sound out of it, but it's totally doable with four 12AX7 tubes! If you want, come join us over on the Discord channel, there's a ton of people there that are way smarter than me with audio circuits, and we'd be happy to help you build up an amp! ( discord.gg/p7UsfHD )

Neat design. What is the turn ratio on the transformer and the impedance of the speakers? Also, since it's based on the Fender Champ, I would be curious to hear the output when driven from a guitar pickup...

@UsagiElectric

2 жыл бұрын

Thank you! Not a clue on the output transformer, they were just random little transformers I found on eBay. I imagine they're only meant for voice or something simple in devices like modems, and I'm way misusing them here. It would definitely be interesting to hear what it sounds like with a guitar, unfortunately, I don't own any guitars, haha.

@brianclimbs1509

2 жыл бұрын

@@UsagiElectric Thanks! I always assume that if I design something, it won't work because I will mess up the impedance matching or something. I'm really interested in designing an easy to build, low-voltage, tube amplifier or radio that uses tubes that are still manufactured today (like the 12AX7 or EL34). It would be great if there were more options for people to learn about using vacuum tubes that doesn't depend on vintage tubes, because as soon as a vintage tube gets popular, the price goes up (like all the Nixies).

@alexm4104

6 ай бұрын

@@brianclimbs1509if you have found some schematics or more materials about that can share please, i'm interested in make e lov volt tube amp for guitar/bass

ok so, if i were to build an amp based on your design, what kind of transformer should i use? that seems to be the hardest part to figure out on a tube amp. will something like a 600ohm 1:1 transformer work? awesome vid btw, simple to understand

@El_IrregularDX

5 ай бұрын

ooh also is it possible to use the 12AX7 instead of the 12BH7?

You could build quarter wave transmission line tubes for the drivers, that would get you a much better range.

Of course when the voltage goes higher ... hope you insulate and isolate yourselves ... may be 48v is ok. but the last 24v is better may I say and more accessible.

I have just come across your channel (Episode one of the build).VERRY impressive all round As the owner of a fairly expensive sound system built around an integrated valve amp, I tell people that I did not spend all that money to improve my normal volume listening but so that when I tern it right down the music still sounds as complete just lower. I'm shore you can imagine haw much I would like to hear your amp (real world) I think you could improve the base greatly by some sonic wave guide Infront of ,or projecting around the speakers.(Have a look at the grills the manufacturers like to boast about Shh)

very cool ,do you have a list of components, might be cool to build a copy of that :)

@UsagiElectric

2 жыл бұрын

Thank you! I don't really have a list of components as it was just built from stuff I had laying around. The tubes in use are 2x 12B4A and 2x 12BH7. The output transformers are just random ones I found on eBay years ago and there's actually a lot better options out there. Other than that, it's just whatever resistors and capacitors I had laying about that sounded good through trial and error!

That amp is beautiful.

@UsagiElectric

3 жыл бұрын

Thank you! I'm really loving the solid wood block for the base. The fact that there aren't any seams on the wood just makes it really cool. Plus it gives the amp a great solid feel. Unfortunately, I caught my jacket sleeve on one of the 12BH7s the other day and broke the base, so it's currently waiting for me to hunt down another 12BH7 to replace it.

@frankowalker4662

3 жыл бұрын

@@UsagiElectric That's crappy. Easy to do though, the weakest point is where the pins go into the glass.

@UsagiElectric

3 жыл бұрын

@@frankowalker4662 Yeah, I seem to have bad luck with the 12BH7s on this amp. That's the second one I've broken in less than a week!

hey quick question, how come some tube amps got some large capacitors and some don't?

Nice sounding little tube amp....The real tube Challenge is achieving same or Louder volume on just 12 volts DC.... The 12K5 power Tetrode kicks out Amazing volume on just 12 Vdc plate & Screen....The loudest Clean sounding all vacuum Tube amp design makes an interesting Safe low Voltage Challenge project !!

volume is about moving air. You need larger and probably higher efficency speakers. How would the design change when using say 6" speakers? Would you need different OT's? Do you see yourself revisiting this project with an aim to not just annoy the wife but overcoming the din of a party at your apartment? I know this is an older vid but just now seeing it. Thank you.

Absolutely awesome project. Maybe I will get started with vacuum tubes on lower voltage. Hope Soviet made one’s will be fine.

@UsagiElectric

2 жыл бұрын

Thank you! Most tubes work really well at lower voltages, but some of the soviet tubes may not move enough current for good volume at low voltage. The 6N2P for example moves a bit less current than the 6N1P, and both move considerably less current than the 12B4A used here as a driver tube.

@malcolmholmes115

2 жыл бұрын

@@UsagiElectric thank you for reply. Maybe I will try find a Soviet equivalent to your tubes, since almost everything in Soviet Union was stolen from west 😁 I really appreciate your channel, it’s one of my favorites now, since it’s very hard to find good information about vacuum tubes. Just keep going, I think your channel is underrated now and I hope you will have more subs soon. By the way, I want to make a channel about unique and interesting Soviet tech, such as this tiny Soviet buttons, but in English. Does it sound interesting? I will get started with my workshop when I come back to Russia from Indonesia, in March, hopefully.

@urnoob5528

5 ай бұрын

@@UsagiElectric most tubes work really well at lower voltages IF they are for switching application MOST TUBES absolutely do not work really well at lower voltages for audio due to them not even getting into their linear region they will work, but definitely NOT REALLY WELL but i guess that would also depends wat u define as lower voltages tubes need tens of volts to even get into their linear region, like 40v and above(for most tubes) and ur signal cant swing below that, or distortion, imagine say 30v and u get into linear region, and u use 36v supply, ur signal has that 6v room to swing without being distorted thats why using 100v, u r well into the linear region, the signal have a big room to swing, and not going below 30v

One mod to the basic design that I could suggest is maybe add a speaker out jack to each of the two amplifiers so you could connect them up to a pair of HiFi speakers.

@UsagiElectric

2 жыл бұрын

That's a good idea! Though there's certainly not enough power available to drive a good set of HiFi speakers, but it would make for an interesting pre-amp design to a HiFi setup!

Yeah.... milling a pocket out of an old beat-up piece of wood was a terrific idea... it gives it a perfect "yesteryear" feel.

I'm inspired to use this for either a Preamp or a Headphone amp. I got a ton of Power Transformers that should work for it. Wonder how well 60Volts will do. I think I also have some Transformers from some old switch mode power supplies that could work as output transformers. Although I do have a couple of tricks up my sleeves for that part.

@UsagiElectric

3 жыл бұрын

This design would make an excellent preamp/headphone amp, though as a headphone amp, you might be able to get away with a lower voltage. With 60V and a good driver tube, you should be able to get about 10W of power out of it, which should make a great amp for an apartment!

@tortugahispana

10 ай бұрын

@@UsagiElectric consider raise resistor watt values.

Nice little amp they make supercharged tubes the are made for 12-15 bolts for plate 12v fill.My personal Amplifers are push pull Ulteralinear 813 tubes @ 200 volts 500ms. 6sl7 preamp phase inverter with 6sn7 drivers all paper in oil dog caps.of course 6AU4 tubes for power supply. I really enjoy your channel 73 W3AMG

Actually you could drill down under the speakers 3/4 of the way, drill into the back of the wood to open that channel. Then roll up some paper into 2 cones and with a small end sticking into a hole and the big end coming out. There’s a number of ways to cheaply build something around the speakers, get 2 small Dixie cups or those plastic pepto bismuth serving plastic cups, cut the bottom out so your speaker fits inside then attach the new speaker where the old one was. I’m sure you could make something even better some kind of wire covered or attached to thin rubber to make a slider and the speaker inside of that. Makes ya think

@UsagiElectric

2 жыл бұрын

Ooh, yeah, that's actually a really good idea! I was kind of thinking that the open space between the PCB and wood enclosure would work as a sort of speaker box, but you're right that he speakers need a better, more dedicated enclosure. Audio stuff is so weird and difficult for me after having spent so much time thinking in a digital computing way with the tube computer I'm building. But, I have a new audio project I'm slowly working on, so hopefully we can get a pretty wild little tube audio project going soon!

i need a help.i have EAF801 tubes. can i use this curcit for them. can you help me to learn about vacuum tubes.

@UsagiElectric

3 жыл бұрын

Hello! The EAF801 is a pentode, so it needs to be connected a little differently, but they should work pretty well as audio tubes! You'll also have to adjust resistor and capacitor values to match the tube as well as the voltage you're running, but the overall Fender Champ Amp design is really versatile and simple. If you want, come join us on the Discord chat server ( discord.com/invite/p7UsfHD ), there's a lot of really smart guys in there and we should be able to help you get an awesome tube amp going!

Wonderful build! As a point of safety, please push the radial arm saw through the material. There is no need for the extra care required to pull it.

Technically, you have two 'identical' amplifiers that are driven by a common input. It's worth pointing out that each output 'channel' is, to all intents and purposes, independent (although you've 'chosen' to connect one side of each transformer output winding to ground). Have you considered using this setup as a 'push-pull' amplifier? 1: Leave the LEFT transformer secondary winding exactly as it is 2: Disconnect the 'ground' wire from the RIGHT transformer secondary winding and move it to the other side of that winding. (This forces the originally 'grounded' end of that winding to now have a 180 degree phase shift from the LEFT transformer). 3: Connect a single speaker between the two 'non-grounded' secondary winding pins Obviously, doing this will change any transformer-to-speaker impedance, but I doubt it was anywhere near matched to begin with. Since the voltage potential across the speaker is now effectively doubled, you should hear a few dB of audio gain BTW, I am going to 'challenge' you to maximise the clock frequency of your UE14500. With surprisingly little 'tweaking', I'm betting you could get somewhere between 10kHz and 100kHz to operate stably. (All you need to remember about speed is "Capacitor BAD, Inductor BAD, Resistor OK")

If possible I wish you commercialise this and offer this board+ a guide.

@gerardcousineau3478

3 ай бұрын

And yep when build properly a tube amp sounds better than any transistor. I'm kind of a guitarist I had quite of few amps in my life. One of the few was a 1965 lifco very basic amp three lamps. I played in the metro with this one and you can see and feel the joy the people experiment with a sound so much warmer than transistor. Finally me too, one of my ear is dimmer than the other. And yes we can still appreciate stereo sound. But surprisingly if I remember well Brian Wilson of the beach boy was deaf from one ear. It didn't stop him for being a great musician and composer. Thanks for these videos on audio amplification with lamps. 🙂🐑🕊️💯

the piano in the background is fantastic, who is playing that?

@UsagiElectric

2 жыл бұрын

That is the brilliant Shnabubula! Trigger Please by Shnabubula: ocremix.org/remix/OCR02575 Chrono Moonstone by LSD: ocremix.org/remix/OCR01797

Its a PSE or Parallel Single Ended amp

@UsagiElectric

3 жыл бұрын

Interesting! I hadn't heard of a PSE amp before (I'm a total audio amplifier noob). I'm still a little confused on them though. Can it still be considered a parallel single ended amp if there's two output transformers and two speakers? From what I've read, it looks like a PSE uses two driver tubes in parallel to drive a single output transformer, essentially letting class A amplifier drive double the power it could with just one drive tube. This one here looks to use four tubes in parallel as driver tubes: www.audiodesignguide.com/my/el34_pse/newsh2.jpg What I built I feel might be closer to two full fledged, but completely separate amplifiers, being fed the same audio signal. Which, now that I think about it, is a terrible design, haha.

Make a little enclosure for the speakers and you’ll gain a ton more frequencies

The tubes will preform better as you get closer to their design voltages.

Transformator using?

@UsagiElectric

3 жыл бұрын

Hi, I think you're asking what output transformer I'm using? They're just some random tiny ones I found on eBay years ago just searching for "Audio Output Transformer". They actually were a pretty terrible choice for this application for everything other than their size. I could have gotten much better sound and more volume using a proper audio output transformer, like one from an old PA system.

Im sorry,, what the power tube?

@UsagiElectric

3 жыл бұрын

I'm not sure if it's the right way to refer to it, but it's the vacuum tube used to drive the output transformer. In this design, the 12BH7 dual triode is setup as two amplifier stages, and the 12B4A single triode is used to drive the transformer.

Amazing! Yet, should have used the negative feedback from the previous video.

How much Watts IT produce ?

@iikatinggangsengii2471

7 ай бұрын

the tm7 was like 150$ gr7 was 180 if, this is just if and guesses since i def dk nething, they really planning 200$-ish limited anv series itll be better than mext and competes with dt1990, but well see

Thanks this will bring more tube projects to the electronics field. I'm not afraid of the b+ I been playing with tubes since I was in seventh grade. I was named electronic genius but was far from it. I had my brothers radio servicing book that explained how old tube radios were built even the ones that used electromagnetic speakers. The amplifier is the same, all radios have an amplifier in them. Tuners have external amplifiers if they are considered to be a radio.

@UsagiElectric

2 жыл бұрын

Thank you! That was the hope with this project. A lot of people who grew up in the digital era, myself included, can be quite leery of voltages above 100V, but a good tube amp is often using a B+ three of four times higher than that. I never got into tubes because of the fear, but using them at low voltages gave really interesting results and opened the door to start learning about how to conquer that fear!

@ronb6182

2 жыл бұрын

@@UsagiElectric it's all about color coded wires use red for B+ and green for fillament (heaters). If you use a vaccum tube rectifier the filament wires are yellow. The plate wires are already red off.the transformer. 73

i'd be interested in hearing 60 volts could do

@UsagiElectric

3 жыл бұрын

I do really want to build another audio amplifier one of these days soon! Though, I think I may go in a slightly different direction. I do like the idea of using a bit more voltage for it, perhaps 80V or 100V, but I also want to see if I can get an Output Transformer Less (OTL) design working. It may not sound great, but it'll be a fun experiment!

Hermano es posible me pueda compartir el diagrama

@UsagiElectric

3 жыл бұрын

Hello! I believe you're asking for the schematic, correct? Here's the finalized schematic I used: i.postimg.cc/L5f6j0SW/002.jpg Let me know if you have any other questions!

That's a low quality audio pre-amp, I bet if you ever saw what a true high-fi audio tube amp looks like, you'd blow a gasket. Just kidding, I fully enjoyed this two part series. Instead of VU meter how about vfd's? I cant wait to see your other videos like these. Good job.

@UsagiElectric

3 жыл бұрын

Thank you! My grandfather actually bought a Magnavox Concert Grand new in 1962, which we still have and I recently got going. It's one of the most amazing sounding stereos/amplifiers I've ever heard. There are two amplifiers, and each amp has a treble and bass channel. The treble channel uses a 12AX7 amplifier and two 6V6GTs as drivers. The bass channel again uses a 12AX7 amplifier, but uses six 6V6GTs as drivers! That's a total of 16x 6V6GTs driving speakers! It makes a glorious sound, haha. Here's a brief video of it playing some Dave Brubeck: i.imgur.com/fbyFhhO.mp4

@paulawillaminachandler-ren3725

3 жыл бұрын

@@UsagiElectric :)

You could always fill that gouge with epoxy and then sand that back.

Tube amps can be powered at very low voltage, like under 6V...Hack A Day has shown this...very Interesting

@UsagiElectric

2 жыл бұрын

Thank you! And yup, tubes are really, really capable at low voltages! But, at the end of the day, power is still power, so if we want more volume/power, we gotta bump the voltage up.

Dude you made a headphone amp. Add a headphone port!

nice hair!

The "one-two" tubes are actually read as "twelve". This was used to indicate the heater voltage that they nominally used.

@badenmelhuish3215

6 ай бұрын

Yes, that right. Took me some time to work out what valves... er tubes you were using. Cheers.

The Champ topology has seen all sorts of creative implementations, this has to be one of the prettiest I've seen. Not implementing stereo is an interesting design choice, a dual gang pot should cost about a dollar from a supplier, or from just about any bit of audio hardware you'd break down for parts made in the last 50 years. But hey, if it looks good n sounds good. I'd never build an electric rabbit from tubes, so I'm happy to disagree. Different people n different ideas is often what makes the world a better n more beautiful place.

Why is 36 volts a weird voltage? Answer - historical memory! This was the lowest voltage proven to kill a human with a 50% chance.

@badenmelhuish3215

6 ай бұрын

That's shocking!!!

The drivers that you're using are small enough that they can't physically reproduce anything except very high frequency and the high frequency sound can't move much air since it has so little power. You could hook the output to a small hi fi speaker and it would be capable of much higher sound pressure levels and it would sound much better because the original source music contains low frequency information that is completely missing. You won't her a bass or drums at all even though they were there in the original music. All you're hearing of your jazz quartet is the high notes on the piano and the cymbals everything else is AWOL.

Sorry to have to give negative feedback (no i'm kidding i'm into electronic so will never be sorry for that) but you missed a big opportunity here. Two of the tubes should have been the ears of a bunny and those speaker should have been the bunny's eyes !!!

@UsagiElectric

2 жыл бұрын

Haha, you're in luck, check out this little guy I made: kzread.info/dash/bejne/ppqM27OCg9e1j8o.html Not quite the same, but close!

Sounds just like the radio, a tube radio, at the house of my grandmother.

I thought I recognized Chrono Trigger. New games suck. Half the reason for that is no good soundtracks and too much ambience. Music is a very powerful tool to elevate an experience, and is sadly the most commonly overlooked. Look at Jaws. Spielberg himself said that music score was 40% the success of Jaws.

@UsagiElectric

3 жыл бұрын

I'm right there with you! The soundtrack is one of the most pivotal parts of a game. There are a few new-ish games out there that have phenomenal soundtracks that absolutely make the game better. I would say that Doom 2016 and Doom Eternal are the best FPSs ever made because the gameplay and Mick Gordon's soundtrack feel completely in sync. Also, Darren Korb has made some fantastic soundtracks for Supergiant games, notably Bastion and Transistor. Ben Prunty also knocked it completely out of the park with FTL, which was definitely one of the reason I put quite a few hours into that game too. It's also not often that a movie has a soundtrack that feels like it's completely in sync, but I think that's what makes Christopher Nolan's movies such masterpieces. Hans Zimmer is absolutely brilliant and the Dark Knight trilogy, Inception and Interstellar simply wouldn't be the experiences they are without the awesome soundtracks!

Cool video. Dreadful music.

소리가 너무 작아요 ㅎㅎㅎ!!!