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Quote by kurtlives91
What a productive day, I got so much done. This morning I went to Home Depot and got hardware for mounting the power socket, tubes etc...Then I went to Canadian Tire and got some new tips for my soldering iron, some 60/40 Kester solder, some green neon spray paint for a custom Tube Screamer and a big ol storage box. Hope fully it can keep my bench a bit neater...

The sweet organizer box...Ya I got a lot of room in there for stuff. Only $14 what a deal!


The safety resistor....those filter caps can kill. (1M 5W)


Did some work on the chassis....Got the pots wired up partly. I also got the input jacks fully wired. They were a pain to wire vertically like that. Also the shielded wire was a pain, oh well its over. I also did some work on the power socket. The input power is called B+ right? I used 22 guage solid wire for the input power is this enough?


Here you can see the front of the chassis where the main controls are. You can clearly see here how I added a mid pot. Originally the pot furthest on the left was a input jack. I used this hole for an extra pot. I relocated the other jack below the original jack. High and low inputs makes sense.


Got the eyelet all wired up...Twas really fun. I think its pretty clean. Yes...no?




So basically that's all I can do for now. I just ordered some resistors and wire that I needed. Oh and some power tube sockets. The ones I originally bought were a bit small and I didn't really like them. Once I get one or two more resistors on the eyelet I can solder the "flapping" wires to their respectable pots/tubes. Then I need to save up for tubes and transformers...In conclusion building amps is MAD fun!!


That's a damn good price for that storage cabinet! Home Depot, you say? Have to go there one of these days.

That resistor will be able to handle over a 2000 volt discharge... I think you're safe

Your chassis looks good so far. Looks like you wired the fuse holder like I suggested. 22 AWG should be fine for B+, as long as the insulation is rated above the voltage you are using. 600V is the most common.

Looks good, pretty clean, nice job! Fun is right, damnit!
Sounds like a damaged component, but not easily determined without a function generator and oscilloscope, sorry ; -(
It's because of the way tubes amplify frequencies. Digital emulation comes close, but hasn't nailed it yet. Solid state over drive and clipping sound much different than tube over drive and clipping because they are completely different devices that don't work the same fundamentally.
Quote by kurtlives91
Right now...with out tubes, transformers and a head cab around $250.

Probbly when it is all said and done $400 - $500.


Sorry Hank just one...

Also with the fuse holder...does it matter which side I connect to the power socket. There are two leads I don't belive so but I just wanna be sure.


Hot goes to the end round lug.
Could be all 4 ohms in series, or 16 ohms in in parallel/series configuration.
I don't see why you're using a battery at all. The piezo circuit is passive, meaning it requires no power.
I wouldn't use 100K for the gain. I'd get rid of the two fixed 1 megs and use only the 1 meg pot.

I don't think I'm looking at the circuit you're referring to. I don't see a tone pot at all.

Increasing the value of any of the filter caps would assist in reducing hum. A choke would help as well. You might even want to think about using regulator tubes or zener diodes for voltage regulation. I would use a voltage regulator for the filaments, too.

Here's a nice site with equations regarding gain and frequency response: http://www.aikenamps.com/Equations.htm

Edit: Here's some more stuff from ax84: http://www.ax84.com/index.php/legacyprojects.html?pg=legacyprojects&project=p1&file=/media/ax84_m35.pdf
Yes, VERY noisy! I'm messing with some EL wire with one of my amps, and having an awful time getting rid of the inverter noise! So far, I have the inverter installed separately in a cast aluminum box that's grounded, and can still hear it.

Edit: Since you want the LEDs near the tubes, and the heater power is right there, not much extra wire, if any would be required.
Here's a kit: http://www.kitsusa.net/phpstore/html/MK-103-SOUND-TO-LIGHT-UNIT-KITsolder-version.html

Instead of mounting the LEDs to the board, you could run wires from the board to the LEDs.

You could maybe also use an op amp circuit to power LEDs instead of a speaker, if you connect it to your pickup output.

http://web.mit.edu/6.s28/www/schematics/lm386.htm
Sounds like a fantastic experiment! Let us know how it sounds. And you're right about the ohm rating.
I'm kind of at a loss with understanding what you want. Is there any way you can convey your ideas in a different manner? A simple list might work. Sorry if I'm being simple-minded, but maybe a list of your goals would help.
Hah, you guys. Skin resistance and the available current are the only things that matter when death is on the line. Simple Ohm's law pertains to all things electrical, even death by electrocution. I've been shocked by a 600 volt, 150mA secondary hand to hand... that one felt pretty mean. I'm probably lucky to be alive.

I work with 5000 volt DC circuits almost every day, but they're limited to 500 uA... hardly enough to kill you, but enough to remind you why people don't regularly walk around with high voltages strapped to their bodies.

I've also been shocked with 480, 240, and 120 volts with tens if not hundreds of possible amps behind them. The circuit could be limited to an amazing amount of current, but if your skin resistance is high, it will require a higher voltage to push the fatal amount of current through your body. On the other hand, if you have low skin resistance, it will require less voltage to push enough current through your body to kill you. Ever hear of the poor bastard who died from a 9 volt battery in the bathtub? I've heard stories, but nothing I was able to prove.

If the current is limited, you can receive all kinds of voltage without much harm. High voltage, however, can burn, which is a hazard itself.

The biggest danger of tube amps are high voltage capacitors, which can unleash a crapload of current in a very small amount of time at a formidable voltage. Hence the warnings.

Sorry for hijacking the thread. As far as building an amp, motor-coordination-wise, it really isn't any more difficult than assembling a model car. You just have to pay attention to the nuances of the beast; just like assembling a model. That goes for copying a circuit or building a kit. Designing a circuit, on the other hand, requires a bit more thought and expertise.

So, after all that useless information, my advise is to use Google to search for what you need. I'll be nice and give you a link: http://www.tubedepot.com/
I enjoy your posts, just not much to say at the moment. Although, I do like the mica caps. Many people overlook mica for some reason. I had to chuckle at your "big elecro cap" comments. Big to me is several farads at several hundred volts. I'm sure there are bigger, but a cap that fits in your hand isn't big, hehe.

Almost sounds like you need to order from a different supplier if your parts haven't arrived yet. How the hell long does shipping take, anyway?
Small amps and effects can be built into almost anything. Sometimes perf boards just get in the way
Yeah, colored LEDs would work the same. Connect the resistor to one of the LED leads first, then connect the other LED lead and the free lead of the resistor to power.

By underneath, I mean I glued the LED to the center of the tube socket, underneath the tube. Play around with the positioning.
I would exchange both the first 220K feedback resistor as well as the second 120K feedback resistors for pots, to begin with. That will allow you a huge amount of gain adjustment. Also, try swapping the 1N4148 diodes for germaniums (1N34, etc.) and/or, place the clipping diodes in parallel with the first, second, or both feedback resistor stages (tube-screamer-ish). Two successive stages of feedback clipping sound sweet, IMO.
You mean like this?

I'm using ultraviolet LEDs under the tubes. You can connect LEDs to your tubes' heater power. If the heater circuit is AC, you don't have to worry about the LED polarity. Just make sure you use the correct resistor for the voltage. About a 470 ohm resistor for each LED will work for a 6.3 volt heater supply.

Wikipedia on LEDs: http://en.wikipedia.org/wiki/Light-emitting_diode

As far as wiring, all you do is connect a resistor in series with the LED, then connect the LED across the heater power supply.

It would help if you let us know what brand and model amp you're planning on modding.
I looked at your piezo circuit. It's not going to do much of anything. What exactly are you trying to accomplish?
... And look at other electronics suppliers online, like allelectronics, electronic goldmine, parts express, newark, jameco, mouser, mcm, digi-key, herbach and rademan, alltronics, etc.
Tool already did that for the Undertow album. That's like so last millennium! Must have been fun, though.
Do you have a link to the schematic? Thanks.
Look at the Seymour Duncan wiring diagram page: http://www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=2h_2v_2t_3w



There's a little picture in the lower left-hand corner that shows you how to connect the single conductor.
What I actually meant was, would anyone buy a portable tube amp, and spend more money on it, or settle for the current solid state completely portable amps such as Pignose? Would anyone want a truly portable (camping in the woods) tube amp, or just buy a nice solid state they could play through?
^Cool, thanks man. I love experimentation.
Nice job for your first time! I hope you had fun and learned a few things as well. Building amps, as well as just playing with electronics, can become addictive.
I love your setup man! It's almost as messy and random as mine. Also, it isn't a proper bench unless it's in the basement, right? :-)
I'm very curious about how those diodes sound. Find out as soon as you can. I'm kind of skeptical of it. And where did you get them, btw?
Dude, I don't mean to be a d!ck, but this question is asked very often. Please do us a favor and read the pedal building thread thoroughly: https://www.ultimate-guitar.com/forum/showthread.php?t=630592

I think that the components at the store you found would work just fine

Just a caveat: metal film resistors, and silver mica, polyester, and paper caps are better, but negligibly so in a pedal. Germanium sounds smoother than silicon.

If you aren't clear about something after reading for several hours, let us know.
Now they're catching on! I thought of using a small inverter with a sealed lead acid battery, but haven't tried it yet. The UPS is an inverter with a battery included.

So nobody has an opinion about whether or not completely portable tube amps would be attractive?
Sure! Or, buy a big PA and throw a party!
Not to speak for Someone, but the transistors you are using need their bases to be biased in order for the transistors to conduct. Connect one end of your 2 meg or so resistor to the base of the first transistor, and connect the other end to the supply rail. That should bias the transistor so it conducts appropriately and passes your signal. The base is the center pin.
If you can't move the speakers, there's really no point in using them. Use your Celestions, and use the Nippo-whatsits in a concert situation.
Here's a list of functions to get you started: http://sig.sapp.org/doc/examples/soundfile/

I don't do much audio programming, but I do a little testing programming using D/A and A/D converters, which is basically the same thing. Read all you can, do some searches, and good luck!
I think the schematic to which you alluded would work for a headphone output.

Do you mean you won't include the DC input jack for external power? If so, just copy the circuit as drawn in the schematic. You probably don't need the cap if you are just using a battery.

Yes, connect the end "on" terminal to B+. Connect the center terminal to your LED. Don't forget the LED resistor!

I think those boards are pretty small. I think a board would fit in the enclosure.

Your current speakers will work. Don't expect to be blown away by your tone, though.

Just use the cheap 1/4 watt carbon composition resistors. No need for anything special.

There are a lot of electronics distributors online. You should be able to find all the caps you need. You can adjust the values slightly without any ill effects. I use All Electronics quite a bit: http://www.allelectronics.com/cgi-bin/category/140/Capacitors.html

If your enclosure is metal, yes. If not, don't worry about it.

And please post pics. A picture is worth more than typed characters, lol.
... back to my inverter idea, ahem. If you want true portability in a tube amp, it would have to be battery powered, yeah? If you're going to use conventional tubes, you would be required to step the voltage up, which would require an inverter circuit. Basically, you change the DC to AC with an oscillator, then step up the voltage with a transformer.

If you have an oscillator, you can run it through something like a toroidal power transformer: http://www.hoffmanamps.com/MyStore/perlshop.cgi?ACTION=enter&thispage=parts1.htm&ORDER_ID=!ORDERID!

After that, you can have the conventional power supply and tube circuit. Doing it this way is rather inefficient, though, since every time you convert the power, some is lost as heat due to different types of energy resistance. Efficiency doesn't matter as much when you're plugged in to an outlet. It matters more if you're relying on a battery.

If you want to keep it all 12VDC, mess around with those space charge tubes. They don't get very loud, but some configurations sound pretty good. Plus, you don't have to worry about high voltages.

Just as an aside, does anyone here think that portable tube amps have a real world market? I mean, do they have an advantage over solid state portables in any way? Would anyone want or need a tube amp while camping?

Oh, and I'm sorry, WickedBeast, but I have to correct you. It's not a 9 volt cell, it's a 9 volt battery. Cells consist of one anode and one cathode. Batteries consist of two or more cells. Yes, I'm anal
Please post some pics. Don't make me beg Don't worry about the solid wire, as long as you don't nick it. Even if you do, it'll take a few bends back and forth to break it. It's going to be a great amp!
Of your choices, I have to say the power amp section, which would be the output tubes and output transformer together, since they comprise a system. All other things being equal in a listen test, I believe the tube power section will always sound better to the ear than a solid state output section(unless the output xformer sucks ass!) Regardless of preamp, speaker, cabinet, or rectifier; if you compare both with the same set up, the tube design will win.

The philosophy I've been developing lately, though, is more of a complete package solution, rather than which part is greater. I think our hearing is subjective, so we all like to hear different things. I think finding the right combination of components that pleases the one using it is most important.
Both schematics on that page are wrong. Try what Someone says.