There were tubes that were specifically designed for low voltage operation. They were very common in car radio's way back when. I have this same pre amp although I cheated and got mine assembled from eBay. The one real good thing about this circuit is that it allows me to connect my android phone my Hifi system so that I can record the music on my phone to tape, without it, all the levels have to be turned up but with it, it corrects the crappy headphone output on android phones... It was worth it for me. There's another pre amp that Dave over at EEVBlog did a video about and that one fed plus minus 12v to the tubes... I thought that it was strange that they could run on such low voltage but after I dug around on Google, I learned that it was a thing once apon a time and there's a good page that explains everything and also gives a list of all the tubes that were specifically designed for low voltage.. good job on the build.. the blue Led's kinda give the tubes that high powered mercury vapour rectifier tubes... Boy do those things look scary and beautiful at the same time LoL... I found a price list for Sylvania vacuum tubes from the 1930's, they had a water cooled tube for $500 back then, that's over $9000 today LoL, who the hell even had that sort of money back then? I couldn't afford $500 for a tube today let alone anything more than that LoL...
@arose460
6 жыл бұрын
With your help I built this little pre amp! I'm not sure I could have done it other wise. Thank you sir!
@12voltvids
6 жыл бұрын
arose460 Your welcome. These little kits can be fun to assemble and give a sense of accomplishment when finished.
@nor4277
6 жыл бұрын
That's why I like tube radios ,they sound better to me
@johnsmith-ld7fu
7 жыл бұрын
I built this amp, love it, just ordered another.
@darkside7786
3 жыл бұрын
Back to memory 60th 👍🏼😆 good job ❤️ next day I want to buy
@sivoltage
3 жыл бұрын
I jumped out of my skin when you got the spark when testing the voltage! hehe :)
@12voltvids
3 жыл бұрын
A little spark never hurt anyone.
@bassblaster505
7 жыл бұрын
I Actually have that same tube buffer with its case. i got it on eBay for $10 and i always wondered how they got +/-28V from a single 12V with no center tap. great vid as always mate
@12voltvids
7 жыл бұрын
Yup, the capacitor pumped voltage doubler. Gets the job done. First time I saw such a setup was the voltage pump used on some vacuum fluorescent display supplies. I serviced a technics tuner awhile back that had no display and it was one of the electrolytic caps in the voltage pump that shorted and killed the display.
@SciPunk215
7 жыл бұрын
As a complete amateur, I'm always curious about that. It seems like you're getting something from nothing, right? So obviously something's got to give. I guess that means less amps will flow, so in the end energy is conserved.
@12voltvids
7 жыл бұрын
Obviously a circuit like this is not going to work for a power amp. Tubes are voltage amplifiers not current amplifiers. So this type of circuit works fine for this application. Vacuum fluorscent display circuits quite often use the same type of circuit to pump the 40-60 volts required for a display tube. Since this is a preamp, we are talking only line level signals, and the current actually flowing through the tubes in in the micro-amp region.
@williamsquires3070
7 жыл бұрын
Here’s a wild idea; replace the 3mm blue LEDs with 3mm “flicker-flame” LEDs! :)
@12voltvids
6 жыл бұрын
Orange look good. Enhance the glow of the tubes. My little 2 watt ELEkit TU8100 has orange LED under the tubes and they look fantastic. Light the tube base up a little more and enhance the glow. I have this little amp in my bedroom, and listen to music on it at night in the dark, and it looks really nice. That one is only 2 watts per channel, which is more than enough to listen to at night. The sound quality is fantastic.
@rangerdoc1029
6 жыл бұрын
I kinda like UV in mine. Not too bright though. Just a very subtle hint of a glow.
@semajsemajsemaj99
Жыл бұрын
Oh nice ! It worked, have it too , great feeling. I have one more to put together 😁
@glenngoodale1709
5 жыл бұрын
One of your top videos ..... good teaching
@keithchua5840
3 жыл бұрын
I just bought this diy kit as well. What do you think will be a good component to upgrade? Any specific values?
@AlienRelics
5 жыл бұрын
Why is R16 attached to -28V? That will make a tremendous POP if it is plugged into an amp live, as it puts -28V on the output. It should be connected to ground. The transistors in the power supply are NOT regulators. They do not make the outputs equal in magnitude. They are hum cancellers.
@billkalina3089
4 жыл бұрын
I have ordered this kit. Looking forward to the build. One question, what value resistors to use for minimum gain?
@ws_stelzi79
7 жыл бұрын
I always use the color band decryption of resistors for colour blind people! I Stick the red probe of a multimeter on one end and the black probe on the other end and read out what the Ohmmeter shows. For me this is faster than messing arround whith colour bands. I'm not colour blind but have problems figuring out which colour one band is supposed to be.
@12voltvids
7 жыл бұрын
That works, but that is for lazy people. The only time it gets confusing is if the first color is brown, and the tolerance is also brown. If you are dealing with all 1% precision resistors then the presence of 2 brown can lead to mis reading is you are not careful. On normal 4 band resistors this is never a problem because most are 5% with a gold band for the tolerance. silver is it was a 10%. Once the color code is learned it is easy. I have to remember 2 different color codes. Resistor / capacitor codes and wire codes for 25 pair telecom wiring. It uses the same 10 colors but they mean totally different things. Tip colors White red black yellow violet. Ring colors Blue Orange, Green Brown slate (grey). Sorry multimeter won't work for that. If you are color blind, you can't have my job, and screaming discrimination based on disability will get you nowhere. Normal color vision is a requirement of my job.
@neccron9956
6 жыл бұрын
Some of these kits do not have the best grade of parts, so I always verify the components first.
@12voltvids
6 жыл бұрын
Gustave Green Meter always works for sure. Since I know the color code I use my eyes first and if any question I reach for the meter.
@paweldun
6 жыл бұрын
i love this kits. i use to start from the center to the sides soldering parts.
@kyoudaiken
7 жыл бұрын
The thing is digital equipment has the best fidelity you can get, and the guys in the studio mastering the sound still optimize the music to sound good on crappy phone speakers or crappy iPhone ear pods or for FM radio transmission. You just add a little bit of softness and distortion to the sound, making it technically worst fidelity but practically sound warmer and nicer. Digital equipment plays the audio back as is. 100% fidelity (when lossless).
@12voltvids
7 жыл бұрын
Digital recording is the best you can get, period. No compression PCM sound, such as a CD or DAT tape, or better still SACD recorded at 96KHz 24 bit is flawless. Losless compression such as FLAC also gives prestine sound, and a good solid state amp, and speakers can reproduce this exactly as the microphones picked up the sound. Analog storage formats such as tape, and a groove carved in a record have severe limitations due to them being a mechanical, or magnetic analog medium. As to recording studio's the biggest problem during the initial CD release is that recording studios were producing for the formats of the day. Vinyl and Cassette. Because of the limited dynamic range of these formats, around 50dB, sound was compressed and EQ for those formats. In the pop rock arena, there was rarely, if ever a new digital mix made for the CD release. Most CDs in the 80's and 90's were all AAD. Analog studio tape, analog stereo mix, digital copy. Even when CD took over, many studios were still using analog multi track, but mixing to DAT. These were the ADD recordings, and featured a slight improvement in the mix, but they were still sourced from analog tape. When full digital recording because the standard there was a tremendous improvment in sound, if the engineer knew how to mix. Lables such as GRP, Blue Note, Telarc ect did record and mix right, and their quality if unbelievable. I have a copy of Mountain Dance by Dave Grusin on CD and that is as close to perfect as you will ever find. He took the best session musicians in the business, Phil Spectors wall of sound caliber from the wrecking crew days, took them into the studio, and recorded the album "hot" as they say. Played live, and recorded direct to a 2 channel hot mix. The dynamics on that CD are incredible. There are many CDs that were cut that way, mostly Jazz recordings. Now here is the kicker though, the human ear is NOT perfect. It fact it is far from perfect. Just the way a tube processes sound, it adds slight colorization to the sound and removes the sterility of sound. No matter how good your recording, when playing through a tube buffer some of the warmth is returned. I have both solid state and tube gear. I have built a couple of class A tube amps. One is a rally low power amp, and no it is not going to rattle any windows, and I use it for quiet listening, but I tell you the presence is incredible. I was listening to Kitaro though it on some really cheap speakers, playing from an MP3 player I might add, and I could pick out the electric guitar and electric violin among the synthesizers, and the drums. I have heard this track many times before and it never sounded as good as when I listened through a tube amp. This is the reason that tube gear is still around, and why people pay astronomical amounts for it. You may disagree, but companies like McIntosh stay in business selling amps for thousands to people that perfer the sound of tube amps.
@multishit6664
5 жыл бұрын
LOL. Analog has no sample rate.
@chrisbeard7940
5 жыл бұрын
I got shocked by 48vdc when splicing a phoneline with my sweaty arms wrapped around a heating duct...was quite surprised and learned a lesson. :)
@frankgeeraerts6243
4 жыл бұрын
Penthode tube ....similar to EF95 and 6AK5 and some other types... You can also use the higher quality Western electric tube...WE 403A ( very good sounding ) , good tubes cost sometimes more than the price of the kit.. Some tubes were especially developed for low voltage on the plates ......used in planes ( WW2....12SX7 on the 36 volt generators in the B17 flying fortress ) and also for car audio on 12 volt batteries and other applications. .
@proffessasvids
3 жыл бұрын
Those western electric 6ak5 are mega expensive now. Thin on the ground. Lovely tubes though. I'm running mullard m8100 atm xx
@elsaarmstrong-zp6ng
Жыл бұрын
You need to insulate your probes right down to the points and sharpen up the points, ! You shorted one while checking voltage near the video end! I have done shorts as well so heat shrink the probes and sharpen the points- less chance of slips and damage! Very good videos though! Well done!
@12voltvids
Жыл бұрын
Didn't short. Camera angle might look that way but i didn't.
@gizmothewytchdoktor1049
6 жыл бұрын
Triodes at Low Voltages Linear amplifiers under starved conditions. very interesting read and function explanation for these type buffer units.
@dharmakissoon
6 жыл бұрын
thanks you've been a big help . is there a way to supe up the tube buffer like more caps ,use aluminum resistor more tube ?
@standishgeezer
7 жыл бұрын
Now look what you did....I've had to go and buy one :-)
@12voltvids
7 жыл бұрын
Its a cool little kit, and it sounds great.
@mpachinko4069
4 жыл бұрын
Thank you for this vid. I have one of these and frankly it scares me. You video helped clear up some of my fears. I do have one question. Are these safe for the receiver? Can they be safely be plugged between say a laptop and my main receiver?
@12voltvids
4 жыл бұрын
Absolutely. That is what they are designed for. To go between your source and amplifier to add even order harmonics for the tube sound. No high voltages are present on the inputs or outputs. The DC is blocked by the capacitors.
@ICStation2013
7 жыл бұрын
Wow, wonderful video project appears once again~~~^0^ Thanks so much.
@Aris-wz4kq
5 жыл бұрын
i bought this circuit . I think it is good . Do you have a suggestion for an A class transistor small amplifier to plug it?? A diy small (3-4 watts) will be nice for me
@cmj20002
6 жыл бұрын
I use my component tester on all of the resistors so I don't make a mistake reading them and also I test the components before I install them, that way I know they are good. I have a kit that looks the same only the large traces are covered instead of being exposed.
@12voltvids
6 жыл бұрын
Well if you knew your color codes then you wouldn't make a mistake reading them.
@moodesigner
3 жыл бұрын
The actual trick here is that the audio op amp is built into that 50k potentiometer, thats where actual amplification happens, and those cheap tubes are used as a buffer.
@elsaarmstrong-zp6ng
Жыл бұрын
If you got a small output transformer could it drive small speakers say 2-3watts?
@danielauen7790
3 жыл бұрын
I have a transformer that puts out 16v ac with no load, and no center tap, How bad of an idea would it be to use it with this kit?
@davidgriffin79
6 жыл бұрын
As much as I like your channel, and in some ways you're inspiring me to get back into electronics, I don't agree with the "digital electronics add a harshness to sound" more like analogue recordings have a mellifluous warmth and rounded sound that we, of the older generation, have become accustomed to. This product is equivalent to a DAW analogue sound plugin. I agree with most of your reply to Kyôdai Ken. I remember the first time I saw digital TV in the late 90's: it looked too clean, I thought it needed a little noise to make it "comfortable watching". Now, when I see even a good analogue video recording, albeit digitised for KZitem or broadcast, the noise is obvious and it looks very dated, like an old movie. I've seen TV shows which were shot on film and, in later series shot using digital video cameras; invariably the digital video looks cleaner, as if a veil has been removed, which, in a way, it has. We have moved forward in both video and audio. In audio, with good quality equipment (professional DAC, headphone amp and headphones, say ) it's now possible to hear exactly what the mastering engineer intended, good or bad.
@PeterMilanovski
4 жыл бұрын
I think that what you are missing is that audio is and was always ahead of video technology, in the 1940's they had 2.5KW vacuum tubes that were water cooled, as time passed the vacuum tube amplifier designs got better to a point where there was no need to improve on the design anymore. I like the fact that a 10W tube amplifier has enough power to fill a house but with today's D Class amplifiers, all you see is thousands of watts of cold colourless sound.. I prefer tape over CD except when I run a CD through Dolby C noise reduction and then it comes alive.. Even MP3 sounds better through Dolby C noise reduction... Old school noise shaping... But on a whole, the difference between vacuum tube sound Vs solid state vs digital is minimal compared to old TV and video Vs new tv and video... If audio didn't progress further than vacuum tubes, you wouldn't complain because there's nothing wrong with the sound, but then again, I just remembered that I watched a movie on VHS not that long ago, it looked bad until I got into the movie and I totally forgot about the quality... Yeah I don't know... It's all good (except class D amps).
@Hrostbjergsorensen
6 жыл бұрын
hallo nice video. can you help a bit. i have the same tube preamp kit and iam finish with the build. but i have a transformer 230vac to 15.5 vac 10 VA . can i use that without any problems? or is the to high voltages?
@oldradioguy65
7 жыл бұрын
Sounds Awesome!
@airmicrobe
2 жыл бұрын
Thank you for the video
@millercroger
6 жыл бұрын
The 6J1 is actually a pentode. They are using it as a triode.
@12voltvids
6 жыл бұрын
If it was an old RCA 6J1 then yes it would be a pentode, but this uses the Chinese numbering system, and in this case it is a triode. Confused yet? If you look up your 6J1 you will see it is an octal base, but as you can see this is a miniature.
@millercroger
6 жыл бұрын
There could be no American 6J1 because the 1 would would signify only one active element in the tube. The Chinese 6J1 is indeed a pentode and the American direct sub is 6AK5. The 5 indicating five active elements making it a pentode. A correct drawing of the Chinese 6J1 can be found online. It is not represented correctly on your schematic.
@gabrielnemeth5311
4 жыл бұрын
Will this match the impedance to Phono cartridges and make a good phono pre-amp ?
@tenmillionvolts
4 жыл бұрын
No. It's for line level. Phono cartridges have a very low output so they need extra amplification. Also, they need special equalisation (look up RIAA curve). You need to put it through a phono preamp and then a valve amp like this one
@elsaarmstrong-zp6ng
10 ай бұрын
How much did the kit cost online? Fraser
@standishgeezer
6 жыл бұрын
Having got one of these, the slight issue is trying to get an AC/AC power supply that delivers 12V AC in the UK. The UK supply is supposed to be 230V but is, in fact, normally anything between 242V and 250V. This means that the power supply output is higher than 12VAC. I got a 240V-12VAC power supply from a very reputable UK component supplier which , unloaded, measures 15.4VAC (TRMS). Although the unit works (having only run it for brief periods), I'm concerned that the delivered, recfified filament voltage will exceed the 6.3VDC absolute maximum specified for these tubes.
@12voltvids
6 жыл бұрын
Just change the value of the current limiting resistor in the filament circuit. This is the large 2 watt 2.2 ohm resistor. Go up to a 3.3 or 4.7 and that will drop the current and voltage to the filaments. I have tried other tubes in this, and I had to eliminate this resistor entirely as the tubes I put in to test required more power then these ones for the filaments. Tubes can withstand a little over voltage anyway. They can withstand a nuclear blast! EMP that would kill all solid state devices has no effect on tubes at all.
@markanderson350
6 жыл бұрын
how true! you can red plate for a few minutes too, solid state would POP! 10% over would maybe shorten the life a few years. hard to say. great job!
@PeterMilanovski
4 жыл бұрын
@@12voltvids what other tubes have you tried in this circuit and did you notice anything that you can say that they sounded better than the 6j1 that came with the kit...
@Aris-wz4kq
5 жыл бұрын
Thanks for this nice video. Is this an A class or AB or something ? Do you know??
@GeorgeGeorge-xj2bc
4 жыл бұрын
If the amplification of the signal on each channel is done using only one active component then for sure it is class A. It is preamplifier and amplifies the signal's voltage feeding high impedance input.
@elsaarmstrong-zp6ng
10 ай бұрын
Could headphones be driven on output without matching transformer? Fraser
@Aris-wz4kq
5 жыл бұрын
replacing some components and using a higher voltage transformer would this be useful ???
@DAVIDGREGORYKERR
7 жыл бұрын
A KORG(R) Nutube 6P1 could be used in a situation like this but use dual in line sockets, the Micro vacuum tube with the wire ends from the CCCP might be usable here and should run on a lower voltage.
@akagaminoshanks4831
3 жыл бұрын
My tube amplifier has no sound, I will give DC current, what is damaged please help
@Thephotonguy
6 жыл бұрын
If I want to add a gain potentiometer I would put it in place of the cathode resistor? Also what should the value be if I want it to distort like a guitar am?
@836dmar
4 жыл бұрын
It doesn’t appear the LEDs are used in biasing the tubes. Are they required in the power supply or can they just be omitted?
@Steve_Blue_Oyster_Cult
Жыл бұрын
Omit them as they do nothing but are just for looks. That's what I did to mine,
@elsaarmstrong-zp6ng
10 ай бұрын
Would a linear psu not be better than smpsu I.e. low noise with linear? Sounds pretty good thoiu
@12voltvids
10 ай бұрын
Smps operate in the 60 to 80khz range. No you won't hear any difference.
@moodyga40
6 жыл бұрын
nice pre the tube is a sharp cutoff pentode 6au6 will work well in this circuit and a GE 5654
@saltyjonny1
4 жыл бұрын
Thanks pal followed u step by step and was doing an orsem job thanks to yr orsemness and then I put the on of switch on wrong side of the circuit board and then fk it all up trying to get it of??? Why ho why fk only now's ..can u tell me if it matters if u don't put the wire bit at the front of the two yellow one at the front as you did as it would look neater .Thanks yr orsemness
@elsaarmstrong-zp6ng
Жыл бұрын
Could this unit be used as a driver for a solid state power amp? Just to get the valve sound?
@12voltvids
Жыл бұрын
Sure can.
@Aris-wz4kq
5 жыл бұрын
if you apply a bigger transformer , would it be better??
@waynegram8907
3 жыл бұрын
what are the differences between Long Plate tubes compared to normal plate tubes, they say tubes that are the same tube number but have options called "long plate". I'm not sure what are the benefits of using long plate tubes compared to the normal plate tubes. 12AX7 has a long plate tube version but not sure what it can do differently.
@12voltvids
3 жыл бұрын
They have a different sound. If you compare them you will hear a difference. One is not better than the other just different .
@waynegram8907
3 жыл бұрын
@@12voltvids yes I know, but the long plate is able to do what differently? the long plate can have more plate voltage or more electrons output plate current?
@rayprevailer8454
3 жыл бұрын
I hate that about resistors. There should be some easy to see designation on which way to read them. I always use my meter when in question. I have also been a telecom guy for several telecoms. Watch out for ring voltage and circuit voltage from T1's. Fantastic video, thank you.
@JMNTN
4 жыл бұрын
my kit came with sanyo capasitors however i think they might be quite old because one of them is swelling already
@tenmillionvolts
4 жыл бұрын
They are fake Sanyo caps. They are cheap Chinese ones that have been branded Sanyo. The cheap kits are full of them. Buy some better caps locally and replace them with good brands
@mitch19636
7 жыл бұрын
Hi, mate thanks for the interesting vid. I love the Idea of playing with Electronics of the past :) I am sure some people would find the even harmonic distortion more pleasant than odd harmonic distortion that solid state gives... It would have to, of course, have a tube power amp as the odd and the even harmonics might beat and negate the interesting Idea of a tube pre-amp. Once again thanks mate. Mitchell.... VK2XMM.
@12voltvids
7 жыл бұрын
Mitchell McCreath You don't need a tube power amp. The buffer does the trick. I have both. A single ended tube amp sounds very smooth indeed but just adding a tube to the preamp makes a difference. Most solid state amps have very little distortion at all so adding a bit of even order harmonics warms the sound up nicely.
@mitch19636
7 жыл бұрын
My receiver has about 0.0022% at 180watts. Good look to anyone hearing that. :) Even my guitar effects pedal has a 12AX7 in it for even harmonic distortion effect. Of course, they have it showing through a window so you can see her light up.
@12voltvids
7 жыл бұрын
The reason that these little buffers are becoming so popular is to soften up digital music, especially MP3. Add some even harmonics to take the edge off harsh digital compression artifacts and warm the sound up. They really work. Luxman was doing it back in the early 80s with their LV series hybrid amps. Now we are getting these units that operate on lower voltage to accomplish the same thing.
@kitz8127
7 жыл бұрын
Interestingly nice project. How much did it cost you and where did you get it?
@kitz8127
7 жыл бұрын
Ok, got it!
@12voltvids
7 жыл бұрын
Well mine cost me nothing, it was a promo build from IC station.com. They send me things to demo / build, and I get paid from advertising revenue the video attracts, and they get a demo video out of it. I think it is something like 11.00, fairly inexpensive considering what it is, and how good it sounds.
@kitz8127
7 жыл бұрын
Thanks, saw the youtube link in the video.
@subcityofficial9409
4 жыл бұрын
Would love to know what resistors you would use to get some distortion/saturation out of it (only changing resistors)? I want to put it between my guitar pedals and have drive it to distort.
@12voltvids
4 жыл бұрын
Oh it will distort if you drive it hard enough.
@subcityofficial9409
4 жыл бұрын
Thanks for your reply. Keep up the good work!
@vonfefer
6 жыл бұрын
Hi, I have one just like yours but when I turn the volume up, the sound distorts and become like an exploded sound (like its chopped or something). Can you tell me whats wrong? Also the sound is too low... Thanks.
@vask9254
5 жыл бұрын
I think you should use a more powerful 12V/DC power supply . A 12VDC with about 1.5A to 2A output will do the trick. To me it sounds like the board does not take enough juice when the volume is turned up.
@janjanski6884
6 жыл бұрын
Good skills...😁
@williamsquires3070
7 жыл бұрын
For me, any resistors = excuse to get out the auto-ranging DMM!
@aryonllewellyn
7 жыл бұрын
Nice Project and great valve sound. Can you please give me the name of the tune you played and the artist? Thanks.
@12voltvids
7 жыл бұрын
The composer is Jack Waldenmeier, and his company is musicbakery.com This is royalty free content. The track I played is called "Corporate Image" I can't recommend musicbakery high enough for quality music that you can license for your projects. Yes the tracks are quite pricey if you buy them separately. I have had this music for years since I was in the commercial video production business. We had to use it for videos that were sent for duplication or broadcast.
@rafaeltoschichiafarelli8952
6 жыл бұрын
hey dude, is there a test that you can do to measure the quality? somehting like inserting a known signal and measuring the output?
@12voltvids
6 жыл бұрын
This is just a basic triode. The output will equal the input. What gets added is the even order harmonics. There is no test equipment that can measure this, except for perhaps a distortion meter, which will show more distortion on the output than the input, however the human ear does not hear even order harmonics the way it hears odd order harmonics, which is what we refer to as harmonic distortion because even in very small amounts it sounds very harsh. Even order harmonics on the other hand enhances the sound, and only hearing it will convince you. There is nothing I can show, or anyone for that matter over youtube to show how a tube changes the sound in the most pleasing way possible other than to describe it as a more full, natural sound. You have to experience it first hand, but once you do you will know why audiophiles pay the money they do for old school vacuum tube amps, and why there are manufactures still making them. I own 4 tube amps 1 vintage, 1 modern, and 2 I hand built. The 2 low power (2W and 9W per channel respectively) are the best sounding amps I own. My phono preamp is a tube preamp too. A tube buffer like I built here adds many of the benefits of tube sound to solid state amplifiers, and makes them a hybrid amplifier, which adds the benefits of the even order harmonics, but still has the clean high power sound of the solid state amp. A full single ended tube amp is still better, but this gives most of the sonic benefits.
@rafaeltoschichiafarelli8952
6 жыл бұрын
cool! thanks for the quick reply! I was wondering about the frequency response, but you answered it! keep it up!
@12voltvids
6 жыл бұрын
A triode has literally an infinite frequency response. There is nothing to limit it in a tube.
@rajeevmathur2264
6 жыл бұрын
Can we use this kit as a phono amp for a turntable with MM cartridge??
@joedirt5965
6 жыл бұрын
I like the video. So I ordered one from IC Station took 3 weeks to get and was missing part to Finnish the amp. Missing capacitors!
@12voltvids
6 жыл бұрын
Contact them, They will find you the missing parts.
@joedirt5965
6 жыл бұрын
12voltvids they contacted me today and said they will ship the missing parts
@12voltvids
6 жыл бұрын
I let them know that one of the tubes in my hybrid amp kit failed after a few days and they sent me a complete replacement kit that I have yet to build.
@PeterMilanovski
4 жыл бұрын
@@12voltvids The 6J1 Tubes are $1AU on eBay, they are literally the cheapest tubes that you can buy.. good value.
@aceofspades1217
6 жыл бұрын
So can I use a 1A wall wart. What exactly is a 12V AC converter I couldn't find that on ebay.
@12voltvids
6 жыл бұрын
Adrian Oliva It needs to be an ac output not a DC output. 12 volts AC at 1 amp. Most adapters are ac to DC adapters. You need an ac transformer. A transformer just changed the voltage but does not convert it to DC. You should be able to find an ac adapter with an ac output like I used easily as many products do use an ac input. As they have their own rectification and regulation in the device. This is why this needs AC. Because it uses a voltage doubler to make the higher voltage that the tubes require to operate.
@cmj20002
6 жыл бұрын
I used color changing LED's in mine for a little flair.
@TONY-gj3jl
6 жыл бұрын
Power in ac 12v?? No tap 12-0-12?? Ciao dall'Italia
@zx8401ztv
7 жыл бұрын
Thats a really nice kit :-D, i think i would put red leds in, and lower the brightness, they are just too bright. I know im old fashoned but i do like through hole components better, smd just doesnt appeal to me. I know smd have there place, like computers and phones, but they are no fun to work on :-(
@12voltvids
7 жыл бұрын
Orange LEDs look nice. My TU8100 2 watt tube amp has orange LED under the tubes and they look good. I have no idea why everyone uses blue. Blue looks ok on nixie tubes but not on audio tube applications.
@keithchua5840
3 жыл бұрын
@@12voltvids Any idea whats type of orange led can be use instead of these blue ones? I may wanna order this kit and put orange leds before i solder in the tube sockets
@12voltvids
3 жыл бұрын
@@keithchua5840 orange led are readily available.
@keithchua5840
3 жыл бұрын
@@12voltvids Any specific wattage led you'll recommend?
@12voltvids
3 жыл бұрын
@@keithchua5840 no just standard led. They are not measured in watts like lighting LEDs. Just panel indicators.
@DJ_Joe_DC
5 жыл бұрын
hi there, so which side is positive on the board where the 35v capacitors go please? the side of the circle with lines or the side without?
@12voltvids
5 жыл бұрын
Shaded side negative
@DJ_Joe_DC
5 жыл бұрын
@@12voltvids thanks dude, so I take it that's a "rule of thumb" on all PCB'S....I'M just starting out with these types of projects but previous things I've done (namely RAKIT synths and sequencer) the instructions are easier to follow so I thought I'd ask a professional....
@12voltvids
4 жыл бұрын
@Mark Jherick Sevillejo If you want but the new ones included should be fine.
@larryshaver3568
6 жыл бұрын
when in doubt grab your meter is a great rule
@joicejewerly5579
2 жыл бұрын
You have a very funny friend😂 Ha ha
@12voltvids
2 жыл бұрын
Funny as in ha ha or just "funny" lol
@R1D9M8B4
2 жыл бұрын
Lolz.. imma ser if I can add this thing to my car audio set up. This will be entertaining
@tomassafran4001
Жыл бұрын
16V AC. yes ok?
@madmax2010ok
5 жыл бұрын
I got the same preamp (buffer) kit on Ebay from another supplier. Mine came with carbon comp. resistors and ceramics for the coupling caps (the 1uf ones). It hums and does not sound great. Is it the parts....or tubes...or ??? Starting to think I should chuck it in the pile.
@iblesbosuok
5 жыл бұрын
Try to replace all 470uF/35V electrolytic capacitors. Hum is mark there are bad electrolytic capacitors.
@moretti740
5 жыл бұрын
I think this is a slightly modified clone of the Musical Fidelity X-10D Tube buffer
@12voltvids
5 жыл бұрын
Tube buffers are pretty simple devices. A simple triode so all designs will be very similar.
@larryshaver3568
2 жыл бұрын
please disregard the below statement, i just realized precision resistors are different
@12voltvids
2 жыл бұрын
That's right.
@4stringsTAO
6 жыл бұрын
Hi, I followed this video carefully to be able to mount the same kit I purchased. But when I put it into operation, the right channel has a higher volume than the left channel. What could it be? (I state that I powered it with a 9VAC because I'm still looking for a 12VAC transformer)
@12voltvids
6 жыл бұрын
Try swapping the tubes. If the other channel goes up, then it is likely a tube gain difference caused by low voltage. On the lower voltage, the heater won't be as hot, and this can affect tube gain, which should clear once you get the correct transformer and run the tubes at their rated voltage.
@elsaarmstrong-zp6ng
10 ай бұрын
Interesting circuit though! Fraser
@AlienRelics
5 жыл бұрын
Should be orange LEDs... looks weird with blue.
@Ahmad76715
6 жыл бұрын
29:51 getting Shocked.. lol nice project :D
@12voltvids
6 жыл бұрын
No shock, just a little spark. These don't operate at high voltage like the bigger amp I built or the tube radios I service. Those ones have 300+ volts, and that is serious voltage in those ones, with enough energy stored in the capacitors to do some damage.
@listerine-pr5lt
6 жыл бұрын
Never push all the way down semi power rectifiers to the board
@12voltvids
6 жыл бұрын
Why not? It is not like these are drawing bog power. This is a preamp.
@markanderson350
7 жыл бұрын
I can just feel 48 volts. Nice kit. Never seen a double doubler. R16, should that not be returned to ground, not -28 V
@neccron9956
6 жыл бұрын
Nice catch. If the schematic is correct, you will be floating the output at -28v. You need to see is the schematic matches the PC board.
@markanderson350
6 жыл бұрын
It is ok but when you plug it in to something or hit the input switch, you will have a heck of a pop!
@defranne4217
5 жыл бұрын
This is a preamp not a buffer
@12voltvids
5 жыл бұрын
A preamp and buffer is exactly the same thing with the exception this has an attenuator. It is live level. Give is 1 volt signal get 1 volt signal out.
@nor4277
7 жыл бұрын
Now if anyone ever build a tube radio kit,that I would buy?
@12voltvids
7 жыл бұрын
Ron Thompson There are high end amplifier kits readily available but they are expensive. Paid 1000 for my 8 wpc amp kit.
@12voltvids
7 жыл бұрын
A tube radio would be a cool build, but the problem is the tubes. Receiving tubes have not been made in over 50 years. Audio tubes are still being made, as there are tons of audio amps out there that need new tubes. So the common audio tubes are still readily available, and old radio / TV tubes are getting really hard to find.
@KRAFTWERK2K6
6 жыл бұрын
This kit is a pain in the butt to solder together when it comes with a spreadsheet that is a Black and White copy and not color like it should be. :( I ordered 2 of these once from 2 different retailers and both had the worst quality copy papersheets with the parts list and board picture on it so it's impossible to compare it properly or use as a reference. Especially when you wanna check the right position for each resistor. All the other parts are a lot easier to detect and sort out thou. However i also don't like the fact that they included Blue LEDs again into this kit and the Tube sockets are plastic, not ceramic.
@12voltvids
6 жыл бұрын
I hate to piss on your cornflakes however... The instructions that came with the kit were in full color, not black and white as you claim.I showed the color picture right at the beginning, at the 0:19 point. That looks like a color picture to me. Also, the values of the parts being installed are silk screened onto the high quality glass board and you claim that the tube sockets are plastic. Bzzzt WRONG again. They are ceramic on this kit. Now I am referring to the kit I picked up at ICStation, not knock off`s that others might be selling for a buck or 2 cheaper on fleabay. As to the blue LEDs, get over it. Nobody is forcing you to install them. You can put in whatever color you like. Green, pink, red, yellow. I persobally perfer orange, as that enhances the color of the tubes. Or you could just not install any at all, and then you would only see the tubes. Your choice, but please don`t come on here like you know everything, because there are plenty of different kits out there being sold by many. I didn`t build one of those, and I didn`t review them. I built and reviewed the one I got from ICStation from the link in the video. If you buy it somewhere else your mileage may vary.
@KRAFTWERK2K6
6 жыл бұрын
Yeah, seen it. Which is why i'm kinda pissed at the kits I got. Guess it's a bit of hit'n miss with these chinese mini-amp kits. Still thou my kits came with essentially the same parts as yours but it had plastic sockets. All the rest is pretty much the same. Yeah i left out the LEDs when i put together my first kit. Looks a lot better. And don't worry, i wasn't attacking you or anything. I know that i don't know anything. :P In fact these kits are great fun for someone who want to start soldering things without blowing too much money into the wind. It actually showed me how awesome it is to build something yourself while learning a bit about the things and how they work. So yeah, not wanting to offend you. Sorry if that came over like that. I actually found your video extremely helpful and wish I had stumbled upon it a little earlier.
@realgroovy24
6 жыл бұрын
You were lucky! Mine came with no schematic at all.
@erwinflores6364
3 жыл бұрын
What a shitty diagram putting 4.7k and 1uf capacitors in grid is not a good idea.
@12voltvids
3 жыл бұрын
Go ahead. Tell everyone why you think it is a bad design.
Пікірлер: 162