Since your review Douk has modified the design and dropped off the loudness filter. Also there are currently larger cutouts in the bottom (under transformers) plate, to allow wires to go down the circuit board. They listened to what you had said.
i got this kit just recently with the loudness out still, and they re-orientated the transformers to the best position. i notice they reference these vids on the sales page for guidance too =) . really helpful Tony . thanks.
The ECC and EL are European (British) designs. Likely making parts from British Vac tube lines. Woa - where is the input DC isolation cap that is in series of "1" and "2" after the volume pot and before the vac tube pre-amp. That isolates the bias from blowing up the phone or whatever you put on. No dc blocking !
What about running 2 light bulbs either side of the volume pot?? Maybe 5 Watts each I was hoping you a do a full frequency response and test for THD why didn't you do that.
Hi Tony, been watching your channel for a while now with much interest & admiration. My wife tells me you have a happy & soothing voice. I've been looking at the products from this eBay seller for some time now & they have mixed reviews. Your knowledge just oozed out of this kit build video & also the F28 series. Although it may not have been your intention, this is one of the best reviews I've seen. You even hinted at some improvements which I hope you explore in the future, (a kit manufacturers dream come true). If you end up doing those improvements it would be interesting to see the before & after performance of this amp. And then you go & play some music from one of my all time favorite bands, sadly Walter is no longer with us. Keep up the great work Tony.
Reminds me of my grand and classic radio engineers instructors I had years back during my undergrad years - the last of the Tube Mohicans in the days where the transistor and ICs is king. It seemed tubes is having a renaissance. Analog electronics is enduring and builds a lot of discipline in your hands and head. Thank you Sir for these I think I will build one too after seeing this.
My understanding is that the Nichicon FG Fine Gold and KZ Muse Audio Grade caps have a min impedance at 120Hz as opposed to 100kHz typical of "low esr" caps intended for switching supplies. The electrolyte has better audio characteristics and smooth foil is used in the KZ types. Etched foil in miniature electrolytics is noisy due to the increased crystal boundaries. Generally speaking electrolytics in general should not be used in the signal path unless dc biased and bypass caps (preferably not polyester/Mylar) should be used, the higher the better fit considered.
I like when you build the kits. Please do some more. I also like your approach to the repairs you do. Your troubleshooting is helping me along with how you explain the theory of how it should work. Keep the videos coming.
@@InsideOfMyOwnMind A good assumption, but caps are cheap. There's no reason they couldn't have popped one in just in case a broken pre-amp is ever hooked up.
I also has a Hantek USB scope, its a 6022BE and it has the same noise as yours do. I was worried it might be some damage or fault, but I guess its just because its cheap. Haha. But works great for biasing and minor checking!
What load are the outputs loaded to when you measure the waveforms ? if Not a Resistor load, there is an impedance mismatch. That will distort the signal and might draw more current in the primary as the secondary is not loading the inductive transformer. The Audio caps are simply low inductance and low resistance to the plates. Otherwise you will have frequency filtering but on a power supply it doesn't matter.
Great series. Thank you. What would be a fun video project would be if you repurposed the eye tube sockets to a preamp circuit. With you knowledge and skills I think it would be very educational.
What is the gain of this amplifier? Alternatively,what was the rms voltage of the 1khz tone which achieved 10v rms at the output. I was just wondering if a consumer cd player or tuner will be able to achieve the 12 watts per channel on direct connection.
I ordered one of these today. I'm pretty good at building and soldering but I know next to nothing about electronics. I think I'm going to kill myself with this.
A guitar amp usually has a output of 50 watts rms. That requires a output transformer that can handle at least that. Weight of transformer is 8-10 pounds. Stereo u need 2 plus power transformer, 30 lbs total. Hammond sell these.
Tony, when a preamp is connected to the input, it has a much lower output impedance than 470k, even a valve one. Why doesn't that cause a similar problem to shunting the input resistor with a 50k pot? Thanks for sharing the project! M
Assuming that you, like me, don't have a pair of corner horn Klipschs, for maximum volume from 12 Watts, what speakers would you recommend? At least we're far from the age of Advent speakers! They sucked up all the power they could get!
Note, one way to turn a linear potentiometer to an audio is to put a resistor (a larger resistor) on the wiper arm of the pot to signal ground. Two, what is the output impedance of the audio transformer? Three how is there no DC voltage at the outputs of the speaker transformer? given the path from R3 through R5 on to W1 there should be a DC level, which should put it on the audio secondary leads.
The DC resistance of the output transformer will be quite low. I'd expect less than 8 ohms. Based on some quick calculations, I'd expect it to be around 0.003V or less.
ey man can you help me i got an amp kit today with the worst directions and they failed to label all my parts. Hey man, I have the best answer to your problem. Don´t buy junk !
Would like to see you do modifications for the quality of sound and its output ability. Do some before and after distortion test. Some before and after frequency response test.
the general design inspiration is a mixed copy of BRAUN's CV11 & CSV13 plus BRAUN's CE11 radio's magic eyes
Steely dan,the best way to break in ANY amp!!
Russel Harris agreed 'it will come back to you'. Not sure about the Van Halen at the end though? 😂😂😂
Since your review Douk has modified the design and dropped off the loudness filter. Also there are currently larger cutouts in the bottom (under transformers) plate, to allow wires to go down the circuit board. They listened to what you had said.
i got this kit just recently with the loudness out still, and they re-orientated the transformers to the best position. i notice they reference these vids on the sales page for guidance too =) . really helpful Tony . thanks.
Hmm. The grid stop resistors are 1K 1 WATT, just HOW much current is expected to flow though these poor grids?!
I see you rotated the output transformers 90 degrees. Just what I thought would've been the fix !
The ECC and EL are European (British) designs. Likely making parts from British Vac tube lines. Woa - where is the input DC isolation cap that is in series of "1" and "2" after the volume pot and before the vac tube pre-amp. That isolates the bias from blowing up the phone or whatever you put on. No dc blocking !
Yes love those magic eyes good stuff.
What about running 2 light bulbs either side of the volume pot?? Maybe 5 Watts each
I was hoping you a do a full frequency response and test for THD why didn't you do that.
Hi Tony, been watching your channel for a while now with much interest & admiration.
My wife tells me you have a happy & soothing voice.
I've been looking at the products from this eBay seller for some time now & they have mixed reviews.
Your knowledge just oozed out of this kit build video & also the F28 series.
Although it may not have been your intention, this is one of the best reviews I've seen.
You even hinted at some improvements which I hope you explore in the future, (a kit manufacturers dream come true).
If you end up doing those improvements it would be interesting to see the before & after performance of this amp.
And then you go & play some music from one of my all time favorite bands, sadly Walter is no longer with us.
Keep up the great work Tony.
This was really fun to watch thanks for taking the time to do it, love the channel.
funny how you like the magic eye tubes but don't like the orange LEDs to light up the tube? those magic eyes look cheap and gimmicky, sorry.
Reminds me of my grand and classic radio engineers instructors I had years back during my undergrad years - the last of the Tube Mohicans in the days where the transistor and ICs is king. It seemed tubes is having a renaissance. Analog electronics is enduring and builds a lot of discipline in your hands and head. Thank you Sir for these I think I will build one too after seeing this.
why don't you show the power suply diagram .
Is nothing Bias-Trimmer for 6E2🤔
My understanding is that the Nichicon FG Fine Gold and KZ Muse Audio Grade caps have a min impedance at 120Hz as opposed to 100kHz typical of "low esr" caps intended for switching supplies. The electrolyte has better audio characteristics and smooth foil is used in the KZ types. Etched foil in miniature electrolytics is noisy due to the increased crystal boundaries. Generally speaking electrolytics in general should not be used in the signal path unless dc biased and bypass caps (preferably not polyester/Mylar) should be used, the higher the better fit considered.
it seems to me very sophisticated as well sounds and designedfor peanuts. THE OUTPUT POWER COULB BE ENOUGH FOR HOUSEHOLD HI-FI FANS
How much money do you have in the entire project? Thanks. And thanks for the two videos.
I like when you build the kits. Please do some more. I also like your approach to the repairs you do. Your troubleshooting is helping me along with how you explain the theory of how it should work. Keep the videos coming.
Could the 'magic eye' tubes be wired to monitor the signal BEFORE the volume control?
Oscilloscope? At first I thought you were getting ready to heat up some lunch🍵🤭
I am also puzzled as to why there is no D.C. blocking capacitor at the input to the valve grid.
It certainly seems to be making some assumptions as to circuit design of your pre-amp.
@@russellhltn1396 Yeah,the assumption is if there is dc coming out your preamp....it's broken.
@@InsideOfMyOwnMind A good assumption, but caps are cheap. There's no reason they couldn't have popped one in just in case a broken pre-amp is ever hooked up.
Tony; Thanks for this video. Enjoyed it very much.
29:04 - So, at that point is the grid acting as a 'current sink', creating a (noisy) voltage-drop across the grid stop resistor?
I also has a Hantek USB scope, its a 6022BE and it has the same noise as yours do. I was worried it might be some damage or fault, but I guess its just because its cheap. Haha. But works great for biasing and minor checking!
th-cam.com/video/Znwp0pK8Tzk/w-d-xo.html
Fantastic Video ! Thanks .
Excellent video. Nice design as well.
What load are the outputs loaded to when you measure the waveforms ? if Not a Resistor load, there is an impedance mismatch. That will distort the signal and might draw more current in the primary as the secondary is not loading the inductive transformer. The Audio caps are simply low inductance and low resistance to the plates. Otherwise you will have frequency filtering but on a power supply it doesn't matter.
Here's a link to the type of audio dummy load I use. Thanks for the comment!
th-cam.com/video/QS8GgUWnbq0/w-d-xo.html
I see you have a Pioneer KP-500 Car Stereo there
Damn these kits are cheap
22:50 - I can understand 'audio grade' capacitors. I DON'T understand the meaning of 'computer grade', however :)
Increased cooling capacity for continuous duty, mostly in old main frames.
Nice build 👍
Great series. Thank you. What would be a fun video project would be if you repurposed the eye tube sockets to a preamp circuit. With you knowledge and skills I think it would be very educational.
Great videos both part 1 and 2
What is the gain of this amplifier?
Alternatively,what was the rms voltage of the 1khz tone which achieved 10v rms at the output.
I was just wondering if a consumer cd player or tuner will be able to achieve the 12 watts per channel on direct connection.
The ARION ACOUSTICS amp has a steel mesh cover which will keep little fingers out and maybe that would be the way to go.
I ordered one of these today. I'm pretty good at building and soldering but I know next to nothing about electronics. I think I'm going to kill myself with this.
R u okay? Did it work?
It's been 11 months ... have you survived?
A guitar amp usually has a output of 50 watts rms. That requires a output transformer that can handle at least that. Weight of transformer is 8-10 pounds. Stereo u need 2 plus power transformer, 30 lbs total. Hammond sell these.
Joe Satriani.. Surfin with the Alien. Awesome video and sound clip
Tony, when a preamp is connected to the input, it has a much lower output impedance than 470k, even a valve one. Why doesn't that cause a similar problem to shunting the input resistor with a 50k pot? Thanks for sharing the project! M
Assuming that you, like me, don't have a pair of corner horn Klipschs, for maximum volume from 12 Watts, what speakers would you recommend? At least we're far from the age of Advent speakers! They sucked up all the power they could get!
I know very little in soldering and nothing about electronics . But sure wish to learn how. You were very informative
Fantastic.
What will it sound like as a guitar amp? Will an electric guitar pickup have enough drive?
What scope are you using with that monitor?
Tony,
What's the title of your oscilloscope app?
^^ Second
Cathadyne phase inverter too easy and simple
I really would like a video about the tweaks you suggested!
Note, one way to turn a linear potentiometer to an audio is to put a resistor (a larger resistor) on the wiper arm of the pot to signal ground. Two, what is the output impedance of the audio transformer? Three how is there no DC voltage at the outputs of the speaker transformer? given the path from R3 through R5 on to W1 there should be a DC level, which should put it on the audio secondary leads.
The DC resistance of the output transformer will be quite low. I'd expect less than 8 ohms. Based on some quick calculations, I'd expect it to be around 0.003V or less.
Nice!! Thanks for sharing!!
Cool project, thanks!
Love testing
BECKER AND FAGIN !
Peg!
hey man can you help me i got an amp kit today with the worst directions and they failed to label all my parts
ey man can you help me i got an amp kit today with the worst directions and they failed to label all my parts. Hey man, I have the best answer to your problem. Don´t buy junk !
19:15 "The cathode is the long lead ..." uh oh. Really?
This looks like a fun project. I need a new amp
How hard to turn this into an 18w Mono Block?
Are there tone controls in this amplifier?
Nope, you would do that in a preamp stage.
the amp sounds good! what speakers are they?
Steely Dan, glad you kept it old school, nice series.
Would like to see you do modifications for the quality of sound and its output ability. Do some before and after distortion test. Some before and after frequency response test.