Power tube amp for guitar

I would not do the Phoenix but the 18 Watt Lite.


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Layout Minimalist. Has SS diodes instead of tube rectifier.

http://rh-tech.org/public/18-Watt/18W_minimalist_layout2.pdf


Or



18wattLite2b.gif

18W_LITE2B_LAYOUT_BrownNote_TRANS_FINAL_v1.1.jpg
 
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I want to build a power amp . Only clean volume To add pedals for preamp sections . . I search and I found the Chinese mooer TE-20 .. I don’t find the schematic but I found that have 2x el84 - 1x ecc83 and 1x ecc81 …for overdrive amps I build my Marshall clone 1974x( 18 watts) and the orange clone dark terror (7 and 15 watts ) . Now I need to build a clean power amp .


So I missed this, you have built two EL84 amps and now want to build another but want more power? How is the new amp going to give you more power?



Bassman (Marshall) tone stack


An externally hosted image should be here but it was not working when we last tested it.



Fender Blackface values.


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Ohh now I see .. thank you Printer2 for EQ . I have build 2 amps as well at 15 and 18 watt , I don’t need more . But I just want to make something with less gain stage to add pre amp emulator pedals … but now I’m ok with Phoenix .and I put the EQ for something different from my other amps ..
 
I don’t need more....


I think that is a common refrain around here. I thought the 18 Watt simpler and do real difference in output. I have started on an EL84 amp but it is on the back burner for now. Not a lot different in concept. This is only a working schematic, room for change yet.



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this is what I wanted to know, whenever for less gain I will remove the capacitors from the grid of v1 (pin: 3-8)

And something else the schematic of Phoenix say to some grounded on OT/power ground and some grounded on pre amp star ground . normally everything has to be grounded with the chassis. Why here he groups them?!?!
 
Sorry, missed bottom 2 lines.

The "Phoenix" is actually a Dr Z Carmen Ghia but they didn´t want to infringe on the brand.

Killer *simple* amp (2 knobs), that´s why I suggested it.

A little red monster! The Dr. Z Carmen Ghia 18 watt EL84 head! With a Fender CS Masterbuilt Tele! - YouTube

Personally I would build it in full, to use as flat power amp add a switching jack feeding the volume pot and bypassing first pramp stage, BUT you can also use it on its own in an emergency.

220+220VAC with SS rectifiers will give you needed ~300V DC

YOU asked for EL84 and "20W" so I suggested closest I could find.

Speaker impedance?:
you will buy an "18-20W" 2 x EL84 transformer which will have 4-8-16 ohm taps, at least 2 of them, use the one matching your speakers.

EDIT: 5751 is a tamer, supposedly premium 12AX7 sister, I would straight use 12AX7 or 12AT7 which are easily available.





For testing I take a transformer with 24v + 24v output .. I put on one ac cable the 1n4007 and on the second the another 1n4007 and those 2 cables with diode put it together .. the current drop to 23.05vdc . why? As you say I use 220v+220v with couple of 1n4007 the current goes around ~300vdc .. I.e. 1.41 x 220 = 310 vdc … what I’m do wrong ?
 
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Not sure what your problem is.

PLEASE call Voltge: VOLTAGE and current: CURRENT, they are NOT the same.

I put on one ac cable the 1n4007 and on the second the another 1n4007 and those 2 cables with diode put it together
You use transformer and diodes and nothing else?
The power supply uses that to charge a Capacitor.

I suggest you build a project which is amply documented, say a Ceriatone or similar, including a full layout and wiring image, so you get *build* answers by looking at it.

Build it exactly as is, and only Mod needed will be adding a "direct to power amp" input jack so as to meet your needs.

Feel free to ask about it when you decided on which model to build and post images here, just in case.

Schematic is the most important part on a build, but not enough on its own unless you have built a few and can smoothly match schematic, layout drawing and actual parts on a metal chassis.

They "are" the same but do not "look" the same to human eye, you (anybody) need practice for that.
 
Send input jack straight to P1 and call it "Volume"

Replace 5Y3 with a couple 1N4007 and lower suggested PT voltage to compensate that.
Say 220+220V secondary, not highervthan 2 x 240V, you won´t need the 5V filament winding.

I thought of something .. to avoid the gain of the first tube. I thought of putting a master volume. so the volume of tube rename in gain… I will have the gain control to a point where my signal does not mess up and I will have the master volume .. how does it sound to you? I made the master volume based on Marshall 1974x mod (master volume by tube depot)C41588DA-40D8-40B1-8599-AE04A3E1A37F.png
 
That pot looks backward. It shorts-out the 12AT7 at minimum volume. Yes softer, but also grossly distorted. You may need to try it the other way.

More to the point: it is inside the loop feedback. So at first it will do "nothing". When it finally takes a bite, the sound may change significantly.

Are you just over-thinking a volume control?