You're a renaissance man, it's the first time I've seen anyone build an amp from fabricating the chassis to tweeded cabinet and nameplate ... excellent job!
Thank you for your comment. It is a fun hobby even it you just built a lot or make from scratch like I did…. Just start making stuff, you have to start somewhere.
This amplifier and how you built it is beautiful. A true work of art. Thank you for sharing. I built and rebuilt several amplifiers waay back in the seventies, so I am interested to see if I can do what you did. before I meet my maker so to speak. Much respect, Mark.
Thank you for your kind words. It's a fun hobby and you really only get better by doing. I do make mistakes.. it's how you learn from them and move on! I hope you make something as cool. I'd like to see what you come up with. Cheers!
Great contribution to folks that want to make a neat amp. There are so many iterations of these little amps. I built one that has a ez81 rectifier and runs 361v on the plates. I'm wanting to build one with a front end similar to a Matchless Clubman 35. Including the effects loop. While many folks build Champs and Kalamazoo #1's with old reel to reels , the power transformers are ideal for making these little 12bh7 amps. Plenty of 6.3v amperage in a Voice of Music VM730 to run lots of preamp tubes. Thanks for sharing so much detail for DIY builders. All the best to you and yours.
Thanks for your comments. It was a fun little project and a little different than what people tend to make. I’m working on a Dumble style higher gain version of a 1 watt amp. The video will be out shortly.
that was pretty cool, it came out real nice. i could make the chassis and the enclosure, but the amp itself, i could never do. very cool build! you should loosen your grip on the neck some, or eventually, you're going to strain your hand. i had to teach myself the same thing. thanks for cool content
Thanks for commenting. Glad you found the build cool. Yes, I do realize I do that. It is a habit formed from when I first learned how to play guitar. It was a low cost acoustic with a high action… I had to press hard so it would not buzz. Old habits are hard to break. Lol Cheers!
Very nicely done. I think the 10" speaker is a much better match for that amp than the 12 was. I agree that a spoonful of reverb really widens the sound as well. Looks great too.
Thanks. I agree with your statement. The speakers have different power ratings and firmness so that is probably why there is a difference. Being a low power amp to difference is quite noticeable. Cheers.
Hello Mike, I stumbled onto your Princeton one videos and went to town. Thanks for all your efforts. I have followed your layout pretty much as presented. I cheated with a Hammond box, though. Still waiting on a few items (tubes) and hope to fire it up soon. I built a current limiter while I was at it too. Handy item. Your vids are well done and I am really enjoying this project . I'll post a few pics when completed,and thanks again
Thanks for commenting. I'm glad you like this content. Vacuum tubes are becoming one of those lost knowledge items. Videos like mine are helping to preserve it! Please feel free to send some pics my way and I can post on my Community Page. Cheers
Thank you. It didn't cost me alot. Most of the parts I had in my parts bin. All I have to purchase was the OT. You could make a proper Champ or Princeton for a bit more but everyone makes those! lol
Really nice work! I'm finally inspired to start my project. I don't know if you did (I'll still check on your channel), but it would be great if there were videos like "typical problems", "begginers issues" and "troubleshooting". Greetings from Brazil.
Thank you. I hope it works out for you! I don’t have any “troubleshooting” videos but that is a possibility for me to do. In video 1 and 2 I do have build tips. Most issues for new builders is cold solder joints, minor wiring issues, buzz/hum due to poor grounding techniques and voltages that are off. If the amp actually works it is easy to fix all those issues. Good luck.
Covering turned out very nice! I think I'm more and more in love with tweed amps. Maybe someday I build every one of them from 5f1 to 11 or whatever :D However I'm not sure if I'll go with tweed covering cause in Poland it's pretty expensive. And I failed to find any other source of "not amp grade" tweed/twill fabric. Maybe I'll find some other useful material. Or just plain wood with shellac. Still haven't decided yet. Too many choices...
Great build series. Do you think you might build a speaker cabinet that you could plug the head into. Kinda like a mini stack. I'd build that for sure.
(1) Richard Sachs sticker for the win! ;-) (2) I just stumbled upon this series and I'm glad I did! I haven't watched (or read) everything, but do you recall the basic total cost for all the amp components (minus cabinet & speaker)? Just a ballpark figure is all I'm looking for. Thanks!
Lol, I’m glad someone noticed. He’s an interesting cat, I enjoy his ramblings and his craftsmanship. This amp build was done on a budget. I had a lot of the parts already. I guess if you had to buy everything you may be looking around $200-$250. The transformers, tubes and Electrolytic capacitors being the bulk of the cost. All the other items are cheap and easy to obtain. Cheers.
Very nice. Just watched all 3 videos and the tone is nice and smooth. I'm sure when turned up pick attack will bring out some nice growl. I was thinking about getting the little Blackstar 5 watt with 1/2 watt switch but have heard bad reviews of cheap throw away circuit boards, IC nightmares, etc. I think I'll try my hand at this little guy. I'm coming around to the fact that a 50 watt Mesa isn't the best option for bedroom playing. 😁 I'm curious how this responds to pedals. Thanks for your clear and well detailed videos.
Thanks. The cool thing about this amp and the way I build it is you can easily swap out components to tailor your sound. The amp I built does take pedals okay.... but I suspect that if you want to use drive pedals or distortion pedals you may want to install a 12AY7 to clean the amp up a bit.
great stuff mate! I was wondering if you could look at building a monster amp like a mesa boogie, even if it is just one channel of a monster amp, something that can really overdrive hard. I love the effects of el34's.
I probably won’t be making an EL34 amp anytime soon. I already have larger amps like that. I am working on a higher gain (dumble style) 1 watt amp for studio and practicing. A video of that will be posted.
Hi Mike - this is a superb video series and has motivated me to try to build my own version. What would I have to change to use and EL84 as the power tube?
Thanks. You would need a different output transformer, a power transformer that will accommodate the extra current and a different cathode resistor. Check out AX84, that website has everything you need to know.
Hi Mike I just subscribed. I have watched all three of the videos on this amp. You have built very nice sounding amp. I would like to build one similar to this one, a little higher wattage (20 watts, something I could play some small gigs with.). What about the price of your electronics to build this one, If you don't mind me asking.
Thanks. The amp I built was a budget build. I had a lot of the parts left over from other project. I did have to buy the Output transformer. I guess if I have to price it all out I suspect it would cost be around $225-$250 in all the parts. What you want to do will cost a lot more. For 20watts of power you will probably need 2-6v6 power tubes similar to a Deluxe or a Harvard. Amps like that cost more to make due to the bigger transformers and more parts needed. Good luck!
Hi Mike. I made the amp. At first the amp wasn't working, i thought, but i found out it gave sound when using the headphone jack. So the amp was working. I wired the switched speaker jack in a different way and now the amp is fully working. My DC voltages are a bit different then on your schematic. 317 vs 307 13,6 vs 12,9 1,25 vs 1,39 166 vs 156 169 vs 159 1,27 vs 1,33 In the video you said "calculating the bias". Is this necessary? I'm waiting for your next higher gain (dumble style) 1 watt amp. But first i have to make the cabinet for the amp i just finished.
That’s awesome. Thanks for letting me know. Those voltages are within spec and I suspect it has something to with line voltage and overall amp bias. The hotter the bias, the more the voltage will drop but I think you are good. I would recommend checking the power tube bias once you have it all buttoned up. More for curiosity and learning how to do it. How does it sound?
@@MikeFreda I think it sounds great, bright and loud!. There is some humm, but for a first build high voltage amp that's oké. I will check the grounding.
That’s good to hear. Chasing buzzing and ground issues is a very common issue for builders. You become a better builder when you figure it out. Sometimes it’s just the cable, house grounding or Halogen or LED bulbs. In the amp, made sure signal wires and heater wires are away from each other and cross at 90deg. Ground the back of the pots. Separate the PSU ground and the rest of the ground on the eyelet Board the run it all back to the star ground. I hope that helps?
Hi Mike, thanks for sharing the 3 video's building a 1W tube guitar amp. Great explination. Until now i have builded some low voltage tube guitar amps. I wanna give your amp a try. I have one question. In the build schematic on the input jack there is a 1M resistor. On the final layout it says a 100R resistor. I believe the right one is the 1M (looking at the color code of the resistor in the video.) Can you confirm that it should be a 1M resistor. The only thing a have to do is finding an equivalent for the 6K49VG power transformer with 220VAC primary, as i am living in the Netherlands.
Thank you for your kind works. I hope my project inspires you. Yes, that is a mistake on the input Jack. 100ohm is a typo. It needs to be a 1meg resistor. Substitution of the PT is fairly easy. There isn’t a lot of current draw. You will never see more than 40ma in this amp. The Fender standalone Reverb PT will also work you but you need to wire it as a full wave bridge. The layout has been revised. New link in description. Thanks for catching that.
Hi Mike, very nice build! Just a question: your 12AU7 tube is configured in a push-pull fashion, each side using half of the 125A output transformer. Did you try instead a single ended configuration ? Using the same components, you just will need to change some of the connections. Let me know if you are interested into a schematic.
Thanks. Yes, you can configure the output tube as a parallel single end but that requires a different output transformer. I did have to purchase a output transformer and the 125A was readily available and I suspect that a Push/Pull would provide a bit more output. Thanks for the suggestion. I may try something like that in the future.
That’s it. I got mine from Allied. I think Hammond made them for allied. You can use almost any plate transformer I. That voltage and amp range. Hammond has a bunch. You can also use the Fender Stand-alone reverb transformer but you need to use 4 diodes for a full wave bridge.
This is a great video series thanks so much Mike. I managed to build a single ended hifi amp over lockdown and to my surprise it actually works and sounds great. I am in the UK is there a UK alternative for the power transformer you are using? Thanks Glenn
Thanks! I got the transformer from Allied Electronics. Hammond makes the same one. Actually, I think Hammond makes the Allied one. You can use any Plate Transformer that has similar voltage and current properties. ~250-0-250V or 440 to 460VCT @ approx 50ma with at least 1.5Amp on the 6.3V will work fine. Try Hammond: 269GX The Fender Standalone reverb PT will also work you just need a full wave bridge rectifier. (4 diodes) I would not recommend going over my B+ voltages as described on my schematic.
@@MikeFreda Mike I remembered I bought a Hammond 369EX transformer to build a hifi preamp with. Could you advise if this would be suitable it is 380v ct @ 75ma. Thanks Glenn
Hi! Great project! I have a non working Blackstar HT5. Can I reuse his power transformer in this project? HT seem 380V. Is it necessary to adjust value of components? Thanks in advance
Yes, you should be able to re-use all the main components to make a new amp. I'm not sure of you version you have but the PT may be a Voltage Doubler. You need to figure out how to drop the voltage to the plate of the 12BH7 to ~315VDC. Some dropping resistors or a Zener Diode may work. I would recommend using the Duncan Amps Power Supply Simulator. This amp will draw around 25-30ma. Fun project!
Hey Mike, I have another question. What differences would there be for a 1 watt bass head? Would it be possible for you to do a series on that with a cabinet as well? Many thanks for your videos.
Bass amps typically like a lot of clean power. A 1 watt bass amp would only be good for practicing or possibly installing a line out for recording. You could take the circuit I did and use a 12AU7 in the preamp section to clean up the front end. I’d also go with a 10” ceramic speaker for clarity. Interesting project but I can’t see my self making something like that since I don’t really play bass.
So what can you tell me about the BlackStar ht1or ht5. Do both channels have the dioide clipping. And is there any fact in calling it a all tube amp. Or is it just a hybrid.
I do have a video on one of those amps. Have a look. These amps have a lot of solid state components in them. Some of those components are in the signal chain, some of them control the tubes bias. In these amps there is a dedicated preamp tube (12AX7) and a dedicated output tube (12BH7) that directly feeds a output transformer. I guess one could call it a Hybrid but a Hybrid to me would means a tube input section and a solid state output section or vice/versa. Cheers
I have a 5 watt/1 watt amp I really loved for about 14 months before it died....it used a 12ax7 and a 12bn7 power tube. Do you know the difference between the tube you used an the 12bn7? I hope make a point to point amp out of this amp some day.
Unfortunately, I’m not familiar with that tube. Best thing to do is look at the RCA spec sheet for both tubes and compare. I suspect it’s in the same family of this sort of tube.
@@MikeFreda thank you so much for your response. Well I was wrong. I pulled the original papers on the amp and it is actually the 12bh7! I loved the clean plus the ability to get huge feedback at t.v. levels. It's a bugera g5 infinimum head. I registered it for warranty never heard from them, call support nothing. Took it to an old school tech he couldn't troubleshoot or even find a schematic for it. I will never buy another product from the "tribe" again. But I'm so thankful you built your amp making it simple for me to duplicate. Thank you again.
Hello, The chassis is 11.5" long x 7" wide x 2" tall. The tube sockets are spaced 1.25" from the back edge and 1.5" and 4" from the right side. I'm sure you can figure out the rest from laying out the parts and/or drawing it full scale on a piece of paper, cheers.
I just tried it and it works for me. Please update your browser or use a different one. If not, please email me and I can send you the build documents. Email address in the about section of my page.
Part 1 Video: czcams.com/video/JKoEprk4eaU/video.html
You're a renaissance man, it's the first time I've seen anyone build an amp from fabricating the chassis to tweeded cabinet and nameplate ... excellent job!
Thank you for your comment. It is a fun hobby even it you just built a lot or make from scratch like I did…. Just start making stuff, you have to start somewhere.
This amplifier and how you built it is beautiful. A true work of art. Thank you for sharing. I built and rebuilt several amplifiers waay back in the seventies, so I am interested to see if I can do what you did. before I meet my maker so to speak. Much respect, Mark.
Thank you for your kind words. It's a fun hobby and you really only get better by doing. I do make mistakes.. it's how you learn from them and move on! I hope you make something as cool. I'd like to see what you come up with. Cheers!
Great contribution to folks that want to make a neat amp. There are so many iterations of these little amps. I built one that has a ez81 rectifier and runs 361v on the plates. I'm wanting to build one with a front end similar to a Matchless Clubman 35. Including the effects loop. While many folks build Champs and Kalamazoo #1's with old reel to reels , the power transformers are ideal for making these little 12bh7 amps. Plenty of 6.3v amperage in a Voice of Music VM730 to run lots of preamp tubes. Thanks for sharing so much detail for DIY builders. All the best to you and yours.
Thanks for your comments. It was a fun little project and a little different than what people tend to make. I’m working on a Dumble style higher gain version of a 1 watt amp. The video will be out shortly.
Really! Really! Cool!! ~cheers
Thanks. Glad you liked it. Cheers.
Excellent series; explanations are very good along the way. Thanks for sharing this one.
Thanks and you’re welcome.
Hi Mike! Been enjoying all of your videos! Very well organized and great presentation of informations.
Thanks for commenting. I’m glad you like my content. Cheers
that was pretty cool, it came out real nice. i could make the chassis and the enclosure, but the amp itself, i could never do. very cool build! you should loosen your grip on the neck some, or eventually, you're going to strain your hand. i had to teach myself the same thing. thanks for cool content
Thanks for commenting. Glad you found the build cool. Yes, I do realize I do that. It is a habit formed from when I first learned how to play guitar. It was a low cost acoustic with a high action… I had to press hard so it would not buzz. Old habits are hard to break. Lol Cheers!
Very nicely done. I think the 10" speaker is a much better match for that amp than the 12 was. I agree that a spoonful of reverb really widens the sound as well. Looks great too.
Thanks. I agree with your statement. The speakers have different power ratings and firmness so that is probably why there is a difference. Being a low power amp to difference is quite noticeable. Cheers.
Hello Mike,
I stumbled onto your Princeton one videos and went to town. Thanks for all your efforts. I have followed your layout pretty much as presented. I cheated with a Hammond box, though. Still waiting on a few items (tubes) and hope to fire it up soon. I built a current limiter while I was at it too. Handy item. Your vids are well done and I am really enjoying this project . I'll post a few pics when completed,and thanks again
Thanks for commenting. I'm glad you like this content. Vacuum tubes are becoming one of those lost knowledge items. Videos like mine are helping to preserve it! Please feel free to send some pics my way and I can post on my Community Page. Cheers
Most effort and money for 1 watt great build
Thank you. It didn't cost me alot. Most of the parts I had in my parts bin. All I have to purchase was the OT. You could make a proper Champ or Princeton for a bit more but everyone makes those! lol
Really nice work! I'm finally inspired to start my project.
I don't know if you did (I'll still check on your channel), but it would be great if there were videos like "typical problems", "begginers issues" and "troubleshooting".
Greetings from Brazil.
Thank you. I hope it works out for you! I don’t have any “troubleshooting” videos but that is a possibility for me to do.
In video 1 and 2 I do have build tips.
Most issues for new builders is cold solder joints, minor wiring issues, buzz/hum due to poor grounding techniques and voltages that are off. If the amp actually works it is easy to fix all those issues.
Good luck.
Covering turned out very nice! I think I'm more and more in love with tweed amps. Maybe someday I build every one of them from 5f1 to 11 or whatever :D However I'm not sure if I'll go with tweed covering cause in Poland it's pretty expensive. And I failed to find any other source of "not amp grade" tweed/twill fabric. Maybe I'll find some other useful material. Or just plain wood with shellac. Still haven't decided yet. Too many choices...
Very Nice 👏🏼👏🏼
Great build series. Do you think you might build a speaker cabinet that you could plug the head into. Kinda like a mini stack. I'd build that for sure.
Thanks. Yes, that is the plan. I’m planning a part 4 video that will show that and do a proper/good audio clips.
(1) Richard Sachs sticker for the win! ;-) (2) I just stumbled upon this series and I'm glad I did! I haven't watched (or read) everything, but do you recall the basic total cost for all the amp components (minus cabinet & speaker)? Just a ballpark figure is all I'm looking for. Thanks!
Lol, I’m glad someone noticed. He’s an interesting cat, I enjoy his ramblings and his craftsmanship. This amp build was done on a budget. I had a lot of the parts already. I guess if you had to buy everything you may be looking around $200-$250. The transformers, tubes and Electrolytic capacitors being the bulk of the cost. All the other items are cheap and easy to obtain. Cheers.
Very nice. Just watched all 3 videos and the tone is nice and smooth. I'm sure when turned up pick attack will bring out some nice growl.
I was thinking about getting the little Blackstar 5 watt with 1/2 watt switch but have heard bad reviews of cheap throw away circuit boards, IC nightmares, etc.
I think I'll try my hand at this little guy.
I'm coming around to the fact that a 50 watt Mesa isn't the best option for bedroom playing. 😁
I'm curious how this responds to pedals.
Thanks for your clear and well detailed videos.
Thanks. The cool thing about this amp and the way I build it is you can easily swap out components to tailor your sound. The amp I built does take pedals okay.... but I suspect that if you want to use drive pedals or distortion pedals you may want to install a 12AY7 to clean the amp up a bit.
Awesome
great stuff mate! I was wondering if you could look at building a monster amp like a mesa boogie, even if it is just one channel of a monster amp, something that can really overdrive hard. I love the effects of el34's.
I probably won’t be making an EL34 amp anytime soon. I already have larger amps like that. I am working on a higher gain (dumble style) 1 watt amp for studio and practicing. A video of that will be posted.
Luar biasa, kreatif
Thank you.
Hi Mike - this is a superb video series and has motivated me to try to build my own version. What would I have to change to use and EL84 as the power tube?
Thanks. You would need a different output transformer, a power transformer that will accommodate the extra current and a different cathode resistor. Check out AX84, that website has everything you need to know.
@@MikeFreda Thank you for the pointer, will read up!
Hi Mike I just subscribed. I have watched all three of the videos on this amp. You have built very nice sounding amp. I would like to build one similar to this one, a little higher wattage (20 watts, something I could play some small gigs with.). What about the price of your electronics to build this one, If you don't mind me asking.
Thanks. The amp I built was a budget build. I had a lot of the parts left over from other project. I did have to buy the Output transformer. I guess if I have to price it all out I suspect it would cost be around $225-$250 in all the parts. What you want to do will cost a lot more. For 20watts of power you will probably need 2-6v6 power tubes similar to a Deluxe or a Harvard. Amps like that cost more to make due to the bigger transformers and more parts needed. Good luck!
Hi Mike. I made the amp. At first the amp wasn't working, i thought, but i found out it gave sound when using the headphone jack. So the amp was working.
I wired the switched speaker jack in a different way and now the amp is fully working.
My DC voltages are a bit different then on your schematic.
317 vs 307
13,6 vs 12,9
1,25 vs 1,39
166 vs 156
169 vs 159
1,27 vs 1,33
In the video you said "calculating the bias". Is this necessary?
I'm waiting for your next higher gain (dumble style) 1 watt amp. But first i have to make the cabinet for the amp i just finished.
That’s awesome. Thanks for letting me know. Those voltages are within spec and I suspect it has something to with line voltage and overall amp bias. The hotter the bias, the more the voltage will drop but I think you are good.
I would recommend checking the power tube bias once you have it all buttoned up. More for curiosity and learning how to do it.
How does it sound?
@@MikeFreda I think it sounds great, bright and loud!. There is some humm, but for a first build high voltage amp that's oké.
I will check the grounding.
That’s good to hear. Chasing buzzing and ground issues is a very common issue for builders. You become a better builder when you figure it out. Sometimes it’s just the cable, house grounding or Halogen or LED bulbs.
In the amp, made sure signal wires and heater wires are away from each other and cross at 90deg. Ground the back of the pots. Separate the PSU ground and the rest of the ground on the eyelet Board the run it all back to the star ground. I hope that helps?
Thanks for your advice.
Hi Mike, thanks for sharing the 3 video's building a 1W tube guitar amp. Great explination. Until now i have builded some low voltage tube guitar amps. I wanna give your amp a try.
I have one question. In the build schematic on the input jack there is a 1M resistor. On the final layout it says a 100R resistor. I believe the right one is the 1M (looking at the color code of the resistor in the video.) Can you confirm that it should be a 1M resistor.
The only thing a have to do is finding an equivalent for the 6K49VG power transformer with 220VAC primary, as i am living in the Netherlands.
Thank you for your kind works. I hope my project inspires you. Yes, that is a mistake on the input Jack. 100ohm is a typo. It needs to be a 1meg resistor.
Substitution of the PT is fairly easy. There isn’t a lot of current draw. You will never see more than 40ma in this amp. The Fender standalone Reverb PT will also work you but you need to wire it as a full wave bridge.
The layout has been revised. New link in description. Thanks for catching that.
@@MikeFreda Thank you Mike.
Отлично!
Thank you.
Hi Mike, very nice build! Just a question: your 12AU7 tube is configured in a push-pull fashion, each side using half of the 125A output transformer. Did you try instead a single ended configuration ? Using the same components, you just will need to change some of the connections. Let me know if you are interested into a schematic.
Thanks. Yes, you can configure the output tube as a parallel single end but that requires a different output transformer. I did have to purchase a output transformer and the 125A was readily available and I suspect that a Push/Pull would provide a bit more output. Thanks for the suggestion. I may try something like that in the future.
Good Night my Youth A beautiful project Can you share the schematics? Thanks
All the build information is in the description as stated in the video. Cheers.
Hi Mike, great job, I love it ;). Would you please have a link or a ref for the PT ?
www.newark.com/hammond/6k49vg/power-tx-50-60hz/dp/31AJ8672
That’s it. I got mine from Allied. I think Hammond made them for allied.
You can use almost any plate transformer I. That voltage and amp range. Hammond has a bunch. You can also use the Fender Stand-alone reverb transformer but you need to use 4 diodes for a full wave bridge.
This is a great video series thanks so much Mike. I managed to build a single ended hifi amp over lockdown and to my surprise it actually works and sounds great. I am in the UK is there a UK alternative for the power transformer you are using? Thanks Glenn
Thanks! I got the transformer from Allied Electronics. Hammond makes the same one. Actually, I think Hammond makes the Allied one.
You can use any Plate Transformer that has similar voltage and current properties.
~250-0-250V or 440 to 460VCT @ approx 50ma with at least 1.5Amp on the 6.3V will work fine.
Try Hammond: 269GX
The Fender Standalone reverb PT will also work you just need a full wave bridge rectifier. (4 diodes)
I would not recommend going over my B+ voltages as described on my schematic.
@@MikeFreda thanks for the advice Mike that’s brilliant I will see what I can track down 👍
@@MikeFreda Mike I remembered I bought a Hammond 369EX transformer to build a hifi preamp with. Could you advise if this would be suitable it is 380v ct @ 75ma. Thanks Glenn
Yes, that will work. B+ will a bit low, you may have to adjust your PSU dropping resistors. (A little lower value).
@@MikeFreda Thanks again Mike sounds like a plan.👍
Hi! Great project! I have a non working Blackstar HT5. Can I reuse his power transformer in this project? HT seem 380V. Is it necessary to adjust value of components? Thanks in advance
Yes, you should be able to re-use all the main components to make a new amp. I'm not sure of you version you have but the PT may be a Voltage Doubler. You need to figure out how to drop the voltage to the plate of the 12BH7 to ~315VDC. Some dropping resistors or a Zener Diode may work. I would recommend using the Duncan Amps Power Supply Simulator. This amp will draw around 25-30ma. Fun project!
@@MikeFreda Thank you. I suppose I must deal with the heater too, since it's 19V out of the transfo. Maybe I can reuse the 2 LM 317 of the Blackstar.
Hey Mike, I have another question.
What differences would there be for a 1 watt bass head? Would it be possible for you to do a series on that with a cabinet as well? Many thanks for your videos.
Bass amps typically like a lot of clean power. A 1 watt bass amp would only be good for practicing or possibly installing a line out for recording. You could take the circuit I did and use a 12AU7 in the preamp section to clean up the front end. I’d also go with a 10” ceramic speaker for clarity. Interesting project but I can’t see my self making something like that since I don’t really play bass.
The links don't work for build doc.
They seem to work for me and link appropriately. Try updating your browser. If not, I can email you all the docs. Thx.
So what can you tell me about the BlackStar ht1or ht5. Do both channels have the dioide clipping. And is there any fact in calling it a all tube amp. Or is it just a hybrid.
I do have a video on one of those amps. Have a look. These amps have a lot of solid state components in them. Some of those components are in the signal chain, some of them control the tubes bias. In these amps there is a dedicated preamp tube (12AX7) and a dedicated output tube (12BH7) that directly feeds a output transformer. I guess one could call it a Hybrid but a Hybrid to me would means a tube input section and a solid state output section or vice/versa. Cheers
I appreciate the response.
I have a 5 watt/1 watt amp I really loved for about 14 months before it died....it used a 12ax7 and a 12bn7 power tube. Do you know the difference between the tube you used an the 12bn7? I hope make a point to point amp out of this amp some day.
Unfortunately, I’m not familiar with that tube. Best thing to do is look at the RCA spec sheet for both tubes and compare. I suspect it’s in the same family of this sort of tube.
@@MikeFreda thank you so much for your response. Well I was wrong. I pulled the original papers on the amp and it is actually the 12bh7! I loved the clean plus the ability to get huge feedback at t.v. levels. It's a bugera g5 infinimum head. I registered it for warranty never heard from them, call support nothing. Took it to an old school tech he couldn't troubleshoot or even find a schematic for it. I will never buy another product from the "tribe" again. But I'm so thankful you built your amp making it simple for me to duplicate. Thank you again.
Can you please include the chassis specs? Thank you
I need the hole/cut outs and spacing. Thank you
Hello, The chassis is 11.5" long x 7" wide x 2" tall. The tube sockets are spaced 1.25" from the back edge and 1.5" and 4" from the right side. I'm sure you can figure out the rest from laying out the parts and/or drawing it full scale on a piece of paper, cheers.
Nice job Mike...how did you make that decal ?
Thanks. I made another CZcams video on how I did that. Just search it on my channel.
Hi, the schematic link not working for me....
I just tried it and it works for me. Please update your browser or use a different one. If not, please email me and I can send you the build documents. Email address in the about section of my page.
@@MikeFreda ah yes it works on my desktop thank you so much...cheers
Hi Mike, do you have an email contact for a business inquiry? Thanks.
Yes, I have a email address linked on my Channel Homepage. On the Desktop version, go to my Channel > About > View Email.
Deckle? Ohhh, a decal. 😂
Lol... well, I’m Canadian, that’s how we say it.