Well, I am not a total newbie, but it would be the first time I work with tube amps. I have worked with other solid state designs, and this time I would like to try something new with tubes.
What I want to build is a simple power amplifier for a pair of bookshelf speakers. Don't need a lot of power, so 10W is about enough. It can be a pair of monoblocks. Is there any design that I can get a hand on with these requirements? What tube is a good place to start off from? EL34?
Thanks in advance,
Peter
What I want to build is a simple power amplifier for a pair of bookshelf speakers. Don't need a lot of power, so 10W is about enough. It can be a pair of monoblocks. Is there any design that I can get a hand on with these requirements? What tube is a good place to start off from? EL34?
Thanks in advance,
Peter
When I was adviced about a newbe project Claus Byriths projects where recommended. 8W SE design
I am building his 30W pp amp, going on 1/2 year now.
I am building his 30W pp amp, going on 1/2 year now.
Hi Peter Pan
You make a big chance to receive lots of replies, so much that you will feel dizzy choosing one among them.
I am working (parallel at least another 5 projects...) on the baby huey, a design by Gingertube. It uses EL84 and puts out about 10W
http://www.diyaudio.com/forums/showthread.php?threadid=72536&highlight=
May I recommend a good book? Valve amplifiers, third edition by Morgan Jones
Good luck
Erik
You make a big chance to receive lots of replies, so much that you will feel dizzy choosing one among them.
I am working (parallel at least another 5 projects...) on the baby huey, a design by Gingertube. It uses EL84 and puts out about 10W
http://www.diyaudio.com/forums/showthread.php?threadid=72536&highlight=
May I recommend a good book? Valve amplifiers, third edition by Morgan Jones
Good luck
Erik
EL34 is not a bad place to start but EL84 might be better for your first amp, because it operates with 100v less B+ and is extemely easy to drive, i.e. the driver doesn't need to provide much current or swing much voltage. The fact that EL84 sounds very good in ultralinear push-pull (PP) connection doesn't hurt either.
PP is probably your best bet, because it's easier to achieve success than single-ended (SE) and the output transformer is smaller and less expensive for the same power handling. You can build two monoblocs if you want to, of course, but with EL84s it's not really necessary. A single stereo unit is perfectly feasible and more cost-effective.
Consider the 6V6GT triode connected
Also the 6GM5 is a good candidate if you can find them. There is a host of schematics and ideas. I would lean toward the octal tubes as drivers; much lower distortion. The book VALVE AMPLIFIERS by Morgan Jones is a good start, but requires some knowledge of electronics. He or his publisher doesn't believe in connection dots on his schematics. Also some of his solutions are esoteric. THE AUDOCYCLOPEDIA , a book long out of print but published by Howard Sams and edited by Howard Tremaine is an excellent book and in it are a multitudes of schematics.
Also the 6GM5 is a good candidate if you can find them. There is a host of schematics and ideas. I would lean toward the octal tubes as drivers; much lower distortion. The book VALVE AMPLIFIERS by Morgan Jones is a good start, but requires some knowledge of electronics. He or his publisher doesn't believe in connection dots on his schematics. Also some of his solutions are esoteric. THE AUDOCYCLOPEDIA , a book long out of print but published by Howard Sams and edited by Howard Tremaine is an excellent book and in it are a multitudes of schematics.
Thanks guys. Well, although this is a first time project on tubes, it isn't necessary to be cheap. I am looking forward to something that sounds different from SS, while giving me a good impression on tube amps.
andRookie: I took a look at the paper, very well written indeed. 8W version looks great, and the 30W PP version looks very nice too. Have you finished the 30W one? How does it sound?
ErikdeBest: Do you think the baby huey would be a little too many compliated for PTP wiring? This will the first time I do PTP wiring, still got some skill to learn on that.
Thanks again guys!!
andRookie: I took a look at the paper, very well written indeed. 8W version looks great, and the 30W PP version looks very nice too. Have you finished the 30W one? How does it sound?
ErikdeBest: Do you think the baby huey would be a little too many compliated for PTP wiring? This will the first time I do PTP wiring, still got some skill to learn on that.
Thanks again guys!!
I'd just add that I've built Eli's 'El Cheapo' PP amplifier from the linked schematic and thread. I did upgrade the output transformers to Dyanclone z 565s, which added an extra 100 dollars or so to the total cost. What I wanted to say was don't let the name fool you. It's a great sounding amp, and a reasonably straight forward build. That it comes at a relatively low cost is a bonus.
Scott.
Scott.
Yep, spend the money on output transformers and you won't regret it. Buy cheap ones and you will. As for power transformers and chokes, same goes. I personally am a big fan of the EL84 and 2A3 (or 6A3 or 6B4) valves, they are great sounding and you can easily build yourself a good circuit.
For a n00b I would recommend a 2A3 PP amp using vintage output transformers- this would give you a decent amount of power, use beautiful tubes, and give you flexibility- you could always swap them for EL34 or KT88 pentodes for serious grunt.
Remember, if you can lift your amp, it hasn't got enough iron!
For a n00b
I would recommend a 2A3 PP amp using vintage output transformers- this would give you a decent amount of power, use beautiful tubes, and give you flexibility- you could always swap them for EL34 or KT88 pentodes for serious grunt.Remember, if you can lift your amp, it hasn't got enough iron!
To see how this translates into practice, look at the last picture from the last tubecad blog.
http://www.tubecad.com/2006/10/blog0082.htm
Erik
This is my dream amp - I have a stack of 13E1s (15 NIB) waiting until I know enough/am confident enough to have a go at it...
The 13E1 is a beautiful valve - I presume the amp in the photo is the Billington Export special, or is it the one from his book ("Crystal Palace")?
For that matter, I saw a note on the Billington site that implied that the "Crystal Palace" is a later & improved version of the one that their "consultant" (presumably Mr. Jones) built... Anyone know for sure?
SY said:
Billington Export - see the bit about the 13E1.
I was lucky with the 13E1s - I got some many years ago, others a couple of years back when prices were more reasonable. Prices now are silly - I'm not even convinced they will sound that great.
I've yet to find anyone who's listened to a Crystal Palace - Are they that good?
Cheers
Do single ended!!!!!!!!!!(AKA "Class A" for the solid state crowd)..simple to do, of course don't expect high power...Yes read Morgan Jones, my copy is well tattered now, as for Push pull
Have you ever tried to work on something with two people, one only is using his left hand & the other is only using his right hand???? " The left doesn't know what the right is doing"!!
___________________________________Rick.........
Have you ever tried to work on something with two people, one only is using his left hand & the other is only using his right hand???? " The left doesn't know what the right is doing"!!
___________________________________Rick.........
Peter, you should try SE triode eventually, but since you said this will be your first tube project, PP might offer a smoother transition from SS.
The Baby Huey can be built point to point, but I would probably put the CCS's on a pcb or at least perf board (though I hate the stuff.)
Tossie's PP 2A3 is reported to sound especially good. He's built a tremendous number of amps, but this particular design is supposed to work especially well.
If you can live with 6 watts (you probably can) then you might consider Poinz's Musical Machine. I built something similar a while back and thought it sounded wonderful. It was missing some of the delicacy and magic of SE 2A3, but it did some things very well. I had no trouble listening to it for extended periods. I used a tube rectifier and derived a negative rail from the main ps transformer with a pair of SS diodes (i.e. a hybrid bridge.) I used that negative supply for both the long tail pair and the bias supply.
I know I've seen a schematic that Poinz drew up for a similar design using triode wired EL34 for probably something like 10 or 15 watts. I don't think he every really made that circuit public, but if you email him he'll probably send it to you.
-- Dave
The Baby Huey can be built point to point, but I would probably put the CCS's on a pcb or at least perf board (though I hate the stuff.)
Tossie's PP 2A3 is reported to sound especially good. He's built a tremendous number of amps, but this particular design is supposed to work especially well.
If you can live with 6 watts (you probably can) then you might consider Poinz's Musical Machine. I built something similar a while back and thought it sounded wonderful. It was missing some of the delicacy and magic of SE 2A3, but it did some things very well. I had no trouble listening to it for extended periods. I used a tube rectifier and derived a negative rail from the main ps transformer with a pair of SS diodes (i.e. a hybrid bridge.) I used that negative supply for both the long tail pair and the bias supply.
I know I've seen a schematic that Poinz drew up for a similar design using triode wired EL34 for probably something like 10 or 15 watts. I don't think he every really made that circuit public, but if you email him he'll probably send it to you.
-- Dave
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