Yes I know, but I hate to waste excess transformer capacity.
I built a SE amp a while back with a 6AQ5 and a 8" public address speaker which sounded fine but it could not play clean loud enough for me. Distorted was another story. Probably was shy of 5W but with a good speaker it might have been ok. The reason I wanted to use the 8" I did was they are cheap and I wanted to put together a design that some kid could build for a few bucks and be happy (surprise, kind of the reasoning behind this thread). Not really complaining of the limit, after all 10 watts is not really all that much louder.
Cost wise the transformers is going to be most of my budget. Want to try the 70v transformer thing to shave a few bucks. Never tried it before so it should be interesting. I would have liked a PI but that went by the wayside to stay in the budget. I would have liked to do it with the addition of a MOSFET but they do not seem to be the flavor of the day.
This is my concern, too. These little amps seem destined for metal, although I do hear some praises for cleans in a few commercial jobs in the 150 - $200 range. I really hope some the entrants here are trying to address that end of things. I've heard it said that "you can always add dirt but you can't add clean" or something like that.
What this country needs is a good 16 ohm tube!
Or maybe a good 5Kohm speaker?
How about a Circlotron or other transformerless design? On second thought, the cost is limited to less than $2000 and it can't kill you. Darn.
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I mean the amp that will sound on 1 meter distance like a famous stage amp on 100 meter distance. The same sound.
I'm thinking maybe a gain switch or something that is labelled "Fender" on one side and "Marshall" on the other.
Yes, but there should be 2 amps in 1 box.
I am building a rather ordinary push pull amp. The 5 tubes are all single unit tubes, pentode input, triode gain stage to recover tone stack losses, triode PI, pair of pentode outputs. There are some rather creative tricks pulled to save money on the circuitry, so I would have it to spend on things like pots and switches. Guitar players like knobs to turn, speaking of knobs, anyone found them cheap yet?
After it is all working I plan to tweak it and change out entire stages if necessary. The spreadsheet told me that this was the best bang for the buck so I started here. There are two alternate P-P designs using multi section tubes at similar costs. I may build them all and test if I have time.
I have been making SE champ style amps going back as far as 7th grade, and I am nearly 60 now, so I doubt I will go there unless I get a wild hair........
6BA6 is a decent choice to scale down a classic guitar amp. I am going with a directly heated cathode version.
Tone control action is an area I think is of some importance, along with modeling the distortion vs volume curves but at a lower level.
5W is plenty even live, throw a mic in front of it and you are good to go.
Check out the old Live Clips of the Faces, Ron Wood used an old Fender Silver Face Champ.
YouTube - Rod stewart & it's the faces stay with me live uk
You can see it tucked away stage left, right behind him. 0:56 & 1:36 into the video.
Then look at cleans,
Ole Jeff Beck is using tiny amps on tour right now with Imelda May.
YouTube - Jeff Beck with Imelda May-Tiger Rag (Based on a 1917 song by the Original Dixieland Jass Band)
Did the same thing on the Les Paul Tribute
YouTube - Jeff Beck honors Les Paul [Best of Guitar-Tube]
Check out the old Live Clips of the Faces, Ron Wood used an old Fender Silver Face Champ.
YouTube - Rod stewart & it's the faces stay with me live uk
You can see it tucked away stage left, right behind him. 0:56 & 1:36 into the video.
Then look at cleans,
Ole Jeff Beck is using tiny amps on tour right now with Imelda May.
YouTube - Jeff Beck with Imelda May-Tiger Rag (Based on a 1917 song by the Original Dixieland Jass Band)
Did the same thing on the Les Paul Tribute
YouTube - Jeff Beck honors Les Paul [Best of Guitar-Tube]
I have most of them at hand to play with.
The 5 tube design is not going well at all, and no electrcity has been applied yet. I dropped the partially assembeld perf board. The weight of the Tamura OPT broke the board in half and destroyed the OPT. Looks like I get to start over on the perf board. I need to order a new OPT. It won't be a Tamura, which wasn't part of the long term plan since they have doubled in price since I bought this one in 2005. It was $6, now it is $12. I had a good collection of potential OPT's that I tried for HiFi use 6 years ago because they were cheap. The Amveco toroid which does work good in now $22. Game over on that one. Most of the others are now too much $$$ too.
"stuff" happens. That's what I get for having a messy bench and working late at night. It was just a filament transformer being used as an OPT, but being able to claim a Tamura OPT would have been cool.
Tremolo is great if you play 60's surf music, which is what I learned to play on, but it isn't too popular today. The additional parts wouldn't see much use.
Reverb is useful. I would put it in if it would fit the price, but it doesn't. You need an additional tube, extra power to feed it, a transformer to match the tube to the reverb tank, and the tank itself. This adds $20 to $25 to the cost, minimum.
I am looking into these low cost amp designs as a platform for future addition, even if the additions are populated with sand based life forms. Tremelo is just one opamp. I really got to conquer the DSP stuff. Some chip based effects are almost believable now. Might be passable strained through a tube amp.
Fender is now selling a line of DSP based solid state amps that are programmable by a PC via USB. They also have preset "models" of vintage amps. Some are quite realistic. Of course there are no models of "cranked Marshall stack" in a Fender amp, but there is "Brutal Metal" played on a Jackson guitar. If you are not aware of the wide range of "tones" that used to be generated with minimal external effects, check these emulations out. There are about 25 sound clips on this page. Also keep in mind that ALL of these sounds are coming out of a $200 amp, and switching between these sounds is easy.
Fender Mustang Amplifier Series
http://www.mcmaster.com/#continuous-length-extension-springs/=ctgaeh Click on .012
APS4812B-LW100-R PUI Audio Speakers & Transducers
Reverb for under $8.00!
The most expensive part of tremolo is the control and knob!
APS4812B-LW100-R PUI Audio Speakers & Transducers
Reverb for under $8.00!
The most expensive part of tremolo is the control and knob!
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