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The "Smoke Screamer" Tube Amp

After building the "One Puff" all tube cigar box combo amp I started thinking about a more compact and powerful design. I came up with a new design called the "Smoke Screen". It is louder, cheaper and easier to build. Since this amp only uses one (ECL85) tube it is more compact and easier to "stuff" into a cigar box. It produces a little over 3 watts and sounds amazing. Not a high gain amp but can easily get nice overdriven tones with higher output pickups. It is much louder than the One Puff. Put a pedal in front of it for mega distortion or other effects. I have a working prototype and I am still tweaking the bias and plate voltage settings to get the best possible sound. Schematic, parts list and demo MP3 coming soon.

Would there be any interest in a parts kit? Probably in the $80 price range? Maybe some A La Carte options for the box and speaker?

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Replies to This Discussion

Permalink Reply by BLY on April 27, 2011 at 1:31pm

Smoke Screamer sound demo. Some clean and over driven sounds. Finger picked with glass slide. No processing. External 10 inch vintage Jensen alnico speaker. Close miced with large element condenser mic.

Attachments:

ss1.mp3, 2.2 MB

Permalink Reply by Jon Pruett on April 28, 2011 at 5:47am

I'm definitely interested - I've been looking for a simplified tube build for a while and this sounds great!

Permalink Reply by BLY on April 28, 2011 at 7:58am

Hi Jon, I posted the schematic and parts list earlier in this thread. It's a pretty simple build if you have built a tube amp before If not, I will be building a few to sell soon. I just dont have the time to kit this amp right now.

Permalink Reply by Jon Pruett on April 28, 2011 at 9:08am

I haven't built a tube one yet (several other opamp projects under my belt though). I'm happy to support folks making a few bucks if you have time to source the parts and assemble a kit, but no stress if you're busy. I have one of those 10 pound Mouser catalogs sitting around here somewhere... :)

Thanks!

Permalink Reply by BLY on April 28, 2011 at 11:24am

The parts are already sourced for you on the parts list. This will not be a step by step instructional type kit. Just parts and a schematic and a few build notes. Just like the Weber kits. They assume the builder has done it before. I will happy to help someone as much as I can though. Just real tight on time right now.

Permalink Reply by BLY on May 6, 2011 at 8:13am

Rev. B Update: I reworked the power supply for much lower noise and hum levels. Noise and hum is virtually inaudible now. I tracked down and eliminated some minor parasitic oscillations and noise by adding foil lining to inside of box and grounding the foil. Further hum reduction by relocating the output transformer to front of the box. Added a very handy line out circuit. Please use Rev. B schematic for all builds. Thanks -BLY

Permalink Reply by BLY on May 6, 2011 at 8:34am

Smoke Screamer Rev. B Schematic

Attachments:

Smoke_Screamer_Tube_Amp.ps, 24 KB

Permalink Reply by Bill Harbour on May 10, 2011 at 1:58am

What program do I use to open up the .ps file??

Permalink Reply by Bill Harbour on May 10, 2011 at 2:02am

Here's a little amp that I designed that uses an LND150 mosfet as a preamp and an EL84 output tube for about 5 watts output power. The LND150 runs on the high voltage B+ power supply just as a tube would do. This is a very simple amp build too. Both the Smoke Screamer and One Puff are very cool amps!

Permalink Reply by BLY on May 10, 2011 at 5:11am

Thanks Bill. The .ps files can be opened with Adobe Acrobat. I attached it to this post as a pdf. I took a look at your amp and it looks like an interesting design as well. My one puff design originally used a j-fet preamp. Mosfets and J-FETS both sound allot like tubes. I just put together a stereo version of the Smoke Screamer geared for hi-fi use. Mounted on a real nice big Nat Sherman Suave box. I used the Russian equivalent tubes 6F5P. Very cheap tube at $1.75 each ! Some people in the hifi world call them the "poor mans" 2A3. They have a higher gain factor of 70 which gives more overdrive. Not that I need more overdrive in a hi-fi amp but in the guitar amp version it really helps.

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