The Amp Garage

My first build was a 22W 6V6 amp. When I drew the load line for the output valves, I came up with 7,600 ohms plate-to-plate. The Hammond 1650F is a perfect match. When saving weight is a consideration, I use the Eminance "Private Jack" or "Red White and Blues." Attached is my Bill of Materials. Hope...

I built a 50W version from the mdroberts1243 schematic. Only issue I had was the amp was excessively bass heavy. Great for high gain and heavy metal (my son loved it), but not the sound I was looking for. So, I decreased the bass pot to 250K and the HRM bass to 500K. Now the amp really sings! I used...

What happens when a stage hand drops an amp off the top of your speaker stack? I'm proud to say, "Nothing much!" Fabian, the guitarist for Boyce Avenue, told me the accident occurred during a set change. His amp, a 50W head, was perched 5 -6 feet high on top of the stack when it slipped through the ...

Great work! Here’s a tip heisthl shared with me. Run the plate and cathode leads of V1 and V2 together for about an inch. This improves tone and increases sustain. See yellow and blue leads in attached. Again, congrats on a very clean looking amp. Richard

My favorite for playing at home is a 22W non-HRM using 6V6's for output tubes. Great sound, and best of all I can go into the bedroom and play without pissing the wife off! Attached is my BOM. Good luck, Richard

I typically use the 290DX and 1750M from http://www.radiodaze.com/ in my builds. Great prices and free shipping! I use the 5V tap into a voltage doubler and then a 7808 voltage regulator to power the relays. This works great! Richard

I looked at the data sheets from hammond, but the difference between the normal unit and the upgraded one wasn't obvious (atleast to me).

Thanks Guys!!!!! Lastly, what is the impact of different speaker impedance on the primary. I don't understand how the assumption of speaker load is assumed by primaries of the output transformers. Eric The role of the output transformer is to "transform" the speaker impedance to the impedance requi...

Tom is spot on! If you do the math and draw the load line for a pair of 6L6's, 4200 Ohms works great. If you want to dig a little deeper into this, there is a good discussion at http://www.freewebs.com/valvewizard/index.html. The two articles on Power amps are pretty good.

I typically use the 290DX and 1750M from http://www.radiodaze.com/ in my builds. I haven't seen any conclusive information that the Mercury's sound better. If you do a search, I'm sure you'll find several threads on this topic. Cheers, Richard

dreric wrote:It drives me nuts when what I think should be a easy part to get proves to be the opposite.


Eric

Attached is my BOM. I've done a pretty exhaustive internet search to find the right parts at the best price. Good luck on your build!

On the schematic there's a jumper between the 1st and 2nd lug on the bass pot. On the tweaked layout it's not there. Who knows which is correct? On my tweaked d'lite I put the jumper in. I may try cutting it out. If you're using the tweeked d'lite schematic, keep the jumper. Other schematics (see n...

I am just about ready to start a build based on the layout and schematic below. Before I take the plunge are there any warnings, caveats, suggestions or opinions about the build? Thanks in advance. Eric Used this plan for my build and it produced a fantastic sounding amp! If you follow the schemati...

I am just about ready to start a build based on the layout and schematic below. Before I take the plunge are there any warnings, caveats, suggestions or opinions about the build? Thanks in advance. Eric Used this plan for my build and it produced a fantastic sounding amp! If you follow the schemati...

Tonegeek, Thanks for the info. I'm using the tweeked D'Lite schematic with a 1X12 cab and Eminence Private Jack speaker. Pre OD is 0.05uF and 10M. OD entrance is a 220K into a 100K trimmer. I started with 30k (wiper to GND) and gradually upped it to 40K. OD now sounds better. I'll continue to tweek ...