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Everything posted by dbreslauer

  1. In tube amps, the standby switch physically interrupts the B+ (DC) voltage from the rest of the circuit, between the rectifier and the power filter capacitors: essentially blocking the high voltage DC from the rest of the amp stages. When powering up an amp with standby on, the lower "heater" voltage warms up the tubes, without that high DC voltage also present. And, just a warning I feel compelled to make: Even when the standby is ON, power filter caps can hold a high voltage charge, for a very long time. do not interpret standby ON as DC not present! Actually, don't interpret an unplugged and turned OFF amp as not having a DC Charge for that matter. hope this helps! Don
  2. Awesome, congratulations! Don
  3. i don't rely on the polytuning either: a quick check/tweak of each string individually, followed by a quick strum to see how the strings line up in poly, and i'm done. works very well. Don
  4. so far so good. I primarily use Logic Pro on a mac. I found this while looking for a versatile, cheap multi-interface: this one has 8 in/4 out, phantom power, MIDI in/out: it covers all my needs and only uses one USB port in the process. And right now, the 8 input US-800 is half the price of the 6 in version US-600... I couldn't resist!
  5. Heads up, anyone looking for a USB recording interface. MF has the Tascam US-800 for $100. http://www.musiciansfriend.com/pro-audio/tascam-us-800-usb-audio-midi-interface I bought one, thought I'd share the find... Don
  6. Wow, neat page! I think I'm gonna build one of these this weekend, pretty sure I already have all the parts, Thanks!
  7. you could convert your valve junior into a "Baby Will." i've heard GREAT things about this, and the board is not very expensive either... seems like it might be a fun project too! guitaramplifierpcbs.com
  8. IMO: this is proof that tone is in the fingers and head, not the wood and wire... That guitar has always looked like junk to me. EVH could make anything sound good.
  9. Another good choice, albeit a little more money, is a Fender Super Champ XD.
  10. I put a little '59 in a tele for a friend, and its OK, a little thin when tapped IMO. But i would highly recommend giving it some time as it is: you may be pleasantly surprised with it. my own Tele has the original pickups in it: i like the diversity it offers me (plus i have other guitars that cover the sonic bases, so to speak.) any pictures? Don
  11. yes, especially with both the normal and bright volumes cascaded and dimed. I think shielding the lead to the Master Volume made the biggest impact, as it runs straight across the top of the circuit. I did the input lead to the cascade switch mainly because it's perpendicular to all the other wiring. I also braided the runs to the T, M and B pots, and shortened up pretty much every wire i could possibly cut...
  12. I sourced everything separately for this build, right down to staking all the turrets (all part of the fun ), but I believe both Trinity and Brown Note have kits for an "18 Watt Plexi", which would be similar. The info for this particular layout can be found at 18Watt.com, Richard Johnson did the design/mods I followed. I really like the way this one is turning out! Don
  13. update on the 18W i'm building. if you're thinking of building an amp, consider this one... after my troubleshooting and testing. i changed all of the input leads to shielded wire, and cleaned up lead dress. made some other changes: higher watt resistors, cathode cap, grid resistors, etc. i bought an unloaded 2x12 speaker cabinet used for $50, and put both greenback and 30th anniversary celestions in it. here's the sketch of the head cab in planning: i will get some sound clips together soon. the cascaded channels in particular are KILLER.
  14. Hey, wasn't the very first Marshall a reverse engineering of the Fender Bassman? At the time, American valve amps were either very expensive or hard to come by in the UK, and Jim Marshall saw an opportunity. smart guy!
  15. to me, "boutique" implies a low count, custom made item. this term is used with amps and pedals a lot of late. "Plexi" describes the appearance of some early Marshall Amps, which had a plexiglass faceplate. The name has become synonymous with the amp construction, even though it technically has nothing to do with the amp's function. These were all valve amps at the time though. Modeling adds the prospect of digitally synthesized tones, and can sit on top of either Solid State (think Fender G-DEC) or Tube (think Line6 Spider Valve) power amps. There's a whole universe to be discovered inside the workings of an amp: solid state vs. tube recitification, hybrids (a tube pre-amp feeding a solid state power amp), and so on. The choices are amazing, we live in good times. have fun! Don
  16. it lives! there was a small error on the layout i used, and fixing that i now have a very LOUD amp. Fortunately i also posted on an 18 Watt forum and someone was able to help me: the connection i needed to fix was on the bottom of the board, and i'd made that connection over a year ago. i was really starting to lose my mind! :) now, to the fine tuning: the gain on this thing is crazy, and the master volume is not subtle enough for my tastes: time to tweak! oh yeah, and i gotta get around to making a box for it too. Don
  17. I drive back to NJ from Chicago at least twice a year to see family: it's ~12 hours, with a head-messing time zone change in Indiana (worse coming home than going out.) Also, I imagine in PA, Route 80 is far more interesting: the mountains are breathtaking, esp. in the fall. it's only 12 hours, just two tanks of gas and i'm there. have a safe trip!
  18. Hey Andy, that's beautiful! are thos NOS mustards? I had a similar issue with heater wiring with the first champ amp I built, so when doing this one I actually checked continuity while hooking them up. I know exactly what you mean. For first power-up, i always follow this checklist document at Paul Ruby Amps. (It's a very good idea to never assume when working with these things...) http://paulrubyamps.com/info.html#FirstPowerUp you can't see it in the previous pics, but I have a ground lug right by the dual cap, and then one right below the input jack. i've read that its good to ground right after the input to also help with hum and the such. The power up went well, and all my voltages are all good. For this amp I have to use a "vintage voltage adapter" box to pull my house current down a bit though. this neat gizmo drops my house voltage by -6 and -12: the PT in this amp wants 110V in... I'm debugging the amp now: only getting very low sound at the moment (other than hiss, which leads me to believe my problem is either with my input, preamp or PI.) I get a nice loud pop reading DC off of the PI at pin 7, so i think the OT and power sections are ok. This amp is an "18W Plexi", with the normal 18W style power section (EL84), but a JCM800 style tone and preamp setup. I can't wait to actually HEAR the thing. debugging sucks. here's a pic with all the valves in: thanks!!! Don
  19. thanks! i am powering it up w/tubes out tonight, to make sure it doesn't burn up and to measure some voltages. then i'll put in some tubes and hook up some speakers (if all goes well) then comes the really un-fun part: making a cabinet for it. lol! Don
  20. all wiring done! this is the top of the amp:
  21. transformers, sockets and inputs all wired. next up are the controls. then, on to voltage testing.
  22. ugly wiring? lol, that's beautiful! my amp is quickly becoming ungainly in the wiring dept, but i am doing my best to keep the leads as short as possible, and the joints as clean as possible. i've also been carefully checking connections with my meter along the way. i've yet to build an amp that's worked perfectly from first power-on, but i've been fortunate that my mistakes have been relatively easy to discover. i hope this one's the same... Don
  23. thanks! it's a lot of fun once you get going. i've been meaning to finish this one for a while, and now i'm inspired. Don
  24. doing the heater wires on my 18W today. the ball should start rolling faster, now that i finally finished cutting all the holes in this chassis. (a pain!) i hope to have this head finished in the next week or so, as i still have to make a 2x12 for it too.
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