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erik2A3

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  1. Yes! Thank you! It's so important. In case someone might be wondering why: One hand in a pocket helps prevent a potential charge from going through the heart - and possibly stopping it.
  2. Henry said: "First thing to check is connections, all connections tubes and input cables. Cleaning the pins of tubes and sockets is always advisable. Many different products available. Always consider connections before digging deeper or replacing tubes." Excellent advice, particularly with male tube pins. I use those green abrasive pads for the pins. SOCKETS: IF YOU OWN AND KNOW HOW TO USE A MULTI-METER, CHECK FOR RESIDUAL DC BEFORE DO ANYTHING, MAKING SURE THE AMP IS UNPLUGGED AND TURNED OFF. IF YOU DON'T KNOW HOW TO MEASURE FOR STORAGE CHARGE IN BIG CAPACITORS, LEAVE IT TO SOMEONE ELSE WHO DOES. IF THERE IS STILL DC PRESENT, DON'T TOUCH. Apologies again. Know and respect your limitations!
  3. I listened to your recording, and what I heard is very similar to dusty/dirty tube sockets. Loud cracks and pops are in my experience akin to inadequate connections, but I'm familiar with Prima Luna, and can say with confidence that soldering-related issues are, at the very least, not likely. The workmanship on Prima Luna Products, which are wired point-to-point, is among the very best available. "I doubt it is the actual sockets but anything can happen, if it is just the female part of the socket you can use small jeweler screw drivers or better a dental or mechanics pick and re-tension the sockets to fit tight again. You can also have a bad solder connection to the tube sockets that after removing and installing has altered the connection." I'm sorry, but............. ATTENTION! I have seen instances here on this forum over the past 20 years (which is when I became a member), where people with very little or absolutely no experience working with high voltage circuits have been badly shocked by either poking around inside an energized amp in order to move wires around, soldering in a live amp (an alarmingly ignorant thing to do -- even for an experienced technician, etc. I agree that tightening the female socket pins with a dental pick or similar tool might help. HOWEVER (sorry for the all-caps, but it's necessary). There is a structure in a tube referred to as the plate or anode. That is where the high voltage on a tube resides. If one happens to be using a conductive tool for pin re-tensioning, even if the component is turned off, this represents a seriously dangerous safety hazard. I've been working-on and building tube equipment for a long time, and must confess to have made stupid mistakes -- simply from being in a rush, or too confident (Lots of that here on the forum)...or careless, or whatever. I've said this over and over again here: EVEN IF A COMPONENT IS TURNED OFF AND UNPLUGGED IT IS STILL POSSIBLE TO RECEIVE A POTENTIALLY LIFE-THREATENING ELECTRICAL SHOCK FROM THE CHARGE STORED IN POWER SUPPLY FILTER CAPACITORS. IF THE POWER SUPPLY DOES NOT MAKE USE OF A BLEEDER RESISTOR ON ITS OUTPUT, WHICH WILL ALLOW CAPACITORS TO GRADUALLY RELEASE THEIR CHARGE, ONE PUTS ONESELF AT SERIOUS RISK FOR ELECTROCUTION. There is another way to quickly bleed down capacitors before doing any work, however I'm just going to leave out the details of that. Leave the work to someone who knows how to work on this stuff. So, what CAN be done in this case? With the amplifier off, try removing and reinserting each tube in its socket a few times. If the sockets have exposure to normal house dust (if they are covered or shielded), simple dirt can very often cause some of that gritty, scratchy sound in your recording. This is a problem I have frequently, despite lots of dusting, and it can help. If you have hum, that involves some extra investigation, and often depends of whether the frequency of the hum is 120Hz or 60Hz. Hoping you solve this problem, although my main concern here was not so much the noise you have, but rather wanting to once again highlight the importance of safety when working on this stuff. Passive crossovers are totally different animal. I remember once, many years ago here, when one very confident member called another equally confident member a CHICKEN (good grief) for not being willing to solder inside a tube amp while it was plugged in and powered on. The story ends with the member who owned the amp and wanted to work on it returning to the forum to share how he had gotten an absolutely enormous zap when his soldering iron accidentally touched one end of what happened to be a..... plate-load resistor. Be Careful.
  4. Captainbeefheart "they use a 1/5 watt resistor" They do? or maybe 1.5 watt?
  5. I had the chance to audition the Peach when Mark first introduced it here too many years ago. What a truly marvelous and extremely flexible line stage! My wife and I both really liked it, but were just not in the position at that time for another preamp. An outstanding component from a gifted and influential designer. And yes, RIP Dee. He was a good friend and an absolute gentleman in the truest sense of the word.
  6. I have built a couple versions of Electra-Print's DRD single-ended designs. Some of you probably remember when the 300B DRD (Direct Reactance Drive) was first published in Vacuum Tube Valley. I thought you might recall that article. Welborne Labs (whom you may also remember) began selling kit versions of the DRD amps, and I built a pair of the 300Bs, as well as the 45, for other forum members here a long time ago., Not to get Curious George's great thread off track, but just thought to share it since some different input/driver variations have been discussed here. Jack Eliano, who designed the DRD, also winds extremely well-made transformers and chokes......and they are definitely on the expensive side, but in my view well-worth the cost. I also built a pair of 2A3 mono blocks based on a parallel feed output designed by another forum member (also a long time ago), and then rebuilt it using certain elements of Eliano's DRD. I still regret having sold those amps. They were absolutely stunning, with amazing transient response, air, detail (not too much), and very decent low end reproduction. The output stage uses a very high impedance choke instead of the much, much more common grid-leak resistor; and, as also mentioned above, is significantly more expensive. But gosh, what an amazing sound. Here's the DRD schematic from the Electra-Print website - just in case you (or others) might be tempted to have a go at this very unique design. https://www.electra-print.com/300bdrd.php And the pilot light comment I made: Of course you are right. An actual lamp, as you said, is definitely much easier to see than glowing filaments. As I re-read that part of my response, it sounds sort of nit-picky. I didn't mean for it to come across that way. If it did, apologies.
  7. Nice job! The 6SL7 is a really nice tube -- along with the 5687, one of my favorite input/drivers. The 6SL7 is also great with both sections paralleled and direct-coupled to the final stage -- thus getting rid of those pesky but often necessary coupling caps. Your chassis layout is particularly well-done, with the power supply physically well isolated. Granted the rectifier's job is, depending on one's viewpoint, perhaps a bit more plebeian when compared to the signal-handling valves in the front and final stages, and is usually quite less expensive -- particularly compared those large power triodes -- but, I don't know, maybe it would have been kind of fun to have the rectifier a notch or two more visible. That octal hole behind the PT is also a good place for a large chassis-mount single or multi-section electrolytic can. Keeping 60Hz alternating current as far away from the music as possible is always paramount, and you've done a great job in that respect. PS: Tubes can also function as a pilot light! Super-clean work - lucky new owner!
  8. If this doesn't work out, I have one I will give you for free - if you'll pay shipping!
  9. Well said KT88. I can’t recall how often I’ve come across cases where blame was put...rather shallowly in my honest opinion...on a specific output (or input for that matter) device with complete disregard for the circuit in which it’s used.
  10. Good! I get it. Audio adjectives can be interpreted many different ways... Accurate Fast Warm Sweet bright muddy ...the meaning of each often different depending on the person. What's 'warm' to one person might be too 'cool' or 'bright' for someone else.
  11. So a paralleled 6N2 RC coupled to the output - I'm assuming. Great, have fun!
  12. What does ‘warmest sounding’ mean?
  13. erik2A3

    New Amp

    That's what I did to my SE 6V6 Decware Mini Torii - replacing the small OEM output transformers with much larger OPTs with UL tap.
  14. Nice! Is the SRPP driver part of your modification or the original design? CLC is definitely better if you have room! Very cool little amp! edit: And here we also have an example of elevated filaments off the voltage divider on the output of the PSU. Just curious (George!) It seems you've already achieved some great noise rejection, and wondering if you tried just grounding the filament supply center tap.
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