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Chakaranda

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  1. Pics of the amp can be seen here: "http://www.groupdiy.dk/index.php?topic=1591.0" (please let me know if you for some reason can't get to the page)...Yes it does sound "silky" and warm ___ Actually I have always been a tube-kinda-guy: I've always been using Guitar tube-amps (transistors simply don't get it right when it comes to musicality), but I never thought I could afford a real HiFi stereo tube amp...But sometimes one gets lucky: I got this X-100 for less than $100 through a friend, and the next day I was offered a The Fisher K10 Dynamic SpaceExpander for the same amount Those K10 units are extremely rare over here (Denmark, Europe) so how lucky is that ?..he he.. ...and both units in perfect shape and working condition ...So yes It's a true pleasure to step into this world of Stereo HiFi Tube gear ..Finally: Now it sounds RIGHT ...I Dont know if there are any Klipsch dealers over here ? (I'll check it out). anyway loudspeaker investments is a bit down the line: I have some amazing homebrew "studio-monitors", built by a guy who whatever he do, only do the absolute best: ..i mean; the cables are pure silver....yes pure silver! i don't know what speaker-units is in there (they're from early eighties) but they sound amazingly natural ....an oscilloscope I'll get in a future not too far away from here: but I have to prioritize and get the Fishers going first 'cause I need them urgently in the home-studio for my recording-sessions
  2. Pics of the amp can be seen here: >http://www.groupdiy.dk/index.php?topic=1591.0< (please let me know if you for some reason can't get to the page)...Yes it does sound "silky" and warm ___ Actually I have always been a tube-kinda-guy: I've always been using Guitar tube-amps (transistors simply don't get it right when it comes to musicality), but I never thought I could afford a real HiFi stereo tube amp...But sometimes one gets lucky: I got this X-100 for less than $100 through a friend, and the next day I was offered a The Fisher K10 Dynamic SpaceExpander for the same amount Those K10 units are extremely rare over here (Denmark, Europe) so how lucky is that ?..he he.. ...and both units in perfect shape and working condition ...So yes It's a true pleasure to step into this world of Stereo HiFi Tube gear ..Finally: Now it sounds RIGHT ...I Dont know if there are any Klipsch dealers over here ? (I'll check it out). anyway loudspeaker investments is a bit down the line: I have some amazing homebrew "studio-monitors", built by a guy who whatever he do, only do the absolute best: ..i mean; the cables are pure silver....yes pure silver! i don't know what speaker-units is in there (they're from early eighties) but they sound amazingly natural ....an oscilloscope I'll get in a future not too far away from here: but I have to prioritize and get the Fishers going first 'cause I need them urgently in the home-studio for my recording-sessions
  3. Hi Thanks a lot (for compliments and all) Regarding the Rectifier Tube: Ok I consider it fine then ) Regarding my guitar-amp: It was a learning by doing process (that's the only way I know)___ I don't have access to an oscilloscope: The amp is built using the cheapest DVM plus my ears as the only tools for measuring performance )) (I am a bit proud of the result; I think it sounds great (here's a sound clip http://enlightened-being.net/kingloyal.mp3 ) And thanks to AC-filtering, multiple star-grounding and shielded signal path the amp is virtually hum-free )......Regarding The Fisher and the caps: I've decided to give it the cap-job now: in total there are only 11 electrolytic caps plus a few Mylar-caps (which I'm not sure will need replacement??) so it will not be that expensive if I in the first place use a little lower quality than "handmade boutique quality" caps. Today I have measured a few caps leakages (shorts) here and there, so The Fisher is now on the workbench awaiting some fresh caps )) Once those are installed, it'll be interessting to see if the voltage readings change for the better ) ....Really looking forward to listen to music again through tubes; My old NAD 7240 are OK, but those transistors doesn't really sound _musical_ as the (telefunken) tubes does ))
  4. Thank you very much again, this really is most helpful Regarding the fan: we think alike I already planned to make such an installment in my tube amps _____ Regarding rebuilding caps: thanks again: I'll have a look at it, sounds like a very good and useable solution..__ btw do you know this site ? http://fragjanzuerst.de/eindex.htm he stocks new german produktion multicaps that (physically) fits these American amps.___...... Regarding tubes and sound: May well be you're right about the NOS Sylvania (I haven't heard them) but ... well being a musician (I'm a guitarist) i guess i have trained my ear for hearing even extremely minor nuances in sound: to my ear the differences in tube-performance (sound) are very clear and distinct. The Telefunken tubes I have are the ones i love the most (followed by Phillips miniwatts) So i want to preserve the Telefunken tubes this amp is born with as long as i can..also because NOS tubes of this (sound-)quality are getting real expensive and very hard to find.____I still have a lot to learn about tube-amps...three month ago i knew about nothing at all: one month ago i finished designing and building my first SE 5Watt Tube-amp (guitar amp) http://www.groupdiy.dk/index.php?topic=1591.0 ____ now one question is still lurking in my head: when a rectifier tube is about to wear out; could the first signs be that the DC output voltage raises? or would it lower ?
  5. Thank you very much for the link ....very informative... well yes maybe I worry to much about my old amp..but maybe it's understandable ? : I cannot afford to replace any of the difficult/impossible-to-get vital parts such as the output transformers, or the Telefunken tubes (all in all 10 telefunken plus one mullard) in this amp; so yes I am worried that the 418 volt on the plates of the output tubes is minute by minute frying the tubes plus the output transformers....I will do a recap, but I also really want to learn how test if they're OK or not, and get to know this amp in depth ___ btw: it's not that easy to find replacements for the big multicell electrolytic caps (cans) ....
  6. Thanks...wow that's was a lot of Fishers anyway: Today I've got hold of the correct original schematic and service manual: The value of the two resistors in question are the correct values and it seems that there's no major problems: my readings of voltages are more or less exact on the spot and any case no more than 10% above or below what the schematic says.____ the heater supply is a little low (5.8vac) and the AC on pin 2 and 8 on the rectifier is 4.5v (should be 5vac) But I don't think that's any major problem ...or ?____ Bias is also fine (after adjustment!) +44vdc on pin nr. 3 on the output tubes.______I've read somewhere that back then they measured using tube-equipment that had some resistance per volt ..i.ex. 1Kohm per volt...if that's true ? (can anybody confirm this?) well if so, then that might be the reason why I get a little higher readings on the high voltages..... _______However I'm still a bit concerned that the DCvoltage on the plate of the output tubes is above 400vdc ..it is 418 ...seems a bit high doesn't it?
  7. I live in Copenhagen Denmark (northern part of Europe) The resistors are for sure original installed parts, and I'm sure they are installed in parallel: it's not "rocket science" to see that: the amp is point-to-point wired the measuring confirms the value: i get 65ohm measured across ..close enough____ I'm sorry can't add a picture of the parts in question: if you could see what i see, you would agree ______ anyway maybe this is a possible explanation why i get somewhat higher measures than stated in the Schematics: just read this note in the schematics: "DC voltages measured with vaccum tube voltmeter AC voltages is measured using a 1000ohm per volt voltmeter" !!____ That would explain a lot, since I'm using a modern multimeter! and further on: Nominal tolerances in components makes possible a +- 15% variation voltage and resistor readings" ______ I'm starting to suspect that this particular X-100 is a variant from the one in the schematic I have: the schematic operates with EL84 output tubes: but this amp might well be born with the 7189a type tubes, and therefor adjusted accordingly to the higher ratings of a 7189 ! that would explain the difference in the value of parallel resistors installed compared to the values in the schematic....anyway since the schematic says that +-15% is normal tolerance this amp is more or less within specs.
  8. Thanks for your answer, but please read my first post more carefully (since the AC output from the PT is at the specified 360 then the following DC voltage readings _after the rectifier_ should likewise be within the specified range ...but they are around 20vdc higher than they should be, as you can see first post) The resistors are connected in parallel...I do know the difference
  9. Hi I have recently got a Fisher X-100 in perfect shape and all parts original It has been playing absolutely perfect for the few days I have owned it Today I decided to open it up, clean the jacks and tube-pins and check the bias: The voltage on pin 2 of the output tubes was around 25v and on pin three 48v !! (should be 30v and 40 v = a ratio of 3/4 according to the schematic ) I then checked the voltages around the rectifier tube (5AR4/GZ34) : 357vac comming in (fine) and 427vdc out ! According to the schematic the DC voltage leaving the Rectifier should be 410 ? I'm new to this: could it be that the internal resistance of the rectifier has dropped over the years and many many hours of use? (So that it now puts out more voltage than it should?) next I checked the voltage after the two parrallel resistors (connected between the DC outlet of the rectifier and the first cap) it is 417 ! ! it should be 390 according to the schematic Also these two resistors is of a lower value than stated in the schematic: the schematic says 250ohm but the value printet on the resistors says 125ohm I'm pretty sure they are the original resistors mounted by the factory, but why this change ? any help is very much appreciated
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