ben. Posted December 22, 2006 Share Posted December 22, 2006 OK. The thingy should have a dial of some kind. Find where it says numbers somewhere around 100-150 and letters like V and AC. That's where your thingy or "meter" diplays measurements of typical household electricity supply. Stick the pointy things in the vertical slots in the wall socket. Don't touch anything metal. If it doesn't read 120 call Craig at home. He's prolly up... Quote Link to comment Share on other sites More sharing options...
maxg Posted December 22, 2006 Share Posted December 22, 2006 Not dissimilar problems over here too. Voltage swings from 218 to 234 and frequency from 46 to about 54 that I have seen. I run 2 boxes to fix the problem with the system - one for the voltage swings and one for the frequency. I have no idea which is the more important for most equipment but for the TT the frequency is definitely the key. The nice thing about these digital amps is that they seem to be much more tolerant of voltage and frequency changes than either tubes or SS amps. I run the amp directly from the mains - bypassing both boxes and even when the lights go dim the music quality does not seem to change. When I ran my tube amp direct I used to burn a KT88 or 2 every six months - although the EL34's faired rather better. Not sure if that was due to the make or the power or both. For reference the KT88's were JJ Electronics (Tesla clones) and the EL34's were Electro Harmonix. Quote Link to comment Share on other sites More sharing options...
meagain Posted December 22, 2006 Share Posted December 22, 2006 Thanks Ben There's only a few things in life I fear.... falling from cliffs/heights, drowning in a car, being buried alive, and electricity. I figure the latter is all around me so it gives me a better chance at death. Measure twice, cut once. Anyway, I had a similar situation to Deans. I was turning them off religiously for a few months at the beginning, then slipped, then blew 3 fuses upon turn-on so I feared turning off/on so I tended to leave them on. I'm quite sure my electricity is wacked since electricians have done things like shaken their heads or said "wow" upon visit. Question.... I put a gadget on everything I think similar but very low end and upon removeal recently, I had to rebias the amps lower. Like, the gadget sucked away some juice. Is that typical with these things or an indication of an anomaly. Dean - about how much does this thing cost? Quote Link to comment Share on other sites More sharing options...
Deang Posted December 22, 2006 Author Share Posted December 22, 2006 There's only a few things in life I fear.... falling from cliffs/heights, drowning in a car, being buried alive, and electricity. I figure the latter is all around me so it gives me a better chance at death. Measure twice, cut once. Wow, we have a lot in common. I fear falling up the stairs, drowning in a toilet, being buried while I'm dead -- and electricity. A little over $400 from Partsexpress: http://www.partsexpress.com/pe/pshowdetl.cfm?Partnumber=248-756 I don't know Mark. I've had similiar problems with every tube amp I've ever owned save one (AE-25 Superamp). Three in particular gave me real fits -- Canary, QUAD, and VAC. Both the Canary and QUAD kept burning through bias resistors, and the VAC cooked up $500 worth of tubes after about 5 months. Quote Link to comment Share on other sites More sharing options...
DrWho Posted December 22, 2006 Share Posted December 22, 2006 ah, sounds like yet even more reasons tubes are better than SS [Y][A] I'll go sit in the corner now... [][] Quote Link to comment Share on other sites More sharing options...
Deang Posted December 22, 2006 Author Share Posted December 22, 2006 There are plenty of good reasons not to use tubes but none of them have to do with sound. Quote Link to comment Share on other sites More sharing options...
frankphess Posted December 22, 2006 Share Posted December 22, 2006 While I can not say it has made a dramatic improvement, I too recently purchased a Furman "AC Conditioner" for surge suppression and piece of mind. It does however, have 2 cool lights which pull out to shine on the Peach. http://www.furmansound.com/products/consumer/elite/elite15pf.php?req=es Quote Link to comment Share on other sites More sharing options...
NOSValves Posted December 22, 2006 Share Posted December 22, 2006 Yup wall voltage fluctuations have existed since the invention of AC!! But back in the 50's and 60's these fluctuation were more the in the 105 to 120 VAC range as the norm, today its more in the 120 to 130V range. When you have some 800 amps vintage and new in the field you soon learn that it is an issue today that needs to be addressed one way or the other. I know this to be absolutely true since my grand father retired from Detroit Edison and my own father worked for DE for 10 years in the late 50's and 60's. They would often laugh about some houses where some electronics just refused to work properly from low wall voltage. Rarely was to high a wall voltage an issue. Tubes have always failed! Why else back the 40's 50's and 60's could you buy tubes at every drug store and every single field technician carried a tube caddy with a full compliment of every commonly used tube under the sun including common "output tubes". I'm sure the drug stores would not stock tubes and the tech's would not carry them if they were the last thing on earth that failed in the gear that used them. Then factor in that most folks back then did not run the gear 24/7 or even remotely as much as most people do today. It's a different world in tube audio today then the 50's and 60's in all respects. Heck the AKfest I do every spring the wall voltage in that building drops to 103 VAC when all the systems are lit up. Seems like were back in the stone ages!! I bump that wall voltage back up to 120V to get my system to sound as I intended it to sound. Craig Quote Link to comment Share on other sites More sharing options...
Piranha Posted December 22, 2006 Share Posted December 22, 2006 This country is becoming less and less free if you ask me. A good enough reason to switch political party affiliations. [] Quote Link to comment Share on other sites More sharing options...
meagain Posted December 22, 2006 Share Posted December 22, 2006 There are plenty of good reasons not to use tubes but none of them have to do with sound. I'm not convinced. SS is going to get really good really quick - then everything will be on computers anyway SOON, and yes, it'll sound good. I wanna good DAC! Quote Link to comment Share on other sites More sharing options...
NOSValves Posted December 22, 2006 Share Posted December 22, 2006 There are plenty of good reasons not to use tubes but none of them have to do with sound. I'm not convinced. SS is going to get really good really quick - then everything will be on computers anyway SOON, and yes, it'll sound good. I wanna good DAC! Hilarous. Many a folk could be quoted saying the exact same thing in about 1967 or so LMAO!!!!!!!! History just keep repeating itself. Quote Link to comment Share on other sites More sharing options...
maxg Posted December 22, 2006 Share Posted December 22, 2006 Power fluctuation has existed since before tube amplifiers. People were not burning out tubes then at these fast rates. Also Max, were checking your actual tube BIAS or just the wall voltage? When I bought the amps the maker was kind enough to take me through the whole biasing thing with a little meter and all that. All I did was once every couple of months or so - pull the amps out - open them - insert the prongs in the right place - and bias till the meter was pointing at the same number for each tube (the number he provided). Between biasing sessions - I had one tube go Nova in a big way - amp started screaming and the tube glowed like an exploding star. I killed the power immediately and took the amp back to be checked over - lots of wires had stated to melt inside and were all replaced. This only happened once - with the JJ Electronics KT88. At other times I just worked on the basis that if I could not get a tube to bias properly it was a dead tube - or a dying one (as per the advice the manufacturer gave me). That was a regular occurance with the KT88's but never with the EL34's - although I got power cleaning at about the same time as the EL34's so it is hard to tell. Never ever blown an SS or digital amp - but I did pop a woofer on a Heresy 2 with a Rotel 1080. It was playing very loud at the time. Quote Link to comment Share on other sites More sharing options...
DrWho Posted December 22, 2006 Share Posted December 22, 2006 There are plenty of good reasons not to use tubes but none of them have to do with sound. bah, it has everything to do with the sound [] Quote Link to comment Share on other sites More sharing options...
NOSValves Posted December 22, 2006 Share Posted December 22, 2006 There are plenty of good reasons not to use tubes but none of them have to do with sound. bah, it has everything to do with the sound [] Yup in your case I'm sure it does. Tubes have trouble afford-ably getting to a 160db Quote Link to comment Share on other sites More sharing options...
DrWho Posted December 22, 2006 Share Posted December 22, 2006 There are plenty of good reasons not to use tubes but none of them have to do with sound. bah, it has everything to do with the sound [] Yup in your case I'm sure it does. Tubes have trouble afford-ably getting to a 160db lol, I usually listen under 70dB A-weighted [] What does listening level have to do with it anyway? Quote Link to comment Share on other sites More sharing options...
NOSValves Posted December 22, 2006 Share Posted December 22, 2006 You should go hang out in a SS thread.............and quit trolling threads you have no clue what your talking about in. In fact don't you have some books to read or something? Quote Link to comment Share on other sites More sharing options...
DrWho Posted December 22, 2006 Share Posted December 22, 2006 Nope, I'm on break for the next month. My apologies if I hit a nerve - obviously you need to lighten up as it was all meant in jest. Have a Merry Christmas. Quote Link to comment Share on other sites More sharing options...
NOSValves Posted December 22, 2006 Share Posted December 22, 2006 Okay back on the subject at hand and I will use Dean's extreme situation as an example. Did some basic measurements. VRD's in my system First my house is strumming along at 120V on the wall today Biased my amps at .70 volts or 70mA Plate voltage was 500V on the button. Plate dissipation 500V X .070 - 35 watts at idle (this happen to be perfect for a KT88 run in my topology IMHO they can take more but it will indeed lower the life span Used my variac and bump the wall voltage to 125V (this is about Dean's normal voltage when he gets home from work.) The bias jumped up to .746 (74.6mA) from the previous setup Plate voltage is now 520V 520V X .0746 = 38.792 plate dissipation ouch! Lower bias to .70 plate voltage rises slightly as it should 524V V .070 = 36.68 plate dissipation mild ouch! but livable Again used my variac to bump the voltage up to 130VAC (This is what was happening to Deans amps late at night only 1 volt higher) The bias jumped again from .70 to .745 or 74.5mA Plate voltage now 543V 543V X .0745 = 40.4535 Triple ouch !! Danger will Rogers.......... Lowered bias to .70 plate voltage again rises slightly 547V X .070= 38.29 double Ouch !!! 550V X .64 (bias) = 35.2 this would correct the output tubes plate dissipation but then the front end voltage would be way out of spec, it would not ruin the tubes but it would change the sound character of the amps as would the change in the output tube setup to bring the dissipation back in line. If Deans solution ends up working out it may be the best all around cure for his extreme situation. Even the SS gear and sources will benefit from this fix. I'm waiting to hear from Dean about what this thing does when the wall voltage is within less the 5V of the 120V spec. if it keeps regulating it to near 120V then it is indeed a great option in my opinion for anyone that has this type of a problem. This problem exists on just about ALL tube amplifiers, preamps to some degree. These magical self biasing designs suffer the same fate from high wall voltage. The only product that could possibly not be effected would have to employ a very complicated voltage regulation setup on all the different voltage taps in the power supply, heaters and the biasing scheme. I personally wouldn't want a product with such extreme measures at least tube based[] Craig PS I seen a few wanting to know what to bias KT88's at... the answer is- to many variables in the different amps to answer you all. You need to look to the manufacturer of your amp. I bet in 90% of the houses if folks measured the voltage is within tolerance for the .70 bias setting on my amps. If you have high wall voltage you need to address it for your entire audio systems health and Sonics. I have simple ways to help some in the amps but not a perfect solution like this gadget may end up being Dean had me purchase for him at a discount. Only time will tell. Quote Link to comment Share on other sites More sharing options...
meagain Posted December 22, 2006 Share Posted December 22, 2006 Who - I know you were funnin'. Question... if one is testing bias on a tube amp, and the numbers are quickly jumping around, and one knows the power tubes are kosher..... would that be reflecting variations with the power? And, I'm curious if this is normal or not? It makes me irritated when I try to bias and also worries me. I guess my main question is how 'much' should it jump around before your eyes. I'm not talking like .6 to .80. I'm talking .707 to .725. Quote Link to comment Share on other sites More sharing options...
NOSValves Posted December 22, 2006 Share Posted December 22, 2006 Lisa, Somethin fishy!!! send me your number again. Ahhh maybe its better for me to at least attempt the proceedure here on the forum. The first thing you need to do is decouple the amps from the rest of the electrical components in your system. So remember that silly craft project I had you do???? Yup the shorting plugs. Turn the amps off and let them cool for 10 minutes. While they are cooling pull the RCA interconnects from the RCA inputs on the back of the amps. Insert those shorting plugs and fire the amps up (again aftert they have cooled for 10 minutes). Now go screw around in the kitchen, bathroom or with hubby [6] for a half hour or so. Now go back and check the bias and see if its still jumping around like previously. Let me know the results and we will go on with this later. Craig Quote Link to comment Share on other sites More sharing options...
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