T2K Posted March 4, 2004 Share Posted March 4, 2004 How long should a tube integrated be allowed to warm up before setting bias? Will/should the reading change if set at say 30 minutes, then after 2 hours? Just wondering. And thanks. Keith Quote Link to comment Share on other sites More sharing options...
Deang Posted March 4, 2004 Share Posted March 4, 2004 10 minutes Quote Link to comment Share on other sites More sharing options...
BackBurner Posted March 4, 2004 Share Posted March 4, 2004 Can't remember the last time i shut them off ? Keeps my bedroom cozy at night Quote Link to comment Share on other sites More sharing options...
tubeglow Posted March 6, 2004 Share Posted March 6, 2004 T2K, A really nice way to bias your tubes that was taught to me by an old tube master (my dad) many years ago and still seems very effective...let your amp settle in for about 10 minutes after turning on...bias the tubes to 10-15% BELOW desired mV level (e.g. 40mV target=32-36mV initial bias)...let settle in (another 10 min.) and re-bias to the recomended mV level. I have found that tubes tend to stay biased the longest using this method. Hope this helps, Mark. Quote Link to comment Share on other sites More sharing options...
DRBILL Posted March 6, 2004 Share Posted March 6, 2004 Mark is on the dot. I couldn't have said it better. I wonder if I knew his Dad?! Father Bill+ Quote Link to comment Share on other sites More sharing options...
T2K Posted March 6, 2004 Author Share Posted March 6, 2004 ---------------- On 3/6/2004 5:51:57 PM tubeglow wrote: T2K, A really nice way to bias your tubes that was taught to me by an old tube master (my dad) many years ago and still seems very effective...let your amp settle in for about 10 minutes after turning on...bias the tubes to 10-15% BELOW desired mV level (e.g. 40mV target=32-36mV initial bias)...let settle in (another 10 min.) and re-bias to the recomended mV level. I have found that tubes tend to stay biased the longest using this method. Hope this helps, Mark. ---------------- Thanks for the post Mark. Sounds reasonable. Also generally reflects the settings I have encountered setting bias on my amp. IOW, bias reading down about 10% after 10 minute warmup, then slowly rises to desired setting. I'll use your Dad's handy tip soon. Thanks again. Keith Quote Link to comment Share on other sites More sharing options...
NOSValves Posted March 6, 2004 Share Posted March 6, 2004 The important thing is what is bias at when the amp is completely warmed up ? The bias varies until the amp is completely warmed up. I generally do my final adjustment on my own amp after they have been on all day. Another valid concern is with brand new tubes they will vary for the first few weeks of use and should be checked until they have stabilized. Craig Quote Link to comment Share on other sites More sharing options...
T2K Posted March 7, 2004 Author Share Posted March 7, 2004 After about 10 minutes the reading is 386 mV and slowly rises to a dead 400/399 mV, which is as close as I can get it. Checked after 3 hours and again after about 6 hours and the reading is stable at the latter figure. Keith Quote Link to comment Share on other sites More sharing options...
T2K Posted March 7, 2004 Author Share Posted March 7, 2004 Thanks for all the replys. It's stable all right Ryan. I've checked it several times and after several hours the setting is dead on. Totally quiet too. The thing sounds great, although I haven't yet decided just how it does sound to my ears. Works well with the Chorus II's though. Thanks for the great work on the restoration. Also, the 222-C that Craig restored is a great package too. I have grown accoustomed to the sound of the 222-C and when I hear it I get this warm fuzzy feeling, like being back home. Just the sound that I like, although it appears that the 233 will give it a run for the money. We'll see. Keith Quote Link to comment Share on other sites More sharing options...
Piranha Posted March 8, 2004 Share Posted March 8, 2004 Sounds like you have two great amps. Congratulations! Quote Link to comment Share on other sites More sharing options...
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