joshnich Posted September 20, 2003 Share Posted September 20, 2003 Woke up this morning dropped a record on the TT and ....No sound!! Tried a CD and again ...NO Sound! It appears to be something with the power amp as I do get sound out of the headphone jack on the preamp for both CD and Phono. All thhe tubes are lighting up and I checked the fuses. All was well when I went to bed last night. I left the pre and power amp on as I usually do but this morning it just didnt work. I fear that the power amp is on its way to NC for a little repair. Its a hassle but not to horrible as I have a NOS VALVES 299 to take its place while its away. Any thoughts on trouble shooting would be great. Thanks in advance Josh Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted September 21, 2003 Share Posted September 21, 2003 Josh: Check all your cable (speaker and interconnect) connections carefully. Try a direct connection between your CD player and amplifier (use the remote if you have one, because it will be blastingly loud if you don't -- ironic that most of us use preamps to lower the gain rather than increase it). Bypassing the preamp may help you identify if the problem is in the preamp or amplifier. I have read more than once that it's a better practice to turn tube amplifiers off when not in use for longer periods. Vacuum tube circuitry can get quite warm, and heat is most often what causes damage to more fragile parts. I let my amplifiers warm up for 30 mins. to an hour before listening, and then turn them off before I go to bed. I was actually just reading something in Audio Express (DIY audio electronics publication)on this subject the other day. Also check your speaker connections. Remove all cable connections and then reinstall them, making sure binding posts and speakers and amplifiers are snug. Share what happens! Erik Quote Link to comment Share on other sites More sharing options...
rtaylor Posted September 21, 2003 Share Posted September 21, 2003 Does your amplifier or preamp have any output fuses or circuit breakers? Your speakers have any fuses? I'd check for fuses before tearing anything apart. Your pre doesn't have a mute or standby switch or anything like that that could be overlooked? Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted September 21, 2003 Share Posted September 21, 2003 He checked the fuses, this stated in his post. If you are not getting sound from EITHER CHANNEL than the cable problem is unlikely, for obvious reasons. This is more the quick fix for a SNGLE channel out. Although the cable question is more unlikely, this is something easy enough to check. I doubt anything would have come undone unless it's at the Cornwall binding screws end, something that can be very problematic if using even the average spade connectors. While there is nothing wrong with having screw terminals, the limiting plastic ridges DO present problems at the CW side. As stated, check all your connetions once again. Since the TT AND the CDP do provide output to the phones, then I would check the RCA between Cary pre and Rockets along with the speaker cables at the CW end. I still dont believe this is it, however. But it IS always prudent to go over your wiring. Again, wiring problems pop up as easy solutions usually with a single channel out. Do you have another preamp or amp? To very quickly isolate which is the problem, insert another preamp or amp in the equation. I would probably start with the amp first. As for running the CD player direct, this can be scary experience if you dont have a variable output and the beast runs 2v or more out. If the Rocket 88's are sensitive, be prepared to blow hearing and/or speakers. I would think twice about this unless a variable out. Do your Rocket 88 amps have a standby like most Cary gear? Tell me if you switched the standby off than on in the morning to listen. Troubleshooting from afar for a condition like this is very tough. The first thing to do is isolate the component, which many overlook. The preamp can probably still do ok with the headphones and yet have a problem with the output going to the amps. STill, I am guess it might not be the pre either. As for leaving the gear on, although heat is a concern with tube gear (especially over SS), I generally do as you are doing (this is also what Cary recommends). If away for a long period, I will power down the amps but most of the time, I leave them "on" unless not listening for several days. I find that most gear develops problems during the turn ON and turn OFF stage as the inrush of current causes more stress than the steady state ON. I leave ALL my solid state gear on such as CD players and amps. I havent turned my Cary SLP-70 preamp OFF in 10 years except when it's out of the system. I only use the standby. True, the preamp generates a lot less heat and stress, but leaving it on has produced zero problems in all the years. I just now retubed it (those RCA JAN 5692/5691 are amazing in this regard). As for amps, every problem I have ever had occurred at turn on/turn off. Think of when a lightbulb blows. Still, I would also probably turn them off is not listening for an extended period. Cary recommends leaving them on ALL weekend if around and listening but giving them breaks during the week. You could have a problem with the switch or some connection. My bet is it's something relatively simple but unless you have experience testing within, the external troubleshooting is all you can do. Many times, this does cure the ills but for some reason, I think it might be something a bit more. Give Kirk a call at Cary and see if you can get the guy to the phone. Although that can be a problem, he can be a help here at times. The only thing I dont like about Cary is the service sometimes. Unless they have changed something from the past, the gear can disappear there for too long. Do you have a good tube tech in your area? kh Quote Link to comment Share on other sites More sharing options...
NOSValves Posted September 21, 2003 Share Posted September 21, 2003 Sounds to me like the amp is getting no B+ what amp are we talking about here Rocket 88 ?? The tubes will all still light and fool you ! The heaters are what actually light on tubes . Josh you want me to give you a call and I will walk you thru a few quick checks ? Craig Quote Link to comment Share on other sites More sharing options...
lynnm Posted September 21, 2003 Share Posted September 21, 2003 Since you have a Scott available try feeding the O/P of the pre into the Scott via the Aux or Tape loop. If you get a signal to the speakers via the Scott then the problem is likely in the Rocket or its connections. Alternatively, if you get no signal then the problem is with the preamp.As Kelly rightly points out it is entirely possible for a defective preamp to be able to feed the headphone out and be unable to feed a signal to its main outputs. My suspicion is however that the cause will turn out to be something fairly simple. Just a thought - Do either the 88 or your preamp have a tape/source switch. If so make sure that it is set to source. You or a youngun could have inadvertently set it wrong Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted September 21, 2003 Share Posted September 21, 2003 Has the amp a standby switch? Guess lots of Cary products do. The standby switch is simply connected to the secondary center tap on the power transformer. If that connection is problematic, you won't get B+, as Craig says. In standby mode, the only thing getting voltage/s are the tube filaments -- that's all. So it wouldn't make any difference if you left those on for 1 hour before hitting 'operate' or 1 week. I always turn my equipment off before going to sleep, since I just think it's a safe practice to do that. That's just me, doesn't make me right! I'm just more comfortable. The center tap on a bridge rectifier is grounded, and the power switch functions to make or break that connection. You might let the amps sit for a few hours, unplug it, and turn it upside down and take the bottom plate off. If there are obvious wire problems or breakeage evident on the power switch or perhaps the center tap (red wire with yellow stripe), you probably found the problem. To trouble shoot a problem such as this, it's really much better and safer to have some technical experience so you don't zap yourself, Josh. AES seems to have had some reliability 'issues' in the past, and if they are too expensive, you may find far cheaper alternatives here on the forum. Good luck! Erik Quote Link to comment Share on other sites More sharing options...
joshnich Posted September 21, 2003 Author Share Posted September 21, 2003 Turns out that there is an output tube fuse that I could not see as it resides behind one of the transformers. That fuse was blown. In the meantime I put in another set of output tubes that I have but have never used, to see if that was the issue. I have replaced the fuse and now only one channel is working. Yikes! I am waithing for the tubes to cool down before putting the originals back in . Thanks for your help hopefully the original tubes will work ...Ill let you know! Josh Quote Link to comment Share on other sites More sharing options...
joshnich Posted September 22, 2003 Author Share Posted September 22, 2003 Hello all, Thanks again for all the info - believe you me I am such a moron ( as Craig can attest!!) on these sorts of things, every bit of info helps. I spoke with Dennis Had at Cary and explained the problem. He was very very helpful and somewhat flummoxed at the issue. He suggested that before we go any further that I switch both the output and input tubes by channel to ensure that is not the issue. I plan on doing so this evening. Hopefully its just a tube! Wish me luck. Thanks again Josh Quote Link to comment Share on other sites More sharing options...
Randy Bey Posted September 22, 2003 Share Posted September 22, 2003 I wish you luck. Cary has the worst freein' customer service this side of Hades. Give Dennis my best, the SOB. Quote Link to comment Share on other sites More sharing options...
NOSValves Posted September 22, 2003 Share Posted September 22, 2003 Man o man randy kind of harsh !! Josh I would never call you anything of the sort ! Like I said if you get stumped shoot me a email and I'll give you a jingle. Craig Quote Link to comment Share on other sites More sharing options...
joshnich Posted September 22, 2003 Author Share Posted September 22, 2003 Thanks Craig, We"ll keep the tube biasing escapade to ourselves!! I will certainly take you up on your kind offer once I exhaust my own feeble attempts. I am kind of on a mission to solve it myself...you know the feeling of accomplishment and all that! Josh Quote Link to comment Share on other sites More sharing options...
rtaylor Posted September 22, 2003 Share Posted September 22, 2003 1)Thanks Kelley, guess maybe the output fuses were not checked the first time around? Easy enough to miss since the power fuse was good. 2)Not being familiar with the equipment was just going thru the standard rundown for possible cheap fixes. Still wonder if there is not a fuse in the one speaker blown. Since one channel is working now have you switched speaker wires around to see if this would be the problem? 3)Are you sure the other output fuse is not blown, I've seen fuses that look good but are not, worth a look. Sorry for stating the obvious, Randy Quote Link to comment Share on other sites More sharing options...
joshnich Posted September 23, 2003 Author Share Posted September 23, 2003 ---------------- On 9/22/2003 5:15:31 PM rtaylor wrote: 1)Thanks Kelley, guess maybe the output fuses were not checked the first time around? Easy enough to miss since the power fuse was good. 2)Not being familiar with the equipment was just going thru the standard rundown for possible cheap fixes. Still wonder if there is not a fuse in the one speaker blown. Since one channel is working now have you switched speaker wires around to see if this would be the problem? 3)Are you sure the other output fuse is not blown, I've seen fuses that look good but are not, worth a look. Sorry for stating the obvious, Randy ---------------- Thanks Randy, Yes it was easy to miss the obvious! But for me nothing is obvious. Anyway I tried switching trading the output tubes by channel and the input tubes as well. Still no luck - one channel remains dead. So I spoke with Kirk at Cary and he believes it to be a blown resister. He believes that one of the output tubes failed and that the resister before the tube output fuse is also tweaked. He gave me the option of sending the amp to them to fix or send me a replacement resister to have someone install or do myself. It sounds like a pretty easy task so Ill practice my soldering skills ( last tested building radio kits and slot cars 35 years ago ) and give it a go! Josh BTW I have found Cary to be super responsive and think that their customer service has been beyond stellar! Quote Link to comment Share on other sites More sharing options...
LarryC Posted September 23, 2003 Share Posted September 23, 2003 Forgive me for being simple-minded (hey, it's my speed), but did you unplug the headphone jack? Quote Link to comment Share on other sites More sharing options...
joshnich Posted September 23, 2003 Author Share Posted September 23, 2003 ---------------- On 9/23/2003 3:45:05 PM larryclare wrote: Forgive me for being simple-minded (hey, it's my speed), but did you unplug the headphone jack? ---------------- The headphone jack is in the preamp and I only used it to check if the issue was the preamp. I have since hooked the power amp up to another preamp with the same results. Thanks josh Quote Link to comment Share on other sites More sharing options...
Randy Bey Posted September 23, 2003 Share Posted September 23, 2003 BTW I have found Cary to be super responsive and think that their customer service has been beyond stellar! yeah, well, I suppose if you get lots of their equipment and are constantly getting it fixed then you will have such a high opinion. As far as I'm concerned they're all a bunch of posers. Quote Link to comment Share on other sites More sharing options...
mobile homeless Posted September 23, 2003 Share Posted September 23, 2003 Randy, dont rag on Cary that hard just because of that prototype preamp you got. It was a used buy of AudiogoN, shouldnt have ever been in the used market in that state, and was probably a nightmare for Dennis and company to mess with. Indeed, it was probably one of Kirk's experiments that he sold to someone. Granted, Cary has pissed me off in the past but I got even with the loons, a story I will share sometime. But if you go and meet them in person, they are pretty nice freaks. Also, I think your experience would have been totally different if the piece was actually a legitimate preamp and not a one off prototype. I have seen almost ALL the versions of Cary preamps and that was a mutant combination. Still, I bet if it could have been made to work, it would have been a nice unit. Sending you mail. kh Quote Link to comment Share on other sites More sharing options...
joshnich Posted September 23, 2003 Author Share Posted September 23, 2003 ---------------- On 9/23/2003 4:31:34 PM Randy Bey wrote: BTW I have found Cary to be super responsive and think that their customer service has been beyond stellar! yeah, well, I suppose if you get lots of their equipment and are constantly getting it fixed then you will have such a high opinion. As far as I'm concerned they're all a bunch of posers. ---------------- I am not sure if a pre amp and a power amp would qualify as "lots of equipment". In fact the Rocket 88 was purchased used (from a forum member), a fact which has not deterred them from giving me all the time and service that one would have expected from a recent "new purchaser". It is also not accurate to say that my Cary equipment has had to be fixed lots of times, unless once counts as a lot. I am not discounting your experience, only reporting on my experience. IMO if more companies treated folks the way I have been treated by Cary the world would be fine place indeed! Josh Quote Link to comment Share on other sites More sharing options...
NOSValves Posted September 23, 2003 Share Posted September 23, 2003 Josh, Did you have any luck ? Craig Quote Link to comment Share on other sites More sharing options...
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