Jeesh, don't sound normal to me. As a preliminary suggestion, it's a good idea to turn off the amp first when shutting down. That way, if any of the other gear discharges anything weird when shutting down it's not passed along (and amplified) on its way to the speakers.
That said, your gear shouldn't be discharging anything weird while shutting down. Nor should it be screaming at you when it's on. I had a preamp that was haunted, hissed and whined and literally made the lights pulse once. Never did figure out what was up and finally replaced it (though consensus suggests a reactance/impedance issue with the amp--not that I know what that means). Maybe you caught my poltergeist? (Yes, my best guess is no help at all). |
Re the high-pitched whine, that sounds like a microphonics problem related to tubes, but I don't know your equipment well enough to know if that's a possibility--the CJ pre, perhaps? |
I have a similar, but slightly different problem. I have no sound issues when poweing off the preamp, however, when I power off my amp, regardless of whether the preamp is on or off, I get a popping sound out of one of the speakers. The amp is a levinson 331 and I don't remember it doing it when I first got it. It works just fine and sounds fine except for this powering off popping sound. Any thoughts?
- Scott |
Whyt_rabbit, have you replace the tubes and CJ preamp?
It soundeds like a tube issue to me. You have this high pitch noise after the tube warm up. |
Last night I switched speakers and the high pitched noise continued, so it definately isn't the speakers.
Additionally, I got the same "Poping Static" sound when shutting down the units with the other speakers.
This is definately a amp/pre-amp issue.
I'm getting a new set of tubes for the CJ and I'll see what difference these make in the "high pitched whine". I'm glad to hear that others think it is the tubes.
What about the shutdown noise, could this also be caused by the tubes??? |
First, leave the preamp turned off and just power/listen to the power amp. Does it make any noises after a half hour or more? Does it make noises on power on or power off? If so, it should be repaired. I've had 3 DNA-1s and none them make any such noises.
Second, if the amp behaves well, then it's the preamp.
BTW, are you confident of the connections in your DIY ICs? |
Yea, sometimes tired tubes can fart a bit (for lack of a better word) when powering down. While you're waiting for the new ones, one thing you can do to test whether it's the tubes is, to the extent that it is reliably happening in the right channel, switch the tubes between the channels in the CJ and see whether the sound jumps channels. If it does, there's your culprit. If not... (It's also might not be a bad idea, if for no other reason, to make sure the tubes are sitting right and hadn't been somehow loosened during shipment. You never know).
As for the "zipping" noise from the amp at shut-down, unless it's really aggressive I wouldn't be all that concerned. When you power down an amplifier it lets go of a lot of juice and is sometimes audible through the speakers. Usually there is an automatic muting switch that will mute the speaker taps so that you don't have to listen to this process in its full glory (or potentially damage you speakers) as the power bleeds off, but itÂ’s not unusual to get some sound at power down. Sometimes (rarely, I would guess) a muting switch can go bad, though. A batch of Bryston amps went out a while ago (one of which ended up in my living room) that had a tendency for the muting switch to fail (which mine did). It was not a subtle thing. Sounded like a significant static discharge, through both channels but entirely un-uniform, that would quickly crescendo hard and then fade off fairly raggedly (describing sounds is a bitch, no?). It was really loud and pretty much sounded like the speakers where being torn in half. Alarming. If you get the sound while powering down the amp (and while nothing else is on at all) I would guess what your hearing is something leaking through or around a muting switch that appears to be doing a better job on one channel than the other. Keep us posted. |
i recently had the same "popping" problem with my set up - plinius amp / CJ pre / cary CD / thiel 2.3...
this problem is often referred to as "motorboating" and is most likely the result of bad tubes in the pre amp (search for "motor boating" and "motorboating" in the tube section of audioasylum.com for more on this problem and possible solutions...
often times, replacing the tubes fixes the problem...i replaced my tubes, which fixed the problem for a few weeks, but then it came back. my pre amp is actually at the CJ factory now getting checked out. |
have any idea how old the tubes are? |
Well, I'm at home now and I'v had just the amp powered on for almost 1 hour (and nothing else - per Kr4 suggestion). NOTHING!! Pure silent blissful darkness.
Good, it's not the speakers and it's not the amp. That leave ole' Connie J in the hot seat on the high pitched "whinning". I'll have to get some new tubes first, but hopefully that will solve both issues.
However, I still get a "zipping" sound when I shut down the amp (with nothing else on). Could this still be caused by bad tubes even with the pre-amp powered off??
I have two distinct sounds on shut down. The amp makes a zipping sound and the pre-amp makes a "popping" sound. Each are separate sounds and independant of each other and other components or what is on or off when turning these components off. Both sounds only come out of the right channel.
I'll try to roll the tubes and see if the sounds switch sides. Stay tuned and thanks for your help so far. |
After you get the new tubes, if you still have a problem you might drop an email to Steve McCormack at SMcAudio (get the address under manufacturers. He's usually pretty generous with his time, although sometimes when he's travelling it takes a while to get a response. |
Also try swapping the ICs. And I second the suggestion to call Steve at SMc. |
as i wrote in my earlier post, i was having the same "popping" problem. i sent my CJ back to the company after changing tubes failed to solve the problem. they ran my unit for several days and didn't hear the popping noise, but then i spoke with them today, and they had heard it and were fixing it...i've only been speaking with someone in customer service, and he didn't know what the problem was, but i'll follow up and report back. i've found CJ helpful to deal with - i've had no problem getting in touch with customer service (Ed is the person i've been speaking with) and i've found him helpful and responsive. for what it's worth, i've also had excellent experiences with thiel's customer service in the past. certainly an advantage of buying from one of the smaller companies. |
Thanks everyone for all your help.
I'm still getting the "zipping" sound out of the right channel of the amp on Powerdown, no matter what I do (including the tube rolling) so I'll be calling Steve. Actually, that is one of the reason's I bought a McCormack, I saw his response to a couple of threads here and decided that I wanted equipment with a guy who took the time to answer his customers. It probably is the "mute" issue talked about above, but now I might as well upgrade if I end up shipping the unit back to him. He He He...maybe this is a blessing in disguise. I don't get the "popping" once the amp is shut down and the power drains off, if I wait a few seconds to shut down the pre-amp.
I just rolled the tubes and I'm waiting to see if that had any effect on the "Whinning". A couple were a little loose (probably from shipping) so maybe that was all it was. I'll let you know and if Ericd74 could keep me informed on his CJ i'd appreciate it. Nope, as I type this note, I can hear the "whinning" from the other room. Hope it is the tubes. Hey this new hobby of mine sure is fun!!!
Happy Listening.
P.S. I have no idea how old the tubes are (from a previous question and I have swapped out the IC's with Rat Shacks and it made no difference. |
Do you still have this amplifier? If so i know the solution. Please let me know. |
