When to power off a tube amp?

Highroller,

I don't know about your Lyr, but, a time delay mute is designed to prevent any output from the amp until it is warmed up and stable. Some tube gear will put out pretty nasty noise as it is powered up so a mute is designed to protect the speakers and your sensibilities while this is going on. The circuit does not necessarily also provide turn-on protection (soft start) for the amp itself; that is a separate feature. But, it is a good sign that the manufacturer is adding such features because soft start protection is even easier to implement.

George, what you say sounds reasonable, but I am not EE savvy. I can barely tell the difference between the front and back of the amp. :( Further, any mods to the amp's circuits will adversely affect its resale value.

My linestage and amp have a 12 volt trigger connection. The trigger starts the amp within 10 seconds or so after the linestage is turned on. I suspect this is NOT the same delay circuit you described. Instead, I think delay start-up prevents a linestage turn-on thump from causing a power surge through the amp into the speakers.

Otherwise, I think you and I are on the same page about turn-on/turn-off concerns. I'm not sure if 4 or 5 hours is a good number for my rig, but it's what I have been doing. Thank goodness I never had a Fourth of July problem with my gear -- at least not yet. Hopefully Ralph or Gary will weigh in.

Cheers,

Bruce

Al, can I assume, therefore, if one leaves their amp on unattended for even a short period of time, they could learn upon resuming their listening session that not only does their amp not work, they may be minus one or two speakers as well?? Al, there is obviously no written rule out there that I am aware of, ... but at the risk of too quick a turn-off/turn-on, what's your rule of thumb about leaving a tube amp on unattended?

Thanks

Bruce

I agree with Newbee, you do not have what most of us consider a "tube amp". Your Lyr is a tube headphone amp, which uses small signal preamp tubes, not power tubes. My tube preamp is on standby when not in use, there is always power to the tubes, unless I shut it off for extended absences or storms.

I would say that since your "amp" only uses two 6BZ7's or 6DJ8's, it is safe to leave on for an hour or so unattended. Warm up is 5-10 minutes, and you can leave the headphones plugged in when turning the "amp" off.

For my Bellari headphone amp I just leave it on all the time. Since it only uses 1 12AX7 tube I don't really mind if that tubes gets worn down since I have so many. For my Jolida 502P I turn it on and when all the EZ Bias lights turn red I'm ready to listen to music. For my other Response Audio tube monoblocks I leave it on for 45 to an hour first before listening. When I'm done I turn them all off.