START UP AND SHUT DOWN SEQUENCE FOR TUBE GEAR

[HarryO]

I got into a discussion with a friend yesterday on the proper order for starting up and shutting down tube gear. He is an avid proponent of turning on his amp first and shutting it down last for the days listening.

I've been doing this differently for years and not always in the same order. I usually turn on my amps last and shut them down first. I usually fire up the CD player, Preamplifier, and then the Amp. Shutting down for the day, I usually turn off the Amp then Preamp, and then CD player. I can't remember the last time I had a problem of any kind.

Any comments or reasons for firing up or shutting down in specific order.

Thanks,

HarryO

[SilverSport]

Pre Amp on first then Amps...Amps off first then Pre Amp...for me

Bill

[colterphoto1]

Old PA addage- 'follow signal flow to make it go' that is amps LAST.

Reverse for shut down.

[JJkizak]

In the old days we just turned it on and turned it off and it didn't matter. Why should it now?

JJK

[Guest " "]

Yeah, I go along with the signal flow route on power up and reverse on power down.

[meagain]

But what is the technical reasoning for startup/shut down in a certain sequence? Why is this important, and why is it not good to do it higglety pigglety?

[Strabo]

To avoid any unwanted popping in the speakers as things are power up, amps are last on and first off.

My amp and pre are the only things powered down when not in use. CD and phono stay on 24/7 anyway.

Or, what Mark said. []

[RFP]

The reason this sequencing came about is that some preamps when turned ON/OFF would generate a large "thump" signal sending it into the power amp, and making your woofers jump or pop. With a big enough thump and a big enough power amp - -- kabloooey. By turning the amp ON last and OFF first, this scenario is avoided. Any of the old die hard tube folks still do this routineby habit.

Now, that's a fact... to which I can definitively attest! [:'(] Some time ago, I turned OFF the phono stage first, and the resulting thump instantly vaporized a plate resistor and rearranged the innards of one of the 6550s (and not in a good way) in my power amp. <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

Im much more careful now (!)[A]

Cheerz,

Rob

[lwhaples]

Turn the Dynaco's on first and off first.Always have,not sure why.Use to get the thump,until I moved the 3 MKIII's onto a shelve above the pre and have all the cables away from the cords.Maybe I'll try the pre first for a change.

Larry

[SilverSport]

I even wait a bit on shut down for them to discharge a bit (mere seconds)...or else I still get the thump...

Bill

[Old-Tube-Sound]

I turn on source on first, preamp second and amp last, I bring up the amp slowly on a variac over a minute time span to avoid the in-rush voltage that is super hard on tubes. I shut everything down in the reverse of turing it on.

[CaptnBob]

I found one of our auditorium's LaScalas with a woofer that had complete tears around the surround and about an inch out from the dust cap, and radial shatter tears coming out from the center. Evidently someone - who wisely hid his or her identity from me - had turned on the power amp first and the Radford pre-amp second.

What the guys are saying is true. Turning the amp on last and off first will preserve your system and keep those turn on and off thumps from disemboweling your speakers. Note too, some components, notably Audio Research tube preamps and Marantz 10b tuners, have a succession of turn on thumps as they warm up and stabilize.