"Warming up" Tube amps? - Page 3

I let my amps warm up for only a couple of minutes before listening at low to moderate volume. I've been doing this since the late 60's without problems with several different amplifiers I've owned It's true tubes need 20 or more minutes to sound their best, but as far as damaging affects, I highly doubt it as long as you keep the volume within a reasonable level until fully warmed.

I've got a MAD Ear+ HD Super on order, which uses "soft-start tube rectification", any thought on what that means with regards to warm-up, switching headphones with the unit powered, etc.?

I only give my tubes a couple minutes of warmup before i start playing music... but don't get into the serious listening for 15-20 minutes...

Cheers,

You can always modify an amp to put the filaments on their own switch. It's relatively simple and will let you warm them before applying a signal. You can also add a circuit that will bring up the filaments slowly.

Tube amps do not all behave the same when you turn them on. For one, tube rectifiers, by their nature, bring up the other tubes slowly and gently. Another consideration is how the filaments are run. Some amps run the filaments right off AC from the filament transformer. Instant AC on hits fairly hard. Some filaments are run off DC, sometimes nicely regulated DC, even, which is a gentler way to bring them up.

The fact is that the more an amp costs, the more likely it is to have better tube protection built in. That takes money, engineering and labor to put in. Not all expensive amps are carefully built, but all carefully built amps are expensive. There's no shortcut around that. Most of the inexpensive amps lack these features - the typical owner is sold on the low price, attractiveness of the case and tuberolling options. None of those are relevant to performance. It is worth paying more to have a well made amp that takes care of these details. That, and a good power supply. I won't go into that here, but the quality of the transformers and circuit design trump the variety of tubes you can put in it.

Another factor for tube life is how hard the tubes are driven. If you look at tube curves, you'll see the response curves given the voltages the tube is run at. There's no one set point. You can run (for example) one at 300V or at 400V. Either point will give you a unique response curve. If you run too little, it'll go non-linear, same with too much. There's a balancing act where you decide where to run them.

What I'm getting at is that if the designer runs the tubes on the "hot" side, it'll detract from tube life. Going hotter can produce more power, maybe a more appealing response curve, etc. that might have sonic benefits. However, that shortens tube life. A more conservative setting can prolong tube life.

So there's more to this than warmup, how the filaments are run, and other considerations that have been brought up here.

^^^ Totally agree, especially on the issues of powering up the amplifier, AC transients can have huge in rush spikes and have a large impact on the tubes. That's why I have employed "Soft Start" circuitry on most of my 3-500Z HF Linear Amplifiers for ham radios.

Warming up is fun because it builds the anticipation of the lush tube love baby.

On "Soft Start" circuitry for example the Little Country III 6922 Tube Headphone Amp also incorpoates a soft start circuit to prevent a rush of current to the tubes on power up. The designers have put some thought into the power supply circuitry for this amp.

Another example is the Bada DC-222 vacuum tube hybrid integrated amplifier which has also employed "Soft Start" circuitry.

I generally power up the amp half an hour prior to serious listening.

Yeah, 20-25 min usually, for me.

Ditto my G&WT2.6F...the little blue led blinks for about a minute before the amp comes on