Breaking in equipment...ie Amps

[Wheelinarcher]

After a decade hiatus, I am getting back into home theater and great audio equipment. I recently purchased a Yamaha MX-A5000 amp and matching pre-amp. I heard somewhere were you should leave the amp on for 72 hours prior to use...it is not mentioned on any of literature from Yamaha, but is it a good idea to do so even though all of the equipment is digital?

 

[darien87]

Load of crap.

 

[Wheelinarcher]

Load of crap.

lol...just plug and play?

 

[3db]

+1 on the load of crap . No break in required. Plug and play as long as the unit is up to room temperature and has been for several hours.

 

[slipperybidness]

+1 on the load of crap . No break in required. Plug and play as long as the unit is up to room temperature and has been for several hours.

I think what he is getting at is....don't bring in equipment from the COLD and immediately plug it in and turn it on. Just be sure it's at room temp first.

Yeah, in general, I think break-in on electronics is BS.

I do think there is a bit of break-in on speakers.....but honestly the data that I have seen absolutely suggests otherwise.

Now, tube gear and breaking it in might be a different animal.

 

[3db]

I think what he is getting at is....don't bring in equipment from the COLD and immediately plug it in and turn it on. Just be sure it's at room temp first.

Yup

Yeah, in general, I think break-in on electronics is BS.

I do think there is a bit of break-in on speakers.....but honestly the data that I have seen absolutely suggests otherwise.

Now, tube gear and breaking it in might be a different animal.

The plate heaters need to warm up the plates to allow for sufficient release of electrons but that is warm up, not break in

 

[Wheelinarcher]

Thanks everyone, that is what I was thinking, warm up, not break in.

 

[Swerd]

This reminds me about the never-ending debate I used to hear in the days before solid state, about amplifier warm up. How long should vacuum tubes warm up? Among some, it seems, warming up your amp for longer time periods allowed you to claim being a truer audiophile.

Years ago when I first started working in biochemistry labs, a standard lab tool was a UV/visible light spectrophotometer. These instruments have a strong and stable light source, a tungsten bulb for visible light, and deuterium bulb (similar to a vacuum tube) for UV light. There was also a similar debate about how long you should warm up the deuterium bulb before using it. Most people didn't worry too much and allowed about 10 minutes warm up. We got a new smart-ass guy in the lab who swore we were all wrong — he wouldn't work on it unless it warmed up at least 30 minutes – an hour was better.

Eventually, we got a new spectrophotometer. It had a built-in electronic temperature sensor on the deuterium bulb, and recorded the temperatures on a spreadsheet. It soon became clear that the bulb's temperature leveled out between 1 and 2 minutes after switching it on. Even 10 minutes was overkill .

 

[markw]

I think what he is getting at is....don't bring in equipment from the COLD and immediately plug it in and turn it on. Just be sure it's at room temp first.

This is to prevent condensation from producing water inside the unit. Some early VCR's had a circuit built in that would prevent them from operating until it had reached a certain physical temperature, or something like that.

 

[slipperybidness]

Yup


The plate heaters need to warm up the plates to allow for sufficient release of electrons but that is warm up, not break in

Well, have you heard the phrase "your tubes are either breaking in or breaking down".

I do have a tube amp and a tube pre. But, I won't claim to be a tube expert.

Concerning speaker breaking in: I can tell you with certainty that polymers "ie surrounds, etc" absolutely go through a break-in period where the molecules stretch and plasticizers/solvents outgas (think new car smell). I am a chemist by trade and this is a well understood phenomena. But, the measurements as presented on AH by Gene, clearly show that this break-in is not audible. IIRC, I think the case was that often the sample to sample variation was greater than the pre vs post break-in measurements!

 

[slipperybidness]

This reminds me about the never-ending debate I used to hear in the days before solid state, about amplifier warm up. How long should vacuum tubes warm up? Among some, it seems, warming up your amp for longer time periods allowed you to claim being a truer audiophile.

Years ago when I first started working in biochemistry labs, a standard lab tool was a UV/visible light spectrophotometer. These instruments have a strong a stable light source, a tungsten bulb for visible light, and deuterium bulb (similar to a vacuum tube) for UV light. There was also a similar debate about how long you should warm up the deuterium bulb before using it. Most people didn't worry too much and allowed about 10 minutes warm up. We got a new smart-ass guy in the lab who swore we were all wrong — he wouldn't work on it unless it warmed up at least 30 minutes – an hour was better.

Eventually, we got a new spectrophotometer. It had a built-in electronic temperature sensor on the deuterium bulb, and recorded the temperatures on a spreadsheet. It soon became clear that the bulb's temperature leveled out between 1 and 2 minutes after switching it on. Even 10 minutes was overkill .

LOL!

I was always told to let my deuterium lamp warm up for 30 minutes prior to analysis! "Swerd the Mythbuster".

How about if you wanted to measure and/or troubleshoot your tube amp? How long should it warm up before attempting that?

It's a legit question, I have a channel out on my Dynaco ST-70 and I haven't felt like troubleshooting it yet.

 

[Swerd]

LOL!

I was always told to let my deuterium lamp warm up for 30 minutes prior to analysis! "Swerd the Mythbuster".

How about if you wanted to measure and/or troubleshoot your tube amp? How long should it warm up before attempting that?

It's a legit question, I have a channel out on my Dynaco ST-70 and I haven't felt like troubleshooting it yet.

Do it the scientific way. Measure the ST-70 in the first minute after switching it on, and again after 10 minutes. Compare the results. This will be far easier to do than endlessly debate such a silly topic .

If you want to be compulsive, do the measurements a third time after an hour of warm up.

 

[highfigh]

LOL!

I was always told to let my deuterium lamp warm up for 30 minutes prior to analysis! "Swerd the Mythbuster".

How about if you wanted to measure and/or troubleshoot your tube amp? How long should it warm up before attempting that?

It's a legit question, I have a channel out on my Dynaco ST-70 and I haven't felt like troubleshooting it yet.

Did that channel go out suddenly, or did it take its time?

 

[highfigh]

Someone told me that his new amplifier power cords reduced the warm-up time from 4 hours to about 20 minutes.

He also has ceramic speaker cable stands, so.....

 

[slipperybidness]

Did that channel go out suddenly, or did it take its time?

It just quit all of a sudden. Using it one day, didn't use it for a few days, then when I came back....dead right channel. At the time, I was using it off my mixer for drum machine and driving Infinity P363s.

Also, I had installed an upgrade on the outputs to allow for 4 or 8 ohm taps, maybe 2 months before the channel died. It worked fine for 2 months after the upgrade though.

Any good ideas?

I have function generator, DMM, and O-scope, and I built this ST-70 from a Bob Latino kit. So, I'm pretty confident that I can find and fix the problem.

I've just been devoting my limited time on building a couple of chip-amps, haven't even tried to look at the ST-70 yet. And, I am much more comfortable and experienced with SS than tubes.

 

[highfigh]

It just quit all of a sudden. Using it one day, didn't use it for a few days, then when I came back....dead right channel. At the time, I was using it off my mixer for drum machine and driving Infinity P363s.

Also, I had installed an upgrade on the outputs to allow for 4 or 8 ohm taps, maybe 2 months before the channel died. It worked fine for 2 months after the upgrade though.

Any good ideas?

I have function generator, DMM, and O-scope, and I built this ST-70 from a Bob Latino kit. So, I'm pretty confident that I can find and fix the problem.

I've just been devoting my limited time on building a couple of chip-amps, haven't even tried to look at the ST-70 yet. And, I am much more comfortable and experienced with SS than tubes.

Original tube sockets? Are they loose, at all?

Do all of the heaters light up? Could be a simple problem with a small tube, like the phase inverter. I would swap that and the other small tubes, then check the voltages.

I got an old Magnatone from someone who had asked about intermittent operation and I told him what he needed to do (wiggle the tubes and if it comes back, clean and re-tension the sockets). For whatever reason, he didn't and months later, asked if I wanted an old lap steel guitar that he decided he didn't need. While we discussed this, he again asked about the amp before writing, "I'll tell you what- I'll include the amp for the same price".

As he had said, it was flaky and I wiggled the tubes to get it to work. I think the newest tube is from 1964 and one of the first things I saw when he handed it to me was the Bugle Boy 12AX7 in V1.

 

[slipperybidness]

Original tube sockets? Are they loose, at all?

Do all of the heaters light up? Could be a simple problem with a small tube, like the phase inverter. I would swap that and the other small tubes, then check the voltages.

I got an old Magnatone from someone who had asked about intermittent operation and I told him what he needed to do (wiggle the tubes and if it comes back, clean and re-tension the sockets). For whatever reason, he didn't and months later, asked if I wanted an old lap steel guitar that he decided he didn't need. While we discussed this, he again asked about the amp before writing, "I'll tell you what- I'll include the amp for the same price".

As he had said, it was flaky and I wiggled the tubes to get it to work. I think the newest tube is from 1964 and one of the first things I saw when he handed it to me was the Bugle Boy 12AX7 in V1.

All of the EL34 tubes are glowing, and it seemed like I was able to set the bias fine. I did give all the tubes a good wiggle and did swap the left/right output tubes. Still no dice. That's about all I have done for troubleshooting. I figure if I open it up, feed it a 1kHz sine wave, and start snooping around with my DMM and O-scope, then I should be able to root out the problem.

To be clear, this is a NEW ST-70 clone that I built from a kit (Bob Latino / Tubes for Hi-fi vendor). Bob is well known to be the best in the business when it comes to customer service and troubleshooting help. But, I haven't contacted him yet.

I'm not exactly hurting for amps! Pio AVR, Parasound 1206, Boxed Kit Amp Gobo, and working up a couple builds on LM3886 and LM4780 now too.

Feel free to critique my current work. Constructive criticism is always welcome, don't worry too much about hurting my feelings (assuming that it's fact based and objective comments).

http://forums.audioholics.com/forums/threads/new-chipamp-project-thread.92513/

 

[highfigh]

All of the EL34 tubes are glowing, and it seemed like I was able to set the bias fine. I did give all the tubes a good wiggle and did swap the left/right output tubes. Still no dice. That's about all I have done for troubleshooting. I figure if I open it up, feed it a 1kHz sine wave, and start snooping around with my DMM and O-scope, then I should be able to root out the problem.

To be clear, this is a NEW ST-70 clone that I built from a kit (Bob Latino / Tubes for Hi-fi vendor). Bob is well known to be the best in the business when it comes to customer service and troubleshooting help. But, I haven't contacted him yet.

I'm not exactly hurting for amps! Pio AVR, Parasound 1206, Boxed Kit Amp Gobo, and working up a couple builds on LM3886 and LM4780 now too.

Feel free to critique my current work. Constructive criticism is always welcome, don't worry too much about hurting my feelings (assuming that it's fact based and objective comments).

http://forums.audioholics.com/forums/threads/new-chipamp-project-thread.92513/

Does yours have 12AU7 or 6SN7 tubes for the driver/PI? First, I would swap the L and R drivers and if that doesn't matter, move the PI to one of the other locations. If that messes up one channel, you know where the problem is.

Does this have bias indicators, or do you just use a meter? Either way, is the bias current stable?

Any noise from the bad channel, at all? Have you tried using one of the other taps?

 

[scwlw]

maybe crap but my Anthem 225I was shrill for weeks and soundstage suffered also, your ears will tell you but if your not happy with the sound by the return date RETURN it. Mine smoothed out and I kept it.

 

[SurvivalDad]

You should always let it sit at "room temp" for a while.

-------------------------
SurvivalDad
Father Time!