This past weekend we were playing on a dock at a yacht club…temps in the low 80’s…sunny… beautiful day until my power went out on the L1 in the middle of a Toby Keith song.
At this point it became apparent that the sun was baking the unit which was in direct sunlight for the past 2 hours. Turning off the power and then switching it back on brought her back to life.
We took a half hour break to let everything chill out as I made a phone call to my buddy Andrew Douglas to get his take on things. He agreed about the overheating and advised me to put some towels over the power base but to be careful not to cover the vent by the handle.
The rest of the day went on without a hitch.
Is there some kinda breaker inside these things that automatically resets when you re-power up?
JD…
Glad to hear that the problem didn’t repeat.
I just finished going through the documentation and there doesn’t seem to be any indication of an auto-reset breaker, but it must be the case. My Classics are fuse-protected and this is noted in the Classic manual. There’s no mention in the Model II manual of a manual-reset breaker or a fuse.
I cannot imagine that there isn’t a protection device of some sort in the power stand, so it must be an auto-reset breaker.
I play outdoors a fair bit and always try to keep the electronics shaded and take care to keep the vents clear. The B1 covers make pretty good makeshift sunscreens. I got into that habit because the bass rig that I used before I went all-Bose had a 1200-watt power amp in it that had a reputation for thermal shutdown. I took care to make sure it was well-ventilated and shaded, and never had any problem because of that.
Same deal with my Classics…I’ve played outdoors in near-100-degree heat and not had any problem because I’ve taken steps to keep the electronics relatively cool.
I think if you keep your stuff shaded from here on out it’ll be fine.
JD1 and I have noticed NetTek’s post in his gig report thread indicating that his T1 also shut down.
I’m confident that JD1 experienced thermal shutdown of the power stand based on his description of the circumstances (simplest explanation). But it’s possible that it was just his T1 that tripped, because he didn’t notice the state of the lights on the power stand in the sun.
Can one of the at-Bose crew chime in and describe the functioning of the protection circuitry in the Model II power stand and the T1?
What can cause the units to trip off? Over voltage? Under voltage? Heat? What’s the behavior of the protection circuitry after that…do you have to manually cycle the power, or will it auto-reset?
I just got off the phone with the service department after a 30 minute wait. The guy I spoke with deferred to one of the other more knowledgable guys since the T1 is so new and doesn’t have a wide history of troubleshooting available.
He got back on the phone and said that they don’t have any idea what caused it. We’ll make a log of this call and give us a call back if it ever happens again".
Well, that just about does it, don’t it?
Haven’t experienced heat issues with the L1-II power stand above and beyond any other amp that I have used, but I will say that the T1 worries me somewhat.
When I received my replacement unit last week, I hooked it up to the L1-II system out in my enclosed garage (where the air temp was in the mid-90’s), checked it out, then walked away for about an hour leaving everything on. I was really surprised at how hot the T1 was upon my return. Since I had not yet packed up my original, defective T1, I swapped units out, just to A-B the heat issue. Same on the T1 that originally had problems with…so, I said to myself - “maybe it’s just the heat in this garage”. By the same token, this IS Florida, and I do play outdoors a lot…and in the summer, if it’s an afternoon and it isn’t in the 90’s, then it must be raining. We’ll just have to see.
(Just hope we don’t have a Mackie SRM450 situation on our hands.)
DB
Let’s watch the situation and see what happens. Now that there are a bunch of T1s out in the wild, if there’s some design problem that’s going to cause them to arbitrarily shut down it should make itself evident pretty quickly.
I still think your shutdown happened because you parked your system out in the sun in the middle of summer with no shade. When in doubt, default to the simple answer.
With any new product, it takes time for the troubleshooting knowledge base to be built. Car manufacturers, for example, literally spend years and millions of dollars field-testing new designs to work the kinks out, but problems that didn’t get discovered during testing happen anyway.
That’s why first-year cars have more recalls than those from later on in the production run. Ever wonder what the customer service calls for brand-new cars that later get recalled must sound like?
There can be issues with brand-new, version 1.0 equipment, no matter what kind of equipment it is. That does NOT in any way mean that there WILL be issues with version 1.0 equipment.
Does the T1 have some sort of issue that causes it to shut off at random? Highly unlikely.
Does the system protect itself when overheated? Sure.
Is it probable that putting the system out in the sun in late July and then using it for several hours at high volume caused it to overheat? I suspect so.
quote:Is it probable that putting the system out in the sun in late July and then using it for several hours at high volume caused it to overheat?
Is it me or does it seem kinda odd that both this post and NetTek's similar post was up all day with zero comments from Anyone-at-Bose???
This issue seems to have occured with several users. I doubt it’s a design flaw as I would have come up in long testing process. Hopefully there was a power interruption that caused this and not a manufacturing problem.
I know there was a manufacturing issue with broken fasteners rattling around in a shipment of T1s so I hope Bose is looking into this.
Andrew – With all due respect, I think that doth protect-eth the T1 too much… 
You are right on this point – Stuff happens. I’m not going to worry too much about it right now. I used the T1 for another gig on Sunday and it was fine. I’ll be using the system about every weekend for the next month or so, and with that any other problems should surface during that time.
If it’s a software issue, the USB connection should make for an easy firmware update. If it’s a hardware issue, the Bose guys aren’t shy about overnighting new gear as needed. Either way, worse case scenario is that I have to revert to plugging direct into the PS1 again for a gig or two. Not an issue in the short term.
Re: Heat – Frankly, I don’t buy it. I believe the PS1 is built more rugged than you’re giving it credit. Low 80’s with a wide open vent and fan drawing air into the unit should keep everything within operating parameters. My guess is that JD’s T1 had the same hiccup as mine.
Re: Troubleshooting intermittents – Yeah, you can pull your hair out determining root cause. Hardware or software? Main firmware or the I2C used to communicate between components? The best thing that can happen is a couple company friendly users report back issues and let the guys at the lab re-create and repair. That’s the situation we have here. I’m not the slightest bit angry about what happened. I’m just reporting back what happened in the field…
Either way, I do believe it’s an isolated incident and has in no way impacted my trust in the L1 system…
Hey all,
Sorry for not replying sooner!
JD1, please look for a private post from me.
Heat - The L1 power stand is designed to shut down from excess heat. In a performance this is possible if it’s in direct sunlight and being played loudly. It would recover on it’s own once it cooled down (but that could take several minutes). It could also restart if the power switch was turned off then on.
But to NetTek’s point - I can’t say for sure if that is what happened to JD1. But Andrew’s advice to try to keep the electronics out of direct hot sunlight is good.
Don - The T1 will get warm to the touch in use, more so if it’s in a hot environment. This should be no problem, it does not indicate a defective set.
Please rest assured we are looking into every one of the issues reported here. We can not do it without your feedback, so many sincere thanks for the comments, and keep on letting us know what you find.
Hey NetTek - thanks for your understanding of the difficulty in finding and fixing a reported intermittent problem. With your help we’ll find them!
Bill
Weeks ago I posted about my T1 suddenly freezing up with no audio coming out of my L1 Model 1. This happened in an air conditioned bar. I was unable to repeat the problem in over 12 gigs and testing at home. After seeing some of these posts, I’m a little concerned.
quote:Originally posted by JD1:
my power went out on the L1 in the middle of a Toby Keith song.
Were the rest of you guys playing Toby Keith? That could explain a lot. Just Kidding.
I have been using both the classic and MII in pretty hot weather here in So Ca. Over a 110 sometimes, and outdoors. No problems yet. Once no shade, still ok. 2 B1s attached at all times, so it's being driven. I know this is no help, just sharing.
quote:Originally posted by NetTek:
Andrew -- With all due respect, I think that doth protect-eth the T1 too much...
Nah, simply applying Occam's Razor. The simplest answer that fits the facts is the one most likely to be correct.
I used to be the default IT guy at a small publisher where I was an editor. I can't tell you how many times I fixed "dead" equipment by looking in back of the machine and plugging it into the wall.
quote:Re: Heat -- Frankly, I don't buy it. I believe the PS1 is built more rugged than you're giving it credit. Low 80's with a wide open vent and fan drawing air into the unit should keep everything within operating parameters.
If the air temp is in the 80s the temp on a black surface out in the sun will be much higher than that. Next time you've got a warm day go out and put your hand on some fresh asphalt.
If the unit is in the shade, then it actually is seeing temps in the 80s.
Changing the color of the surface from black to white will do A LOT in a situation like this. I think Andrew’s advice, given that most towels are light colored, was right on the money.
The only thing to be a little careful about in addition to the obvious issue of not blocking the vent in the handle, is to not block the vents that are on the bottom of the unit. Draping a big towel over the unit could impede air flow through these lower vents.
I think that if you taped a sturdy piece of white construction paper (or something similar) over the front of the PS you might get the maximum benefit of reflecting instead of absorbing the sun’s heat.
Ken
Among the many bizarre things I’ve done in my life I was involved in the construction of a fiberglass airplane. Heat is a major concern here, because the epoxy resin used has to be kept below a certain temperature or it may lose strength.
Here’s a chart that these builders use that maps surface temperature of various colors against air temperature in full sunlight. What’s missing, of course, is the altitude of the sun…but you get the idea.
Now that’s an interesting graph… never figured white was even better than aluminum. Either way, maybe a bit of aluminum foil wrap molded around the base may be an easy cure…
By the way, Bill-at-Bose and I are going back and forth with a private posting in a troubleshooting scenario so I’ll post results as they occur. Bill has been very helpful with this whole thing.
I think that the important thing isn’t color necessarily, it’s shade. You’ll recall that during the first gig I saw you play I used the B1 covers to shade the system that was in the sun.
Looks do count for something…
(if that’s true then why am I getting up on stage in front of the public??? 
)
I’ve spent some time with JD1, who very graciously was willing to answer lots of specific questions about exactly what happened - which lights were on, what the exact sequence of events was, etc.
Thanks, JD1!
Ands I’ve deduced what the cause of the shutdown was:
Andrew was correct (I should say as usual . . . ), and it was not the Toby Keith song. The L1 was behaving as it should, and shutting down under the excess heat.
We know it was not a power surge or dip, since there were two units plugged in, and that would have affected both of them. We also know that the T1 had no power to it (since the lights on it went out completely). That happened because when the L1 protects itself it can shut down power to the T1 as well.
So, after all that, I am as certain as I can be that the problem was over heating of the L1, and was probably “normal” under the circumstances.
I find it really interesting to look at Andrew’s chart: At 80 degrees out, in sunlight, a surface can go from 120 degrees for a white surface to almost 200 degrees for a black one. That is absolutely stunning to me.
I saw a movie made by Bell Laboratories in grade school - they had a white car and a black car in the sunlight and cracked a raw egg onto the hood of each car. On the white car’s hood the egg just sort of oozed down until it slid off the front of the hood.
The black car fried that sucker right up! Poppin and boilin as soon as it hit the black metal!
White towels for direct sunlight - 
Bill
My apologies to Andrew for doubting him. I should have let common sense prevail.
Bill – Now that we have JD’s issue solved, drop me a line so we can figure out why my T1 locked up!
quote:find it really interesting to look at Andrew's chart: At 80 degrees out, in sunlight, a surface can go from 120 degrees for a white surface to almost 200 degrees for a black one. That is absolutely stunning to me.
Y'know....after looking a bit closer at that chart....at 30 degrees ambient air the peak surface temp is 85??? Hmmmmm.....not here in Connecticut it ain't!!!