Please help...my brand new amp is dead... :-( (1 Viewer)

[Dave Falasco]

Hey, all. Yesterday I picked up a B&K Reference 30 and a 7270 power amp. I was up until 1 in the morning hooking everything up, but I finally got it up and running and ran through a few DVD-Audio discs to hear what it sounded like. I definitely liked what I heard, but it was late and I couldn't crank it up very loud.
Today I came home from work all anxious to really put the new gear through its paces, and I was greeted with kind of a plastic-y smell when I came in the door. Uh oh... I went downstairs and my brand-new amp will not turn on now. The power light will not come on, and plugging the amp in different outlets doesn't help. It's stone dead. :frowning:
After I finished my brief listening session last night, I felt the amp and was surprised to feel how hot it was, but I had read that B&K amps do run hot. The amp is in a cabinet, but it's open in the back, I left the doors open in the front, and there's 3 inches of clearance on top (exactly what the manual recommends). I should mention, I did leave the amp on overnight and while I was working today because I had read that turning it on and off shortens the lifespan.
Does it sound like I've somehow managed to fry my brand-new amp in less than 24 hours, simply by leaving it on in a cabinet with the recommended ventilation room available??? I have tried replacing the AC line fuse, but that didn't bring it back to life. Could there be some other problem? Does this sound like a defective unit, perhaps? Any ideas what the next step would be? I tried calling B&K but no one is picking up on the 800 line.
Ugh, how disappointing...

 

[Rob Rodier]

Sounds like a defective unit to me. The smell indicates something bad happened. It is impossible to give you a specific answer, I would give the dealer a call.
Good Luck, nice gear when it is working too
-rob

 

[Michael Mathius]

Dave:
I would not worry too much if I was you. I'd just return it to the dealer and nicely request a replacement.

If that does not work then hopefully you bought it with a credit card. But I surely would not buy from a dealer again if he/she does not replace a two day old unit. Hopefully you wont have to go through this additional hassal.

Good Luck.

Michael

 

[Yogi]

Awww thats such a bummer. I was looking forward to your experience with your new gear as its a dream HT system for me to have a ref 30 hooked to a ref 7270:frowning: You can always exchange it at any tweeters. If I were you I'd do exactly that.
As far as the amp itself. MOSFET amps tend to run hotter than BJT ones. And I would give it more than 4" clearance all the way around. If possible I would also put a 3" CPU fan on top of it to suck out the hot air. You can get one at partsexpress and they are fairly quiet. Also I wuld never leave an amp on all the time. I just turn on my amp 15 mins before I start listening and shut it down at night. Capacitors are the only components that age in an AMP and their life shortens exponentially with temp. SO I think its a good idea to turn of amps at night. B&K amps have a fairly high bias, if I am right, so they dissipate more heat when idling than when they are playing. Plus having 7, 200 W channels of MOSFET amplification in a single box is a recipe for furnace. Exchange this one and keep the next one cool and you should be fine.
My 2 cents.

 

[Lee Scoggins]

I would not worry too much if I was you. I'd just return it to the dealer and nicely request a replacement.

This is good advice. They should accept a return. I doubt it was your fault based on your comments. Call the dealer immediately and don't throw any boxes or receipts away in case they get nasty.

 

[Dave Falasco]

Thanks, guys. I did just that--I called Tweeter and explained what happened, and they have a new unit winging its way from Boston as we speak. I'm to pick it up on Monday. They were very nice about the whole thing...I was disappointed with the meltdown, naturally, but thumbs-up to Tweeter for their response.
Yogi, thanks for your suggestions on keeping the brute cool. In my rack it will be difficult to get another inch of clearance on the top, but I will look into a separate cooling fan, and from now on I will certainly turn the thing off when I'm not using it. Even if I did have a defective unit and a normal amp wouldn't have burned out like that, I don't think my central air could compete against an amp that throws that kind of heat anyway...
I see that you are just up the road in Middletown...when I get the replacement unit and I have everything wired up, you are quite welcome to come down and give the B&K a listen if you like. PM me if you're interested and I'll send you directions.

 

[Todd Hochard]

I'd also recommend turning it off when not in use. You found out that leaving it on certainly can shorten its lifespan.
However, make sure that you don't have the + and - to any channel shorted together, either at the amp or the speaker. Take care to watch out for those stray bare strands- they can be your undoing.
Also, is there a way you can place the amp on the top of the cabinet, out in the open? This would be particularly easy, if you have a very tall entertainment center. The better it breathes, the longer it will last. My Denon AVR-3300 receiver (5x105) recommends 4" on top and back, so I find it hard to imagine that a 7x200 high bias amp can make do with less.
Todd

 

[Yogi]

I see that you are just up the road in Middletown...when I get the replacement unit and I have everything wired up, you are quite welcome to come down and give the B&K a listen if you like. PM me if you're interested and I'll send you directions.

Thanks for a offer David. I might take you up on it one of these days. Let me know when your system is set up and all tweaked up. I am still struggling to setup my system optimally. I have too many variables in my system that are not at par with each other. My amp is 4 times the cost of my receiver. My speakers are not all matched up etc etc. Just too much discord right now, but someday...when I have more money....

 

[NickSP]

Hi Dave, I have not used B&K equipment but I know they are good quality components. I definitely think you got a bad unit as leaving an amp on overnight will definitely not kill the amp altogether. Also does the amp turn on/off by remote or some kind of a 12V trigger that connects to the pre/pro? Would that not turn the amp on and off every time you turn on/off the pre/pro?

 

[Kirk Mango]

Dave,

I have talked extensively with B&K directly about how to run their system and there recomendation is to use the 12v trigger from the Ref30 to the amp and when you put the preamp to sleep it will put the amp in sleep mode. Just enough juice to keep caps filled. No heat builde up. They strongly recomend this. That amp will draw over 20 amps at initial startup if you turn it off and on all the time. I own a Ref 30 / Ref7250 / Ref2220 and the 7250 will pop the 20 amp circuit breaker if turned off all the time. B&K definately recomends 12v trigger and sleep mode for its amps. Call them and ask yourself. Ask for Gerry. Very Helpful and extrmemely knowldegable.

Kirk

 

[Dave Falasco]

Nick, there may be a remote trigger on the amp (I can't check because I'm at work right now), but getting up and turning it off manually isn't a big deal. I have to turn my Fidek amp for my SVS subs off manually anyway, so I already have to get up and walk to the equipment rack. I left the amp on only because I thought it was healthier for it. Uh, guess not, huh? :b
As for putting the amp on top of the rack, I have no problem with that, but something tells me my endlessly understanding wife may finally balk at that. She loves our theater almost as much as I do, but she really likes how it LOOKS as much as how it SOUNDS. So we've got a Pioneer Elite RPTV with that shiny black finish, a cabinet rack from Pioneer with the same shiny black finish, and Mirage speakers all around with that same finish. A squat, square, matte-black box on top of the cabinet rack would probably not fly with her smooth-black-shiny-feng-shui thing she's got going on in there.
Could be worth a shot, though...there certainly wouldn't be a ventilation problem then!

 

[Rob Rodier]

I'd also recommend turning it off when not in use. You found out that leaving it on certainly can shorten its lifespan.

For clarification;

I just wanted to say that I leave my amps on all of the time. I have never had any problems. Many will recommend doing so, including some dealers and manf.

The fact that the B&K was left on, had nothing to do with the failure. It was some type of defect.

I'm not trying to tell anybody to turn their amps on. At the same time, saying that leaving them on shortens lifespan is not neccessarily true.

-rob

 

[Kirk Mango]

I agree. Have talked to many, including B&K directly, it is best to leave an amp on. The surge you get from turning it on and off all the time is much harder on the amp, and switch for that matter, then leaving it on. That is why B&K built there equipment with a 12v triger. Use this trigger, it is designed that way to save wear and tear on the amp.

Kirk

 

[Yogi]

The surge you get from turning it on and off all the time is much harder on the amp, and switch for that matter, then leaving it on.

I fully agree with this one esp. the one about the switch. I have heard of instances where the switch plate welded itself due to meltdown from the sudden high current surge. Any amp (which is just about every amp these days) that has a trigger switch should be used in that manner. This would enable turning the amp on and off just from a signal from the preamp and not tax unduly on power supply caps in the long run. If the ventilation is adequate such that the amp doesnt exceed room temperature in standby then there is no reason to turn it off, ever!!! It would easily last you a lifetime. Tube amps however are a different ball game.

My 2 cents.

 

[Dave Falasco]

Sorry, Kirk, somehow I missed your initial post (you must have posted while I was typing a reply), but that's very good information (direct from the horse's mouth, as it were) and I appreciate you sharing it with me. I've never used a 12v trigger before, but it sure sounds like that's the way to go with the B&K gear. I did think it a bit odd that the preamp has a sleep mode but the amp doesn't. Now that you've explained that the preamp kind of puts the amp to sleep when hooked up with the trigger, that sounds like exactly what I need to do.
...just as soon as I figure out how...

 

[Yogi]

just as soon as I figure out how...

Its just an adapter like connector that goes from the preamp to the amp. And you probably have to flick a switch that puts the amp in remote control mode. Its that simple.

 

[Paul Clarke]

Dave,
Here's a link:
http://www.hometheaterforum.com/htfo...ht=12v+trigger
Or you can always just use a leftover 12V adapter if one is handy and split & strip the +/- leads.