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I just blown up two amps in one week-end


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#1 of 83 OFFLINE   PhillJones

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Posted August 16 2004 - 01:05 AM

I know this is a long post but I urge you to perservere. There's nothing like a bit of shadenfreuder to cheer you up on a Monday morning.

Finally my shiny new Amex with the 6 months interest free comes through so I head down to a dealer in Boston to buy my long awaited RSX-1056.

Giddy as a school boy I bring it home, connect a source a my speakers, turn it on and BANG!!!! Fortunately, the dealer is open on Sundays so I give them a ring and they offer to do a straight swap, so far everybody thinks that it's just a bad bit of electronics.

So, cut to Sunday afternoon, I plug the amp in with no source and no speakers and it powers up with no sound and light show so I unplug it, wire up the speakers and a source and turn it back on. Guess what?

So, I go out and get an electronic tester find that there is a short in my new speakers. Well darn it says I, only in not so many words.

The position now is that there probably is a 'persona non gratis' bill up in the only Rotel dealer in Boston with the face of Phill 'amp killer' Jones on it (This is not literally true). They refund my money but wouldn't offer to replace it or sell me anything else. I got the distinct impression that I wasn't welcome.

So now I'm stuck with my home theater dreams in tatters. I'm left with three questions.

1) Are there no fuses or protection circuits in these things. The short was there from power on so shouldn't a fuse blow before the electronics go up in a sheet of flame?

2) Are Rotel amps just not so robust? Should I look for a better protected amp? My wife now thinks I shouldn't get onw on the grounds that, 'they blow up when you look at them funny.'

3) If I do replace it, where the hell am I gonna get it from? Obviously, this last question is a bit difficult to answer since the only rotel dealer in Boston is not at home to Mr amp killer.

Your's Frustrated

The phantom electronics fryer



Edited to correct model number. I'de managed to upgrade my amp without spending any money. Posted Image

I've edited slightly to avoid any inexactness in describing my dealings with the dealer. I don't want to be accused of bad mouthing anybody.

#2 of 83 OFFLINE   Dan J S

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Posted August 16 2004 - 01:30 AM

You've just convinced me to never buy a Rotel amp. Any amplifier should have protection against this kind of stuff. Even my ancient Yamaha reciever will shut down if I short circuit the speaker cables. I found out about that first-hand, on two occasions.

#3 of 83 OFFLINE   Wayne Ernst

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Posted August 16 2004 - 02:01 AM

I find it odd that such a protection was not included in the amp. After all, it can't be that costly to create a circuit to handle such protection and fuses cost nearly nothing.
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#4 of 83 OFFLINE   James W. Johnson

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Posted August 16 2004 - 02:04 AM

The dealer got mad? I hope you cross them off your list of places to buy from.

#5 of 83 OFFLINE   Darrel McBane

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Posted August 16 2004 - 02:05 AM

Dan,You can't blame Rotel for a short in Phills speakers. I've owned Rotel amps (1090 and 1095) for years and they have performed perfect for me. I use a surge protector (Monster 5000 line conditioner for the 1095 and VansEvers Reference line cleaner for the 1090). Sorry to hear of you loss Phill. In the past I've seen people put fuses on speakers to protect power damage to the speaker. Most if not all modern speakers don't require people to do this. What speakers do you own Phill?
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#6 of 83 OFFLINE   PhillJones

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Posted August 16 2004 - 02:29 AM

Tannoy Mercury mX3-M I spoke to Rotel, they say that receivers have much less protection than seperate amps. My old Rotel stereo integrated had plenty of protection, why doesn't this model? Am I expecting too much? I know we can't blame Rotel for a short in the speakers but should the amp really destroy itself under such circumstances? If this is true for all receivers then I can either choose to live with it and just hope for the best or find a lower end pre-power combination to keep in my budget. I'm gutted because I really like the sound of the rotel but now I'm sacred to connect another in case something else ever goes wrong. To make matters worse, authorised Rotel dealers won't do mail order so I'll have to get somebody to give me a lift to Framingham if I want a replacement. Home theater sucks! (not really)

#7 of 83 OFFLINE   Dan J S

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Posted August 16 2004 - 02:44 AM

But a short in the speakers (before the voice coil), is the same as a short in the speaker cables, is it not? Every amplifier should have protection against this because of how easy it is to accidently touch connectors together.

#8 of 83 OFFLINE   JustinCleveland

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Posted August 16 2004 - 02:49 AM

How the hell can any amp produced in the last 10 years not include short protection? I've even had HTiBox's that would shut down if there were a short. Sorry to hear about your problems, though, Phill!

#9 of 83 OFFLINE   PhillJones

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Posted August 16 2004 - 02:56 AM

The short is right at the terminals. It's electrically the same as a short in the cables. So the verdict is that Rotel RSX-1065 has a flawed design?

#10 of 83 OFFLINE   Brad_Harper

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Posted August 16 2004 - 03:16 AM

Short circuit protection in the output stage of an amplifier is a must!!! You should be able to short the + and - terminals together and have the amp survive. It is just common sense designing. Rotel has obviously taken the cheap route and left out the $1 worth of parts necessary for adequate short circuit protection. I would expect better from a company with Rotels reputation. Based on this info I would never buy one now!

#11 of 83 OFFLINE   Wayne A. Pflughaupt

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Posted August 16 2004 - 03:19 AM

Well, I’m certainly inclined to agree with that assessment. As Dan noted, any short in the speaker is the same as getting the speaker wires crossed. This should not make a well-designed amp instantly blow. Consider this: If it fried with a dead short, what will it do with a difficult load? For instance, it sounds to me like if you hooked up a trio of 4-ohm speakers to this thing, it would play merrily along until the minute it went up in smoke. After all, if it didn’t have protection against a zero-ohm load, why would it have any against a 1-ohm load? I’d take a pass on this one. Look for an amp with visible, replaceable fuses on the back panel, or one that has a delayed click from a relay when you turn it on. Regards, Wayne A. Pflughaupt

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#12 of 83 OFFLINE   PhillJones

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Posted August 16 2004 - 03:31 AM

I'd like to read a defence from Rotel on this. They claim that receivers can't have as much protection as outboard amps. but what Wayne says is very damning. Is there a way of including them in this discussion? The second question is, what alternative should I go for? I really like the sound of the Rotel, I much prefered it to the NAD which seemed harsh and distorted in the high frequency. The rotel had plenty of oomph whithout loosing detail, just like all my other Rotels have sounded. Sound like an amp you know?

#13 of 83 OFFLINE   Yogi

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Posted August 16 2004 - 03:45 AM

Its a fault in Rotels design, IMHO. Even my 10 yr old Sony DE prologic receiver had protection circuits to deal with shorts. This is totally un-acceptable. Why are you stuck on Rotel? Are you looking at other receivers besides Rotel?
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#14 of 83 OFFLINE   Wayne A. Pflughaupt

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Posted August 16 2004 - 04:07 AM

Baloney. I’ve seen HT receivers that would shut down in 15 seconds when they had a pair of 4-ohm speakers connected. Regards, Wayne A. Pflughaupt

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#15 of 83 OFFLINE   Andrew Pratt

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Posted August 16 2004 - 04:17 AM

That's really odd that it blew up the receiver. I've tripped the protection on my Rotel power amps a couple of times by accident and it was never an issue. If you like fire me an email about this incident and I'll pass it up the line and see what they have to say.

#16 of 83 OFFLINE   PhillJones

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Posted August 16 2004 - 04:33 AM

Andrew, YGM. Thanks, I appreciate your help.

#17 of 83 OFFLINE   Andy_Steb

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Posted August 16 2004 - 08:01 AM

I hope Andrew can help you out. I would post this on Club Rotel also. I see a real problem with your dealer. To blackball you sounds extreme. A good dealer would get on the phone to Rotel to find out about protection problems. They could of offered to get the unit repaired under warranty. Could of been a $2 internal fuse. If your dealer took the extra step, you post would read different. Somthing like - I had some real problems with Rotel's but my dealer took care of me.

#18 of 83 OFFLINE   Charlie C

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Posted August 16 2004 - 08:45 AM

"wire up the speakers and a source and turn it back up" just wondering, did you have some sort of volume control in this little chain?

#19 of 83 OFFLINE   PhillJones

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Posted August 16 2004 - 08:52 AM

To be fair, he didn't actually say 'Get out, you're banned!'. He replaced the first one but wouldn't replace the second. He just said 'It's obviously a short with your system, it's extreemly unlikely to be two faulty amplifiers, just bring it in and we'll refund your card.' He made me feel very unwelcome and wouldn't give me any serious advise on the matter. Right from the start, I got the feeling that I wasn't rich enough top be in his shop. My wife thought he was a snob. After speaking to him and he saying it was a short, I tracked the short down then called my dad who said it'd be a fuse. I called the dealer back, after thinking about it, and asked if it might just be a fuse and could I just buy a replacement fuse. He did offer to send me a replacement fuse for free but when I took the lid off to identify the fuse I could smell the damage and it wasn't a fuse. I asked him if it should have some protection against shorts and he said that high-end stuff doesn't have as much, as it interferes with the sound quality. I have no idea if this was just bull or not. I don't know what'd happen if I'd try to buy anything else there. I'm not going to try.

#20 of 83 OFFLINE   Charlie C

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Posted August 16 2004 - 09:04 AM

just wondering, did you have some sort of volume control in this little chain? BTW whats the AMEX? I say go to a local pawn shop and buy a POS amp just to do testing, if it blows, you are out, what $30-40? then you are sure its your system and not the rotels. I touch my speaker wires together on accident sometimes and nothing happens, just the sound from the speaker stops. youd have to have the amp working at close to full blast, ie full volume or no volume control, to actually blow the amp. damn its only got 75 watts per. can you describe your whole setup, maybe someone here can identify the problem.




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