Extreme Temperatures= Fuzzy noise?

Tucker_Z

Hello, I have a Marantz SR7400 that is paired with a beautiful pair of RTA15TLs with new tweeters(cooked and burned the last pair of tweeters...). I usually turn it up 85% of the way up for a few hours and it gets extremely hot within one hour. So hot that it actually burns to touch it and can melt no flame candle wax. You can actually hear it tick and ting as it cools down or warms up (like a car does). My room is also much much warmer than the rest of the house but I don't mind it however today while playing tunes for many hours I began to hear a fuzzy noise like white noise. This sound never played before. Puzzled and curious I turn off the receiver for a few minutes to see if maybe a power cycle will help. As I do so I feel the top and its probably about 150°F. I turn it back on and the noise is gone for about 30 seconds of music. Ohp. Yep. I just had it off for 10 minutes and as I was writing this I turned it back on again and I heard it make an extremely faint humming noise (from the receiver itself) then it just shut itself off without displaying any protect message (what it does when it overheats). I'm unsure as to what I should do now. I have a desktop computer case fan that I have rigged to a power supply; should I use this to keep air flowing? Give me your thoughts and opinions c:

CoolJazz

I feel so sorry for the equipment when it gets treated this way!

CJ

Tucker_Z

CoolJazz wrote: »

I feel so sorry for the equipment when it gets treated this way!

CJ

Do explain?

pitdogg2

Thoughts? well Lets see you are over driving the dadgum thing to the EXTREME. The first to go will be tweeters the second to go will be all the outputs on the receiver. Sending a clipped signal WILL DAMAGE speakers. No amount of fans will help you are not curing the symptoms you are masking it weather cool or hot you are still over driving that thing back it down. If you are past 12o clock on the volume knob your going to need new gear soon.

F1nut

My room is also much much warmer than the rest of the house but I don't mind it however today while playing tunes for many hours I began to hear a fuzzy noise like white noise. This sound never played before. Puzzled and curious I turn off the receiver for a few minutes to see if maybe a power cycle will help. As I do so I feel the top and its probably about 150°F. I turn it back on and the noise is gone for about 30 seconds of music. Ohp. Yep. I just had it off for 10 minutes and as I was writing this I turned it back on again and I heard it make an extremely faint humming noise (from the receiver itself) then it just shut itself off without displaying any protect message (what it does when it overheats).

The fuzzy noise you heard was likely one or more transistors letting you know that you just cooked them. The hum and shut down, probably cooked the power supply as well.

I'm unsure as to what I should do now.

Hang your head in shame.

Dennis Gardner

Doctor.....it hurts when I do this.......


Well then don't do that!



I can't just poke fun without offering help. When you blew the tweets, you should have realized that you are driving the amp too hard. You need more power if you want to listen at those levels. The speakers can handle more clean power. It may be too late for your 7400, now that you have fried something in it, but your could have added and amp to that model using the preamp outs.

You will have to do some testing to see if the receiver is still useable as a preamp for external amps.

leftwinger57

I had a term for when running my Klipsch smalls on the loud side "airing them out" to where my avr would go into protection mode and shut down. Thankfully the protecto mode did as advertised and came here and asked the same question your asking, you have to turn it down and it appears it's to late for your receiver and what else you fried. You really did abuse your tunes and now you'll have either the most good looking horribly sounding system in town. Listen to these guys. Avrs/receivers are generally not meant to be pushed to extremes.Hot to the touch is one glaring signal right there. Warm sure after some running never hot.

tonyb

F1nut wrote: »

The fuzzy noise you heard was likely one or more transistors letting you know that you just cooked them. The hum and shut down, probably cooked the power supply as well. .

This ^^^

Plus 85% of the volume dial is your problem....and why you cooked tweets before. Your receiver and possibly the speaks too may be toast. Lessons are a b$tch to learn.

Stick around...read up, ask questions. Learn some things about power, speakers and that darn volume dial that invites sticky fingers.

Tucker_Z

Well guys some of you may be correct to a point. However if you do some reading on this receiver, there are two versions. One with a bad power supply that has a heating issue, and a second with the issue having been fixed. The amp still works just fine. The tweeters I learn now are due to some mischievous big brother attempting to irritate my younger ears with a 20khz signal being pumped full power to my tweeters (GRR). The Marantz still works on all outputs with the same clean output it had been giving at cooler temps. The sudden shutdown was an emergency protection. However I do agree, I need some camps, and I need to utilize the preouts. Infact that is the biggest reason I wanted it. I wanted to have a preouts for everything while still being able to power my stuff. However money has been tight. And considering I got this receiver for $50 brand new out of the box on craigslist, its a good deal. Aside from the heating issue which is a manufacturers defect. I love my equipment... But I also use it for what its rated for. However after you guy's suggestions (even tho it always sounds beautiful at high volumes...) I will turn it down till I have an amp. Speaking of which, who can help me save this beautiful receiver and spec me out an amp worthy of these speakers?
P.S. After actually calculating the volume level, it was only at about 65%. Not 85%...big difference I know.

CoolJazz

I'm wondering if among the things you're missing here is that a, let's say, 200 watt receiver isn't doing 200 watts when the volume control is at 100%.

Where the volume control is will be related to how much level is coming in and how much gain the amp design inherently has. A design may do doing all it's capable watts rating when at any given point on the gain. And it's very dependant on how much voltage is coming in from what is feeding it.

If your amp and your speakers had arms, they were waving the white flag. And you're just abusing them when you run them to the point of being blazing hot. That's their best way of telling you "too much"!

And if that's what you're saying, you should never ever run a test tone like that at a crazy high level into any speaker. They're made for music not to act as a dog whistle.

Please, please treat your equipment with respect and let it entertain you. Abuse is not the answer. It might fight back!

CJ

Tucker_Z

The Marantz has an issue already. I'm merely using it and it heats up beyond what it should if it were not defected. Its a common problem for this receiver. And are you also trying to tell me that my Pioneer VSX-403 can power the RTAs without breaking a sweat and at a higher gain than this Marantz. That just seems off to me. I am in no way actually pushing it to it's limits. It gets very warm just being on-when it isn't even amplifying anything...

ROHfan

Sounds like you need an external amplifier that has enough power to be driven. Get a good AVR with preouts and a proper amp to drive your speakers. You've gotten plenty of sage feedback in this thread, now go out and do the right thing by your gear.