Calling Al Rotel RA1520 owners - Overheating issues?

[Venom]

Hi Folks,

I am having issues with my Rotel RA150. It is overheating. The amp is connected to B&W CM9s and as you can see on the video below volume knob is less then half.

Amp is 2 months old and sitting on top of my Tv unit. Air circulation is not restricted.

Just to confirm that this is temperature related used a fan and plays for hours with no problems.

Room temp is around 27 C degrees.

In your experience, Is this normal or should I start calling the shop for an RMA?

[video=youtube;eoc-75fnP_k]http://www.youtube.com/watch?feature=player_embedded&v=eoc-75fnP_k[/video]

 

[TLS Guy]

Hi Folks,

I am having issues with my Rotel RA150. It is overheating. The amp is connected to B&W CM9s and as you can see on the video below volume knob is less then half.

Amp is 2 months old and sitting on top of my Tv unit. Air circulation is not restricted.

Just to confirm that this is temperature related used a fan and plays for hours with no problems.

Room temp is around 27 C degrees.

In your experience, Is this normal or should I start calling the shop for an RMA?

[video=youtube;eoc-75fnP_k]http://www.youtube.com/watch?feature=player_embedded&v=eoc-75fnP_k[/video]

I think you have the wrong speakers and wrong music for that amp.

You are playing a highly compressed program where nothing gets a break.

The speakers though nominal 8 ohm, which means nothing, have a minimum impedance of 3 ohms. A much better guide to knowing the real impedance is the minimum impedance + 10%, which puts those speakers below four ohms. That is pretty typical for B & W speakers which in general require very muscular amplification.

That is a low powered amp with no four ohm specification.

I would be certain your problem is a mismatch between speakers, program desired spl. and your amp. Doing what you are doing fan or no fan, I don't think that amp will be long for this world and will be on a fast route to the recycling center.

 

[Venom]

Thanks for you reply. I'm new to HIFI an d by no means an expert. I used that music on purpose to test the amp. (not my cup of tea btw) I know that sounds horrible but mic camera is not the best.

Amp plays for hours very very loud and with no distortion when a fan is blowing

What I'm trying to confirm is if the Rotel RA1520 is prone to overheating or mine is faulty. Or maybe as you said, this combination is not compatible (although this is what the store recommended due to B&W and Rotel being parent companies, apparently B&W speakers are teste with Rotels)

 

[TLS Guy]

Thanks for you reply. I'm new to HIFI an d by no means an expert. I used that music on purpose to test the amp. (not my cup of tea btw) I know that sounds horrible but mic camera is not the best.

Amp plays for hours very very loud and with no distortion when a fan is blowing

What I'm trying to confirm is if the Rotel RA1520 is prone to overheating or mine is faulty. Or maybe as you said, this combination is not compatible (although this is what the store recommended due to B&W and Rotel being parent companies, apparently B&W speakers are teste with Rotels)

That may be but B & W speakers are notorious for being power hungry and you have a small amp, with no 4 ohm rating.

For those speakers a small integrated amp is not going to cut it, unless you listen at very low volumes.

You are going to need a preamp and separate power amp in the 250 to 300 watt per channel class into four ohms.

If you want to keep that amp then you need more sensitive and efficient speakers with no large impedance dips or difficult phase angles between voltage and current.

I'm certain if you use that combination at the levels you want, you are going to destroy that amp. Basically that amp is a little British integrated, of which a great number have appeared over the years.

UK homes and rooms in the main are much smaller than in the US, and the vast majority of homes have one or more shared walls. A very high proportion of these homes were built around 1900, and acoustic isolation was not an issue. If your annoy your neighbor with your sound rig, the police will confiscate it, and you have no redress. So power demands here and there are very different. For this reason British integrated amps have never had the appeal in the US that they have had in Europe. In Holland and Denmark for instance these issues of creating a nuisance are even more acute.

 

[mike c]

is this 2.0?

try an easier to drive speaker (one that does not dip to 3 ohms). if it still does it, it might be the amplifier.

on the other hand, you could add a subwoofer, use the built in highpass to filter the lowbass from your main speakers. (pre-out main in)

 

[Venom]

is this 2.0?

try an easier to drive speaker (one that does not dip to 3 ohms). if it still does it, it might be the amplifier.

on the other hand, you could add a subwoofer, use the built in highpass to filter the lowbass from your main speakers. (pre-out main in)

How can I check the version? Good idea, I'll test with some wharfedale diamond 9.1 that happen to have to confirm...

 

[mike c]

How can I check the version? Good idea, I'll test with some wharfedale diamond 9.1 that happen to have to confirm...

sorry, when i said 2.0 ... i meant if this was 2 channel, as opposed to 2.1 channel

 

[Venom]

Yes stereo 2.0. No sub.

 

[TLS Guy]

is this 2.0?

try an easier to drive speaker (one that does not dip to 3 ohms). if it still does it, it might be the amplifier.

on the other hand, you could add a subwoofer, use the built in highpass to filter the lowbass from your main speakers. (pre-out main in)

I have looked through the manual. That unit boasts 50 years of experience with integrated amps. Translation: - 50 years out of date. In my view more than that from decoding the phraseology.

There is no bass management, but it does have pre outs.

It has A and B speakers, but recommends against using A + B at the same time unless speakers are truly 8 ohm. It points out that 8 ohm speakers may in fact not be and have performance dips.

The output devices have dual protection and monitor the heat of the output devices and current. They state that impedance dips can trigger protection.

There is no four ohm power rating.

Working backwards from a max current consumption of 300 watts, that unit being A/B bias is not going to increase power as impedance drops. I would bet that unit struggles to deliver 30 watts to those speakers before the protection cuts in.

His solution is to get a beefy 2 channel power amp and plug in into the pre outs. That will solve his problem.

B & W and Rotel may be the same outfit, but that amp and his speakers are far from a match made in Heaven no matter what his dealer told him. As usual dealers don't know much except how to sell funny wire.

OP did they sell you "funny wire" with these units?

 

[anamorphic96]

Rotel sometimes does not state a 4-ohm rating. For whatever reason I don't know. But the RB-1080 (200w) I owned for two years did not have this in the manual as well. Just an 8 ohm rating. But did state 4ohm minimum next to the speaker terminals. Just like the RA-1520 does. After contacting Rotel for a 4 ohm rating on my amp I was surprised to find out it put out over 300 watt per channel. My RB-1080 ran quite hot as well. Even at idol. From my understanding Rotel amps are biased on the high side causing the extra heat. Onkyo's amps are the same way and run rather warm.

The RA-1520 is 4ohm capable and probably puts out about 90-100 watts per channel into a 4ohm load. This amp is essentially the RA-1062/RA-1060. This 60 watt model has been around for many years. OP should contact Rotel for some real numbers.

Rotel tends to be conservative in power ratings. They also have a habit of sometimes presenting specs that can make one skeptical.

 

[mike c]

right. i don't know why my memory of the 1520 has pre-out main-ins.

i would return the amp for another.

rotel has been known to spec at least 50% more output at 4ohms compared to their 8ohm output (on bench tests, they usually exceed their specs)

 

[Venom]

right. i don't know why my memory of the 1520 has pre-out main-ins.

i would return the amp for another.

rotel has been known to spec at least 50% more output at 4ohms compared to their 8ohm output (on bench tests, they usually exceed their specs)

I tried several integrated amps at the store before buying and although the Rotel 1520 was lower on paper specs was the best one driving speakers... It was a lot louder and clearer than the Rega brio r and the marantz 7004.

Thanks for the info guys. Called the dealer already and i'm taking the amp to them tomorrow, ill keep you posted

 

[AuditMan1]

I am also having overheating problems with my Rotel RA 150. My speakers are Klipsch CF2's. Can't understand why as the Klipsch are highly efficient speakers. Any help will be appreciated. Thanks.

 

[TLS Guy]

I am also having overheating problems with my Rotel RA 150. My speakers are Klipsch CF2's. Can't understand why as the Klipsch are highly efficient speakers. Any help will be appreciated. Thanks.

Even though sensitive, Klipsch speakers are notorious for dropping impedance in the power range. I cant find an impedance curve for your speakers, but I can't find a Klipsch speaker with two woofers that is not essentially a 3 ohm speaker.

Your solution is to play at reduced volume, or get a bigger amp.

Remember sensitivity ratings are NOT efficiency ratings, and do not tell you directly how much electric power a speaker converts into acoustic energy.

 

[PENG]

The RA-1520 is 4ohm capable and probably puts out about 90-100 watts per channel into a 4ohm load. This amp is essentially the RA-1062/RA-1060.

You are probably right, 80W-90W would be my guess, but will certainly overheat at 80W into 4 ohm and tripped the protection circuit even at 60W 4 ohms if playing highly compressed music, very marginal for those B&Ws especially for compressed music as TLS Guy pointed out. You can laugh at it but I am going to say the OP is better off with a cheap 7.1AVR such as a discontinued Denon 3311, 3312, 4310, Yamaha 1010 etc., as those has a power supply rated at least twice as high as the baby Rotel, all for the use of 2 channel. Those AVR have been bench tested by HTM and others to put out over 200W 4 ohm and should have no trouble with 80W into 4 ohm even for compressed music. By the time he add a power amp to the integrated it will cost much more than a mid range AVR.