Which Amp Runs Cooler : RB-980BX or RB-1070 ?

[FernandoF]

I've recently purchased a Rotel RSX-1056 and got surprised at how hot it runs ! Ok, I have Dynaudio 52SE's which are 4 ohms and 86dB/w.m inefficient, but I wasn't expecting so much heat to be generated. The receiver is placed on the top of a very wide rack, so there is nothing obstructing the covers. I don't think I'm pushing the receiver too hard either (volume 50~55, 60 at the most). Nevertheless, the righthand half of the top cover gets almost too hot to touch...

I've been considering adding an external amp to run the front Dynaudios, and the heat issue is making me think about it even more. I am wondering whether owners can comment on the RB-980BX and/or RB-1070 in terms of heat generation. Which one should I expect to run cooler ?

Thanks in advance for any feedback.

[miner]

I have a RB-1070 that has a RC-1070 on top of it - no heat whatsoever. They drive B&W N804.

[FernandoF]

Thanks Miner, that is good news !

[DL86]

From what I heard, the newer model amps have better heat management. So I guess the rb-1070 will run cooler.

[FernandoF]

Thanks, DL86. That's 2 votes for the 1070 so far.

Any comments on the 1056 running hot would also be appreciated !

[DL86]

I think its normal for the 1056 to run that hot. Same case with my rb-1080 you could cook an egg on it when I'm playing it loud. Its on the top shelf with free air all around it.

[FernandoF]

Thanks a lot, DL86.

In fact this morning I tested the receiver with B&W 601's (which are nominally 8 ohms) and it got as hot as with the Dynaudios, so the "issue" is definitely not related to my speakers.

I'll send a message to Rotel asking about the expected heat generation for the 1056, and will post their answer here at the forum.

In the meantime, if other owners of the 1056 could confirm that it indeed runs hot, that will be highly appreciated.

Regards,

Fernando

[Stev]

I have the 1056 running 4 ohm speakers and it doesnt seem to get too hot. These things are relative. I had a 2 x HK635's before the 1056 and compared to them the 1056 doesnt break a sweat.

[FernandoF]

I'll send a message to Rotel asking about the expected heat generation for the 1056, and will post their answer here at the forum.

This is the reply I got from Rotel with regards to the 1056 getting hotter than what I was expecting :

"This amplifier will run hotter that normal receivers. This is because we are running this amplifier at a higher bias rate than average receivers. I would still like you to explain your situation to your dealer. They can make a better indication if this unit needs to be replaced or serviced.

"Transistors are biased so that they do not have to be turned on for all the way off. This means that even though you have your volume down there is a small amount of wattage produced form the receiver/amplifier. Usually higher bias amplifier sound better because of this. That is why some Audiophile people will leave there amplifier On all the time so their amplifiers are always warm.

"Basically, this amplifier is running hotter than normal, but sounds better than any receiver in its class."

[Foxman]

My RSP-1066 has always gotten hotter than I would have guessed. I have never had any issues with my RMB-1075 or 1050 which I have one over the other seperated by the width of a 2x4 for ventalation.

[eelco74]

I own a RB-981, wich is a upgraded RB-980 and has different faceplate. The RB-1070 seems to be almost identical. Neither of them run hot, only a little warm at most.

I had a stack of an RB-981, RC972 and RCD-975. That was no problem.

My RSP-1068 rus pretty hot though. Not too hot to touch, but if you would add the heat of the poweramp...

[FernandoF]

Thanks a lot for your input folks, this forum is really great !

From the heat I've seen with the 1056 I was expecting the power amps to run REALLY hot, but apparently it doesn't work like that. It is interesting to learn that the processors (1066, 1068 ) run pretty hot as well. The power consumption of the 1068 are mere 40W...

I am a little bit disappointed though. After extensively auditioning side-by-side (at a store, during my trip to the US) the Rotel receiver against a Denon 3806, with the same speakers I own, and hearing how much better the 1056 sounded, I was expecting a great improvement by replacing my old Denon 1804 with the 1056. Ok, the Rotel may still need some break-in time (I've installed it just 4 days ago), but the difference I've been hearing between them is rather subtle so far.

I've managed to hook them up adequately and I've been "blind testing myself" for the past couple of days, and to my own surprise sometimes I "vote" for the 1804 ! I don't know what is happening... could it be that my room acoustics or my source (for now a Pioneer DV-655A, obviously the weak link) are limiting the potential improvement the 1056 might bring to my system ?

The money I've invested on the 1056 is significant for me, and it doesn't seem to be well justified so far. I'm afraid of putting more money on an external amp or on a better CD player and getting frustated again. It's SO important to audition new gear at home, and unfortunatelly I can't do that...

Any ideas ?

[DL86]

Just wait a little bit until the amp breaks in. I upgraded from an onkyo tx-sr501 to an rb-1080 and yamaha rx-v657 pre and when I first turned it on I thought the tx-sr501 sounded better. After a few days I was gob smacked how much better the new combo sounded.

[millenniumrx2]

my rb-990 runs cool

[tomm]

my amp runs v/hot but it is runing 4 ohm speakers.

[FernandoF]

Well folks,

I've just won an auction on eBay for an used Rotel RB-980BX. I'll be able to install it in 3 weeks only, but hopefully it will drive my Dynaudio 52SE's better than the 1056 alone. Anyway, it's done now.

Maybe it is just a little bit of extra power that my system needs. I'm aware that the 980BX may not represent a huge advantage over the 1056, but that was what I could afford at this time. At least the fronts will be driven by a dedicated amplifier, and the receiver will have an easier time running only the 42C and 3 small satellites.

I can't wait to just sit down, relax, enjoy my new system, and send the stress from these past few days away. That is, in 3 weeks...

Regards,

Fernando