Rotel Amp (used) gets really warm...what to do?

[TedNeu]

I bought a ROTEL INTEGRATED AMPLIFIER RA-960BX earlier in 2016.

This is a model from the late 1990's. It has a small chassis so maybe it doesn't distribute heat too well.

When I received the amp it was quite dirty inside. The controls were scratchy and the sound was in/out/on/off. After trying to clean it myself, I had it professionally serviced.

(Since the E-Bay seller had assured me it was fully tested and worked fine, I told him I would send it back. He instead said "keep it" and refunded my 175 dollars.)

The amp sounds fine now. I would say that it has a warm, full sound. But that warmth of the amp itself is odd to me.

Does this matter? It puts out heat even when not cranking tunes, so I tend to shut it off, even if I'm just stepping out for 1/2 hour or so.

 

[willyrover]

It's not unusual for an amp to get warm while idling and if it was professionally serviced they should have set the bias correctly.

That model also looks to have a lot of heatsink happening in the center portion of the unit.

If you have a multimeter you can check the bias (idle current) fairly easily. Here are the instructions from the service manual. Test points are located between the heatsink fins.

 

[TellMeWhy]

I bought a ROTEL INTEGRATED AMPLIFIER RA-960BX earlier in 2016.

This is a model from the late 1990's. It has a small chassis so maybe it doesn't distribute heat too well.

When I received the amp it was quite dirty inside. The controls were scratchy and the sound was in/out/on/off. After trying to clean it myself, I had it professionally serviced.

(Since the E-Bay seller had assured me it was fully tested and worked fine, I told him I would send it back. He instead said "keep it" and refunded my 175 dollars.)

The amp sounds fine now. I would say that it has a warm, full sound. But that warmth of the amp itself is odd to me.

Does this matter? It puts out heat even when not cranking tunes, so I tend to shut it off, even if I'm just stepping out for 1/2 hour or so.

I have the same problem with mine! Seems that it's quite normal for that particular model. Will check DC bias and see if that helps!

 

[KingsleyD]

I bought a ROTEL INTEGRATED AMPLIFIER RA-960BX earlier in 2016.

This is a model from the late 1990's. It has a small chassis so maybe it doesn't distribute heat too well.

When I received the amp it was quite dirty inside. The controls were scratchy and the sound was in/out/on/off. After trying to clean it myself, I had it professionally serviced.

(Since the E-Bay seller had assured me it was fully tested and worked fine, I told him I would send it back. He instead said "keep it" and refunded my 175 dollars.)

The amp sounds fine now. I would say that it has a warm, full sound. But that warmth of the amp itself is odd to me.

Does this matter? It puts out heat even when not cranking tunes, so I tend to shut it off, even if I'm just stepping out for 1/2 hour or so.

I have just purchased one (RA-960BX), last week, and I was surprised at its heat levels after sitting for 10 minutes with nothing playing. The only obvious signs inside are the four large resistors by the heat sink and the paper wrapping has shedded due to the heat. I guess. There is some brown residue around some of the caps but not sure if this is leakage or not.
Anyway it sounds great with no performance issues so far. Time will tell.

 

[whoaru99]

More than likely (playing the odds here since there are no pictures) the stuff around the caps is just glue.

If you follow the advice to check bias just be careful. One slip and you could have an amplifier than needs a bunch of parts and a repairman.

 

[ev13wt]

What is "warm". Like in degrees? Burning your skin warm? "Feels hot?"

 

[whoaru99]

Bear in mind the original "really warm" post was 9 months ago...