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Parasound JC-1 Heat Dissipation

I am looking at purchasing a pair of Parasound JC-1 monoblocks based on the excellent feedback both here and other places. After a flurry of upgrades this year, the power amplifier is the next piece of equipment to upgrade. I have made the decision to stick with solid state since I like keeping my system powered up at all times and the Wilson Benesch loudspeakers like lots of power.

My current system:
- TRL Marantz SA-14 SACD player
- Conrad-Johnson 17LS tube preamplifier, Amperex Holland 60s tubes
- Rotel RMB-1095 5X200W multichannel power amplifier
- Wilson Benesch Discovery loudspeakers

My only concern with the JC-1s is the amount of heat generated since they run the first 25/10 watts in Class A mode and consume 250W in idle mode. This is of concern especially during the summer months.

My audio room is sealed, 16.5ft X 12.5ft X 8ft, and is located on the main floor of my house.

Also wondering if I can reduce heat dissipation if I set the bias switch to low (10W Class A) and only switch it to high during listening sessions. If I do this, does it take time to warm up to fully take advantage of 25W potential?

Also if I have a fan blowing on the power amplifiers outside of listening sessions, is this of any use?

Any feedback from others who have a pair of JC-1s in a similar room is appreciated.

Also the match between the JC-1s and the C-J preamplifier which only has unbalanced output.
shuang

Showing 2 responses by shuang

shuang OP
21 posts
 
Thanks for the input. Sounds like I will have to pass on the JC-1s given my room size.
shuang OP
21 posts
 
The Plinius SA-250 looks like a good unit but it also has a class A mode.

However won't it have the same problem as the Parasound JC-1s? Since it runs in Class A mode to sound its very best.

Is it practical to leave it in AB mode then switch to class A mode for critical listening. Once in class A mode, how quickly will it heat up the room?

From the Plinius manual.

BIAS A: This position provides a true Class A bias to the output stage therefore ensuring the optimum performance of the amplifier during all listening events. Class A amplifiers run hotter than Class AB amplifiers, hence our specially designed and distinctive heat sinks. Operating the amplifier in BIAS A necessitates two precautions that should be observed.

1. On switching to BIAS A, the temperature of the amplifier will quickly increase and the amplifier will become quite hot. Once again we remind you to ensure that you have left adequate space around the amplifier for ventilation. Ensure that no objects are resting on the amplifier and check that the heat sink (cooling fins) are not obstructed in any way.

2. The current required from the mains supply in BIAS A is approximately 1,000 watts, similar to a small electric heater. The amplifier should not be connected to a wall outlet that is shared with other heavy current appliances such as heaters or electric motors.
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