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Line Magnetic 518ia - How Much Heat Does It Produce?

Hello, and thanks for any help with this. I'm helping a very dear friend, who loves music, and good audio equipment, put together a system. He has suffered some very serious personal setbacks of late, and one of the key things he has turned to, is putting together an audio system as a means to attempt to move forward. He is trying to put together a nice audio system in what he has available, a small room.

He travels a fair bit for work, and has had two recent experiences listening to the exceptional Line Magnetic 518ia, and was blown away by it. I can guarantee you that he has heard some very good audio components, but has been captivated by the 518ia. If you have heard it, or read the reviews, you understand, as I do. That's a truly amazing piece of gear, especially for the price.

Here is my concern, Because of serious budget deficits related to his other problems,  he can only afford one of these wonderful integrated amps, used. Okay, they are available  in his price range. I have him set up with speakers and everything else to maximize the quality of his system. But, this is a Class A amp, even if relatively low wattage. He would be using this in a 10x10 room, with the integrated amp only 2.5 feet away from where he sits. There is no other available placement. Is this going to overheat him, and/or the room? 

Any input would be appreciated. If he cannot make use of this amp he loves so much, it could get very difficult to find anything else, given it's price performance capabilities. 
nightfall
nightfall OP
133 posts
 
Thanks for everyone's input. Some of you clearly understand where I am coming from, others apparently do not. Yes, all tube amps put out heat. But dependent on design, tubes, and class there is a very wide variation. For example, I was out of town recently for three weeks and loaned him my office systems PrimaLuna tube amp. He had no heat issues whatever, but felt the amp, while very nice, was not in the league of the 518 (which I agree with him on). 

The Line Magnetic is Class A, and uses some tubes that run extremely hot. Thats a very different situation than normal in the tube world. I once had the experience of using an 845 based amp, with heat output not even quite to the level of the 518ia. I used that in my office, which is 10x11, and even with the door open, and the ac running it was too hot to work in the room. I did use it for a couple months the next winter, and after an hour of use, it had raised the temperature of the entire upstairs of the house by 5 degrees. 

I'm going to have to agree that the advice from wlutke, testpilot and others. This solution won't work. Now my problem is that, given that he loves the sound of that Line Magnetic amp, how do I possibly find something comparable to it in the same price range :(
charles1dad's avatar
charles1dad
6,996 posts
 
Nightfall,
I will respectfully disagree with ozzy62 as I don’t consider this a "ridiculous " concern. Given the very small room size and close proximity to the amplifier heat output is a legitimate concern. A 300b SET amplifier (such as mine) wouldn’t be a major issue. However the 845 output tubes are an entirely different matter. These large transmission tubes generate considerable heat that will be quite noticeable in close quarters.

I certainly understand the desire to own this amplifier. 845 tubed class A SET will provide difficult to equal beautiful, palpable and natural sound.
Bottom line, significant amplifier heat output in very tight surroundings.
Charles
charles1dad's avatar
charles1dad
6,996 posts
 
There are numerous very good sounding tube push pull amplifiers using indirectly heated tubes, KT 150,129,88,el 34 etc. The DHT SET amplifiers such as The LM 518a are as your friend heard just different and sound fantastic. I know how he feels. Prima Luna is nice sounding but not the same.
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almarg's avatar
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almarg
8,673 posts
 
I agree with the conclusion that "this solution won’t work."

For a class A amp the calculation is simple. The amp is spec’d as consuming 320 watts, and given that it operates in class A virtually all of that power will be converted to heat and radiated into the room whenever the amp is powered up, regardless of whether music is being played or not. And in this case into a 10 x 10 room at a distance of only 2.5 feet from the listener. That seems to me to be completely untenable.

A small handful of those 320 watts will be sent to the speakers when music is playing, but the great majority of even those few watts will then be converted to heat by the speakers. The rest of the 320 watts will be radiated into the room by the amp.

Also, based on the specs I’ve seen for various Line Magnetic models their power consumption generally seems to be particularly high relative to their output power ratings and class of operation. In the case of the 518ia, for example, 320 watts input divided by 44 max watts of output for the two channels is a ratio of 7.3, very high even for class A operation.  Or putting it another way, 44/320 = 13.7% efficiency, very low even for class A operation.

What speakers are being used? Perhaps less power than 22 watts per channel is necessary, especially since the listening distance will be minimal?

Best of luck in this endeavor.

Regards,
-- Al
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