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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 again for everyones thoughts. Now the struggle is finding any integrated amps that will satisfy my friend (based on his loving the sound of the 518ia). It clearly needs to be something  that won't overheat him, and the room, is available for  $3-3500.00, used, and is somehow comparable to the sound of the Line Magnetics.

I've already discussed it with several audiophile friends that are familiar with the sound of the 518ia, and they too, are having difficulty coming up with something that meets all of the above. One initially suggested a Unison S6, which does sound like a real possibility, but I think that might  also present a heating issue. Its a Class A amp, only moderately powered, but in the Stereophile review, John Marks notes that, " The S6 performed flawlessly, though it did throw off a lot of heat.". That surprises me since it uses EL34 tubes. 
almarg's avatar
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almarg
8,673 posts
 
The Unison S6 has a specified power consumption of "265 VA max." Given that it is a class A design that probably means a continuous draw of not a great deal less than 265 watts, which in turn is not greatly less than the 320 watts drawn by the LM-518ia.

An EL34 requires close to 10 watts just to heat the filament, and I'm guessing that in this design each of the six EL34's consumes something like 25 watts in total. So that's 150 watts just for the power tubes, plus additional consumption by the power supply, the small signal tubes, and other circuitry.

I don't have a solution to propose, but as Charles and I stated earlier perhaps the answer involves going to a less powerful amp than the ones that have been mentioned.

Good luck. Regards,
-- Al 
charles1dad's avatar
charles1dad
6,996 posts
 
Nightfall
Unison Research is an Italian company that has a reputation for good sounding tube amplifiers. My suspicion is that it will fall in somewhere between the Prima Luna (class A/B push pull) and the LM 518a (class A SET) . The S6 model is class A and parallel SET with 3 el 34 per channel.

I bet this amplifier sounds really good given the design, circuit and topology. Don’t know if it will equal what your friend heard with the 518a but you never know until you’ve actually listened . As Al noted heat output is still a concern. I sympathize with your fiend, he has good taste/ears but limiting circumstances.
Charles
charles1dad's avatar
charles1dad
6,996 posts
 
Nightfall,
Even el 34s will generate noticeable heat if they’re operating in class A. Just goes with the territory if the amplifier is rated at say 20 watts and higher. I had a borrowed First Watt S.I.T push pull amplifier (35 watts class A) for several weeks and if ran hotter than my 8 watt  300b SET mono blocks.

Class D amplifiers would be an obvious solution if your fiend can find one with sound he could live with. Not sure if he’ll find one that mimics the LM 518a. Well executed class A is hard to match let alone beat.
Charles
nightfall OP
133 posts
 
Al, and Charles, thanks to both of you for the input. I agree with everything you both had to say. The Unison is an intriguing option, but I suspect may still be too hot to be placed so close to my friends seating area, etc. 

He needs 25-35wpc, ideally. An amp that puts out a bit less but plays above its level, in terms of delivering power might also work. 

Charles, I find it very interesting that the First Watt S.I.T.  ran that hot. Was it the fabled S.I.T. 1, or the S.I.T. 2? Granted, some of Nelson's designs, despite being solid state, can get seriously, seriously hot. I was auditioning several sets of speakers for about 90 minutes last year with a friend. The dealer had us in a huge showroom (literally 100x50. He was using  a pair of Pass X600.8's, which aren't even pure class A, except for the first 100 watts or so (or something like that). Even in a room that large, by the end of the audition, we were sitting there with our shirts completely stuck to us,and sweating liberally from our heads! My friend actually had to go home to shower before meeting a group of us for dinner! 
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