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Power tubes as drivers -- Line Magnetic

I just purchased a LM 518 IA, which is a 22 watt SET integrated using 845 tubes. The amp uses 2 6L6 as drivers and 12ax7 for input.

I'm picking up the amp this week, and although I haven't seen the user manual yet, From what I can gather, virtually any power tetrode or pentode, including EL-34, KT-88, 6L6 and 6V6 can be used as a driver in this amp. Of course that means I'm getting ready to try a buncha tubes.

My current thought is to pick up decent, but not expensive, current production samples of the various tubes (probably all made by the same manufacturer to maintain some control) so I can get a handle on which sound I prefer most, then move on to more expensive and probably NOS versions of those tubes I like best. Just checking in with the community for reality check on if this makes sense to anyone else.

Also, I've seen on various tube sellers sites reference to "this (noisy/micro phonic) tube is only suitable for use in a driver stage . . . ." Can I infer from this that I can get away with slightly dodgy driver tubes and thus buy really fancy schmancy tubes in low grade and still achieve good results?

Will appreciate your thoughts.

D
dkidknow
rleff
1,065 posts
 
What is the return policy on those dealers that would not allow a home audition?
If they would allow a return if the match was not what you wanted along with a refund and not store credit I might go for the purchase and give it a try.
I can't believe dealers that would not allow a home audition of higher end gear; to me the wrong business model.
These amps look very interesting to me as well.
jslateiv
64 posts
 
I have found that the 5751 (GE, JG5751 Blackplate '57) is a phenomenal input tube in this amp. Very smooth, great extension, none of the 'glassiness' that I heard with the stock tube. I also tried a JAN Sylvania 12ax7 that was better than stock but not near as good as the 5751. So far I am preferring 6L6 & 6V6 types over EL34 or 6P3P. I fing the 6L6 and 6V6 to be very similar with the 6L6 to have a little better bass presence. The stock 6P3P was a bit veiled across the entire freq. spectrum compared to these other 2 types.
dodger4
61 posts
 
The Pxvane 845 II ,12ax7 II and the 6ca7 II sent my 518 line magnetic to heaven
jayh31
86 posts
 
I recently auditioned the LM 518 mated to a pair of Harbeth 7s, the same speaker Tim used in his excellent review. It sounded absolutely horrible. Congested, bloated, dull, slow, and completely devoid of any dynamics. Everything from the lower mids down was a complete mess. The dealer was apologetic and as he said, "embarrassed" that I set a Saturday aside to drive the considerable distance to hear (and not hear) this highly regarded amp that we both agreed was unlistenable. I was really wanting to love this amp and was sorely disappointed when it wasn't even close. The dealer attributed the poor sound to what did seem to be a rather pronounced echo in his listening room, however, it sounded so poorly, I wasn't convinced that could be the primary reason and declined his generous in-home audition offer. As a consequence I've since ordered the Coincident 845 SE and can't say that based on my experience, I could recommend the 518 to anyone.
dennis_the_menace's avatar
dennis_the_menace
467 posts
 
In my experience Harbeth's sound much better with solid state. When paired with warmer sounding tubes they can sound dull, veiled and congested. IMHO YMMV
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