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Replacing 12AU7 tubes in a Prima Luna Dialogue integrated amp

Bought the until about 2-3 years ago, as the core of a new system (Dynaudio Excite 34X speakers, Rega 8 w/ Apheta 2 cartridge, Rega Aria phono amp, Oppo BDP-105D for CDs plus video).

Very happy with the system.

One of the 12AU7's crapped out, so buying a new set.  Tried pulling out the bad one, and its really, really tight in the socket.  Never swapped these out before, not sure if the just pull up, or have some cam lock to hold them in. Afraid to force it, possibly break something on the socket, it sure seems very very snug.

Sound normal?  Just keep pulling up until it moves, or ? 

Any tips, tricks or info appreciated.  (and yes, I am using the gloves PL provided for all handling of amp items.)

Richard
dalorzof
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samzx12
1,220 posts
 
Oh I definitely understand trying something new and didn't realize you were in Australia.  I just couldn't warm up to the 120 at all. Had great bass, drive and separation however, the mids were dry and couldn't tune it out with Mullards. Your mileage may vary but I would look into a Gold Lion KT-88 or the Tung Sol KT150. The 150's tone wise kill the 120 and sound a bit more relaxed like a EL34.  Of course my Dialogue Premium was designed around the EL34 even though it can utilize just about any power tube so your amp may sound better with the 120.  Just read reviews and trust your gut :)

P.S. Andy at Vintage Tube Services does know his tubes also. I dealt with him just a few years ago. Super nice guy. 

Sam
dalorzof OP
9 posts
 
Sorry, should have noted my location.  Things that are commonplace or at least available with a little effort in the US can be unobtanium here.  Or just incredibly expensive. Small markets.

Thanks for the tip on the KT-120 and KT-150, another case where bigger is not always better.

Will try to call Vintage Tube next week.
dalorzof OP
9 posts
 
Found these locally,

A friend has Electro Harmonix and is happy, I've herad good things about the Gold Loin.

Recommendations?  All are similar prices, except the Golden Lion which are about twice the cost of the others.

Need to contact the shop for availability next week, everything is closed here until Tuesday.

12AU7 Ecc82 Electro Harmonix twin triode

12AU7 ECC82 Electro Harmonix gold pin

12AU7 ECC82 JJ Electronics twin triode

12AU7 Genalex Gold Lion gold pin Also known as B749 / ECC82

12AU7W Tung Sol twin triode
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samzx12
1,220 posts
 
I'm not familiar with any of those tubes but my guess the Gold Lions would be better and not because they are more expensive.  I used to have some Tung Sol 12AX7 and they sounded nice so I would think the 12AU version would also. 
dalorzof OP
9 posts
 
Thanks.  They only had 5 Gold Lions, so I bought two of them to test your "replace the front two with better ones" comment.  And a set of the ElectroHarmonix gold pins.  

Try a couple different configurations and see if there is noticeable tonal change, to me...
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