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Tube amp forethought

Hello, im researching my retirement two ch audio system and tube amps are in the forefront of my “wants” my plan will be a pair of QUAD ESL’s not sure which just yet

What do i need to know about maintaining a tube amp, like a AudioResearch 120 for starters or other tube amps. Biasing is totally new to me. Tube life and modes (triode, Pentode, UltraLinear) all foreign to me.

im a 40 year hobbiest so im pretty versed, this is just an unknown territory for me, thanx guys !

kgveteran
roberjerman
4,319 posts
 
@jperry +1 - I used a Bedini 25/25 with my Quad 57's for years. The only tube amps I found comparable were the Futterman OTL's (I still have 3). An alternative choice would be a nicely restored Quad 303. The 57's are voltage-limited. They will be damaged with more than 20 volts (50 watts). 
roberjerman
4,319 posts
 
If you are still insistent on a tube amp, the Dynaco ST 70 (either vintage or new) is a good match for the 57's.
bdp24's avatar
bdp24
9,981 posts
 
I was yet another QUAD ESL/Bedini 25/25 user for years, but if and when I put my QUADS back into service it will be with a Music Reference RM-10. Roger Modjeski used the QUAD as his load when designing that amp. He has offered in in two versions: as a 35/35w Class-A/B, and as a 25/25w Class-A.
roberjerman
4,319 posts
 
@bdp24  +1 Sounds good!
pehare's avatar
pehare
837 posts
 
+2 for the Music Reference RM10 MkII.  I've enjoyed one as my primary amp since 2011 w/no issues - in fact never shorted or even worn out a tube (knock wood).  I swapped tubes a couple times to hear if they were wearing out and had them tested.  Biasing is easy, rock steady and never needs adjusting.  The newer 25 watt version is self-biasing.  I owned 5 tube amps prior and this is my keeper.  Take the plunge!
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