Cary Rocket 88R bias setting with EL34 tubes?


Hi All,
I have & enjoy greatly a Cary 88R 'Rocket' tube amp combined with a Cary SLP98P preamp, Wireworld Gold Eclipse cables, & Harbeth 7es-2 speakers.
The amps output tubes are Svetlana (New Sensor) 6550, which are quiet muscular in their presentation. As I'm seeking a more relaxed sound, I've ordered some SED EL34 (St.Petersburg) tubes & was wondering what to bias them at?
The amps owners manual states the amp can use EL34, 6550, KT66, KT77, KT88, or KT90 output tubes, but mentions only one bias setting of 200mA.
Is this the same bias setting for all these power tube types, or does the bias setting vary for each different tube type?
Many thanks in advance for any replies.

Best Regards.
halo88

Showing 1 response by genesisaudio

I own a Cary Rocket 88R, so for the record and other owners, does the 200mA apply to the KT90, KT77, KT66 and the EL-34. Secondly, from a discussion with Cary support staff (who were superb...) my understanding was the EL-34 should be set at 160mA. Is this different spec due to the fact that there is always a range, as the Rocket 88 KT-88 bias setting is a range of 195-225mA. And according to the manual "feel free to experiment".

On tube selection, the discussion seems endless. But from what I've gathered, there does seem to be a tendency for specific tubes to be symbiotic with specific amplifiers. If you own a Rocket 88 or 88R, I would love to hear what tube brand and tube types have been a happy marriage. Cheers and don't forget - "...this is heaven".