Definitely KT88s. 6550s: Edgy, dynamic, analyical. EL34s: Lush, loose, soft. The KT88 blends the best of the 6550 and EL34: liquid midrange with enough low-end punch to match the high-end air. In short the best balance. The KT90 does not work well in Jadis products except the JA-100 and Orchestra Reference which have proprietary output transformers specifically wound for the KT90. My reference JA-100s sound like the perfect transistor; very hard to beat. But for some reason I'm looking for a pair of JA-80s and some Gold Lions.
JADIS JA80 with 6550 or KT 88 or KT90 ?
My Jadis JA80 was built in April 1999 and came equiped from the factory with eight 6550 valves.
Before deciding to buy a new set of tubes, I would like to know some opinions about the advantage or inconvenience of using the KT 88 or the KT 90 tubes in my JA80.
Is there any experience of using these tubes (KT 88 or KT 90) in an amplifier designed from the factory to work with 6550 tubes?
Many thanks for your cooperation.
Before deciding to buy a new set of tubes, I would like to know some opinions about the advantage or inconvenience of using the KT 88 or the KT 90 tubes in my JA80.
Is there any experience of using these tubes (KT 88 or KT 90) in an amplifier designed from the factory to work with 6550 tubes?
Many thanks for your cooperation.