Audio Research Ref: CD8

I am in the process of having my CD 7 power supply upgraded and was thinking about changing the 5881 tube for something like the Gold Lion KT66 or the Tungsol 6L6.

Would anyone be able to confirm if either of these would fit in the unit?

Many Thanks

I know you think that the CD7 had an upgrade in power supply. In fact it was a revision due to problem with the two regulator tubes.

The problem can be noticed when you use the unit via SE outputs if you increase the volume you can here a huge hum.

Revision 5 kit killed the hum, but also killed the sound quality. Now the revision 7 (5881 tube) brought the sound back but the also, the hum, after some use.

I had my unit upgraded. And now the hum is back. I will call ARC I think they will have to change all units again, problably using a 6550 like in CD8.

So I ask you to test your units and call ARC if you have a hum in SE output.

Gave up on CD7, after 2 units and a lot of power supply problems upgrades. My last unit showed the SE Hum again even with the 5881 tube.

I went to a CD8, 3 hours only, in it for now. I will post about it later.

Anyone have any further observations/updates? Thanks!

Hello Wstill,

I have a CD7 and am considering upgrading the power supply and see that you have done the same, how much did this cost?

Regards,

Paul Serwin