jerome DAO wrote:

Hi,
I am really a neophyte.
I just bought an old Phase Linear 400 Series 2.
The problem is : there's no off-on button. To switch off/ on ,it must
hurt the loud speakers. As pre-amp, I have a Harman Kardon AP 2500
Please tell me what to do?
Thanks

--
jerome DAO

If the preamp has a heavy-duty, "switched" jack for the amp
on its backside you could use the preamp to control the
on/off function.

Also, you could plug the amp or even the whole system into a
switched power strip and cut things off that way. Cutting
power to the amp will not hurt the speakers.

Howard Ferstler