problem

[Ricky]

Hi guys. My name is Ricky. I am an acoustic engineer but I have decided to branch out in to electronics.

My problem is this!!!. I have designed and built a valve pre that sounds great into a linear amplifier but I need toproduce 6.6 p.t.p into a class D power amplifier. I know I need a cathode follower but has anyone any ideas how I do this???. The load impedance is 10Kohms. I need a feed at around 500 to 1K. HELP???. Loudspeakers are easy compared with this!.

[Cal Weldon]

Hi Ricky,

Welcome to the forums.

If you haven't already, I recommend you post this question over in the Tubes or Class D section. You'll probably get a better response there.

Cal

Edit: Thanks leadbelly

[leadbelly]

Originally posted by Ricky
My problem is this!!!. I have designed and built a valve pre that sounds great into a linear amplifier but I need toproduce 6.6 p.t.p into a class D power amplifier. I know I need a cathode follower but has anyone any ideas how I do this???. The load impedance is 10Kohms. I need a feed at around 500 to 1K.

Probably better off in the Tube forum as you are asking about tubes....but I don't really understand your problem. You need to feed a Class D power amp with 6.6V PTP and a 10K load impedance? Just the voltage stage in your tube pre should be able to handle that alone. Why do you need to add a cathode follower to get a lower impedance output?

[Ricky]

Thanksfor the reply. Although not the greatest Electronics engineer in the world, logical thinking told me that I should have been able to do this off the pre board but you get told all sorts of things whenyou ask questions, don't you?.

Many thanks.

Ricky.

[Ricky]

[Hi.

First of all, many thanks for your input. The reason for the cathode follower is that there are 5 input stages of varying gain. These in turn go via the selector switch to a summing stage. I don't like forever turning the volume knogb up and down. Everything should be the same at a refernce frequency ( i.e. 1KHz).

The pre is finished, the power amp is finished and went out on audition yesterday. The results were incredible. The sytem used was mine, plus a Copland CD player and a pair of Pro-ac Response 3.8's. Normally, this guy gives you 10 minutes. I had 2 hours and I've got to go back because "I've got something very special (?????). Can't be that far wrong. Doesn't sound like a valve, a linear or a class D. Something on it's own. I'm chuffed. Thanks again.

Ricky.