New Heathkit AS101 owner - First post.

[Earl K]

So the blue is without the HF compensation circuit, the green is with... It doesn't seemed to have helped.

But to tell you the truth, I'm more concerned with the lack of bass response. Where the heck is 50-500Hz? Is this normal, or are my 416As are tired?

(i) I can assure you, that ( when you first listened to your speakers 4 weeks ago ) if they had even remotely resembled this latest test trace , you would have concluded that your new speakers had blown woofers and been asking the forum for help on how to fix them .
- Since you've never ( till now ) mentioned such a total lack of woofer action ( from your previous listening sessions ) , the logical assumption is that your measurement technique simply isn't allowing the woofer to be picked up into the test mic ( or something similar ) .

(ii) It's always possible that this new "T-Pad" is miswired into the circuit somehow ( maybe the original variable Lpad was wired backwards ) . I'd suggest bypassing that ( stock ) variable pad and trying again .