Still room for a big choke in there somewhere!
Indeed - have chokes, will travelâŚ
Unfortunately I think the secondary ht winding wonât have a high enough output to deploy a choke input filter effectively (not without reducing the ht voltage and output power). A CLC arrangement would still likely be better than the CRC it has now. But as pointed out above the BP supplies work well with these.
incidenhtally, i notice the input driver stage has been modified. Do you know what was done?
Apparently it was a custom build by AI, no driver stage so it only has a single e88cc buffer (or in mine reflektor 6h23n-eb)
Works really with the M7 having much less gain and very little hum.
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I donât recall that ever being done in the factory but as an idea it makes a lot of sense for high gain linestages.
Allan Wallace apparently
He was the best hardwire builder of amps Iâve encountered⌠Proper old school training somewhere in the military. That said I still think this wouldâve been a Saturday morning job or âhomerâ. It wouldnât have been supplied through a dealer like that.
Are you suggesting that PQ didnât pay very well so the guys did work on the side 
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This arrived earlier;
Its a Copland CTA407 and itâs a replacement for the CTA405 which I loved (and, slightly confusingly, the CTA408 which sounded great but was aesthetically challenging). Youâll note itâs on the top of the rack. This is because itâs too porky to go on the amp shelf;
Bulk notwithstanding, it sounds very similar to the original CTA405 (as distinct from the later 405A), in part because it has returned to using 6550s instead of KT120s which means Iâm happy to forgive it being a bit of a fatty. Itâs yours for a thoroughly reasonable ÂŁ6,500.
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Still with silly reverse volume control?
Anyway, in other news and while it may not be many peopleâs idea of fun I sort of couldnât resist this given a 15% off on ebay code.
I particularly liked the silly volume control. Calibrated in 6dB steps, lovely!
Sort of. You rotate it the conventional clockwise way to increase volume but itâs reverse calibrated, as @amdismal notes, but not in fixed steps;
Seems perfectly reasonable to me - itâs an attenuator, so reducing dB attenuation as you turn it up makes perfect sense. 
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Sorts out the engineers from the unworthy.
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Yeah the engineers clearly have the marketing bods by the gonads there 
I liked my dads old Sansui amp for this exact reason, had wonderful knob feel tooâŚ.
Have you lost your bearings Sir? Itâs Tuesday.
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Itâs probably the bearings which are responsible for the wonderful knob feel.
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