The notion of "house sound", to me, goes out the window when: one factors in overhauling 45 year-old componentry with new/better parts of stricter tolerances
far above what would have been sourced for something mass-produced on a specified budget (the reason a conglomerate -like Superscope- felt the bottom line need to export manufacture of a once "boutique" electronics firm to an Asian supplier to begin with...Saul, Sid Smith, Dick Sequerra, Bongiorno didn't stay on to work for "Standard Radio": Standard Radio couldn't have afforded their designs).
Whether a 2230, 2275, 1060, or 4240 (out of all Superscope-era "Marantz" I've used, I liked the 1060 integrated the most and had it set up the longest: 5 years); replacing just the preamp resistors, for example, with 1% metal films
will turn it into something in an entirely different league than it ever could've been even new (let-alone: ditching the electrolytic crossovers and substituting metal polypropylenes).
The achillies heel one learns of in many a receiver/amp, unfortunately, and realizes one is stuck with is:
the power supply and voltage rails. If they're claiming to have sufficient-enough wattage -one would think?- to be able to drive, say, a formidable acoustic suspension speaker of similar vintage...yet start showing obvious signs of trouble (ex: dial lights dimming on musical peaks, clipping, high order harmonic distortion, fuse blowing or outright fire) then: SOMETHING is definitely skinflint "under the hood".
By the time I'd found -and rebuilt- a Quadradial 4240, I'd also found a pair of the legendary A.R. 3a speakers (I'd been using A.R. 2ax's before -successfully- with the 1060 as well as with the 4240, in 40w x 2 mode)...but, short of (still) longing-for a pair of either A.R. 11's or LST's, the 3a's
were of undeniable -and historical- stature above and beyond the 2ax's and begged to be used in all their restored glory. Much to my disappointment, though:
the 4240 couldn't even cough-up full power to run them MODERATELY...it was restricted to 17 x 4 mode to save itself from spontaneously combusting (which, of course, can't handle any speaker -seriously?- other than those intended for 10-watt tube amps...forcing one, then, to pair a BPC EQ with them sporting the notorious "smiley face" to even pretend to offer a semblance of full-bodied sound).
Later in 2011: I got -and rebuilt- a Sansui 4000 and gave away the 4240 to a friend who'd gotten displaced by Hurricane Irene. [The flaw, by the way, in Sansui's "house sound" is: the Hitachi 2sc458 rotting AF transistors their preamp sections are loaded with...get them outta there and, again, the component becomes better than it ever was at the factory]. The Sansui, however
(with a physically smaller-looking power transformer than the Marantz 4240 and only 12,000 combined uF of power filtering vs the 4240's 20,000), was able to run a pair of 81db-(in)efficient A.R. 3a's at a suitable enough level without fear of imploding (then, I realized: the fact that Sansui had started out as a power transformer building specialist -while the Tushinsky brothers were hocking "widescreen 3D" prior to getting into audio on the backs of distributing SONY-
probably had a little to do with this revelatory paradigm).
I've since moved onto TANDBERG (which has two bridge rectifiers and a preamp section double the layout size of what one would find in a typical, '70s receiver outsourced to Japan) and: it can make 4-ohm speakers shake the house all day long with
only 45 watts per channel.