I'll be adding 2 Rel T7X subs and getting a new/used SS integrated or amp/pre combo
The sub AND pre outs are a must for me.
The RCA sub output is not needed with REL subs. REL recommends connecting their subs using the high level Neutrik Speakon connection directly to the amp's speaker terminals.
REL T7x manual:
"It is helpful to know that you will almost always connect the REL to the input on the rear panel labeled
“HIGH-LEVEL INPUT.” This connection is made using the supplied 33’ 6” (10 meters) cable, the bare leads
of which connect to the speaker output terminals of the power amplifier. The easy and foolproof connection
at the REL is done with a Neutrik® Speakon® connector. The purpose of connecting to the speaker output
terminals is one of the unique secrets of REL’s success. By connecting to the High Level input on the REL
from the amplifier, you build forward the sonic signature of your main system, including the tonal balance
and timing cues of the entire electronics chain. In this way, the REL is fed the exact signal that is fed to the
main speakers."
Stereo Set-Up of REL Serie T/x
"Stereo Sub-Bass is advised for the fastest, clearest, deep bass—not for more output. Conventional wisdom
has it that stereo subs results in between +3 and +6 db additional output depending upon positioning. In
and of itself, this is of only passing interest in most instances since even a single Serie T/x is capable of
profound output. What then, is the point to adding a second stereo sub bass Serie T/x?
In a word, clarity. Clarity that permits “seeing” back into the farthest reaches of the sound stage. Clarity that
illuminates all dimensions of the musicians and the space that they inhabit equally and enhances the natural
reality of a great full range system, as only RELs can. Stereo Serie T/x produce clarity, transparency, speed
and low level detail NOT just in the bass but throughout the entire spectrum of music."
If you decide to use the HINT 6 RCA stereo sub outputs note that the HINT 6 High Pass crossover is disabled.
HINT 6 manual:
Using Stereo Subwoofers
"If you have two subwoofers and want them to operate in stereo you can connect them to
the Left and Right Preamp Output jacks instead of to the Sub Output jacks which are
mono. In this case you would need to set the High Pass crossover switch to Off. With
this configuration the front panel Sub Level control does not function."