New or Used Amplifier

For HT.....used.

With your YBA gear, I would suggest that you keep it in the same YBA designed family and go buy their used Audio Refinement Multi amps. (YBA designed but made in China line-up)

They impressed me enough to buy their 3 channel and the separate 2 channel (both used) to incorporate in HT. They serve as the centre channel, reads, and surround amps. Their superior build quality bested the top CAMBRIDGE AVR that I sent lacking. They now mate perfectly with my primary 2 channel for audio integrated amp with its direct pass-through (REGA Osiris ) as the LF and RF when I need it for HT.

Google the AR stable of amps, If memory serves me, they also had a full 5 channel.

Canuckaudiomart has an Audio Refinement Multi 5 and a Multi 2 listed for sale

Your in-wall installation (asssumed so) is going to have to be fire rated speaker cable or your insurance policy exclusion clauses be come an issue.

Because

(I) it is the just the rears and surrounds on the long runs, AND
(II) you are using a hi-quality build amp to drive them,

the BELDEN line (a range of quality and gauges) will serve very nicely IMO. I used them to surprisingly good results on the advice of the Dealer for long in-wall runs.

Alternatively I wired the next room with Van Den Hul.... more expensive but I did not see any improvement over the cheaper Belden .

Center channel .... a different story here: a hi-quality speaker cable required to match you hi-quality LF and RF cables is strongly suggested to aid in getting that seamless soundstage across the fronts. Don't cheap it here.

ICs: I started the HT expansion journey with NORDOST FREYs that I still have for L-F 2 channel. I then went to NORDOST HEIMDALLs for all of the the centre, rears and surrounds.

Good ... you betcha ..... BUT ..... the AVP had the usual cheap stamped nmtal very crowded back panel and comparative cheap usual connectors that made the locking WBT RCAS on the ICs a big hindrance.

I went with ATLAS All-CU Navigators and then to REGA COUPLE ICs. The REGAs are the Goliath killers and for conveying the purely manufactured signal in the rears and surrounds. they are my choice as superior top performance at a good price.

Their performance is way above its weight class and the Neutrik Profi RCA connectors are outstanding and arguably on par (at least) with any of the WBTs for this selected performance criteria ,

The centre channel IC is still NORDOST to match the LF and RF.

Go to TAKEFIVEAUDIO.COM , send them an email and get the Belden vs ?? Speaker cable choices straight goods right from the quality parts dealer that I used.

He will ask you more details about your gear, your room, other factors etc. and he can provide a much better choice(s) option(s).

HIFISHARK.COM .....
They have speaker cables and ICs for sale

Repost

YBA Diamond cables .... Listed on Hifishark.com

I've bought used cables from Europe with no hassles as long as it's on their local used audio sites or a reputable feedback dealer on EBay.
I would not buy squat out of Asia particularly China or Singapore -full stop.

U Pay the shipping, U pay the duty and local taxes if it applies , Unpay the small brokerage fee if there is duty .... using Fedex or like is one stop shopping and easy single pmt on the credit card .... Easy and good to go.

We live in a global arena in this hobby.

The speaker wires length is not going to hinder you
I ran about the same length (up the walls, the length of a long room in the ceiling , down the walls plus the hookup lengths) without any difficulty.
I use the 3 channel amp for the centre channel and the rears, the two channel for the side surrounds.

The separate preamp processor is the " disposable" part, to be upgraded in the future as the codecs change.

Recommended : NuForce AVP-18.... Fully digital with all HDMI (no legacy inputs ). Google the reviews - highly recommended .... Especially with the ARCAM Bluray player to round it out.