Compare: DSP-Z11 (Left) vs MX-A5000(Right)
After going through the catalog as found on the link, I found Yamaha have mentioned their 11 channel MX-A5000 power amp is based on the DSP-Z11 components.
Some noteworthy points:
1) MX-A5000 uses the same cabinet of DSP-Z11 AV amplifier released in 2007.
2) It uses the heatsinks of Z11 which implies power amp circuit design are identical. Minimal cost incurred during designing.
3) The Z11 had 11 powered channels (140 Wpc X 7 + 50 Wpc X 4) @
0.04% THD @ 8 ohms. The MX-A5000 have 11 powered channels (150 Wpc X 7 + 150Wpc X 4) @
0.06 THD @ 8 ohms. An increase in THD level implies under all probability it is (140 Wpc X 7 + 140Wpc X 4) = (140 Wpc X 11) @
0.04% THD @ 8 ohms. In comparison the DSP-Z9 could have pumped out (190 Wpc X 7 + 50 Wpc X 2) @
0.04% THD @ 8 ohms.
4) Z11 used E-I core power transformer while MX-A5000 uses a much higher quality and more powerful toroidal transformer alike Z9.
5) Z11 used a pair of Toshiba 2SA2121/ 2SC5949 power transistors for each of it 11 channels. The rail voltage to the power amp was (64VDC X 2) for its (140 Wpc X 7) channels and (37VDC X 2) for its (50 Wpc X 4) channels. MX-A5000 under all probability uses the same power transistors with uniform rail voltage of (64VDC X 2) for all its (140 Wpc X 11) channels courtesy a more powerful power transformer.
6) DSP-Z11/ MX-A5000 uses 22 power transistors in total for 11 channels. DSP-Z9 used 32 for 9 channels.
7) Since MX-A5000 uses the same power amp circuit board of Z11, it follows Three-stage Darlington circuit topology(mentioned in catalog) for all of its 11 channels. The Z9 in comparison uses Dual Three-stage Darlington circuit topology for its main 7 channels and Three-stage Darlington circuit topology for the other 2 channels. Dual Three-stage Darlington output stage circuit topology is more robust and will be more stable under 4 ohms load.
8) MX-A5000 uses the same 2 X 27,000uF power capacitors of DSP-Z11 for its 11 channels of amplification. In comparison DSP-Z9 uses 2 X 28,000uF for its 9 channels.
I am still to look at CX-A5000 pre amplifier for the details. Any update on the price?