Pass X150.5 or Odyssey Stratos monos?


After months of research and mental anguish ;) I've narrowed down my search for new amplification to the two in the title. There are obvious differences like the fact that one is a stereo amp while the other are monoblocks. Anyway, if you had to, which option would you go with and why? Thanks!
whatsmyname

Showing 2 responses by almarg

Hi George,

I think I see what you are referring to in the photos. In the mono version there is a sleeving containing a red wire and a yellow wire, which appear to connect the amp’s output connectors to the printed circuit board. With the red wire going to the part of the circuit board that is associated with one channel in the stereo version, and the yellow wire going to the part of the board that is associated with the other channel in the stereo version.

Which is suggestive of a bridged design. However I suspect that the two channels are paralleled, rather than bridged. With one wire, probably the yellow one, going to circuit ground, and with a connection between the outputs of the two channels being made somewhere where we can’t readily see it, perhaps underneath the board, and in turn connected to the red wire.

As you know, bridging can potentially increase power capability into 8 ohms by 4x (i.e. by 6 db), although most bridged designs fall somewhat short of a 4x increase due to current and/or thermal limitations. But in this case the increase in 8 ohm power capability of the mono version relative to the stereo version is almost negligible (less than 0.8 db). And as you indicated bridging reduces damping factor, while the damping factor of these monos is substantially higher than the damping factor of the stereo version.

Also as you know, paralleling can potentially increase power capability by 2x, while increasing damping factor rather than decreasing it. But IMO it doesn’t speak well of the robustness of the power supply and/or other aspects of this design that the mono version only 20% more powerful into 8 ohms than the stereo version.

In any event, it’s really a moot point as far as we are concerned, as you, I, and several other posters recommend going with the Pass amp whether the Odyssey monos are bridged or paralleled or something else.

Best regards,
-- Al

I believe that the Odyssey Stratos monos are not bridged, and the use of the term "bridged" in their description (" RCA & XLR (bridged) inputs") is misleading.  There are several indications of that:

1) See the posts by me and Stereo5 dated 6-4-2018 in this thread.  Apparently the word "bridged" is confusingly used to refer to a direct connection between one of the two signal pins on the XLR connector and the signal pin on the RCA connector.

2) The specified power capability of the monos is only slightly higher than that of the stereo version (180 watts vs. 150 watts into 8 ohms).

3) The specified damping factor of the monos is higher than that of the stereo version (>800 vs. >500).

That said, and although I have no experience with Odyssey products, as a Pass owner (XA25) I would second the comment by @fsmithjack  above.  The two brands are not in the same league IMO. 

Good luck.  Regards,
-- Al