Rogue M-150 upgrade to M-180 Questions


So, if you have either done this upgrade, or heard a set before and after, what did you notice? I am wondering if the upgrade is a good allotment of funds (plan B would be upgrading my digital source, currently a Modwright Platinum 9100 Sony) Speakers are Tyler Acoustics Decade D1's, relatively easy to drive.

Things I like about the M150's (tubes are Svetlana 6550's, RCA Clear Tops, and Telefunkens) are holographic imaging, huge soundstage, deep bass. Things that could be improved on: clarity, tighter bass, as it can be a little boomy at times, transformer hum is noticeable.

Do you think the upgrade would make the amp improve in those areas? The increase in overall power would be nice, but I am running it in triode, as my speakers don't require a ton of juice, and UL mode just flattens out the imaging a bit, with no offsetting benefit.

On a side note, has anyone heard the upper-end Rogue preamps? I see one for sale on here right now.
dawgcatching
I have compared [at a friends house] 150s vrs 180s side by side, and even swapping tubes from one amp to another to keep variables the same. the 150s are warmer and rounder in and old school tubey way, the 180s have more extension from top to bottom with a wider deeper soundstage, and with string instruments it was like taking a blanket off the speakers, way more lifelike attack and sparkle, making the 150s sound rolled off and dull by comparison. this was with revel gems for speakers and bel canto dac 3 front end. I would say for most people the 180s are a great upgrade.
How much is this upgrade worth?I got the 150's at home and being happy overall with them so far.