Audio Research Corp Ref 5 SE

I'm breaking in my upgraded phono 2SE. Right out of the box it sounded wonderfull for some hours: transparent, detailed with slam and a very present bass. Then the sound collapsed. After 600 hours the heights and mids are wonderfull, but I'm still missing the bass: ok it's detailed but it seems to stay behind some db's.

Brill, stay with it. My Ref 5 SE sounds great! I've got about 700 hours on it.

@Bifwynne. Is the bass the last to snap into place?

I don't recall. At this point, I think the whole presentation is quite impressive. Just curious, what's the input impedance of your amp? Is your Ref 5 SE driving anything else like a sub woofer? As an fyi, most ARC line stages, incl the Ref 5, should not be driving a combined load of less than 20K ohms.

Two comments -

First, I have around 150 hours on my Ref 250 amps and my Ref Phono 2SE and what I have noticed is an not so subtle improvement in transparency and sweetness in the highs. The bass out of the box was really great. Right now, it may have toned down a bit in the bass, but having never been a believer in component 'break-in', I am really starting to become a believer now.

Second, Bifwynne, I am contemplating replacing my Rowland Synergy Iii with a Ref 5SE to have an all ARC system. I also use a REL Gilbraltar sub with only a load of 10K ohms. I don't like hooking the sub up to the amps, so I run it through the preamp main out. Based on what you described in your previous post, would that be a problem for the Ref 5SE?