Musical Fidelity A3cr Power Amp ?Break-in Period?

The A3cr does not have the sheer grunt of the 8008BB so a direct comparison would definately show a lack of bass. If your speakers are biampable I would definately recommend adding a second A3cr.

Platsolos,
I own the MF A3CR amp and pre-amp combo. Lots of play is in order to "break-in" the amp. Though longer is better, you'll definetly hear maturity within a month. I started driving Thiel 1.5's with AP silver oval and if that smoothed out, so will your sound. As I upgraded from a Marantz CC65SE CD player to a Sony SCD333SE to a Cary 306 and to the Cary 306/200 now, the A3CR accommodated. I think your CD is probably contributing to the grain?

My speakers are now Merlin VSM-M and all cables are Cardas Golden Cross. The Golden Cross cable will tone down the brightness and grain. Experiment with cables if still not pleased after a month. I realized an incredible improvement with a topline PC too!

The Thiels are rated to go down to 42 and always sounded good to adequate in the low end with A3CR power. Merlin's with BAM go to low/mid 30's. I get some staggeringly low and accurate bass notes into my 10 x 12 listening area now from the Merlin A3CR combo!

This amp is surely not a thunder god, but does almost everything well to excellent considering cost! Though I'm ready to upgrade both MF components to better match the Merlin's incredible abilities, my sound is very smooth and musically satisfying. This amp deserves it's Stereophile class "A" rating.

Hope it works out for you.

What is the best way to break it in? Do the speakers need to be connected to break it in? I can run my tuner to the thing all day if I need to, but if the speakers have to be connected, I will have to keep the volume down.

Platsolos,
Being as you're not trying to break-in the speakers, you don't need to have it loud. I'd keep the speakers connected and maintain a signal flow from any source i.e. CD, tuner, etc. Your objective is to just keep the amp warm and juice running through it. Personally, I'd use the repeat on CD with the Cardas burn-in disc. This disc has various noise tracks to assist burn-in and full frequency spectrum tracks that supposedly de-mag the system. I beleive it works and was recommended in the TAS mag. a few back. There's some cross polarity thing you can do with the speaker wires, but I'm not sure exactly how that works. I think that's a trick to assist speaker break-in as it draws more juice, but lessens the volume? Good luck.

I've had the A3cr since last Oct. I think it started to break in at 40 hours and toook about 100.
I still think when it has been off for 3-4 days it needs a couple of hours to loosen up. This is the feeling I've had with it in the past few weeks. I wonder if long term ownership will prove this weakness I percieve to be a reality.
Grainy? No way. Not in my opinion. Maybe your CDP or DAC or dirty wire connections. M-F is smoooooooth. Maybe too smooth.