Rega Brio Sufficient?

I would think if the spks. you are planning on buying is above 86/87 db per 1w you should be fine. You'll find out soon enough. If the 30w isn't enough buy the Brio 3 and keep both. My Brio 3 is having no problem at all driving my KRIX Apex III MK2 spks. which are about 88db effecient (8 ohm). (BTW, I think the 49w per/ch. rating is very conservative on the Brio 3.)

Start with your old Brio and see how it works out. If you find the sound muddying up on crescendos or it dulls down transients to make the music sound overall flatter, a power and current delivery upgrade is in order.

Before you automatically upgrade to the new Brio, listen to some other integrated amps in its price/performance niche, such as the Cambridge 640A v2, Music Hall 25.2, and especially, the Onkyo A-9555.

I say all this about the Onkyo from the perspective of using some respected high current power amps for the last dozen years. I have also helped friends and neighbors install affordable 2-channel systems using integrated amps from Cambridge and Creek. I used to power my 2-channel system with a Musical Fidelity integrated. Recently I heard the new Rega Brio powering Rega floorstanding speakers.

For transparency, speed, bandwidth, musicality, clarity, dynamic range at both ends of the loudness spectrum, and musical involvement, this Onkyo integrated smokes them all.

It should match well with your new RS6's and bring them alive. My Onkyo drives a pair of Mirage OMD-15s, which--like the RS6's--are rated at 91 dB efficiency, and have multiple mid/woofers in a ported enclosure. Although my VSP Labs TransMos 150 power amp weighs 50 lbs and is rated at 150/300 wpc into 8/4 ohms, the Onkyo integrated sounds bigger, clearer, more extended in the bass, and in general, more powerful.

At $450 from J&R or $474 from Amazon, it's pretty hard to beat. It DOES require a good 100 hr break-in before it shows what it's really about.

Hold on to your Brio. I have one in an office system, and it's a satisfyingly musical little amp. I'm driving very inefficient speakers with it (Spendor S3/5) -- not very loud, since it's the office, but when I have turned it up, it still sounds great. The Brio is an excellent performer. It's not the last word in transparency or accuracy but when it's playing it's easy to just listen to the music without thinking about how it sounds. Another amp might give you more power but less musical pleasure.

Also, Sterophile's review of the Monitor RS6 says they're pretty efficient and easy to drive -- so, all the more reason to give your Brio a chance. (From the review: "The Monitor Audio Silver RS6's estimated voltage sensitivity was 89.5dB(B)/2.83V/m, which, if slightly below the specified 91dB, is still higher than average. Its impedance (fig.1) remains above 6 ohms for almost the entire audioband, with a minimum value of 4.5 ohms at 165Hz. As well as being usefully sensitive, the RS6 is also an easy load for the amplifier to drive.")