Underpowered?


Hi guys.  Newbie here asking for advice. 

I recently purchased a pair of B&W 702 Signature (8Ω, 30-300W, 90 dB) to replace my old faithful 683s (8Ω, 20-200W, 90 dB).  I am running them with a McIntosh MA252 (100W into 8Ω, 160W into 4Ω).  I purchased them thinking they would complete my end-game system.  However, my excitement turned into disappointment when I realized the lows were somewhat lacking.  For all their faults, the 683s had a great dynamic low kick (no sub) that I was looking to take one step further.  Unsurprisingly, the highs and mids on the 702s were indeed more detailed and separation was clearer, but I couldn't get over the uninspiring lows.  I found myself listening at higher volumes chasing for that bass oomph.  Neither playing with the EQ at the source nor the amp was satisfactory.  So, I did the research that perhaps I should've done before purchasing the 702s and found out they are quite power hungry despite the specs being similar to the 683s.  I emailed B&W and McIntosh and they agreed the amp is probably underpowered for the 702s.  B&W described the sound of an underpowered speaker as one lacking low response and details, which is spot on. McIntosh suggested the MA352 (200W into 8Ω, 320W into 4Ω).

Of note, I love the MA252 and really wish there was a way to make this work.  I don't need a DAC/streamer/etc so I'm happy to put all my money on better sound vs tech features.  But I also think the speakers sound amazing even when somewhat underpowered and I'm considering upgrading to a MA352, Michi X3, Hegel 390.  Another option could be to get a sub? But I feel that would defeat the purpose of having a 3way standing speaker and then I might as well get a pair of bookshelf speakers (805 D4s, LS50 metas?).

So what do you guys think? Is it normal for a speaker that's rated 30-300W to be underpowered with a 100W amp?? What would you do:

  1. Sell the 702s and look for a better match for my MA252?

  2. Upgrade the MA252 (MA352? Michi X3? NAD 33?)?

  3. Get a subwoofer?

I would really appreciate your thoughts/advice!

dridel

I just looked at the specs.  There's a combination of fast roll off below 100 Hz (pretty high for a floor stander!) and an impedance dip there at the low end.

I'd strongly suggest you measure your room before making any adjustments, but I would not be surprised if you are a very good candidate for a sub. 

You'll want something with some built in DSP capabilities to help you manage room modes, and, as always, consider room treatment before you do anything else.

Actually I just thought of a combination for you to try. Plug the ports and move the speakers closer to the wall. Plugging the port will damp the peak at 100 Hz but more importantly slow down how fast it rolls off below that.

If they still sound anemic, you definitely need a higher current amp (not necessarily more watts, more watts in the bass).

If they suddenly improve, but you still want more bass a sub is a good option.

I have some friends who use the new Vandersteen Sub 3 over their previous REL in that situation since they design them to keep the sound of the main amps so you can tell where they cross over , plus that takes the load under 120hz away from the main amp and speakers.  Speakers and a,ps get the advantage here. They are also fully adjustable for the room with a built in 11 band EQ. Just a thought. Designs change and maybe the newer speakers just don’t kick like the older ones. No idea there. Good luck 

op - a few thoughts

1. speaker placement and room loading is key to getting good bass response, try that in all reasonable permutations before changing equipment

2. treble and midrange clarity will always seem enhanced when there is less bass foundation (or bass boom)... those things are highly interrelated... trick is to have cake and eat it too

3. subs can certainly help (a pair ideally), rel’s are very good, others are good too - but note point #5 below

4. the mac 252 should have ample power and grip to drive the b&w’s -- you can try a different amp (a hegel is what i would try if you go that route after doing point #1), but i suspect things won’t change too much

5. there is a recent thread on big vs small (satellite type) speakers... that may be a good read for you... bottom line is big speakers sound bigger, it is not just the deep bass, it is how air is moved, and midrange and midbass is presented in a much more easeful, enveloping, full, rich way... that is the difference

good luck

  1. Sell the 702s and look for a better match for my MA252?

Dang, you got yourself in a tricky situation. There is no easy way out. I'm not a big McIntosh fan but the MA252 is a neat unit and 100wpc is enough if you are not trying to wake the neighbors. Perhaps some Triangle Delta loudspeakers (or other easy to drive loudspeaker). not a huge step up in efficiency but they will sound good at lower volumes, but you still might need a sub.