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

Here is a review that answers your questions. 
 

No speaker of the 702 Signature’s size is truly a full-range speaker. It’s not physically possible. Only adding a quality, well-calibrated subwoofer or two can achieve the lowest frequencies from movies and music. But for those who can only use a stereo pair of loudspeakers due to limited space or other reasons, the 702 Signature delivers more emotion and bass impact from movies than most speakers its size. I heard decent bass energy from the 702 Signatures down into the mid-thirty hertz range, so they should be able to deliver the lowest notes of ninety-eight percent of music accurately. Unless you’re heavily into pipe organ or dubstep, these speakers are more than capable.

 I learned than an amp wattage is not just how loud it can get, but that it affects the quality of the sound even at lower volumes when output wattage is waaaay below the max.

The measurement guys don't believe this but it's true.

You guys are right and my conclusion was oversimplified and impossible to generalize. So let me try again:

Moral of the story: never dismiss a pair of speakers before feeding them at least half of their rated maximum wattage!

Also: "Details matter" - @jjss49 (and thanks for explaining why!)

I still don't understand why B&W would risk making customers (and reviewers) unhappy by rating these speakers at 8Ω / 30-300W. But what do I know...?

A few more thoughts about the MA352:
- The headphone amp is noticeably better than MA252's.  I looked into it and the MA352 has something called "Headphone Crossfeed Director (HXD®)" that the MA252 apparently doesn't.  What a nice, unexpected surprise!
- I dig the default EQ both at low and high volumes.  No urgent need to play with the 5-band EQ but it's nice to have it.
- I am happy to find that even low kbps tracks sound better.
- I know its looks are controversial, but I think it's one of the best-looking amps out there.  Yes, I even dig the fake green tube LEDs. I just wish it had the blue OLED display of the MA252 instead of the very 90s-y green one (why doesn't it??).
- I know there are better amps/speakers out there, but I'm so happy with this pair as a starting place to build upon. Maybe a DAC upgrade is next?
- I am curious to hear how much of a difference the REL S5/SHO will make in my setup, because honestly, I listen to it right now and I ask myself how much better can it get?? 

Daniel

@dridel 

I still don't understand why B&W would risk making customers (and reviewers) unhappy by rating these speakers at 8Ω / 30-300W. But what do I know...?

Because B&W cannot account for absolute pairings, given the diversity of the amplifier universe, vintage through cutting edge Class D, nor usage situations, nor user preferences.

The question to ask yourself is: are you really in a position to come to a conclusion and a "morals of a story" statement after trying a single amp that works for you?

Just to be clear, the above is meant to be helpful [read not critical]. 

Again, I'm glad and happy you've found a solution that works for you. At the end of the day, that's all that matters.

 

B& W is now owned a firm that knows nothing about audio or cares to .

Fews years will be another , true of all almost old name stuff .