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

Does that MS252 have a variety of transformer tap impedance posts?
And was it using the 8 ohm tap?

      Just to be clear, The McIntosh MA252 amp is solid state with a tube preamp.

Your speakers may still need some more time to break in and the woofers to open up, but in my opinion, it’s the MA252. I’m a McIntosh fan, but I am not a fan of the MA252 or MA352 tube integrated amps. They are direct coupled amps and do not use the McIntosh autoformers. I say this as a previous MA352 owner: the bass is sloppy, the mids shouty, the highs brash. I honestly don’t think you’d get the sound you want moving from the 252 to the 352. If you want to stick with McIntosh and an integrated amp (vs separates) consider a Mac SS integrated that uses autoformers. It’s a noticeable difference.

 

EDIT: Just saw your update re: the 352.  Glad you're happy with it.  I would still suggest, if you have the option and a willing dealer, borrow one of their SS Mac amps with autoformers to try and see if you hear a difference.  Use your MA352 as the pre so you're keeping everything else the same and just comparing the sound of the 352's direct coupled amp with an autoformer amp.

So I am powering the B&W 702 Signatures with a 20 year old McIntosh MC 202 (200 watt) solid state amp with a MC C41 solid state pre-amp and the B&W's just come alive every time I power them up.  The sound stage and clarity are stunning when fed a good recording. I'm glad you resolved your issues.  IMHO, McIntosh power is well suited to running the B&W 702 Signatures. 

After a long weekend enjoying my dealer's MA 352, I went to return it today.  I also asked them to check my MA252 for problems, since many people here felt it should be able to drive the 702s. They confirmed the issue is just that the 702s need more power.  I wanted to audition the Michi X3, but they didn't have one in stock and they were very confident the MA352 is the superior amp.  So, I pulled the trigger and took the MA352 home.  I also bought a Panamax MR4300 even though I'm not 100% sure how much effect the power conditioner had on my setup.

The MA352 + 702 Signatures combo gets me very close to the best setups I have heard at dealers for much less money and before even playing with speaker positioning and room treatment. Let alone upgrading my DAC, cables, etc. I know I shouldn't say this, but I really think this is it for me.

Moral of the story: make sure your amp has AT LEAST HALF of your speaker's maximum rated wattage!

Hmm... I must be highly immoral. The 3 watts of my amps are (at max power) 7.5% of maximum recommended power (40 watts), for my speakers. Or 15% of half power (20 watts).

Moral of the story: make sure your amp has AT LEAST HALF of your speaker’s maximum rated wattage!

 

Your story. Your morals. : )

Happy you’ve found a pairing to your liking and are enjoying it!!!