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

 

Vandersteen 2CE Signature III:

Recommended Amplification

40-160 Watts Into 8 Ohms

Frequency Response

29Hz – 29kHz +/- 3dB

32Hz - 21kHz +/-1.5dB

Sensitivity

86 dB, 1 meter with 2.83 volt input

Impedance

7 ohms nominal 4 ohms minimum

 

B&W 702 S2:

Power Range 30-300 
Frequency Response 46-28k Hz 
Sensitivity 90 dB 
Impedance (Ohms)

 

As I pointed out earlier the 46 Hz versus 29 Hz is reflected in the low freq trailing off in the link. So one would expect the 2C versions to play with more authority at the lower frequencies.

However the 86 versus 90 dB sensitivity, would favour the 702S2.

The “fact” that that same amplifier works nicely on the 2C can make us wonder if it is all in the more extended low frequency? Or if there is some load complexity that is also at play?

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

My first post. I pretty much had the same problem you have. A few months back I decided surround sound isn’t making it with me with stereo recordings. So pulled out my vintage 1985 Kenwood Basic M1 power amp and Kenwood Bacis C1 Preamp. I also kept my Klipsch KG4’s. Due to some of my hearing loss I use a Yamaha equalizer to suit my lost frequency in hearing. The KG4’s have good highs and pretty good lows. But missing a lot of mid range. My fix was to add another  M1 power amp and bi-amp to a pair of Klipsch RB3 bookshelf speakers. For me it made the the mid range much better. I also added two 12” subs to finish off the bass I also needed. For now I am done.

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.