No bass in the Proac Response 3


I've just had the opportunity to buy a Proac Response 3 from a fellow agon just recently. One of the foam the 6.5" woofer was
torn ( with holes) so I already had it replaced with brand new foam. The treble improved quite a bit once I had the foam replace. The midrand is still the same and I have to say the Proac midrange is beautifull. I can sit and listen to female vocal (Krall, Elle, Cassandra) music all day. There is no sign of harsh or etch at all.

However, my problem now is that the bass is nowhere to be found when I play rock/pop. I do the regular Proac reccommended speaker placement of 2 feet away from the wall and the deep bass , mid bass are all but lost. If I moved the Proac very close to the wall then I get stronger bass, but now my image and everything else got all messed up. A simple analogy would be like I don't feel the singer is standing in the rooming sing anymore once I move the speakers toward the wall. Everything is just so flat ( 2-d), but the bass is good.

The most simple weak link that I can see in my system is that maybe the Krell integrated is just not big enough to produce the kinda big bass that I used to. But another interesting thing to know is that before I got the R3, I also got a much smaller Proac supertower that produced bass twice as much as the R3; and the R3 is twice the size, but lacking in the lower freq department.

My system is following:
Krell KAV-300i (integrated amp)
Arcam DV-27 (CD player)
Sony DVD player + PS Audio UltraLink DAC
Proac R3 (Full range speaker)
ducchau
If ALL the 6.5" drivers had their foam suspensions changed out then you will need break in time to get the bass back. If only one driver was changed and suddenly bass has disappeared, the last post may have merit... did you somehow reverse polarity when re-installing said woofer back into cabnet?
Otherwise break-in time should bring it back.
I don't know about Krell's integrated, but the old Krells had great bass. About class A: Some Class A's are better than Class AB but Class AB done right (like an Eagle 4) are no issue. My old Forte 1a (50 watts class A) was pretty good in the bass, outperforming some 250 watt amps I compared it too.
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If you are filling the cabinet with sand you are changing the internal volume of the enclosure which will change the frequency response of the speaker, most notably reducing the bass response. Try taking the sand out. You could try a shopvac with a small hose through the port. You may need someone to tip the speaker while you vaccume. You have plenty of power for the speakers. I've heard them sing with 25w Quick Silver Mini Mites. I agree with Dodgealum, the response 3's never had a lot of strong bass and are a little lightweight in presentation, especially for thier size, but are a very nice speaker. New surrounds, as others have said, will take some time to break in, sometimes hundreds of hours. Upgrading the crossover with capacitors of your choice will make a wonderful improvement.
Aside from all the great comments already posted, have you fed the speakers with test tones? Also, since these speakers are bi-wires, have you tried to use the 'low' set to see if any difference occurs? With different aged drivers you are always going to have differences in the response. In speaker land, there is something called 'matched drivers' and that can have some impact on what your listening to now. I had that problem many years ago when I replaced a woofer in another ProAc model.
Hifibri, how could the sand filling change the internal volume of the cabinet when the cavity that contains the sand is totally separate from the other box that contains the drivers ? So this is the point that I don't quite get from all the techniques of higher end speakers designers use.

However, I did remove half the sand last night and it seems to help the bass quite a bit. Although not to the point that I am happy. So more speaker placement experiments.

Jea, thanks for the technical trick to test out the polarities of the speaker connections. Although I feel that I did connect the speaker wires correctly, I will try what you suggested.