from 87db to 90 db ?

is there a way to make your speakers more sensitive ?
im interrested in a pair but they are 87db, i would prefer them if they were 90 - 94 db
Boy would that be sweet.
Try sensitivity training. You're in Sweden, so they must have such things no?
Maybe go with some nice flower arrangements in the listening room? Buy a "Best of Oprah" dvd and put it on continuous repeat? Dress nicer when you listen to them and take them out of the house once in a while?

I.E. - There's not a practical solution that I'm aware of.
Some people go with autoformers. Paul Speltz type (or something like that). They can greatly improve the sensitivity of speakers.
An autoformer makes no difference to the sensitivity of the speaker, but it raises or lowers the input impedance, to better match to the driving amp.

Many low power amps have limited current delivery capability, so they will be able to play subjectively louder with a higher impedance load.

Nevertheless Aballs suggestion may be a good one if you can tell us the type of amp you are using, and the input impedance of your current speakers.
I'm not positive, but I think an active crossover may raise the sensitivity.
If you normally listen 3 meters away from your speakers, then shortening the distance to 2 meters will increase the SPL by 3.5 dB. It's not what you're asking for, but it does the same thing.
I didn't phrase my post correctly. Of course the sensitivity isn't changed if the modification is outside the speaker! Arthur
One thing you might want to try is a little device a friend here on Audiogon and I found a couple of years back while trying to find a sympathetic speaker for his very low power amplifier.

Of course, it will not raise the sensitivity of your speakers, but the AR TDS (forget the model #, but I could look it up if you were interested), truly doubled the volume coming out of the system. We tried it between the source and his amplifier, and it took us from being able to use 2 or 3 speakers with this amp to a whole lot more - maybe 25?

We noticed no sonic disadvantages to using this device, and we tried it in several systems. However, over time, I did find out that in some systems, it can really muck up the sound, taking away from bass and putting other things in - sort of a "robbing Peter to pay Paul" scenario. Still, you might just want to give it a shot, as in most systems, we got the loudness doubling, with no degradation. If they work for you, they definitely open a lot of doors into the type of speaker selection you outlined.
Trelja, is this the device your describing?
The answer to your question is no, unless you want to make major changes to them.

Sensitivity is basically a function of the drivers and the crossover with some contribution from the cabinet. You could increase the sensitivity by making appropriate changes to these, but you would also change how they sound. Unless you really know what you are doing you are going to end up with a mess.

If these are the speakers you want and they are not sensitive enough for what you have then you need more power.
Yes, Albert, that is it!

AR has a lot of information out there all over the place. They make a lot of claims about this or that, yet nothing about the loudness effect. It was funny that I never heard anything that they said it would do, but they never have advertised the one thing I have found it to do. On top of this, as Music Direct writes, it is completely passive.

Again, when it seems to effect the sound in a negative way, it makes it BAD. But, if one is lucky to have appear "transparent", the gain in volume would be a serious boon to a low power devotee.