Next step suggestions, from Spendor SP100r ?

I've own S100s (twice) and currently own a pair of 9/1s.

Bass extension can be addressed by adding a subwoofer. I prefer REL, but there are others. Better control and possibly punch can be addressed by products like the DSPeaker Anti-Mode 2 equalizer. I haven't tried it, but it's received great reviews in TAS and Stereophile. Both have noted that it is easy to use and reasonably priced.

The upper bass of SP100 can overwhelm certain rooms (not necessarily small rooms) and make the speaker seem a bit muddy. Room treatment, particularly bass traps in the corners of the room can do a lot to tighten up the upper bass and improve the perception of more deep bass impact. The other suggestions about digital room correction and possible use of a subwoofer are also very good.

If you like the basic sound of the SP100, you should look first at such corrective measures rather than looking for new speakers.

However, if you are getting an itch to try something completely new, that can open up a whole new range of possibilities and discovery. It is almost impossible to make specific recommendations, given how even small changes can be significant. For example, the same drivers of the SP100 are used in the discontinued 9/1. The 9/1 is a VERY different sounding speaker -- tighter, leaner and clearer (more "modern" sound)-- which is a plus or a minus depending on one's taste. That is why I cannot begin to guess what would be a suitable recommendation for something "similar" but perhaps an improvement.

At best, I recommend that you look at speakers from certain manufacturers whose speakers I generally like that I am crudely guessing will be compatible with the taste of someone favoring Spendors: ProAc, Harbeth, Classic Audio, and Sonus Faber.

First of all, thanks to everybody :-)
Yes, I'm starting to imagine which loudspeaker could be the next, something to hear that can be considered an improvement over the SP100r. Room treatment can be a problem due to the WAF, there is a good audio technician who is living not so far from me: maybe a good investment can be ask him to measure the room.
Anyway, thanks Larry for your suggestion. My budget should be not more than 12000 USD.
Consider this as a brainstorming and I appreciate every intervention because I need to restrict the models range.
Thanks again :-)

Maz,

To get a better understanding of what you might like, perhaps you can list some speakers you heard that sounded good to you (regardless of price). Also, if you have any other particular requirements or limitations (such as placement issues) tht would be helpful to know as well.

Near or below your price point, I would recommend auditioning the Gradient Revolution (extremely versatile in terms of room placement because the bass section is configurable to match different locations). I have heard this speaker in a small room and in a room where it was placed near the corner and the sound in both instances was quite good.

For a somewhat warm balance (without being muddy or slow sounding) I like the Gershman GAP 828. This might be a little above your stated price range, but, I bet you could work something out.

I personally tend to like speakers that are a bit more immediate sounding (good dynamics, particularly at lower volume levels, sense of speed rather than a slower, "heavy" sound). This sound quality is hard to achieve without becoming harsh or dry and thin sounding. A few speaker companies that manage to pull this difficult trick off include Classic Audio and Horning. I have only heard the higher priced Horning model, so I have no experience with the model in your price range (Aristoteles), but the brand is on the right track to me.

Because you mentioned WAF, I would suspect that Magneplanar speakers might be out of contention. If that is not the case, the 3.7 model is something that should be auditioned -- great value for the money, in my opinion.

Good luck on your search.

I would recommend B&W or high end JBL, but those are probably too forward sounding for you.

I would go with ATC or PMC. They have soft dome tweeters.