What should I upgrade -- speakers or amp?


I'm a relative audio novice who's been slowly building a system over the last few years. I'm considering what to upgrade next. This is what I now have:

B & W CDM 7 NT speakers (2)
Magnum Dynalab MD 208 receiver, 150w
Consonance Droplet CD player (tubed, upsampling)
Sony SCD-595 SACD/CD changer
Kimber Kable Timbre Interconnects
audio store speaker cable

(Two digital sources because I use the Sony for more casual listening, & the Droplet for more attentive sessions. The Droplet was supposed to replace the Sony in my system, but because of the convenience of the changer, the Sony never went away.)

I listen mostly to orchestral/opera, with some chamber music & jazz thrown in. I also listen to FM radio a lot, and live in an area with poor reception. But the Magnum Dynalab has superior reception, even without an ouside antenna. So I'm happy on the tuner front.

I'm considering upgrading either the speakers or the amp.

At the moment, if I go with speakers, I'm leaning towards pre-owned B&W 804 or 803. I'm impressed that most classical studio recordings are made with B&W monitors. And the B&Ws pass the wife acceptance test (the system resides in the living room). I've been happy with the CDM 7 NTs. But I'm open to other speaker suggestions.

Another possibility is to get a new integrated amp. (I have space issues, and also would rather not get into all separate components to avoid unnecessary complexity. I enjoy the equipment, but fundamentally I'm a music-lover, not a gear guy.) In stores, I've liked the sound of the Krell KAV 400xi. If I got one of these, I'd probably use the MD 208 as a tuner only.

But the purpose of this post is to get your suggestions. Which would likely give me the most improvement in my listening experience? Are there other components I should consider?

Thanks in advance for your thoughts, 'goners.

ggl
There's a pair of B&W Silver Signature's listed on Audiogon right now: http://cls.audiogon.com/cgi-bin/cls.pl?spkrfull&1175482531

These are supposed to be one of the two best speakers from B&W, the Nautilus (big seashells) being the other. I sold my pair of Silver Sig's last year after having them for nine years. They weren't even lacking in the bass enough to have made me want a sub.

I honestly sold them because, like a car, I just wanted something newer. I auditioned speakers for three years, trying to find something better. I even auditioned the 803D's three times trying to find them better than the Silver Sig's, but to me they weren't.

The three I found were the Magnepan 3.6R's, Thiel 2.4's and Harmonic Precision Caravelle's. I bought the Caravelle's because my listening room is only 10x12.

Check out the Silver Signature's pictures too, if you want to talk about a beautiful as well as being a fantastic, natural sounding speaker.
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Thank you all for your helpful suggestions; I will definitely look to speakers rather than an amp as the next upgrade.

Jdodmead, I'm particularly intrigued by your suggestion of the Von Schweikert VR4jr's, especially since you had the CDM7NT's, as I do now. Did you consider the 804s or 803s?

How do the VR4jrs compare generally with the 803/804?
I do not care very much for the N803 or N804, in that series I really like the N802. But I like the N803D and I think they are very close to the N802, with a smaller footprint. The new diamond tweeter really makes a difference, plus I think they added another woofer. But they are a lot more money than the Von Schweikerts. The VR4jr's have a very full sound fron top to bottom and are reasonably priced, especially used. The packaging cannot be beat, they come in custom wood crates and I don't think they could be damaged in shipment, unless the truck drove over them. I had it easy though, the internet distributor is only 25 miles away from me and he allowed me to take them home and try them in my own set-up. The Beethovens went on the block the same day, with my wife's blessing. That's not normal, since I didn't own them for very long.
Do a search and you will see that there are a lot of happy Von Schweikert owners out there..
There are many places to listen to B&W, but I don't know about Von Schweikerts and buying speakers without a listen may be a mistake. I would recomend trying to audition anything you are considering, before plunking down the cash. Other components are much easier to recycle than speakers.