cflammia - Welcome to the forum and to the wonders of high-end audio. I remember the first time I experienced hearing a high resolution system and discovering "new" information in albums I thought I knew intimately.

There are any number of possibilities regarding this excessive sibilance you're hearing. This quality might be endemic to the recording, or might be something in your equipment chain (quite often, but, not necessarily cables.) It could even have something to do with a highly reflective surface in your room -- an untreated wall or TV screen. Perhaps, you could list some of the recordings (along with specific release info to rule out differences in masterings) that you're finding exhibit this problem. This way, if some of the members here have the particular recording, we can crosscheck and let you know if we hear the same thing.

Hi cflammia and welcome to the forum.
I wouldn't call NAD amps and cd players dull sounding but they're not bright either.Not so sure about B&W since it has been a few years since i've listen to one.I tell you what,give your system a few more hours,or rather let your whole system on with a cd on repeat and have a listen again after 48 hours,then post again your findings.Mind you,if you
are used to cheap bookcase systems,the extra "detail" of a good hi-fi might be perceived as sibilance,something most older cds have plenty Another reason for the sibilance might be the interconnects and speaker cables you bought.

Damn it Jeff,where did you come from ? You scared me.I was replying to this post knowing no one answered and when i clicked the "post" button,there you are ! rotfl

I have a second NAD system at home, C541iCDP and C370 amp bridged with C270 amp driving Wharfedale Pacific Evo 40's. No problems. I have had the 320bee also and other NAD amps. I currently drive an Aurum Cantus 782 2005 apeakers which has a ribbon tweeter without the problem.

However, I have found when listening to SOME B&W speakers the problem you mention. Which is one reason I my ears were not attracted to metal dome tweeters. I have found my ears seem for some reason to find metal dome tweeters simbilant and harsh. I much prefer the sound of soft dome tweeters.

Then, again, I ended up with ribbon tweeters that I don't find harsh sounding at all.

So my advice is to try if you are able, a pair of speakers with frabric dome tweeters. It is worth a try, but then again, the speakers may well need more than 70- 80- hours break in, perhaps closer to 200.

I think you are on the right track with your thinking. Many popular recordings are riddled with siblants. However, there are a few things you can try to help make these recordings listenable.

I would experiment with the wood floor and the first reflections from the side walls and try to toe the speakers out as far as I could without losing the center image first.

At some point you are going to have to find a compromise between listenable popular recordings and high resolution for your superior recordings.

I've never heard a Steely Dan recording that was siblant, so if you have any of their music and you get any hint of siblants from the recording then you probably do need to work on ridding it as much as possible. On the other end, mass choral works are often orgies of siblants.

A certain amount of siblants is natural in the human voice, women in particular. After a while you will begin to recognize the natural siblants from the hyped-up siblants of a poor recording. Still, the speaker positioning and room interaction can throw off the frequency response to the point of exacerbating the frequencies where siblants can dominate. Google 'speaker positioning' and try to get the fundamentals as close as your room and furnishings will allow.

I think that in the long term you'll find that the problem is the recordings. Way too many albums mastered in the 80's were done with the bass and high frequencies strongly emphacized. The good old "disco smile" that too many used to set their graphic equalizers with.

For a test, I would suggest that you try listening to Pink Floyd's The Wall, or Wish You Were Here. Both of these recordings have an excellent tonal balance. If you find that you like the way these albmums sound you can be pretty sure the fault is with your recordings and not your system. Then the answer is simple, use the tone controls that NAD so thoughtfully included with your receiver. BTW, NAD uses a very conservative approach with their tone controls so don't be afraid to crank the treble way down. I normally have my treble set to about 3 o'clock on my C372 when listening to some of my overly bright rock CD's and on some I turn it as far as it will go.

cf,

During my long search for a new system I listened to your exact set-up. I found the 604s to be better suited for rock/heavy metal (which I don't listen to)for they seemed to be bass heavy. As for the "s" emphasis, it may be the aluminum dome, as Colin stated.
The NADs sounded much better with a variety of other speakers - I was playing big band, swing, vocals, acoustic and a variety of other music. As one poster said about the "80s" sound...it may be the recording style.
As others advised, give it more break-in time and play with the acoustics before questioning the equipment.
Keep us posted.