I intend to buy a receiver soon, but for the ones i'm interested in, there are no reviews to be found.
i'm going to use it only with preamp outputs, so preamp sound quality is primordial for me.

At first i thought about the Integra DHC-40.2 but i think i can get the same quality or maybe better with a receiver, at a lower cost.

I'm interested in those:
Integra DHC-40.2
Denon AVR-3312CI
Marantz SR5005
Harman Kardon AVR3600
Yamaha RX-A700

i repeat, i will not use the built-in power amps, but only the preamp outputs, so what's most important for me is sound quality.

What would you recommend, and why?
cost no object.(does not mean i'm rich).

I would just get the one that has the features you're looking for. For no real reason, I'm not a fan of Yamaha or HK's AVRs, I don't now why, it's just me.

they all have the features i'm looking for:
preamp output on all channels and
various Dolby/DTS decoders.

i'm not very keen on the Yamahas either; the decoder i have now is not very good quality: i took it to a tech. a couple of months ago for a check up. As an example, there is a rotary switch to select different modes (Surround, Hall, Music...etc) and i always had problems with it.
i asked the technician if he could disable this switch and install one just for 2 functions: Surround and Bypass.

he said that the switch has about 40 connections and they're being eaten up by the current passing through, and when it stops working, there's no way he can install another one as replacements cannot be found anymore. He also said that when that will happen, the whole thing will be good for scrap.

I'd look for a deal something non-Japanese, like a demo model Rotel, Arcam, Anthem, etc...even a somewhat out-of-date model will sound far better.

J the H/K 3600 had all of the processing features you were looking for?

Unlike Bruno I am a fan of H/K and I was looking real hard at the 3600 about a year or so ago but it just didn't have the bells and whistles that the other comparatively priced and most typically recommended by the masses AVR's did. The H/K's have always been known to have a conservatively advertised robust power supply but obviously that doesn't play into your scenario. I have an old(ish) AVR635 that I love dearly and has been a champ for me over the years but I really need an upgrade to the newer standard features the more recent AVR's have.

Maybe I'll need to go take another look-see at the 3600.

yeah, what i want first and foremost is preamp sound quality and the latest decoding, like Dolby True HD.

someone told me that, for one thing, preamp outputs in receivers are more noisy than those on prepros.

i think i'll be looking at prepros instead.

right now, i'm having a look at Integra DHC-40.2
and Marantz AV7005

I have the Onkyo 5508 prepro and a 5500 amp, man it's sounds incredible.

Edit: the picture is way better too because I wanted to buy a new TV, but it made the Panasonic 55"Projection HDTV look WAY better.

Hi, I installed a Marantz SR5005 (as a processor) for a friend's dedicated home theatre and it sounds really good; I was impressed.

JB, whoever told you that doesn't have much of a grasp of the audibility of noise and distortion. Pre-amplifiers which typically have a gain of about 12-16dB are quite simple devices as audio equipment goes and any of those in receivers of the quality which we would seriously consider(including all those you listed)have noise and distortion numbers below audibility. If one of them(or a separate pre-amplifier)has a noise level a few dB lower than another this is of no audible significance. Tests of receivers typically demonstrate noise levels(even including the amplification stage)below audibility and therefore operate transparently. Sound quality of basic pre-amplification(i.e., before processing)is a given and can't be used as a determining factor in a purchase decision.

The processing which is designed to change the sound can be a determining factor,of course, and if you're willing to spend the money, in my view you should acquire a receiver with the top Audyssey MultEQ XT32 version. Units presently available with this include the Denon 4311 and Onkyo 3008. Either of these would serve you very well and a choice between them could well depend simply on price.

my mind is made up now; i've come back to my first choices of those 2:
Integra DHC-40.2 or
Marantz AV7005.

the final decision will be made when i'm ready to buy: best cost i can find.

Thanks a lot everyone for your help.
it is much appreciated. :-)