Home Theater Receiver recommendations for B&W 803S?

I thought awilder is now open to spend way more than originally anticipated. 
Yup...I think power cord upgrade is a must for both the Marantz 8802 and the Rotel RMB-1585 amp. Especially the Rotel RMB-1585 is a high current five-channel amp. A stock power cord won't do any good and will limit currents needed for the amp. 
Interconnects and speakers cables need upgrade as well. 

Ok,Ok... NOBODY PANIC! CRISIS AVERTED! :)

@caphill I appreciate your enthusiasm! I do have to keep it under control a bit, and definitely want to maximize value. ;) I'm kicking myself for not buying an Oppo before they closed up shop; the aftermarket prices have gone through the roof! 

So...I factory reset the Marantz, and then did the fully Audyssey setup.  I then listened to a few CDs, and a couple of minutes of the last West World episode.

The good news: The boominess is resolved when Audyssey is enabled. I think it is likely due to my speaker placement; my left channel is just a few inches away from a side wall, and about 2.5' feet in front of the back wall/corner...and that corner of the room happens to really resonate bass (I discovered this when doing my "bass crawl" testing).  The reason I have the speaker so close to the wall is that the B&W's clearly like being spaced far apart...and I've maxxed out how wide I can go in my room.  Thankfully, the Audyssey compensated for it, and the lower mid-ranges now sound much more balanced.

So with this speaker placement, it seems Audyssey is a must. (Not sure why this wasn't an issue when listening with the Denon in stereo direct mode, as the speakers were in the same spots...but whatever.)

I compared Audyssey "Reference" and "Flat" modes quite a bit.. The "Flat" mode (which doesn't roll off the highs) had a bit more crispness at the top end. It was especially noticeable listening to Blue Man's Audio; the striking of the PVC tubes had a bit more of a realistic "pop" to them. But I also found it fatiguingly bright... so I went back to reference mode and I think that's a better overall choice.

I feel like the system's starting to sound pretty bad-ass, but yep, it's not quite there yet. The improvement in detail and instrument separation is significant - I've already heard so much more detail in my music than I've ever noticed before, and I'm enjoying critical listening immensely and discovering much more in the music.

But it's still a bit lacking on the visceral impact and spatial imaging. It didn't make me want to move. I want it to be more engaging. I have a hunch the lack of clear imaging is probably due to speaker placement and room acoustics more than anything else.

So now I need to figure out what to work on next (by "work" I mean "play"... I'm very much enjoying this process and appreciate your both taking me under your wing!).

I know you guys have mentioned the fuses and power cords. I also do need to upgrade my disc spinner, since it's not UHD, and it also doesn't have a digital coax interconnect option.

I should mention that we watch far more theater/TV than I do sit and listen to CDs...and at this point, most of our movie/TV watching is done via streaming. So ultimately this is probably going to be used as a home theater setup much more than straight audio. But if I can get it where I imagine it can get for audio, that may change. ;)

So I'm back to my to do list.  Since I need to do it anyway, I think it makes sense to replace the disc player next, before I tinker with power...but I know you both feel strongly about replacing the power cables and that's definitely still on the list:

- Play with speaker placement (my only option is to move them closer together, or tweak their angles.)
- Replace my Panasonic DMP-DB35 disc player (~$500)
- Switch to 6' coax digital between disc player and preamp
- Silver Fuse for Marantz ($20)
- New power cords ($250+)
- Switch from unbalanced to balanced interconnects between the Marantz and Denon ($150), maybe not necessary.
- Fix room acoustics, if possible ($$?)


Time to take a closer look at the Sony and Yamaha transports you recommended!

Nuprime cdt 8 transport. 

Couple of things I’m going to re-iterate. That digital COAX cable is good for everything except a few scenarios:

- Bluray with Dolby TrueHD
- Bluray with DTS-MA HD
- Some streaming that uses Dolby Digital Plus. I have seen sometimes if you try using digital COAX for Dolby Digital Plus where the sound may have "skipping" problems every few seconds when the processor tries to synch or it may only give you the 2-channel left/right channels. In this case, you must use Dolby Digital Plus over HDMI.
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Feel free to upgrade your bluray player if you want. It might improve the sound a little, but I don’t think it will give you that visceral and spatial imaging you are craving. And the digital COAX will, ultimately, only improve the sound on 2-channel PCM audio and old DVD movies.

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" lack of clear imaging " - heh, I keep recommending this fuse upgrade because it is such a cheap investment, it’s almost a no-brainer. While the Marantz is very excellent at giving a full and true sounding waveform, it is rolling off the upper mids and highs. The fuse would put the audio back into focus and would really improve clarity and spatial imaging. A power cord upgrade can also help here, but it becomes hugely more expensive and it can be difficult to match the proper power cord. Making the highs more clean/clear could help reduce that "fatiguingly bright" effect because a warm sound will actually smear the highs and make them more harsh. Or, it could be that you are just now hearing the problems with those aluminum tweeters on a full range system. Or it could be you are hearing problems with harshness caused by the low cost interconnects, or even low cost stranded speaker wire. lol. Stock power cords can also create a bright/harsh fatiguing sound on a very high resolution system. Welcome to the wonderful world of tweaking audiophile systems.

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For acoustics, if you definitely have a bass resonation in that corner behind the speaker, then putting a GIK Acoustics "Soffit" or "Tri-trap" in that corner will help. You can even stack two to make an 8 foot high bass trap.
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For that particular speaker, I would also put a normal acoustic panel right on the wall just in front of the speaker. This would be a normal 2-3" panel, like the GIK Spot Panel. Since the speaker is only a few inches away from the wall, it actually uses the wall to act like a "horn" that boosts certain frequencies with that first reflection point. Not a good thing, lol. Or I can advise you on how to make your own panel (it’s just some Owens 703 fiberglass that is covered with fabric such as Guilford of Main or something).

Ok, you've successfully twisted my arm about the fuse upgrade! I just opened up the Marantz and pulled the fuse, so I could figure out which to buy.

Looks like it's the 5x20 size.  The circuit board and the etching on the fuse are T2AL/250V... From a bit of Googling, it looks like this means:

T = slow blow
2A = 2 amps
L = glass
250v = rated voltage

My best guess is that I should get this one:
https://www.partsconnexion.com/FUSE-80979.html

Though that one appears to be an extra slow blow. Will that matter? 

I also just read a few reviews and commentary on fuses, and of course started going down the rabbit hole of various other options (and reading lots of arguments about whether fuses are "snake oil" or not...). Anyway, if i'm going to swap out the fuse, I'm willing to spend a few more bucks if it'll be an even more notable improvement.

The fuse isn't particularly easy to get to in the Marantz...have to pull off two covers, and then remove another circuit board. Doable, but it's not something I want to be doing often. So if I can get a better fuse now for a few bucks more...

I saw the Supreme 3 available around some shops for $60 to $75... and then there's the Synergistic Blue for $150...  will spending more on those likely yield any better results?