Getting back to AV

Thanks! Looking forward to it.

I've got dangerously sidetracked onto stereo amps now... It's a slippery slope!

Currently thinking I'll aim for a pre/power setup, with the Yamaha and stereo pre-amp switched at the power amp input. Easy enough to do in stages.

I'll start out by running it into the Rotel's aux input, but I'm expecting the Rotel to struggle driving the Q55.2s in this room anyway - and even allowing that Rotel's power figures are likely a good deal more conservative than Yamaha's there's going to be a significant mismatch between 30W on the front channels and 70/80W on the surrounds.
 
Not sure if this helps but i have ran a arcam avr 400 for yrs now. No 4k atmos etc but has hdmi switching dts ma and true hd and sounds great for music and film. I got rid of my separate roksan and denon system for this and still happy now they can be picked up at a good price now a great amp for the money
 
Well, got caught looking at amps on eBay earlier... and still slightly shocked that I've been given the green light to upgrade the stereo amp. So, Rotel pre and power amps on the way. Nothing that's going to get anyone on here hugely excited, but it should be a significant step up from what I currently have.

The power amp is six channel, so I've got a few options there - I could just use two of then for the front channels, bridge two pairs, or bi-amp them. Then I can either leave the Yamaha running the centre channel it run that through the Rotel with the same options. Playtime! 🙂

I've only catered for a single channel to each speaker when I ran the wires, but I left the front overhead channels long enough to reach the front in case I ever installed up firing ATMOS speakers. So I could use them to bi-amp. Not sure if I can manage a second channel for the centre without joining wires in the loft - not ideal, but not the end of the world either.

The more I look at the shape of the ceiling in this room the more dubious I am that ATMOS would work in it anyway - pretty certain four overhead channels in the right places is a no go, not sure if two would work - and as I've allowed for 7.x.4 even if I use three of the channels I ran for potential future ATMOS use I'd still have enough for either 7.x or 5.x.2.

Think I need to post some diagrams of the room and figure out what would and wouldn't work.
 
So, long story short, when the Rotel amps arrived (some time back now), the power amp had taken a bit of a battering in transit - dented case (looked worse than the photo, but straightened out reasonably well) and more seriously the binding posts pushed in and cracked:
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After straightening things out enough that the binding posts weren't in contact with anything they shouldn't be, I tested the amp and it still worked fine, so negotiated a partial refund with the eBay vendor and opted to keep it.

The original binding posts are nothing special, and as far as I can tell aren't available as a spare part (this amp is about 20 years old), so I purchased some generic binding posts off Amazon - broken original on the right, replacements on the left:
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The original posts are screwed to the terminals and poke through holes in the back plate, which they are then screwed to after the back plate is in place. I couldn't find anything which was going to quite work in the same way or was large enough to secure in the holes in the back panel, so the thinking here was that paired posts would clamp onto the back panel bridging two of the post holes. They'd need to be fixed to the panel first and then the terminals once the panel was in place, which was going to be a bit fiddly, but looked workable.

The new posts stuck out further internally, so first thing was a trial fit to make sure they didn't foul anything. Looked okay on that front, but revealed something I'd missed:
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Yup, the terminals don't have round holes - they have flats, as do the original binding posts, which stop everything rotating when you're doing them up. Nice design, but doesn't play nicely with the standard round replacements...

I considered drilling out the terminals, but I'd have had to do it in-situ and I didn't fancy my chances of keeping swarf out of the amp. I also had concerns about breaching the gold plating.

So, after some head scratching, plan B - I discovered I could assemble a combination of bits from the old and new binding posts to finish up with something that clamped the back panel but also fitted the existing terminals. Basically used the centres of the original posts passing through the mountings for the new ones. To get this to work I had to wind the clamps right out exposing the thicker area with the hole for a bare speaker wire, which was the right size to locate in the mountings and left the post long enough internally to reach the terminals. There's no way with this arrangement to clamp the posts securely to the back panel before fitting it, which is...awkward...but once assembled the only real downside is you can no longer use bare wires. No problem, I use banana plugs anyway and they still fit fine.

I had to hold everything together with masking tape to get it in place, and then fit the nuts to the binding posts without easy access:
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But ultimately success - it all fits nicely:
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You have to look twice at the end result to see it's not standard:
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So, I'm happy enough with that. Now I just need to finish running the speaker wire!
 

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And there's been some progress on the wiring front. After clearing out all the old rodent infested loft insulation - a delightful job, but definitely necessary, because this:
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Had been up to this:
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I've sorted out the tangle of wires I left in the loft a couple of months ago:
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And run them all tidily where they need to go:
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The ones that aren't future proofing are now hanging down behind the living room wall ready to be pulled through when I'm allowed (which will be when the spare room and office are finished...).

The loft is reinsulated and partially rat proofed - still got some more work to do there.
 
Well, the office and spare bedroom have been done for a while, and it is now when the kitchen is done ;)

But, I have got the hi-fi up and running using the rear channels. I bought new racks a while back (the old black steel one didn't have enough shelves, and has never been popular with my wife).

First problem was that the power amp didn't fit once there were plugs in the back. A little surgery later that problem was solved...

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... and I got everything connected - with some difficulty, 1m interconnects aren't long enough on this closed rack. I've bought some 2m ones, but not fitted them yet.

At the moment I've got:
Rega Planar 2 with NAD pre-amp.
Denon DRW-650.
Marantz CD52.
Rotel RC-972.
Rotel RB-976.

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The Yamaha processor isn't in use yet, as the TV and blueray player are on the other side of the room and I haven't cut patrices into the wall and pulled anything through yet. That's also where the main speakers are, so for now I've a six channel power amp driving a pair of Kef Q85s surround speakers. No bass (they roll off at 120Hz), but they actually sound okay with carefully selected music - and a lot better than nothing!

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I've got a Marantz CD30SE, Technics RS-TR355 and Denon TU-260L sat here as well, but there seems little point experimenting with inputs until I'm running the main speakers. The CD52 isn't likely to be a long term keeper, as the tray clatters in and out, though it works fine once the disk is in. I'm not sure the CD30 has that much life in it either, though.
 
The other thing to experiment with once the main speakers are connected is running the stereo sources through the Yamaha. If that sounds as good as the Rotel preamp then it simplifies things, so it's worth trying - I'll be surprised if it does, though. Assuming I'm keeping both, I'll ideally need to sort out a switch to select the preamp on the front channels.
 
So, unsurprisingly the tray on the CD-52 has got steadily worse and is now pretty much unusable. It's a cheap fix, but for now I've dropped the other player in - a Marantz CD-50 SE (not CD-30 as I'd misremembered). Which one I'll keep I really don't know. Over the surround speakers and the headphones I recently added (Sennheiser HDR 120 II, so nothing special) I can't hear any difference. The CD-50 is a more modern looking machine, although it's the older model - the CD-52 has a rather dated and frankly pretty ugly design, and a more cluttered display. Both have the same Phillips CD-4 transport (so I'm likely to have to fix that either way), the CD-52 has a newer generation of DAC, but it's the stock MK1 and the CD-50 is a special edition so I'm not even sure I'll be able to hear a difference when the main speakers are connected... Just going to have to wait and see, I guess!
 
So, another year and a half on, with a great deal of life getting in the way, and I've finally had a chance to cut some patrices into the wall and pull through the speaker and coax cables. I now have the main speakers connected.

On the whole, pretty pleased given the youngest kit here is over twenty years old. It still sounds good. Both the Q55.2s are closer than ideal to the wall, and one is in the corner moving that one forward into the room noticeably helps stop wooly bass swamping the treble, but that puts it in front of the patio door so isn't really a usable everyday solution. The Kefs have rear ports, so finding some foam bungs for them may help.

Also had to go shopping as it turns out the Panasonic blue ray player/HD recorderonly has HDMI output... how did I miss that...? Even if I still had access to run it, the run is too long for HDMI without at least two powered repeaters, which was why I ran coax. So, cheap ARC compatible audio extractor bought (A Linkfor DAC108). Can't tell if it works yet...

I guess next stop is to get the Yamaha DSP-E800 @HeadBanger gave me hooked up and have a play with that.

That and play with bi-wiring and bi-amping or bridging amps on the front speakers. At the sound levels I listen (relatively low three days), I'm predicting that bi-amping won't make any audible difference - but with long runs of AWG16 speaker cable, bi-wiring might. We'll see...
 
Even if I still had access to run it, the run is too long for HDMI without at least two powered repeaters, which was why I ran coax. So, cheap ARC compatible audio extractor bought (A Linkfor DAC108). Can't tell if it works yet...
So, I see that isn't actually true any more - it should be possible to do the whole run with a single optical HDMI now (albeit for a price). Though I'd still need an audio extractor in order to feed the signal into the Yamaha. I fear a significantly higher obstacle would be getting permission to do as much damage as it would take to access parts of the cable run again :nono:
 
Got the Yamaha wired up yesterday and playing a stereo source. Nothing from the TV, but there are multiple things that could be wrong there:
  1. TV set up wrong (likely)
  2. Audio extractor doesn't work (cheap Chinese unit - quite possible)
  3. Coax run is too long for the signal
And it could be more than one of them... So when I can grab the time I need to sit down with the TV manual, see if I can find a source with coax output in the loft, and trouble shoot it.

At the moment I've got the Yamaha running the main and centre speakers through the power amp and the rear surrounds directly - the surrounds are a lot louder than the front speakers but I haven't balanced the levels yet, so we'll see whether there's enough adjustment. I suspect that even though the Yamaha's manual says to connect the main channels to a 'power amplifier', the outputs are actually line level designed to go into a pre-amp (which would make sense given the target market for this unit - doubt there were many (any?) stereo amps around at the time with pass through inputs, and users with integrated amps would have been a vastly larger market than those with separate pre and power but also not wanting to put in separate AV system. If I end up running it via the pre-amp it at least means I won't need a switch.
 
After some playing around last night - the outputs on the Yamaha are definitely live level. Couldn't even get close to balancing the test tone volumes with the surrounds running from the Yamaha and the fronts and centres through the Rotel power amp.

So, now have surrounds and centre off the Yamaha's internal amps, and the mains into an input on the Rotel Preamp. With the surrounds on their minimum setting (that actually does anything - there's one lower that displays "Min level" or something to that effect, but is actually off) and the centre close to minimum it still needs a fair bit of volume on the Rotels. I guess it might be preferable to leave the other channels higher and wind the Rotels up to match, but if I do that it's going to be deafening when someone forgets to turn it down before switching to a different source....
 
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So, nothing on HDMI ARC. As far as I can see there should be. But, TV has an optical SPDIF output, and the audio extractor has an input for it, so tried that.

Success... sort of.

I've got a signal to the Yamaha, I've got sound. First DVD I tried (Fifth Element - Dolby Digital not DTS) came up as Dolby Digital on the amp, but with the centre channel mixed into the main speakers (nothing from the centre). Switching the amp to Pro Logic enabled the centre, and I've checked it's set to use it. Tried a TV film, Blue Ray and later DTS DVD - all detected as Pro Logic (yes, I did check it was back on auto, and tried to manually set it to DTS - no sound when I did that.

Put the first DVD back in - and can only get Pro Logic on that now...

So, have I done something dumb on the amp (logical, but as far as I can see I haven't), or is it something to do with the audio extractor...? As far as I'm aware, an SPDIF source has no way of detecting what's going on at the other end, so I don't think changing settings on the amp should have had any effect on it, suppose it's possible I gave it a signal from the TV it couldn't handle and made it switch down (though it's supposed to be able to handle everything I threw at it).

Guess the other thing to try is putting it in between the Blue Ray/HDR and the TV on HDMI and seeing if that works. Wouldn't be quite as convenient, but no great hardship to watch via that if we want surround sound - it does everything the TV does.
 
Guess the other thing to try is putting it in between the Blue Ray/HDR and the TV on HDMI and seeing if that works.
Which it won't - because the audio extractor I bought is ARC only, it doesn't do pass through HDMI :facepalm:

I might have a source with Dolby Digital output over coax in the loft, in which case I can test the coax cable and amp - though it's not going to get the kit we're using working any better, it'll just confirm whether there're any problems there (doesn't seem likely - I can't see why if the coax run was too long I'd still have a Pro Logic signal). With what I have available I don't have any way to determine whether the TV or audio extractor are responsible for limiting the signal, assuming it's one of them.

In any case, given when it briefly managed Dolby Digital there was no centre speaker it's actually overall better on Pro Logic. And a huge improvement over the TV speakers...!

Even though Dolby Digital/DTS would be an improvement, adding a sub would make a much bigger difference - the Q55.2s go down to 40Hz according to the spec, so not too bad, but the lack of LFE channel is definitely noticeable. Wonder when I can sneak that upgrade in....? :clown:
 
Both the Q55.2s are closer than ideal to the wall, and one is in the corner moving that one forward into the room noticeably helps stop wooly bass swamping the treble, but that puts it in front of the patio door so isn't really a usable everyday solution. The Kefs have rear ports, so finding some foam bungs for them may help.
So, had another chance to spend an evening playing. Bungs (okay, rolled up socks from the rag box...) have sorted the bass issues. Sounds really good - especially given the age of the components and the modest outlay (at least recently - the speakers long ago paid for themselves). Stereo imaging is far better than any setup I've had before. Ideally I'd prefer a slightly crisper sound, but I'd probably have to spend a good bit more to achieve it.

That and play with bi-wiring and bi-amping or bridging amps on the front speakers. At the sound levels I listen (relatively low three days), I'm predicting that bi-amping won't make any audible difference - but with long runs of AWG16 speaker cable, bi-wiring might. We'll see...

Made up the extra cables needed to bi-amp the Q55.2s using another pair of channels in the RB-976. Quite frankly I can't hear any difference, even with one speaker bi-amped and the other running from a single channel and pair of wires. So logically just bi-wiring wouldn't make an audible difference either.

Still, it's bi-amped now so it's staying that way...because why not?
 
Still, it's bi-amped now so it's staying that way...because why not?
Well, I guess I shouldn't really leave that kicking around the 'net without putting on record that I maybe have found why not...

Just before Christmas my wife and son decided to put some music on. After spending some time fiddling with random controls and cursing me for not just having something with one button to turn it on, they finally got music - fairly loud music from what I can gather. And shortly after that they noticed a smell of very hot electronics and turned it off again...

When I got home and investigated, the pair of channels on the RB-976 that were running the high/mid speaker inputs were dead. My theory - no way to know if I'm right or if it was just coincidence - is that the high/mid stages by themselves weren't high enough impedance for the amp (I can't find anything that states what the impedance of each stage of the Q55.2s is, only the overall impedance).

Rewired so I'm back to using a single pair of amp channels and single pair of speaker wires on each speaker.

So, potentially a caution for anyone else playing around like this!
 

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