Denon AVR-X4800H AVR Review

[Dj7675]

I would never get any D+M AVRs to 0 dB volume, the closest I would, and had ever tried was about -10, might have crank to 0 for a couple second just to experience reference level but wouldn't want to risk damaging my hearing any further.

If you meant volume at -4, and was getting 75 dB at MLP, then maybe something else is wrong. For you, it should be easy to check, because you know your stuff. Regardless, you know every time you double your distance, ignoring room gain, you lose 6 dB spl, you know your speaker's (use one channel at a time only) sensitivity, so you should know the spl you should be getting at your mlp at volume 0, if you have done your autosetup/audyssey right, your should be getting approximately 85 dB average.

Now if you measure your spl if Dirac Live in use, then you will likely be getting about 75 dB, +/- a few dB, because irrc., @Dj7675 told me DL would reserve 10-15 dB.

Again, don't worry about Denon AVR's pre out voltage, they are fine, 3.5 V clean output is not an issue at all.

I believe it is 10dB. DL does not allow more than 10dB boost. At least that is my understanding and experience. Others can correct me if I am wrong.

 

[Oddball]

I believe it is 10dB. DL does not allow more than 10dB boost. At least that is my understanding and experience. Others can correct me if I am wrong.

Isn't it 12dB for ART? Not sure if that is now also true for DL - as 10dB seems more than enough. For low end seems like there are people that might want more than +12dB. Them bassheads . But for now this is all they get.

 

[Dj7675]

Isn't it 12dB for ART? Not sure if that is now also true for DL - as 10dB seems more than enough. For low end seems like there are people that might want more than +12dB. Them bassheads . But for now this is all they get.

Certainly could be and I have seen that number floating around. Anyone tried doing a +12dB curve to see if Art will do that level?

 

[Oddball]

Certainly could be and I have seen that number floating around. Anyone tried doing a +12dB curve to see if Art will do that level?

I did try and use it sometimes on older movies - or when I feel like shaking things a bit. If you put in +12dB shelf or curve, does not necessarily mean you will get +12dB output. Will depend on various factors - but ART will try its best to boost as much as possible in this case.

Also that is for subs. Not advisable to boost the mains that much. Mine are pretty sturdy but don't go beyond +7 on low end and that is for 50hz and above range. ART seems to phase them in audibly at around 60hz though. I know from pre-ART time that they can take that easily for -10dB to reference that is my usual listening volume.

 

[Dj7675]

I did try and use it sometimes on older movies - or when I feel like shaking things a bit. If you put in +12dB shelf or curve, does not necessarily mean you will get +12dB output. Will depend on various factors - but ART will try its best to boost as much as possible in this case.

Also that is for subs. Not advisable to boost the mains that much. Mine are pretty sturdy but don't go beyond +7 on low end and that is for 50hz and above range. ART seems to phase them in audibly at around 60hz though. I know from pre-ART time that they can take that easily for -10dB to reference that is my usual listening volume.

My question would be, if subs were capable of that boost, would ART do it and has anyone done any post measurements showing it would do +12dB?

 

[Oddball]

I have not done it. Lazy dog and penguin is even worse .

The only member I could think off would be @kawauso. She uses +12dB curve with her monster subs and also could have been so diligent to measure it.

 

[dlaloum]

Your assumption is good, the X3000 and X4000 series used to share the same power amp schematics, now the X4800H has the same schematics as the AVR-X8500H, X6700H and SR8015 while the X3800H still uses the same as the X4700H's. So the X4800H/X6800H and Cinema 30 now have the same power amp design, but of course only the Cinema 30 has a more robust power supply, such as higher current capabilities. As far as "topology" they are all just hifi class AB.



I would say if that's the case, use an external fan. The AVR-X4800H has enough juice for your speakers when use on real world stuff, ie movies and music but for certain contents (that might happen to overlap with the impedance dip frequency range a lot), it might heat up enough to shorten it's life, that's when a fan will help a lot.


Or you can just do your own calculations to figure out if you can get away with not using the Crown amp. For me, I would just need to know:

a) the impedance/phase angle curve of your LCR, just pick the one that has the worse impedance/phase angle.
b) as a) above but the sensitivity.
c) your mlp distance from the LCR, or the surround/height speakers if they are the furthest away.
d) your required spl, reference level, or 5 to 10 dB below reference is the highest you would listen to.

For a), just the nominal impedance and the minimum would be fine, without the curves, if you are okay with estimating the "power" need based on the worst case, i.e. conservative scenario.

a) 1.63 ohm (but it is on the tweeter, so load is not excessive) - 3ohm on the woofer XO - phase angle would require some more research
b) 86db
c) circa 2.5 m (height speakers are further away... it is a very tall room)
d) 75db +20db headroom

My estimated power requirements are not onerous... calculated for 8ohm it is around 3.5W for LCR and 16W for peak allowance!! (from memory without doing a detailed analysis / recalc) - which as long as the amp is stable into the speakers reactive load, doesn't really need anything huge.
From memory, moving it to 85db ref, raised the peak requ's to around 70W

 

[dlaloum]

I have not done it. Lazy dog and penguin is even worse .

The only member I could think off would be @kawauso. She uses +12dB curve with her monster subs and also could have been so diligent to measure it.

You can also achieve +12db by using manual target, and setting the mid point (1khz) at (as an example) -6db - then putting the bass at +6db will give you a 12db difference... (rest of curve obviously needs to be adjusted accordingly)

After all, it is ultimately about differences to the reference point - which is normally 1khz - and 1khz need not be nominal 0

 

[Oddball]

You can also achieve +12db by using manual target, and setting the mid point (1khz) at (as an example) -6db - then putting the bass at +6db will give you a 12db difference... (rest of curve obviously needs to be adjusted accordingly)

After all, it is ultimately about differences to the reference point - which is normally 1khz - and 1khz need not be nominal 0

Yes one could do that. But that would reduce the SPL, which might or might not be relevant.

 

[dlaloum]

Yes one could do that. But that would reduce the SPL, which might or might not be relevant.

Your SPL are driven by the AVP/AVR master volume level... not the relative settings of the Dirac Target...

So the question then becomes ... does the system have enough gain as a preamp, after the signal exits the DSP stage.

Honestly that should not be an issue - there should be plenty there - but someone should try it!

 

[Oddball]

Your SPL are driven by the AVP/AVR master volume level... not the relative settings of the Dirac Target...

So the question then becomes ... does the system have enough gain as a preamp, after the signal exits the DSP stage.

Honestly that should not be an issue - there should be plenty there - but someone should try it!

I wish there are infinite resources. I can get +5dB master volume with +12dB low end curve. So math seems to add up. SPL is a function of trims and master volume, and any additional DSP settings you have in chain. Max +5dB level in my system is pretty much when all the hell gets loose though. Not a listening level at all. More like a show off or exploration thing.

But I could not make it louder if I don't add additional DSP in the chain. As I posted before, I tried max from my system and added around +12dB on subs via their DSP. That was extremely violent experience that even covered any rattling sounds in the room - as it was so loud and overpowering. 2 hours a day for that exposure and probably in a month your hearing gets seriously impaired though. Did not measure the peaks as it was a spur of the moment, but likely around 130dB.

Amps are perfectly matched to the AVP. And that is why they are limited to exactly the right level. In case that I had variable gain, Dirac would reduce the output on those channels. Dirac will not allow you to blow up you system by using their tools.

 

[Dj7675]

You can also achieve +12db by using manual target, and setting the mid point (1khz) at (as an example) -6db - then putting the bass at +6db will give you a 12db difference... (rest of curve obviously needs to be adjusted accordingly)

After all, it is ultimately about differences to the reference point - which is normally 1khz - and 1khz need not be nominal 0

This is probably a good strategy if you do full range EQ. I tend to not do that. After many a/b for some reason always seem to prefer not full range correction. Will try it again once my new system gets set up.

 

[dlaloum]

@kawauso as promised!