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Advice about Denon AVR (Denon AVR-X3700H)

loque59

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Hi all,

I'm about to upgrade the AVR of my current 5.1 setup. The speakers are B&W 68x gen 1 with 683 fronts, 686 surround, the big center and the big sub. The receiver that is about to get retired is a NAD T755.

I've been talking to my local hifi store about the new Denon AVRs and got the recommendation to go with the AVR-X4700H; with the main argument that the X3700H may not be able to drive the big fronts.

I am not sure that the difference in power between these two AVRs would make that much of a difference. Although I would like to be able to listen to music with just the 2 fronts with an amplifier that is comfortable enough to bring the speakers to justice. I discussed the possibility to pair the X3700H with a NAD C368 in HT-bypass mode for movies. They seemed to be unaware of this feature and was overall not that keen on this idea.

What do you guys think would be the best setup? I have the possibility to buy it all, try it out for up to 60 days, and return it for a full refund.
 

bravomail

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Hi all,

I'm about to upgrade the AVR of my current 5.1 setup. The speakers are B&W 68x gen 1 with 683 fronts, 686 surround, the big center and the big sub. The receiver that is about to get retired is a NAD T755.

I've been talking to my local hifi store about the new Denon AVRs and got the recommendation to go with the AVR-X4700H; with the main argument that the X3700H may not be able to drive the big fronts.

Store is trying to upsell u. Ignore their advice.
I'd wait til Denon starts replacing their HDMI chip. In older/current AVRs it is buggy - doesn't work with 120Hz 4K HDMI.
Also, Denon replaced AKM DAC chip in those receivers, and we haven't seen that measured. Either take risk, or wait for measurements.
 

Ata

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The difference in wattage between X3700H vs X4700H is unlikely to translate to more than 1-2db max SPL. Unless you need any features of X4700H not present on the lower model, you don't need it.
 
OP
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loque59

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Thanks for your advice! I'll check out about the replaced DAC, haven't seen anything about that.
 

Chrispy

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The difference in power is minimal between the two units, less than 1dB (.8). Both have pre-outs in case you feel you need a more powerful amp for your use....(and I'd simply use a power amp in that case rather than the duplicated features of an integrated amp).
 

mike7877

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Get the 3700, the 4700 has nowhere near 2db more headroom -adding 3db takes twice the power! If I remember right the 3700 puts out 114 watts into 8 ohms and the 4700 puts out 124. About a third of a decibel: practically identical.

I bought both the v1 and v2 receivers (v1 first DAC, v2 second DAC) and I kept v2.

What I heard: DAC in v2: top octave is not as bright and more detailed midrange. v1 was more fatiguing (comparatively, I don't mean to say it's bad, it's not - just a little bright compared to v2 and neutral). I couldn't tell if fatigue was because of more top end or more distortion - at the end of the day it doesn't matter. I went with v2, and you have v2 available.

If you find you want a bit more headroom in the future, bi-amping is always an option - especially with a 5.1 system (with 9 channels you can bi-amp and still even add front heights!).
You probably won't bi amp though, unless you have a huge room and your speakers have nasty low impedance dips in the bass region which cause HF distortion. If you had this problem with the 3700, having the 4700 wouldn't fix anything). I think your speakers are fine though. Reasonably efficient (90db/w) too.

The 3700 can drive some 85db/w speakers I have to very uncomfortable levels in a 20x14 foot room (non bi amped)
 

Chrispy

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Get the 3700, the 4700 has nowhere near 2db more headroom -adding 3db takes twice the power! If I remember right the 3700 puts out 114 watts into 8 ohms and the 4700 puts out 124. About a third of a decibel: practically identical.

I bought both the v1 and v2 receivers (v1 first DAC, v2 second DAC) and I kept v2.

What I heard: DAC in v2: top octave is not as bright and more detailed midrange. v1 was more fatiguing (comparatively, I don't mean to say it's bad, it's not - just a little bright compared to v2 and neutral). I couldn't tell if fatigue was because of more top end or more distortion - at the end of the day it doesn't matter. I went with v2, and you have v2 available.

If you find you want a bit more headroom in the future, bi-amping is always an option - especially with a 5.1 system (with 9 channels you can bi-amp and still even add front heights!).
You probably won't bi amp though, unless you have a huge room and your speakers have nasty low impedance dips in the bass region which cause HF distortion. If you had this problem with the 3700, having the 4700 wouldn't fix anything). I think your speakers are fine though. Reasonably efficient (90db/w) too.

The 3700 can drive some 85db/w speakers I have to very uncomfortable levels in a 20x14 foot room (non bi amped)
Why would avr bi-amp be meaningful?
 

mike7877

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Why would avr bi-amp be meaningful?

I'll do one example using the 3700 specifically.

I made a huge post but it was wordy and not necessary, here is the long condensed version:

You have 8 ohm speakers. The Denon 3700 is measured to make up to 114 watts into 8 ohms before distortion increases.
How many volts does it take into 8 ohms to make 114 watts?
30 volts

So the 3700 can make 30 volts! What happens when you put 30 volts into 4 ohms?
228 watts!
But the 3700 measured 168 watts into 4 ohms!

It can't make 30 volts into 4 ohms :(

Commonly, 8 ohm rated speakers have impedance dips to about 4 ohms in their midbass region - between 100 and 350hz. This region of the audio spectrum contains a lot of energy in music and movies.

Say you're watching a movie and there's an explosion in the lower midbass (among other sounds).

If you have the same signal that peaks at 30 volts being sent to two pairs of outputs instead of one (bi-amping - one amp for woofer, one amp for midrange/tweeter), then:

The woofer will clip and the midrange/tweeter will not.
instead of
The woofer, midrange, and tweeter getting clipped signal.

With bi amping, the explosion will be slightly quieter with all simultaneous sounds unaffected (speech etc is still clear). Using just one channel, speech and other sounds become a garbled mess SOONER

And that's the point
Using just one channel, with increasing volume, speech and other sounds become a garbled mess sooner.

Aside from the benefit of remaining clear to higher levels, when you draw less power from an amplifier (even with the same voltages being generated at the output), distortion is lower. It's not a huge difference, but check out the difference in distortion measurements of amplifiers tested into 8, 4, 2, 1 ohm loads - you'll see.

If you can do it, do it! Always.

Edit: I just added detail to the reason I gave in my original post
 

Chrispy

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I'll do one example using the 3700 specifically.

I made a huge post but it was wordy and not necessary, here is the long condensed version:

You have 8 ohm speakers. The Denon 3700 is measured to make up to 114 watts into 8 ohms before distortion increases.
How many volts does it take into 8 ohms to make 114 watts?
30 volts

So the 3700 can make 30 volts! What happens when you put 30 volts into 4 ohms?
228 watts!
But the 3700 measured 168 watts into 4 ohms!

It can't make 30 volts into 4 ohms :(

Commonly, 8 ohm rated speakers have impedance dips to about 4 ohms in their midbass region - between 100 and 350hz. This region of the audio spectrum contains a lot of energy in music and movies.

Say you're watching a movie and there's an explosion in the lower midbass (among other sounds).

If you have the same signal that peaks at 30 volts being sent to two pairs of outputs instead of one (bi-amping - one amp for woofer, one amp for midrange/tweeter), then:

The woofer will clip and the midrange/tweeter will not.
instead of
The woofer, midrange, and tweeter getting clipped signal.

With bi amping, the explosion will be slightly quieter with all simultaneous sounds unaffected (speech etc is still clear). Using just one channel, speech and other sounds become a garbled mess SOONER

And that's the point
Using just one channel, with increasing volume, speech and other sounds become a garbled mess sooner.

Aside from the benefit of remaining clear to higher levels, when you draw less power from an amplifier (even with the same voltages being generated at the output), distortion is lower. It's not a huge difference, but check out the difference in distortion measurements of amplifiers tested into 8, 4, 2, 1 ohm loads - you'll see.

If you can do it, do it! Always.

Edit: I just added detail to the reason I gave in my original post

Meh. Probably simpler to just get the amp you need in the first place. Actual (active) bi-amping is the only kind I'd bother with. Might try this article
 

mike7877

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Meh. Probably simpler to just get the amp you need in the first place. Actual (active) bi-amping is the only kind I'd bother with. Might try this article

Bi-amping is active. If you mean an active crossover - (filtering the audio first, then amplifying) - that is a higher performance option than bi-amping.

But you can't do that with the 3700, or any receiver in existence to my knowledge. Actually... technically you can. For an active crossover you'd have to use a computer to send a surround signal over HDMI from a computer, with filtered lows sent to "front", mids sent to "surround", and highs to "surround back". Then you'd hook up your woofers to the fronts, midranges to surrounds, and tweeters to surround backs.
You could even send the LFE signal to height 1s and to connect two subs! And if that's not enough, LFE again to the centre channel to hook up one of those fancy couch shakers lol.

I planned to do something like this for a music setup, but no receiver I've come across (in my price range) has a high enough performance DAC. Even really expensive receivers like the Denon 8500 barely make the cut.

Anyway, with all the channels taken this way to drive the fronts there's no surround sound anymore.

Back on topic (I get distracted easily lol).
The 3700 should be powerful enough to drive his 683s. In the slight chance it's not, the next step would be to try bi-amping. It'd result in more headroom than a 4700, and he'd have lower distortion at all levels. As I said, when less power is drawn from any amplifier (even if its output voltage is the same), there is less distortion. So it's a good idea to always bi-amp receivers if they've got the channels to spare
 

Chrispy

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Bi-amping is active. If you mean an active crossover - (filtering the audio first, then amplifying) - that is a higher performance option than bi-amping.

But you can't do that with the 3700, or any receiver in existence to my knowledge. Actually... technically you can. For an active crossover you'd have to use a computer to send a surround signal over HDMI from a computer, with filtered lows sent to "front", mids sent to "surround", and highs to "surround back". Then you'd hook up your woofers to the fronts, midranges to surrounds, and tweeters to surround backs.
You could even send the LFE signal to height 1s and to connect two subs! And if that's not enough, LFE again to the centre channel to hook up one of those fancy couch shakers lol.

I planned to do something like this for a music setup, but no receiver I've come across (in my price range) has a high enough performance DAC. Even really expensive receivers like the Denon 8500 barely make the cut.

Anyway, with all the channels taken this way to drive the fronts there's no surround sound anymore.

Back on topic (I get distracted easily lol).
The 3700 should be powerful enough to drive his 683s. In the slight chance it's not, the next step would be to try bi-amping. It'd result in more headroom than a 4700, and he'd have lower distortion at all levels. As I said, when less power is drawn from any amplifier (even if its output voltage is the same), there is less distortion. So it's a good idea to always bi-amp receivers if they've got the channels to spare

In actual practice it doesn't amount to much. There were a coupla avrs from Onkyo years back that provided an actual bi-amping experience (active bi-amping is the real deal as far as bi-amping goes, passive bi-amping is what avrs can generally only do and is more about marketing). I'd call it more a waste of wire and time. YMMV.

edited to clarify
 
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LTig

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In actual practice it doesn't amount to much. There were a coupla avrs from Onkyo years back that provided an actual bi-amping experience (active bi-amping is the real term, passive bi-amping is what avrs can generally only do). I'd call it more a waste of wire and time. YMMV.
Yep. Instead of using 2 amps with same power better use one amp with twice the power. This will make a real difference.
 

mike7877

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I didn't know the term "active bi-amping" means active crossover. Good to know, I'll use the term here.

I'm interested to know which Onkyo receiver did active bi-amping and how it did it - were the crossover points and driver levels fixed to work with a bundled speaker (like most speakers passive crossovers are)? Or were they switchable to work with a few different speakers in a series designed to work with it? If both were fully customizable, that'd be amazing. I doubt it though, the receiver is probably 20 years old with no DSP, so the filters are probably discrete circuits.

To the topic at hand: you're both still missing my point. I'm not saying passive bi-amping with a receiver doing all 4 channels is as good as passive bi-amping with the receiver doing 2 channels and an external amp doing 2 channels. I'm not saying passive bi-amping (of any combination) will perform as well or better as an amplifier rated for twice the power

I'm saying:
1.) Passive bi-amping results in lower distortion at all levels. When passively bi-amping (with a receiver or otherwise) the higher the level, the more distortion is lowered (compared to a non bi-amped speaker)

2.) Using the bi-amp feature on a receiver results in much lower perceived distortion in the high frequencies when the volume is high and there's a lot of energy in the upper bass region. This is especially so when 8 ohm speakers which dip down below 4 ohms in the upper bass region are used (this is not uncommon, the 683s do)

Explaining #1:
When a woofer is moving, its voice coil is moving through a magnetic gap, generating energy (back EMF). When you (passively) bi-amp a speaker, you electrically separate the woofer from the tweeter (or the woofer from the midrange and tweeter). Why is this a good thing? To deal with the back EMF generated by a woofer, amplifier essentially works in reverse of it, nullifying it.
Just like distortion is generated during signal amplification, distortion is generated nullifying) back EMF.
The more a woofer is moving (the higher the level) the more back EMF is generated. The more back EMF is generated, the more extra work the amplifier has to do to nullify it. When there's no back EMF from the woofer because it's not in the circuit, there's no added distortion from it. And what I said in post 8 and 10.
So: Passive bi-amping results in lower distortion at all levels. When passively bi-amping (with a receiver or otherwise) the higher the level, the more distortion is lowered (compared to non bi-amped)

Explaining #2
See last half of what I wrote in my first post in this thread (post #8). I can't say it any shorter or clearer.

Also, you can meaningfully increase headroom just by passive bi-amping. Most amplifiers are stable down to 3 ohms or less and will put out about 50% more power into 4 ohms than 8 (Denon 3700).
If the Denon 3700 is driving an 8 ohm speaker which is 4 ohms in the treble and 4 ohms in the midbass (B&W 683) with loud, midbass heavy content with crisp, loud highs (30 volts) with 4 channels (2 to woofers, 2 to midranges/tweeters - a passive bi-amp), the highs which would normally be distorted because of too much current being demanded by the woofers at 30 volts, are not distorted. The lows are a bit less distorted because there's about 30% less current being drawn by the midrange/tweeter, and the distortion that is there is not really perceived by the brain because the highs are clear. In addition to the lower distortion, the bass is also a bit louder from the extra current.

I'm not saying its perfect, but I'd estimate (with properly designed good speakers with normal impedance dips) in the worst case, passive bi-amping with the 3700 is as good as adding 25 watts. Depending on the content and a speaker's crossover points and impedance curve, in the best case it could be like adding over 50.

In any case, it's far from being a waste of speaker cable.

Sorry I didn't explain the 30 volts thing I went through in post 8 again. If you don't understand let me know and I'll expand on it
 
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Chrispy

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I didn't know the term "active bi-amping" means active crossover. Good to know, I'll use the term here.

I'm interested to know which Onkyo receiver did active bi-amping and how it did it - were the crossover points and driver levels fixed to work with a bundled speaker (like most speakers passive crossovers are)? Or were they switchable to work with a few different speakers in a series designed to work with it? If both were fully customizable, that'd be amazing. I doubt it though, the receiver is probably 20 years old with no DSP, so the filters are probably discrete circuits.

To the topic at hand: you're both still missing my point. I'm not saying passive bi-amping with a receiver doing all 4 channels is as good as passive bi-amping with the receiver doing 2 channels and an external amp doing 2 channels. I'm not saying passive bi-amping (of any combination) will perform as well or better as an amplifier rated for twice the power

I'm saying:
1.) Passive bi-amping results in lower distortion at all levels. When passively bi-amping (with a receiver or otherwise) the higher the level, the more distortion is lowered (compared to a non bi-amped speaker)

2.) Using the bi-amp feature on a receiver results in much lower perceived distortion in the high frequencies when the volume is high and there's a lot of energy in the upper bass region. This is especially so when 8 ohm speakers which dip down below 4 ohms in the upper bass region are used (this is not uncommon, the 683s do)

Explaining #1:
When a woofer is moving, its voice coil is moving through a magnetic gap, generating energy (back EMF). When you (passively) bi-amp a speaker, you electrically separate the woofer from the tweeter (or the woofer from the midrange and tweeter). Why is this a good thing? To deal with the back EMF generated by a woofer, amplifier essentially works in reverse of it, nullifying it.
Just like distortion is generated during signal amplification, distortion is generated nullifying) back EMF.
The more a woofer is moving (the higher the level) the more back EMF is generated. The more back EMF is generated, the more extra work the amplifier has to do to nullify it. When there's no back EMF from the woofer because it's not in the circuit, there's no added distortion from it. And what I said in post 8 and 10.
So: Passive bi-amping results in lower distortion at all levels. When passively bi-amping (with a receiver or otherwise) the higher the level, the more distortion is lowered (compared to non bi-amped)

Explaining #2
See last half of what I wrote in my first post in this thread (post #8). I can't say it any shorter or clearer.

Also, you can meaningfully increase headroom just by passive bi-amping. Most amplifiers are stable down to 3 ohms or less and will put out about 50% more power into 4 ohms than 8 (Denon 3700).
If the Denon 3700 is driving an 8 ohm speaker which is 4 ohms in the treble and 4 ohms in the midbass (B&W 683) with loud, midbass heavy content with crisp, loud highs (30 volts) with 4 channels (2 to woofers, 2 to midranges/tweeters - a passive bi-amp), the highs which would normally be distorted because of too much current being demanded by the woofers at 30 volts, are not distorted. The lows are a bit less distorted because there's about 30% less current being drawn by the midrange/tweeter, and the distortion that is there is not really perceived by the brain because the highs are clear. In addition to the lower distortion, the bass is also a bit louder from the extra current.

I'm not saying its perfect, but I'd estimate in the worst case, passive bi-amping with the 3700 is as good as adding 25 watts to its output. Depending on the content it could be like adding 50.
It's very, very far from being a waste of speaker cable.

Sorry I didn't explain the 30 volts thing I went through in post 8 again. If you don't understand let me know and I'll expand on it
Unless you remove a passive crossover from a speaker, it will simply be passive bi-amping with either an avr/single power supply to even separate amps/power supplies. Not much to be had in either of those ways, tho. Effect of emf is generally overstated IMO. Just get a better amp to start is a much better approach, if it's even an issue in your use.

The Onkyo 818 and 929 had the variable active crossover points (not completely variable IIRC, but a fairly wide choice) for a pair of 2 way speakers. I considered one at the time to play with diy stuff, where bi-amping may be meaningful (vs getting better results from a well designed speaker for using a specific passive crossover by simply using an active crossover, even if you did remove the passive crossover).
 

mike7877

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Unless you remove a passive crossover from a speaker, it will simply be passive bi-amping with either an avr/single power supply to even separate amps/power supplies. Not much to be had in either of those ways, tho. Effect of emf is generally overstated IMO. Just get a better amp to start is a much better approach, if it's even an issue in your use.

The Onkyo 818 and 929 had the variable active crossover points (not completely variable IIRC, but a fairly wide choice) for a pair of 2 way speakers. I considered one at the time to play with diy stuff, where bi-amping may be meaningful (vs getting better results from a well designed speaker for using a specific passive crossover by simply using an active crossover, even if you did remove the passive crossover).

What I'm saying is the 3700 should be fine for the 683s, and (passive) bi-amping would more than make up the 10 watt difference between it and the 4700

Edit: back EMF can easily add 50% to power dissipation. 50% to distortion? Probably
 

amper42

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The reason I went with the Denon 4700 is it offers Auro-3D with up mixer while the 3700 does not. It also has a front HDMI port I find convenient for plugging in during REW testing and dual +12 trigger outs. Gold plated RCA, bigger power supply, bigger dual line display, 20W more power are all nice too but less important compared to Auro-3D for my use. Come to think of it I would miss the dual line display. :D
 

mike7877

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The reason I went with the Denon 4700 is it offers Auro-3D with up mixer while the 3700 does not. It also has a front HDMI port I find convenient for plugging in during REW testing and dual +12 trigger outs. Gold plated RCA, bigger power supply, bigger dual line display, 20W more power are all nice too but less important compared to Auro-3D for my use. Come to think of it I would miss the dual line display. :D

Something interesting for you to try, since you like to tweak things.

I have my 3700 and had a 750 before it. The 750 had a 400 watt rating on the back, the 3700 has a 660 watt rating on the back.

When you draw more than half of the rating printed on the back from the wall for more than 5 minutes a relay clicks limiting voltage to the transistors like Eco mode, but eco mode doesn't visibly come on. I think it's transformer protection. It doesn't matter if you make it take 200/330 (750/3700) watts from the wall by driving 2 channels or 9 channels: once you're there for a while, a relay clicks and peak voltage goes down from 60 volts to 25. Or whatever eco limits it to.

I think your 4700 has 700w printed on the back, so your limit should be 350 watts from the wall for a few minutes.

It's very easy to get 350 from the wall, you'll be surprised. In non eco mode, 40 watts at at the speaker terminals should do it. I like subsonic sines into sealed speakers for this purpose

Classic rock can be turned up to about 12wRMS per channel on any 100w per channel amp before clipping sets in (give or take 5w). Yes, the peaks really are that high, and yes, the average power really is that low. It's a fact, I've verified with my killa watt, scope, and 8 ohm dummy load. That 12 watt stereo signal will have your 4700 taking over 200 extra watts from the wall. Good news is if you turn it down 3db and turn on eco mode, that 200 watts drops not to 100 watts, but like 30 watts (all numbers on top of the 60/100 watts or so drawn at idle in eco/non eco modes).

On the 750 eco mode had a detrimental effect on sound quality, clarity suffered - one very obvious defect was distortion added to the apple tv sounds when moving through menus. The upper tier receivers don't have this problem fortunately.

Anyway, try it out! I'm curious to see if all Denon receivers are limited to taking 50% of their power consumption rating from the wall. Keep in mind, you have 5 minutes at or above 350 watts (wall) until hidden eco kicks in. I've tested short term duration, the 750 can take over 700 watts from the wall. So the receivers are fine for transients (movies are mostly quiet with a few loud sounds here and there, these are devices for movies). These just are not designed for long term high power output on all their channels. I wonder why no reviews mention this phenomenon??

When you think about it, the transformers are only like 10-15lbs. They would overheat and burn if 700 watts went through them continuously.

Edit: If anyone wants a free extra 20 watts to listen to a few loud songs, just turn your variac up to 132 volts! It works lol. Just don't leave it there when you're not listening to loud music. And maybe use a fan if a few loud songs turns into many. You don't want heat damage!!
I'm joking, don't do this!!! If the power capacitors are specd for 63v and your transformer gives them 63v with a 120v supply, any voltage higher than 120 can damage your caps. Good practice is to use 75-80v caps for 60-65v rails, but manufacturers have been known to cheap out so you could break your badly designed device
 
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amper42

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Something interesting for you to try, since you like to tweak things.

I have my 3700 and had a 750 before it. The 750 had a 400 watt rating on the back, the 3700 has a 660 watt rating on the back.

When you draw more than half of the rating printed on the back from the wall for more than 5 minutes a relay clicks limiting voltage to the transistors like Eco mode, but eco mode doesn't visibly come on. I think it's transformer protection. It doesn't matter if you make it take 200/330 watts from the wall by driving 2 channels or 9 channels: once you're there for a while, a relay clicks and peak voltage goes down from 60 volts to 25. Or whatever eco limits it to.

I think your 4700 has 700w printed on the back, so your limit should be 350 watts from the wall for a few minutes.

It's very easy to get 350 from the wall, you'll be surprised. In non eco mode, 40 watts at at the speaker terminals should do it. I like subsonic sines into sealed speakers for this purpose

Classic rock can be turned up to about 12wRMS per channel on any 100w per channel amp before clipping sets in (give or take 5w). Yes, the peaks really are that high, and yes, the average power really is that low. It's a fact, I've verified with my killa watt, scope, and 8 ohm dummy load. That 12 watt stereo signal will have your 4700 taking over 200 extra watts from the wall. Good news is if you turn it down 3db and turn on eco mode, that 200 watts drops not to 100 watts, but like 30 watts (all numbers on top of the 60/100 watts or so drawn at idle in eco/non eco modes).

On the 750 eco mode had a detrimental effect on sound quality, clarity suffered - distortion was added to apple tv sounds when moving through menus. The upper tier receivers don't have this problem fortunately.

Anyway, try it out! I'm curious to see if all Denon receivers are limited to taking 50% of their power consumption rating from the wall. Keep in mind, you have 5 minutes at or above 300 watts until hidden eco kicks in. I've tested short term duration, the 750 can take over 700 watts from the wall. So the receivers are fine for transients (movies are mostly quiet with a few loud sounds here and there). These just are not designed for long term high power output.

When you think about it, the transformers are only like 10-15lbs. They would overheat and burn if 700 watts went through them continuously

I use the Denon 4700 in full pre-out mode. The internal Denon amps are always off. The unit has a 710W power supply but in full pre-out mode the 4700 only uses 46W no matter how many channels are in use or how loud it's playing. I have a 7.2.4 configuration with Monolith 7x200 on the fronts, center and surrounds and an Adcom 5-channel on the height speakers. I plan to configure all 11 channels with NC502MP amps soon. Full pre-out mode offers lots of upgrades and simply using the Denon 4700 as a pre-amp/processor provides higher 97dB SINAD performance.

Bottom line, your concerns about power limitations completely disappear with full pre-out mode.

4700-back.jpg


As you can see below, turning off ALL internal Denon 4700 amps offers a significantly improved path in SINAD performance curve when exceeding 1.4V. Leaving any of the internal amps on can substantially increase distortion by the time 1.8V is achieved.

Denon AVR-X4700H 8K Home Theater Receiver AVR Dolby Atmos Surround HDMI THD+N vs Output Level ...png
 
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mike7877

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I use the Denon 4700 in full pre-amp mode. The internal Denon amps are always off. The unit has a 710W power supply but in full pre-amp mode the 4700 only uses 46W no matter how many channels are in use or how loud it's playing. I have a 7.2.4 configuration with Monolith 7x200 on the fronts, center and surrounds and an Adcom 5-channel on the height speakers. I plan to configure all 11 channels with NC502MP amps soon. Full pre-amp mode offers lots of upgrades and simply using the Denon 4700 as a pre-amp/processor provides higher 97dB SINAD performance.

Bottom line, your concerns about power limitations completely disappear with full pre-amp mode.

View attachment 158246

They also disappear for everyone using the 4700 as intended - to watch movies or listen to loud music in one room, or music at moderate levels in 2-3 rooms.

I'm not saying Denon receivers are useless, I'm saying an interesting experiment to try is making it pull just over 355 watts from the wall and checking if the hidden eco mode I described enables itself. I've only checked two models, but at exactly half the power listed on the back of each leads me to believe it's a thing
 

mike7877

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The average power to surrounds is ridiculously low. Even with explosions and stuff, the 4700 should be fine to run all of your surrounds, unless you have a massive room or very very inefficient speakers. Before you go and buy more amps, have you tried using your 4700 to power your surrounds? You should, it probably can do an excellent job. Then just sell your multi channel amps and buy 3 nice amps to run in bridge mode to power your fronts with unlimited clear power
 
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