Advice about Denon AVR (Denon AVR-X3700H)

[mike7877]

What'd be really nice is if receivers had assignable digital outs, at least 2. Then you could send fronts to one, centre to another, and hook up some well designed DACs with 106db SNR or better (imperceptible from perfect at reasonable listening levels). 90 or better for surrounds is more than good enough so overkill for upgraded DACs

 

[Alice of Old Vincennes]

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.

Oh my. Watts and dB. Let's forget about reserves and current.

 

[Alice of Old Vincennes]

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

Don't bridge. Buy mono to resist the urge if addicted.

 

[mike7877]

Don't bridge. Buy mono to resist the urge if addicted.

Yes, bridging degrades performance slightly but the THD+n of the DAC he's using is -97db. If the amps are good, they'll still be transparent. I suggested what I did because he is planning to use very high powered class D amps for all channels.

Oh my. Watts and dB. Let's forget about reserves and current.

Yeah, 660w transformer and 710w transformer, half a pound difference in weight. Lots of reserves in the 4700. The 3700 does 114 watts, the 4700 124 watts (into 8 ohms). More like half a db. The amps are basically identical.

You might be interested to know that I tested both the 750 and 3700 and they can pull exactly half of the power printed on the back from the wall for 5 minutes straight before they go into hidden Eco mode (output rails switch to lower voltage and power consumption goes down). Short term they can take 50-70% more from the wall (~700-1100w for explosions and stuff, I'm sure distortion rises during these massive multi channel transients, but who cares? they're always gunshots or explosions, you can't hear it. I've never heard something come out of ALL speakers at the same time at the highest level either, so)

The power supplies and heatsinks are designed for playing movies and 2 channel music at reasonable levels in rooms up to 14x22 feet. And multi room amplification at levels appropriate for typical 6-8" in wall speakers. Their weight is a good indicator of this

 

[jesper2200]

Hi. I would not worry - both amps could drive your front speakers. I have the B&W CM9 connected to X3700H and it sounds great. But...I wanted to have a 7.1.4 (11.1) setup, so I added an extra power amplifier; Now I have the Denon x3700h and added a refurbished Denon POA-2200 power amplifier using the pre front out (2x 250 watt in 8ohm) to drive my 2 B&W CM9 front speakers. So the setup is now 11.1 (7.1.4) and it sounds fantastic.

Wha´t setup did you choose?

 

[itz_all_about_the_music]

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.

View attachment 158246

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.

View attachment 158250

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.

View attachment 158246

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.

View attachment 158250

I also use a Denon AVR as a pre-pro (AVR-X4000).

Q: When you wrote "...turning off ALL...amps", do you mean a Setting to formally achieve that, or simply have no load(s) on any Outputs? I assume the latter, but it's been some years since my initial calibration and don't recall if "turning off" is a formal Setting. (I'm also assuming such firmware operation has not changed in Denon's designs spanning the two products in this discussiion (i.e., your 4700 and my 4000). Of course I could be wrong and may consult my 4000 Manual.

 

[amper42]

I also use a Denon AVR as a pre-pro (AVR-X4000).

Q: When you wrote "...turning off ALL...amps", do you mean a Setting to formally achieve that, or simply have no load(s) on any Outputs? I assume the latter, but it's been some years since my initial calibration and don't recall if "turning off" is a formal Setting. (I'm also assuming such firmware operation has not changed in Denon's designs spanning the two products in this discussiion (i.e., your 4700 and my 4000). Of course I could be wrong and may consult my 4000 Manual.

New to the Denon 3700, 4700, 6700 is the ability to select "Preout only" in amp assign. When this mode is set no signal is sent to the internal amps. This changes the Denon 4700 power handling to 46W for all functions. Of course, external amps are required to power your speakers with this configuration.

Earlier versions of Denon 3500, 3600, 4500, 6500 did not have this feature. In those models the internal amps can still induce distortion even when the preouts were used. I'm not familiar with the X4000.

 

[itz_all_about_the_music]

New to the Denon 3700, 4700, 6700 is the ability to select "Preout only" in amp assign. When this mode is set no signal is sent to the internal amps. This changes the Denon 4700 power handling to 46W for all functions. Of course, external amps are required to power your speakers with this configuration.

Earlier versions of Denon 3500, 3600, 4500, 6500 did not have this feature. In those models the internal amps can still induce distortion even when the preouts were used. I'm not familiar with the X4000.

Interesting. I'm investigating and am fairly confident by what I've read in the 4000 Manual and elsewhere, as well as the thermal state of the unit in operation, that there's more than 46W of dissipation at all times. But I shouldn't make assumptions based upon observed heat as 46W sustained is still a lot of BTUs.

Thanks.

 

[-Matt-]

There is an additional differentiator between the AVC-X3700H and the AVC-X4700H (I think not mentioned so far)...

From the 4700 up you get AL32 processing:

https://support-uk.denon.com/app/an...6/~/alpha-processing-and-what-types-are-there

When I was looking at AVRs the retailer made a big thing of this. Not sure if it really matters but having higher precision for internal processing certainly seems like a good idea.

 

[amper42]

Auro-3D with its Auro-Matic upmixer​

Denon AVR-X4700H supports Auro-3D and its Auro-Matic upmixer out of the box or after free firmware update. Auro-3D is an immersive 3D audio format developed by the Belgium-based company Auro Technologies. It consists of three layers of sound - surround, height and overhead ceiling. The base horizontal layer uses 5.1 or 7.1 format, the height layer is on top of the base layer and its information is extracted from the standard 5.1 surround PCM carrier. The a/v receiver decoder then extracts this information during playback. In home cinema Auro-3D comes with different listening formats - Auro 9.1, Auro 10.1 with added Top Ceiling channel ("Voice of God"), Auro 11.1 with added Front Height Center channel, and Auro 13.1 with added Left Rear Surround & Right Rear Surround channel. Auro-Matic upmixer takes non Auro-3D sound and upmixes to the current speaker configuration.

D.D.S.C.​

Denon AVR-X4700H has D.D.S.C (Dynamic Discrete Surround Circuit). A single IC chip is generally used in processing A/D, DSP, and D/A conversions that are vital to sound quality. The D.D.S.C. uses separate components to process the important sections of the A/D, DSP, and D/A conversions and therefore significantly improves signal processing capability and performance. In addition, the approach of developing and incorporating high-quality dedicated elements in the sections that configure the circuitry makes it easier to develop a high-grade, advanced surround circuit compared with the method where all processing is concentrated within a single chip. Denon’s proprietary digital audio technology that had for many years been developed for pure Hi-Fi components is now also alive in each block of the D.D.S.C

Advanced AL32 Processing​

Denon AVR-X4700H has Advanced AL32 Processing which uses a unique data interpolation algorithm to achieve high-bit, high-sampling output performance. The volume of information has been dramatically improved without any loss in the original data. The clean playback sound free of interference makes it possible to enjoy delicate details, accurate localization, and rich expression in the lower range. Advanced AL32 Processing has three functions: 1. High-bit up-conversion (Adaptive Line Pattern Harmonized Algorithm), 2. Advanced ALPHA Processing and 3. Adaptive digital filter (Automatic Low-Pass filter Harmonic Adjustment).

DO THESE FEATURES MAKE A DIFFERENCE?
1. I am unable to hear a difference Advanced AL32 provides. Maybe your ears are better or maybe it's marketing?
2. DDSC - again I can't align an audible sound improvement from this option. It alone wouldn't make the 4700 my only choice.
3. Auro 3D - if you have front and rear height speakers I would want the Denon 4700. I really like the Auro-3D option and it's definitely an audible difference. The other two (Advanced AL32 and DDSC) I could live without and probably never notice?

 

[Head_Unit]

The average power to surrounds is ridiculously low. Even with explosions and stuff

Yeah but what counts is the PEAK power. Clipping is clipping; even if surrounds usually have little energy on peaks they can be very loud. Just as loud, someboy who purported to do sound mixing once posted. I wish I knew what setup would generate that data.

@loque59 I'll jump on the "AVR is probably enough" bandwagon. And if it's NOT, that NAD is not enough to make much difference if any. You need like 3x300W @ 4Ω to start having really more power than an AVR, and that's usually expensive. I don't much believe in adding just a L/R amp because the center is just as loud or louder.

 

[Head_Unit]

ability to select "Preout only" in amp assign.

Ah, now if only you could turn off L/R, SL/SR, C etc selectably. Baby steps I guess.