This is a review and detailed measurements of the Denon AVR-X3600H 9.2 channel AVR. It was purchased new by a kind member who drop shipped it to me. It costs US $1,099.
From outside the AVR-X3600H seems like any other AVR:
But the controls feel a lot better than some other AVRs. The volume control rotary encoder has the right stiffness and feels good to manipulate.
The back panel has the usual connectivity including some useless ones such as component video:
But there is one thing that is special about this AVR: if you set it to 11 channel mode which is more than the number of amplifier channels it has, it lets you disconnect the internal amplifier and route that to pre-out. This means that you don't have to deal with that amplifier clipping and reducing DAC performance when you use an external amplifier. This has been the weakness of most AVRs I have tested. We will see later if it works in measurements.
A downer is the low resolution of the on-screen user interface. I think it is SD resolution. Not a big deal in practice but in this day and age it should at least be 1080p.
For this testing, I only used the coax input for digital source. If I have time later, I will also test HDMI. I don't think it impacts anything but jitter performance.
One other nice thing about this AVR: it has a "real" extruded aluminum for the amplifier heatsink. Most AVRs have these flimsy spring iron with no mass and hence high thermal impedance. It got the hottest in the middle which fortunately is where there is a fan underneath. Even though the amp got quite warm after my testing, I was surprised the fan had not come on. So I suggest giving it plenty of ventilation.
AVR DAC Audio Measurements
As usual we start by evaluating the Digital to Analog Converter by feeding the AVR a 1 kHz tone using Coax input and measuring what comes out of pre-out. At first I tested it in normal mode and it could only go up to 1.5 volt before the amp clipped and sunk the DAC performance with it. When I enabled the 11 channel mode and redirected the amp from left and right channel, that problem completely vanished:
When I first ran this test, I had set the sample rate to 48 kHz by accident and SINAD, for the first time in any video product, went up to 103 dB! Sadly and for unknown reason, setting it to 44.1 kHz increased second harmonic causing SINAD to drop to 99 dB. Still excellent though for an AVR:
But oh so close in beating all dedicated high-end home theater processors! Amazing what a little analog switch and trivial software allows.
I wanted to show what the SINAD would be relative to output level but the curve there was highly dependent on the volume setting. I picked a random, 85 on the volume indicator and got this:
Notice that even with 44.1 kHz we get a SINAD of 103 dB. The reason that is higher than the dashboard is because the digital input is lower value in this test than full 0 dB used in the dashboard.
Notice slightly better performance for 48 kHz as I indicated (in red). Since majority of video content is produced at 48 kHz and multiples of it, that is not a bad thing although you could argue when you want the best performance, it would be for music content. Either way, strange to see the output of the DAC be better at 48 kHz. I wonder if some format conversion is occurring internally for 44.1 kHz. Test of the filtering did NOT show this as the output seems to be different for 44.1 versus 48:
Dynamic range was better than I expected:
32-tone test which is at less than full digital level shows the better performance of the DAC yet again in that situation:
Linearity was also surprisingly good:
Intermodulation test showed the advantage of low noise floor (for an AVR):
Jitter test showed some issues though over coax input:
By the way, I played with Direct and Pure Direct modes and it made no difference in any of the above tests. The same was true of the amplifier tests below.
AVR Amplifier Measurements
Let's start with our amplifier dashboard of 5 watts:
This is well above average for some 85 amplifiers I have tested so far:
And the best among AVRs but with small margin of victory:
Frequency response in all three modes was wide showing no digitization at low sample rate:
Crosstalk was fine:
Signal to noise ratio was very good, clearing the CD/16-bit hurdle of 96 dB at just 5 watts:
AVR Amplifier Power Measurements
Let's start with our 4 ohm load and see how much power we get before distortion goes through the roof:
Notice how much lower noise and distortion are compared to the NAD. The amp is not "rated" for 4 ohm by the way due to legalize (keeping the amp from getting too hot during safety testing). But works absolutely fine. To wit, you can push it even harder if you allow higher distortion level or allow burst of power:
Switching to 8 ohm we get:
Specification is 105 watts at 0.08% distortion and we are there already at much lower distortion.
Testing power capability and sensitivity to frequency we get very predictable performance:
You loose a bit of power at 20 Hz and distortion does rise fair bit at 20 kHz but still, I take this over some amplifiers with curves that go all over the place.
Importantly the amplifier did not shut down or complain one bit during this test which pushes the unit to clipping some 7 times with both channels driven.
Conclusions
People think we are hard to please when testing AVRs but we really are not. We like to see the unit properly tested and verified to perform well and the Denon AVR-X3600 gets there with ease. It is clear proper testing was involved even though the "bones" of this AVR may have come from the rest of the corporate parts bin. While I like to see a simple option in the UI that disables the amps from mains, the kludge that is there with 11 channel mode is workable.
Desktop audio products still have nothing to fear from AVRs when it comes to absolute transparency and superb performance. But the Denon gets you a combination of audio/video system with room EQ which enables scenarios they cannot serve.
Overall, I am pleased to put the Denon AVR-X3600H on my recommended list. It is the best of a bunch by a good margin.
The only thing that may be a concern is the Audyssey Room EQ. My past experience with Audyssey has not been very positive relative to more advances systems (Dirac, Anthem ARC). If I have time, I might test it in this incarnation to see where it lands.
-----------
As always, questions, comments, recommendations, etc. are welcome.
My bandwidth usage on my server is reaching the limit despite using caching. So pretty soon I may need to upgrade. I know, $5/month for extra bandwidth may not be a lot to you but it is a huge problem for me! I can't stand losing a penny more from my bank account. So please donate what you can using : https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
From outside the AVR-X3600H seems like any other AVR:
But the controls feel a lot better than some other AVRs. The volume control rotary encoder has the right stiffness and feels good to manipulate.
The back panel has the usual connectivity including some useless ones such as component video:
But there is one thing that is special about this AVR: if you set it to 11 channel mode which is more than the number of amplifier channels it has, it lets you disconnect the internal amplifier and route that to pre-out. This means that you don't have to deal with that amplifier clipping and reducing DAC performance when you use an external amplifier. This has been the weakness of most AVRs I have tested. We will see later if it works in measurements.
A downer is the low resolution of the on-screen user interface. I think it is SD resolution. Not a big deal in practice but in this day and age it should at least be 1080p.
For this testing, I only used the coax input for digital source. If I have time later, I will also test HDMI. I don't think it impacts anything but jitter performance.
One other nice thing about this AVR: it has a "real" extruded aluminum for the amplifier heatsink. Most AVRs have these flimsy spring iron with no mass and hence high thermal impedance. It got the hottest in the middle which fortunately is where there is a fan underneath. Even though the amp got quite warm after my testing, I was surprised the fan had not come on. So I suggest giving it plenty of ventilation.
AVR DAC Audio Measurements
As usual we start by evaluating the Digital to Analog Converter by feeding the AVR a 1 kHz tone using Coax input and measuring what comes out of pre-out. At first I tested it in normal mode and it could only go up to 1.5 volt before the amp clipped and sunk the DAC performance with it. When I enabled the 11 channel mode and redirected the amp from left and right channel, that problem completely vanished:
When I first ran this test, I had set the sample rate to 48 kHz by accident and SINAD, for the first time in any video product, went up to 103 dB! Sadly and for unknown reason, setting it to 44.1 kHz increased second harmonic causing SINAD to drop to 99 dB. Still excellent though for an AVR:
But oh so close in beating all dedicated high-end home theater processors! Amazing what a little analog switch and trivial software allows.
I wanted to show what the SINAD would be relative to output level but the curve there was highly dependent on the volume setting. I picked a random, 85 on the volume indicator and got this:
Notice that even with 44.1 kHz we get a SINAD of 103 dB. The reason that is higher than the dashboard is because the digital input is lower value in this test than full 0 dB used in the dashboard.
Notice slightly better performance for 48 kHz as I indicated (in red). Since majority of video content is produced at 48 kHz and multiples of it, that is not a bad thing although you could argue when you want the best performance, it would be for music content. Either way, strange to see the output of the DAC be better at 48 kHz. I wonder if some format conversion is occurring internally for 44.1 kHz. Test of the filtering did NOT show this as the output seems to be different for 44.1 versus 48:
Dynamic range was better than I expected:
32-tone test which is at less than full digital level shows the better performance of the DAC yet again in that situation:
Linearity was also surprisingly good:
Intermodulation test showed the advantage of low noise floor (for an AVR):
Jitter test showed some issues though over coax input:
By the way, I played with Direct and Pure Direct modes and it made no difference in any of the above tests. The same was true of the amplifier tests below.
AVR Amplifier Measurements
Let's start with our amplifier dashboard of 5 watts:
This is well above average for some 85 amplifiers I have tested so far:
And the best among AVRs but with small margin of victory:
Frequency response in all three modes was wide showing no digitization at low sample rate:
Crosstalk was fine:
Signal to noise ratio was very good, clearing the CD/16-bit hurdle of 96 dB at just 5 watts:
AVR Amplifier Power Measurements
Let's start with our 4 ohm load and see how much power we get before distortion goes through the roof:
Notice how much lower noise and distortion are compared to the NAD. The amp is not "rated" for 4 ohm by the way due to legalize (keeping the amp from getting too hot during safety testing). But works absolutely fine. To wit, you can push it even harder if you allow higher distortion level or allow burst of power:
Switching to 8 ohm we get:
Specification is 105 watts at 0.08% distortion and we are there already at much lower distortion.
Testing power capability and sensitivity to frequency we get very predictable performance:
You loose a bit of power at 20 Hz and distortion does rise fair bit at 20 kHz but still, I take this over some amplifiers with curves that go all over the place.
Importantly the amplifier did not shut down or complain one bit during this test which pushes the unit to clipping some 7 times with both channels driven.
Conclusions
People think we are hard to please when testing AVRs but we really are not. We like to see the unit properly tested and verified to perform well and the Denon AVR-X3600 gets there with ease. It is clear proper testing was involved even though the "bones" of this AVR may have come from the rest of the corporate parts bin. While I like to see a simple option in the UI that disables the amps from mains, the kludge that is there with 11 channel mode is workable.
Desktop audio products still have nothing to fear from AVRs when it comes to absolute transparency and superb performance. But the Denon gets you a combination of audio/video system with room EQ which enables scenarios they cannot serve.
Overall, I am pleased to put the Denon AVR-X3600H on my recommended list. It is the best of a bunch by a good margin.
The only thing that may be a concern is the Audyssey Room EQ. My past experience with Audyssey has not been very positive relative to more advances systems (Dirac, Anthem ARC). If I have time, I might test it in this incarnation to see where it lands.
-----------
As always, questions, comments, recommendations, etc. are welcome.
My bandwidth usage on my server is reaching the limit despite using caching. So pretty soon I may need to upgrade. I know, $5/month for extra bandwidth may not be a lot to you but it is a huge problem for me! I can't stand losing a penny more from my bank account. So please donate what you can using : https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
