Denon AVR-X3600H AV Receiver Review

[A.West]

So I've read through the review, and all the comments here. Being a bit new to all of this, I have a question. I understand that the receiver measured very well when connected to a set of external power amps and the 11.2 trick is done to decouple the pre from the power amps for the front channels.

But how does it measure when used as a standalone pre and power amp for, say a 5.1, setup? With no external amplification. If it clips at 1.5V from the pre, how loud can you go (SPL) on a set of fairly sensitive speakers (say 89dB) before you get any measurable distortion of any significance?

Short answer: with 90db 4 ohm speakers, the pre outs should deliver over 103db to your seated position before going into higher distortion mode, assuming no other limitations in your chain. That's very loud, so not a practical concern for me. Long answer below.

March Audio above suggests a normal sensitivity external amp could send over 200w before pre-outs go into higher distortion mode. Using some db math i found online, that would equal about 113dB with 90dB sensitivity speakers. (At one meter away) The pre outs would drop down in performance to use the 225w to 450w zone that could conceivably drive speakers up to 116db. However 2 to 3 meters away, spl would be 6 to 10 db lower,.
I think volume that loud would be unpleasant and dangerous, and hopefully brief, like an explosion in an action movie, or a brief symphonic climax. So as long as we are using speakers with at least moderate sensitivity (86db) this pre-out distortion zone is likely to be masked by the higher distortion of speakers pushed to their limits, and the overloading of our ears. (I wear earplugs at live rock concerts because my own ears get "oversaturated" beyond probably 100db, and don't want to lose my hearing longer term either). Prolonged listening above 90db will damage your hearing.

 

[peng]

One thing also to note with Denon / Marantz in regards to power is there “70% guarantee” which guarantees 70% of the rated 2 channel output into 5 channels.

The guarantee is for the 8 ohm nominal impedance load spec only. Denon did not rate their AVRs for 4 ohms without using the impedance setting that limits the rail voltage, though we all know it can handle 4 ohms while keeping the default 8 ohm setting if use properly/accordingly.

 

[peng]

It would be interesting if amps could be safely disconnected and use as a preamp. Find the cheapest 11 channel AVR, disconnect the amps and you have something that outperforms the AV7705 and AV8805 for example.

So far we have seen the AV7705 measured not as good as the X3600H, but before I would agree with you I would like to see one more, preferable a SR6012/13/15 or SR7012/13. We have already seen the SR8012 measured by AH, so I think I am just trying to take the "abundance of caution" approach before concluding Denon outperform Marantz in DAC/pre-outs SINAD. The thing is, if true, one would have to choose between the subjective based/claimed benefits of HDAM and the objective based/measurable benefits of not having the HDAM. Also, in practical terms, it could all be anecdotal and moot. Still will be fun if we can figure that all out.

 

[Dj7675]

So I've read through the review, and all the comments here. Being a bit new to all of this, I have a question. I understand that the receiver measured very well when connected to a set of external power amps and the 11.2 trick is done to decouple the pre from the power amps for the front channels.

But how does it measure when used as a standalone pre and power amp for, say a 5.1, setup? With no external amplification. If it clips at 1.5V from the pre, how loud can you go (SPL) on a set of fairly sensitive speakers (say 89dB) before you get any measurable distortion of any significance?

While it may not be exact, I would refer to the x3500h review @amirm did not too long ago. LINK If I am understanding it correction you are looking at a SINAD of 96 for the DAC as long as you keep your volume below 80. I believe you get the same performance as long as you keep it below 1.5V on the preouts. For example I believe the outlaw 5000 amp you can drive fully keeping output below 1.5.
In my opinion (both x3500h/x3600h), this is actually very good performance for what it does and in the case of the x3500h can be had for around $500. Both are good ht receivers at their price points. I will let smarter people than me explain SPL...

 

[peng]

Are there any other requests left?

Can you be clear (sorry if I missed something you said already..) that if ECO is 'ON", it will still de-grade DAC/pre-outs SINAD even with the amps disconnected? I mean the front left and right channels obviously as only those can be disconnected.

Other than that I am curious why you are willing to do so much measurements on this little 28 lbs AVR? That has got to be a record, in terms of the scope of measurements on any electronic gear by you so far. Not complaining, and really appreciate it knowing how busy you are. And I wish everyone will up their donation. I will as soon as the C$ improve a little...but won't wait long regardless.

 

[peng]

If it clips at 1.5V from the pre, how loud can you go (SPL) on a set of fairly sensitive speakers (say 89dB) before you get any measurable distortion of any significance?

I think we are getting into this chicken and egg thing? The findings so far seem to indicate the pre-outs SINAD would drop from about 100 dB to 74 dB or less at volume position near "0" in the relative scale, but the cause appeared to be the power amp clipping, not the preamp. That is, power amp would clip (yes, with no speakers connected) and would spill dirt in a way that cause the SINAD of the pre-outs being measured to drop. So when you said ......it clips at 1.5V from the pre......., did you imply the "pre" was the culprit?

 

[Dj7675]

I think we are getting into this chicken and egg thing? The findings so far seem to indicate the pre-outs SINAD would drop from about 100 dB to 74 dB or less at volume position near "0" in the relative scale, but the cause appeared to be the power amp clipping, not the preamp. That is, power amp would clip (yes, with no speakers connected) and would spill dirt in a way that cause the SINAD of the pre-outs being measured to drop. So when you said ......it clips at 1.5V from the pre......., did you imply the "pre" was the culprit?

Where is the 74 number coming from, the X3500H test? If so that was at 2V. It is well behaved at 1.5V and under @ a SINAD of 96. At least that was my take away from the review. Please do correct me if I'm wrong about that as I think it is important. See post 10 LINK

 

[peng]

Where is the 74 number coming from, the X3500H test? If so that was at 2V. It is well behaved at 1.5V and under @ a SINAD of 96. At least that was my take away from the review. Please do correct me if I'm wrong about that as I think it is important. See post 10 LINK

I thought Sagnet referred to the 3600, that was about 74 at 2 V without the amp disconnect trick so I made a safe assumption that it would be 74 at 1.5 V as well as that would be the worst case scenario.

If you want to talk about the X3500H, Amir did not say anything about SINAD at 1.5 V for the X3400H but he said "1.2 volt is essentially the same. It goes crazy after 1.5 volt (vol = 80). Based on that, we know up to 1.2 V it was a little better than 95 dB and it went crazy "after" 1.5 V. So we don't know what it would be between 1.2 and 1.5 V, but it is reasonably safe to assume the 3500 should get within a couple dB from the 3600's because it has the same DAC and volume control that direct affects the measurements in question.

 

[Dj7675]

I thought Sagnet referred to the 3600, that was about 74 at 2 V without the amp disconnect trick so I made a safe assumption that it would be 74 at 1.5 V as well as that would be the worst case scenario.

If you want to talk about the X3500H, Amir did not say anything about SINAD at 1.5 V for the X3400H but he said "1.2 volt is essentially the same. It goes crazy after 1.5 volt (vol = 80). Based on that, we know up to 1.2 V it was a little better than 95 dB and it went crazy "after" 1.5 V. So we don't know what it would be between 1.2 and 1.5 V, but it is reasonably safe to assume the 3500 should get within a couple dB from the 3600's because it has the same DAC and volume control that direct affects the measurements in question.

I read again and you are correct about it being a SINAD of 96 or so at 1.2V. We also know as you pointed out that it is a SINAD of 74 @ 2V. We don’t know what it is at 1.5V, just that @amirm noted it goes crazy above 1.5V but we don’t really know what it does at 1.5V unless Amir recalls. Probably doesn’t matter too much but it is important not to match it with an amp that requires more than 1.5v for sure. Main takeaway is both x3500h and 3600h perform pretty well within these limits.

 

[Bear123]

A good option to put forth for folks combining an external amp with the Denon X3500H(or 3400/3300) might be the Monoprice Monolith 2/3/5/7 channel amp. It runs around $13-$1700, seems to measure well, has enough power for most speakers, and produces full power with 1.43 volts. This would seem to keep it down in the cleaner operating range of the pre-3600 Denon's. It would be nice to know what voltage signal these AVR's are outputting at reference level. The information I've seen is using the somewhat meaningless volume levels of "79.5" or "82". I have no idea what that means. Volumes should be set to reference level in order to give meaning and context to the number. Does "79" mean 5 above reference? 10 below reference? This would be helpful for not only Denon products, but for folks using any brand of AVR that may want to upgrade to the Denon in order to get Audyssey XT32, the phone app, the excellent Sub Eq HT, and the relatively good amp and pre-out performance. If the loudest they ever listen is -5 MV on their Pioneer or Yamaha, and the Denon 3500 puts out 1.5 volts at -5 MV, then we know they will get a very clean signal to whatever amp they may want to use, and also help to make sure the amp they select can be fully driven.

 

[Sagnet]

I think we are getting into this chicken and egg thing? The findings so far seem to indicate the pre-outs SINAD would drop from about 100 dB to 74 dB or less at volume position near "0" in the relative scale, but the cause appeared to be the power amp clipping, not the preamp. That is, power amp would clip (yes, with no speakers connected) and would spill dirt in a way that cause the SINAD of the pre-outs being measured to drop. So when you said ......it clips at 1.5V from the pre......., did you imply the "pre" was the culprit?

I was thinking about this paragraph from the opening post: "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."

 

[Dj7675]

A good option to put forth for folks combining an external amp with the Denon X3500H(or 3400/3300) might be the Monoprice Monolith 2/3/5/7 channel amp. It runs around $13-$1700, seems to measure well, has enough power for most speakers, and produces full power with 1.43 volts. This would seem to keep it down in the cleaner operating range of the pre-3600 Denon's. It would be nice to know what voltage signal these AVR's are outputting at reference level. The information I've seen is using the somewhat meaningless volume levels of "79.5" or "82". I have no idea what that means. Volumes should be set to reference level in order to give meaning an context to the number. Does "79" mean 5 above reference? 10 below reference?

I believe 80 is reference level, 70 is -10. Those Monolith amps do appear to be great performers and reasonably priced. But the 7 channel weighs 93lbs... wow.

 

[MarcT]

So, rookie question here. Relative to all this, I see that my power amp specs indicate an input impedance of 100 kOhms and input sensitivity of 2.71 Vrms. What are the implication of those specifications for use with these Denon AVRs? I currently use my AVR-X5200 for the front L/R channels, but it is getting long in the tooth and I don't know how its SINAD scores would compare to the 3600 or even the newer 4xxx or 6xxxx AVR series.

 

[amirm]

So, rookie question here. Relative to all this, I see that my power amp specs indicate an input impedance of 100 kOhms and input sensitivity of 2.71 Vrms. What are the implication of those specifications for use with these Denon AVRs?

The impedance doesn't matter. The 2.71 volt does and says to get to max power, you need that much output voltage from AVR Pre-outs. Refer to this measurement:

Horizontal scale ends at 3 volts out of the pre-out. So you lose a bit of performance when you to up to 2.7 volt but not that significant.

 

[Sagnet]

Are there any other requests left?

It would be interesting to see how this thing measures with Eco Mode set to "Auto". That's what's recommended by Audioholics, is arguably the most commonly used setting.

 

[BsdKurt]

... to the 3600 or even the newer 4xxx or 6xxxx AVR series.

Just wanted point out the x3600h is a 2019 model and the x4500 and up are 2018 models. Denon seems to be moving to an every other year upgrade cadence. The updates to x4500h and up were planned for 2020 (pre covid). I guess Denon figured out we were all buying last year's models and probably killing their profits in the process.

The Denon 2019-2020 Range & Technology Update has some pretty good info on what's coming.

 

[MarcT]

The impedance doesn't matter. The 2.71 volt does and says to get to max power, you need that much output voltage from AVR Pre-outs. Refer to this measurement:

Horizontal scale ends at 3 volts out of the pre-out. So you lose a bit of performance when you to up to 2.7 volt but not that significant.

Thanks! So, with respect to my 5200, Gene over at AH tested a 5200 and said:

"I measured unclipped output of 4.5Vrms from every channel. We like to see at least 2Vrms and the Denon met this with over 6db of margin to spare."

If I understand everything correctly, that would indicate that even if the 5200 output got up to 2.71 volt, it would still just be a little over its max output of 4.7 volt. But he doesn't say anything about what sort of SINAD score that would translate into. I'm wondering what sort of SINAD score the 5200 could achieve.

https://www.audioholics.com/av-receiver-reviews/denon-avr-x5200w/measurements

 

[BsdKurt]

The impedance doesn't matter. The 2.71 volt does and says to get to max power, you need that much output voltage from AVR Pre-outs. Refer to this measurement:

Between your explanation here and @March Audio previous one, I understand that an amplifier that has an input sensitivity greater than what's being output by the pre-outs will not reach its max power. However, I've been scratching my head wondering what would happen when paired with an amplifier with a 1 volt input sensitivity such as the Parasound HALO amps? Say you put an A 21+ on L/R with internal amps disconnected and you're listening to a mutli-channel source. Wouldn't the L/R channels increase in volume more than the internal amps as you turned up the volume?

 

[SoundofMuzak]

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:

View attachment 59144​

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:

View attachment 59145​

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:

View attachment 59146

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:

View attachment 59147

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:

View attachment 59148

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:

View attachment 59149

Dynamic range was better than I expected:

View attachment 59150

32-tone test which is at less than full digital level shows the better performance of the DAC yet again in that situation:

View attachment 59151

Linearity was also surprisingly good:

View attachment 59152

Intermodulation test showed the advantage of low noise floor (for an AVR):
View attachment 59153

Jitter test showed some issues though over coax input:
View attachment 59160

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:

View attachment 59154

This is well above average for some 85 amplifiers I have tested so far:
View attachment 59156

And the best among AVRs but with small margin of victory:

View attachment 59155

Frequency response in all three modes was wide showing no digitization at low sample rate:
View attachment 59157

Crosstalk was fine:
View attachment 59158

Signal to noise ratio was very good, clearing the CD/16-bit hurdle of 96 dB at just 5 watts:

View attachment 59159

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:

View attachment 59161

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:
View attachment 59162

Switching to 8 ohm we get:

View attachment 59163

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:

View attachment 59165

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/

The Denon AVR-X3600 has a pretty stellar review as compared to its predecessor the Denon AVR-X3500H which had a NOT SO stellar review. Why such an improvement from one model year to the next? It is a shame because you can get the 2018 3500 model for less than half price right now. Thank.

 

[amirm]

Between your explanation here and @March Audio previous one, I understand that an amplifier that has an input sensitivity greater than what's being output by the pre-outs will not reach its max power. However, I've been scratching my head wondering what would happen when paired with an amplifier with a 1 volt input sensitivity such as the Parasound HALO amps? Say you put an A 21+ on L/R with internal amps disconnected and you're listening to a mutli-channel source. Wouldn't the L/R channels increase in volume more than the internal amps as you turned up the volume?

As soon as you use an external amp, you need to adjust the levels for those to match the internal amplifier gains. Audyssey will do that automatically for you.