Denon AVR-X4700 AVR Review (Updated)

[Fillius]

Are you able to take post Audyssey measurements in REW To verify what is going on? Maybe a center plus sub using moving microphone RTA measurement or an average of 4 -5 measurements of you listening position? It’s the only way I have found when something isn’t right.

Yes I should be able to, I've not used REW much so far, but I do have a UMIK-1. I was also planning to re-do the Audessey measurements and skip the last 2 positions behind the listening position in case it's too close to the back wall and throwing it off.

Are you running external a amplifier

No, all internal amps. I tried switching to pre-amp mode just to diagnose the sub, based on your success in your earlier post.

 

[Dj7675]

Using the app Sounds like? After you get an averaged measurement with REW, compare to what Audyssey measured. Make sure it is at least similar. If it the measurements aren’t similar that could be an issue in particular if doing full range eq. Audyssey is going to correct based on the measurement it gets... bad measurement will mean bad eq applied by Audyssey. If adding a boost on the low end (say +5 from 200 to 20), you need to add + to the sub level in order to get the crossover to match the mains. You may have already tried but if your speakers measure reasonably well,you might try correctly only 300, 500, or below 1K. I wouldn’t think anything would be wrong with Audyssey on the 6700 probably just need to do some measuring to see what is going on.

 

[peng]

Yes I should be able to, I've not used REW much so far, but I do have a UMIK-1. I was also planning to re-do the Audessey measurements and skip the last 2 positions behind the listening position in case it's too close to the back wall and throwing it off.

How about with Audyssey off, would the sub then come more alive?

It just seems so weird, I have had multiple D&Ms and never experienced the kind of issues you guys seem to be getting. When you said not getting much from the sub, did you mean compared to the AVR the 6700 replaced, if so what model was it?

 

[Fillius]

How about with Audyssey off, would the sub then come more alive?

It just seems so weird, I have had multiple D&Ms and never experienced the kind of issues you guys seem to be getting. When you said not getting much from the sub, did you mean compared to the AVR the 6700 replaced, if so what model was it?

I will try with Audessey off to see if the EQ is being over enthusiastic.

It replaced an Onkyo RZ730. The Onkyo had AccuEQ Advanced, but from my REW measurements, it didn't alter the sub much. The Onkyo set the sub level to -0.5dB with the subs gain in the same position, so it seems strange that I'm having to correct the Denon +10dB from measured to get similar results.

Using the app Sounds like? After you get an averaged measurement with REW, compare to what Audyssey measured. Make sure it is at least similar. If it the measurements aren’t similar that could be an issue in particular if doing full range eq. Audyssey is going to correct based on the measurement it gets... bad measurement will mean bad eq applied by Audyssey. If adding a boost on the low end (say +5 from 200 to 20), you need to add + to the sub level in order to get the crossover to match the mains. You may have already tried but if your speakers measure reasonably well,you might try correctly only 300, 500, or below 1K. I wouldn’t think anything would be wrong with Audyssey on the 6700 probably just need to do some measuring to see what is going on.

Yes I was using the MultiEQ app to add the boost to the curve. I tried viewing the file in Ratbuddyssey and all 8 positions were reasonable. I set the upper correction frequency to 800Hz which I think helped.

I'll take some REW measurements now.

 

[Castortroy3]

If it is awkward to have to adjust the subs so much than I have the same issue. This is my first D+M but I am adjusting the sub from -8.5 straight out of Audessey to 0 for movies and -2 for music (dynamic EQ off and used Radussey for a target curve).

Also in the manual test tone I barely hear the sub at all but they are definitely working.

 

[Castortroy3]

Not unfortunately.

No way it's good or turn around wouldn't take so much time. Great results will be rubber stamped. My fingers are crossed on the 3700 because I really don't want to have to return mine but I will. I'm using it right now but subjectively I'd say it is fine (no better or worse than the 2000 Yamaha I replaced (rxv2200) Will see what the tests say.

 

[studiocity]

I don't have one to confirm (3600 or 8500). But seeing how the marantz SR6104 had the same problem, it is likely that the issue exists in all Denon/Marantz products.

My Listening experience in case it helps, I Recently got the x6700h coming from a pioneer sc89, and I wasn’t happy with the denon’s musicality of the sound reproduction, but my dealer allowed me to upgrade to the 8500 and immediately I could easily hear an Improvement, Big one to me, which could be for several reasons and likely has zero to do with any problems with the 6700. But I can say the 6700 sounds fantastic on movies, non scientific of course, and sounds a bit “digital” on music, to me anyway. 8500 was immediately noticeably better for music and voices than the x6700 was, as soon as I turned it on. The up convert to 4K was also noticeably better in image quality on the 8500, It must have a different up converter chain than the 6700. I didnt need 8k so all is good. otherwise the 6700 was really great for the money.

 

[GXAlan]

Heat is a strange mandatory issue with current Denon/Marantz products.
During the last 40 year I used AVR from Marantz (when independent), Kenwood, Yamaha and none of them never got hot or needed a fan.
There is a design issue that needs to be raised by customers.

Also tricky since the more Class A bias you have the better things potentially sound and measure but the more Class A you have, the hotter it gets.

 

[LTig]

Also tricky since the more Class A bias you have the better things potentially sound and measure

This is not true. A class AB output stage has an optimal bias current. Stray from it in either direction and crossover distortion increases. See Souglas Selfs book about power amplifiers. There also was recent thread here about this.

 

[Fillius]

If it is awkward to have to adjust the subs so much than I have the same issue. This is my first D+M but I am adjusting the sub from -8.5 straight out of Audessey to 0 for movies and -2 for music (dynamic EQ off and used Radussey for a target curve).

Also in the manual test tone I barely hear the sub at all but they are definitely working.

After running some REW measurements I think I have found my issue.

There is a 15-20dB peak at 35Hz and a 10-15dB null at 60Hz and 80Hz. It's asking a bit much of Audessey to smooth out 35dB peak to peak.

The reason it seems quieter than with my Onkyo is probably because AccuEQ ignored the peak. Whereas Audessey is trying harder to workaround it by setting the level low and boosting the rest.

I'm going to try moving the sub within my limited space to see if I can find a decent compromise.

I'm still getting the mains hum in the left speaker at around 50Hz (mains frequency in the UK). The 4700 has similar transformer placement but the amplifier boards run perpendicular so it may not be as impacted if this is the cause.

 

[GXAlan]

This is not true. A class AB output stage has an optimal bias current. Stray from it in either direction and crossover distortion increases. See Souglas Selfs book about power amplifiers. There also was recent thread here about this.

Fair point, and haven’t seen this forum’s thread.

Douglas Self has demonstrated that optimal bias provides the best THD overall. Designs that overbias, allow you to have pure class A performance across the listening range with the consequence of transients having higher gm-doubling. Some low end designs may underbias to save money on heatsinks.

This product is nice in that it shows measurements for Blameless Class B against pure Class A
http://www.signaltransfer.freeuk.com/trimodal.htm

Optimal bias will determine w A transitions into B and you can do the math to get optimal numbers for the lowest overall THD.

 

[peng]

I'm still getting the mains hum in the left speaker at around 50Hz (mains frequency in the UK). The 4700 has similar transformer placement but the amplifier boards run perpendicular so it may not be as impacted if this is the cause.

One thing I can say about my Denons and Marantz is that they are near silent idling/standing by. I cannot say the same about even very expensive separates. So if you have an audible hum, and only the left channel, you should investigate, using a process of elimination as well to try and locate the root cause. If not, you really should request an exchange, as it is possible that your unit has a defect, probably in the grounding/shielding scheme. Your interconnect cables, and/or their layout/route may cause that too.

 

[peng]

Fair point, and haven’t seen this forum’s thread.

Douglas Self has demonstrated that optimal bias provides the best THD overall. Designs that overbias, allow you to have pure class A performance across the listening range with the consequence of transients having higher gm-doubling. Some low end designs may underbias to save money on heatsinks.

This product is nice in that it shows measurements for Blameless Class B against pure Class A
http://www.signaltransfer.freeuk.com/trimodal.htm

Optimal bias will determine w A transitions into B and you can do the math to get optimal numbers for the lowest overall THD.

I would think Denon/Marantz set their bias for optimal performance, not for class A at low output, well, may be the first 0.05 t 0.1 W at the most. However, I do think they are probably designed/set on the high side of optimal. I could be wrong as it just my hunch, seeing that comparable Yamaha units that are also class AB and have no visible better heat sinks would run notably cooler according to forum talks, that could also be unreliable. Anyway, it just a guessing game.. May be Amir can ask his contacts for comments on this perceived, and/or potential "hot" issue.

By the way, I don't know why there are so much talk about class AB implies a transition to B at some point, my understanding is that a real class AB amp is by definition class AB, that is, with bias optimally chosen so that both output devices in the push-pull cycles would conduct for a small angle of overlap in order to reduce crossover distortion. Wiki's definition seems to be among the clearest that I could find. That overlap angle is always there so again, it does not transit to class B as such. I suppose there could be amps advertised as class AB that actually transit to B in order to be more efficient, and run cooler. If so, I would avoid those amps.

As I cited earlier, if you compare the AVR-X3600H/X4700H's output graphs, you will see that they did very well at the low "first watt" range. Based on what I read from the Passlab website, my educated guess is that it might be an indication of class AB bias, while supposed to be "optimal", it might also be on the high side of optimal, resulting in a little less distortions at low level, but a little warmer even when idling or at very low output level.

 

[Fillius]

One thing I can say about my Denons and Marantz is that they are near silent idling/standing by. I cannot say the same about even very expensive separates. So if you have an audible hum, and only the left channel, you should investigate, using a process of elimination as well to try and locate the root cause. If not, you really should request an exchange, as it is possible that your unit has a defect, probably in the grounding/shielding scheme. Your interconnect cables, and/or their layout/route may cause that too.

All other speakers are silent, including the sub. The noise doesn't increase or decrease when changing the volume.

I had my front speakers configured as bi-amped first, I swapped the high/low wires, no improvement. I switched to single amp mode, no improvement.

I will try disconnecting all input devices one by one. The fact it is only in the left speaker could imply an issue with the analogue input from my Topping D50s DAC, although the hum is present on all sources. All other input devices are HDMI.

Has anyone else noticed this on their X6700 or X4700? I can see no indication of this in any of the X4700 measurements. So unless it's specific to the X6700, I may have a faulty unit.

 

[peng]

All other speakers are silent, including the sub. The noise doesn't increase or decrease when changing the volume.

I had my front speakers configured as bi-amped first, I swapped the high/low wires, no improvement. I switched to single amp mode, no improvement.

I will try disconnecting all input devices one by one. The fact it is only in the left speaker could imply an issue with the analogue input from my Topping D50s DAC, although the hum is present on all sources. All other input devices are HDMI.

Has anyone else noticed this on their X6700 or X4700? I can see no indication of this in any of the X4700 measurements. So unless it's specific to the X6700, I may have a faulty unit.

I know it is not the speakers, but if it is grounding and/or interference related issues then you have to eliminate the interconnect cabling related possibilities too. Hopefully it is actually because then you don't have to send the unit back.

 

[MJNOLES1]

Thanks. I did do the firmware update. I had the 4500 something went wrong with it and I was able to upgrade to 6700 for the difference in price. I was also on the fence about the price difference from the 4700 to the 6700 but 6700 was made in Japan so I figured it was that much better.

What is your personal opinion of the x4500 vs x6700? In regard to sound quality of movies, tv viewing, and music?

 

[MJNOLES1]

My Listening experience in case it helps, I Recently got the x6700h coming from a pioneer sc89, and I wasn’t happy with the denon’s musicality of the sound reproduction, but my dealer allowed me to upgrade to the 8500 and immediately I could easily hear an Improvement, Big one to me, which could be for several reasons and likely has zero to do with any problems with the 6700. But I can say the 6700 sounds fantastic on movies, non scientific of course, and sounds a bit “digital” on music, to me anyway. 8500 was immediately noticeably better for music and voices than the x6700 was, as soon as I turned it on. The up convert to 4K was also noticeably better in image quality on the 8500, It must have a different up converter chain than the 6700. I didnt need 8k so all is good. otherwise the 6700 was really great for the money.

I wonder if the Denon x4500, that I just bought, will have the same musicality benefits as the 8500? I know the 8500 is a few steps above mine but still the same model year family, compared to the newer x6700.

 

[KC-Narnia]

All other speakers are silent, including the sub. The noise doesn't increase or decrease when changing the volume.

I had my front speakers configured as bi-amped first, I swapped the high/low wires, no improvement. I switched to single amp mode, no improvement.

I will try disconnecting all input devices one by one. The fact it is only in the left speaker could imply an issue with the analogue input from my Topping D50s DAC, although the hum is present on all sources. All other input devices are HDMI.

Has anyone else noticed this on their X6700 or X4700? I can see no indication of this in any of the X4700 measurements. So unless it's specific to the X6700, I may have a faulty unit.

I have not experienced anything like that on my AVR-X6700H. I hope you find a solution to the problem.

 

[zelig]

Here is my pitch for a new Netflix comedy series. Let me know what you think.

The IEEE Crowd - The misadventures of a team of engineers working for a multinational electronics company.

Episode One - The Engineering Call

• Jen: Hey guys, some bad news. Amir at AVS has reviewed the 67000 and sent over his results; they're not good.
• Roy: Awww for f#*k's sake! Not that guy AGAIN! I'm still recovering from 3 days straight with him in the 47000 fiasco. My doctor says I need to rest.
• Jen: Yeah, I feel for you Roy, but we gotta deal with this one way or another. Sales will drop thru the floor if we don't get in front of this.
• Roy: Can't we just slip him a few bucks, like we do for the other reviewers?
• Jen: Sadly no. The guy appears to be inscrutable. Besides, looking at photos of his listening room I'd say he probably has more money than Bill Gates.
• Roy: F%^k! OK, how about deny, deny deny? We'll publish our (nicely curated) measurements to counter his narrative and claim his measurements are bogus. That worked last time, didn't it? We can slip that guy over at the AudioAddicts forums a few more bucks to back us up and spank AVS.
• Jen: Shit no! That backfired last time. People thought we tried to bury the issue, and as for the AudioAddicts guy... that was a waste of $10. He just came off like a pompous twat and did our case more harm than good.
• Roy: So maybe we put out a post saying that we are aware of the issues and a firmware fix will be out some time "soon". Customers are suckers for firmware updates - they love them, even when the only change is the version number! Heh heh! (Wink!)
• Jen: That may work for about 2 minutes, but we still owe them a firmware update for the 47000 and they won't forget that. There's that thread over at AVS that just won't die!
• Roy: Shit, shit, and thrice shit! What to do?!

To be continued... (maybe, if you click "Like")

 

[chaking]

well played zimberto - just one addition - probably should have started off with, "did he turn it off and back on again?"