x 4700h also has Auro 3D, which I’m actually preferring for upmixed stereo t.v. (news, talk shows).
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Denon AVR-X6700H Home Theater AVR Review
- Thread starter amirm
- Start date
Are your discussing the X6700H, or any of the higher-end Denon units? What is your source for this information? Your information isn't correct.
- It's a bit of a waste of time to have to enter all this information, but it does give an idea of the complexity of the power supplies in these units based on the X6500H. .
The power transformer has multiple windings:
o One set of windings go to the power amplifiers via a typical linear power supply with diode rectifier circuits and electrolytic capacitors
o One set of windings are for a +/- 7V supply for uses such the opamps, volume control, small signal switches. A diode rectifier circuit and IC voltage regulators are the key components here. A 5V regulator is connected to this supply for the tuner.
o One set of windings are for the fans, relays and triggers. This 12V supply includes a diode rectifier circuit and a DC to DC converter.
o One set of windings are for the DAC 5V and 3.3V supplies. User diode rectifier circuits and two IC voltage regulators.
An finally,
o Two sets of windings are for the display. One set directly supplies AC to an IC for the display. The other set supplies a simple 1/2 wave regulator.
Depending on the characteristics of these display power circuits it is possible that variations in the power amplifier outputs could affect display. Alternatively cable routing in some units could cause currents in the power amplifier supply to induce currents in the display power circuitry.
The 5.2V output of the SMPS supplies numerous (a dozen or more) secondary power supplies, which are typically DC-DC converters, for digital components.
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Gosh, I thought I had post my thermal measurements but had forgotten! I just added them to the review:
This AVR is definitely cooking.
AVR Protection from Excessive Temperatures
In the similar X6500H the cooling fans are activated according to the following heatsink temperatures.
95C - Fans operate on High Speed
90C - Fans operate on Medium Speed
78C - Fans operate on Low Speed
125C - shutdown
100C - Change to lower rail voltage for power amplifier channels - effectually ECO Mode
Looks like these units are designed to run at what seem like high temperatures to humans. Of course these are the heatsinks and power transistors, both of which won't have problems at these temperatures.
The heatsinks are silver colored so they will have low thermal emissivity, and shouldn't radiate too much heat into surrounding components. Most cooling would be by passive convection, or active if the fans are operating, with the majority of the heat going up and out of the case. Clearly putting these units in a confined space means external fans would be a good idea.
It was mostly an educated guess, thanks for the clarification! I've edited my original post to include a link to your explanation. Since the SMPS is quite beefy my guess was that it would be used for everything except the power amps. Looks like I was wrong. Let's see what that brings us then:
There is another reason the display can sag under load: once the core of the transformer is saturated, voltage on all windings will drop as well. For the regulated windings that is mostly not an issue, for unregulated windings it can have side effects.
Which brings us to the next one:
Actually these specs are kind of regulated, however for some reason they don't need to tell you the exact measurement technique. In the video below it actually give a bit of info: 1/8 max power white noise, all channels driven. That's about 25W per channel. Man, that's one hot amplifier! Looking at the beefy SMPS I bet the digital parts eat quite a lot of power (and heat) as well.
Yippy, an actual (double) full bridge rectifier
But yes, the power supply system can always deliver some more than the transformer rating.. It specifically says for "short time" (whatever that means). Also don't forget that music (or movie audio) has quite a high crest factor, making it possible to actually use the additional potential locked away in those power supplies. Based on these numbers my guess would be that you have about 150W of average music power per channel if all are driven. Like I said before: these things will still make a hell of a noise (and heat). I would not really worry about it to much in any case. 150W or 200W is only 1.14dB of difference anyway. To have an amp actually sound twice as loud to humans, you need 10 times the power (and probably new speakers ).Anyway: we should probably donate to Amir for a 13 channel speaker load so he can actually perform these kinds of tests
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Thank you very much for the info. I wish they would include such useful information on their website instead of relying on a You-tube video. Anyway, 2.8 kVA is of course 2,800 VA (your kwa must be a typo, there is no such term) but VA - W only if the power factor is 1, that is when the phase angle between the voltage and current is 0 degree, so in the load is a resistor then 2800 VA is in fact 2800 W, obviously for loudspeaker loads but that's okay as long as we compare apples to apples when comparing its transformer rating with other models.
If they were still referring to "consumption", not the transformer's actual VA rating, then it means it was the VA drawn from the outlet. In that case, the actual amp output would be much less, depending on the unit's overall efficiency and for class AB amp, that can be somewhere between about 50 to 75%, typically higher, that is closer to 70% at near rated output.
Yes there are standards, my point was about whether all manufacturers follow the same one. Based on the specified "power consumption" figures of various models/brands, I highly doubt that they did. Over the years, Denon has switched the way they specified it too, from VA, to A (amperes), to now W, all over the map..., and then the add confusion of Yamaha's "max" vs the non max, but the max has been for the more recent models only and iirc, the "max" was sometimes qualified with a distortion number such as 10%, so it is not the average vs max thing because if it is then the factor would have been exactly 2, i.e. 500 W avg, would be 1000 W peak (max?). Anyway, I do wish it is regulated, then they all have to follow the same rule.
Yeah.. where are the good old PMPO days.. 
At 2-3x the price it should eat it raw
In case you did serious/extensive comparisons, some additional sound impressions might be useful.
2.8 kW is the rating of the Transformer, so the actual output depends how much the digital components draw and how good the Class AB efficiency on the unit is.
I think you can substract about 80W max for the digital stuff which leaves you about 1.9 kW with estimated 70% efficiency.
But thats only for peak loads, it can only draw so much for short times, i think its max 10-20 seconds.
And you have to think about the capacitors too, they are 2x 22000 µF 80V 85°C which is quite beefy for AVRs. Yamahas MX-A5000/5200 11 channel amplifier has 54000 µF which is only 10000 more than the Denon.
In the European Union there are regulations for electronics like this, @voodooless mentioned the specs for the EU.
I don't know about regulations from other countries but it would be a safe bet to rely on the EU ratings.
Actually the US and EU version Information sheets say exactly the same regarding power consumption
[QUOTE = "lashto, post: 470673, member: 6743"] A 2-3 veces el precio, debe comerlo crudo
En caso de que hiciera comparaciones serias / extensas, algunas impresiones de sonido adicionales podrían ser útiles. [/ QUOTE]
no en mi caso, ya que tenía un 7013 que compré nuevo por € 1400 más un emotiva basx a-700 para surround y atmos que me costó alrededor de € 700 ... mi denon 8500h estaba en exhibición con una garantía de dos años por 2200 Así que vendí el emocional sr7013 + y fui a denon que me costó lo mismo y ganó en todas las tramas.
En caso de que hiciera comparaciones serias / extensas, algunas impresiones de sonido adicionales podrían ser útiles. [/ QUOTE]
no en mi caso, ya que tenía un 7013 que compré nuevo por € 1400 más un emotiva basx a-700 para surround y atmos que me costó alrededor de € 700 ... mi denon 8500h estaba en exhibición con una garantía de dos años por 2200 Así que vendí el emocional sr7013 + y fui a denon que me costó lo mismo y ganó en todas las tramas.
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OP
- Thread Starter
- #333
For those of you waiting for the AVR-X3700H review, just received sign-off from Denon on the measurements. Still have to test one more thing, take pictures, write the review, etc. So I will likely post the review tomorrow.
Another sleepness night!
Wonder how it compares generally to the 3600. Will be looking forward to the review.
Wow, I hope those who put pressure on you will pay up, at double OT rate.
Oh, please be reminded to verify if the analog input digitization in Stereo depend on speaker/sub settings and/or whether Audyssey is on, and not just applicable to the CD input, whereas in direct mode it doesn't get digitized regardless. Thank you.
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Another sleepness night!
More to come yet, he still has the flagship in the queue.
Before you pack it up, can you run some measurements with the ALPHA test tones. You don't need to publish -- but when the fixed X6700h comes back, you'll at least be able to see what the difference between no-AL32 and yes-AL32 looks like (compared to conventional 20-bit ALPHA)
Torpedoes away!
OP
- Thread Starter
- #340
I have run that test (some of it anyway).
