Sounds logical.
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Denon AVR-X4800H AVR Review
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soerenssen
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What pre/pro and amp are you using if I may ask? And what speakers are they driving?
I am using a lower end Anthem avp (AVM70), and 3 power amps, MM8003 for surround, M2200 for the center, and MCA20 for FL/FR.
Speakers: Energy Veritas 2.3i
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I recorded a short comparison video of Yamaha A3080 vs Denon 4800H.
Frankly after calibrating SPL levels of both receivers to ~60 dB, they sound more similar than not, yet Yamaha being slightly brighter/edgy (clear?) to my ears - the reason could be better DAC in Yamaha, and/or extended HF response comparing to Denon, just speculating.
Very decent bass extension from the organ, towers only or with sub(s)?
pogo
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That was already intended for you and referred to your complete post
If you don't follow the manufacturer's guidelines, you shouldn't be surprised if the amplifier sections or the tweeters are pre-damaged and fail sooner or later.
...we couldn't convince him otherwise...is totally out of context and you can hear that even before!
Towers only, double 8" woofers.
Since you mention 2 ohms, I suspect you may still be thinking about the so called 1.8 ohms EPDR shown in Erin's measurements. Let me try to clarify that a little more:
EPDR is Equivalent Peak Dissipation Resistance. You cannot use that value to calculate current draw by the speaker. Current, still has to follow Ohm's law, current = Voltage/Resistance, or for impedance, current, I = V/(|Z|), |Z| is the absolute value of impedance. The low value of EPDR vs just impedance does not change the calculated current, it just changes the calculated heat dissipation by the amplifier.
For example, if impedance is 3 ohms, EPDR is 2 ohms, at a given voltage, say 30 V, the current flow is still going to be I = V/|Z| = 30/3 = 10 A, not 15A (A is ampere), but the heat dissipation will be expected to be equivalent to that resulted from a load with impedance = 2 ohms. I hope this does not confuse you.
To see how EPDR is calculated, read jackocleebrown's post:
Stereophile has started calculating EPDR.
https://www.stereophile.com/content/goldenear-brx-bookshelf-reference-x-loudspeaker-measurements And he is going back to previous reviews and adding this in. EPDR (Equivalent Peak Dissipation Resistance) takes the impedance and phase data and computes a new impedance that shows what equivalent...
www.audiosciencereview.com
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I would say there is no need to convince him any more, if you mean @soerenssen, he already knows what the 4-ohm setting is for, after being linked the Audioholics article. Our discussions has been about using that setting, and/or take precautions to not crank the volume above 50-60. For Denon, you probably know that using 82 as reference (based on ASR measurements), even at 60, it would be 22 dB below reference, so the amp output voltage would be quite low, mostly likely below (don't want to say 100% sure just in case) the rail voltage limit for the 4-ohm setting. Anyway, I think he is convinced to look for a power amp such as those based on the NCx, with appropriate SMPS. Until then, I trust he would use the 4-ohm setting. He seems like someone who is very careful about the whole thing, it is very unlikely he would damage the tweeter or the Denon.That was already intended for you and referred to your complete post
If you don't follow the manufacturer's guidelines, you shouldn't be surprised if the amplifier sections or the tweeters are pre-damaged and fail sooner or later.
...we couldn't convince him otherwise...is totally out of context and you can hear that even before!
pogo
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This is not correct. Perform a reactive load test and you will immediately recognize the problem of conventional AVRs. The voltage drop is still the least evil.
soerenssen
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Correct. As long as I don't get a new power amp, I'll use the 4 ohm setting. Stereo at max. 60dB. I am watching Mad Max Fury Road and I had to increase the master volume to 65dB because at 4ohm setting I don't understand speech coming from the R6 Meta center. Either 8ohm setting at lower master volume level (and the top of the AVR getting hot quickly) or 4ohm at around 5dB higher (and the top of the AVR staying a bit cooler that will be easily addressable using active cooling. I'm hearing more details / better clarity at higher volume levels. So instead of DAC improvements, more power seems to be the way to go. The difference is easily noticeable when listening to speech from the center.
It is really time to do a new Dirac calibration too (along with REW) so I expect things get better soon!
ban25
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My advice remains:
1. Apply a house curve with Dirac
2. Confirm results with REW
3. Buy a subwoofer
Any differences between amps, once properly level-matched, will be impossible to discern in a blind A/B test. The KEFs, with their small 6.5" woofers, are unable to compete with a good 8-12" subwoofer. Consider KEF's specifications for the KF92: -3 dB at 11 Hz compared to those of the Reference 3 Metas: -6 dB at 28 Hz.
As far as the heat is concerned. The majority of it is from the AVR's HDMI board and internal processing, and that will be active no matter what speakers are driven. I ran my full 5.1 setup on a Denon X3700H for a year -- no external amplification -- and had no issues with heat or clipping.
Volume at 65 is still safe, but please do use an ext. fan. As explained before, the artificially lowered EPDR value is used to account for the much higher heat dissipation, it is a thermal issue so you can mitigate the effects by using active cooling.
I think I have done the calculations, before but maybe appropriate to repeat it at this point:
Based on Amir's measurements, the X4800H's pre out is about 2 V, with volume at 82, and input HDMI at 0 dBFS (see pic of the dashboard below).
With Pre out voltage at 2 V, the Power output at 8 ohms will be about 400 W, or 800 W into 4 ohms, based on the Denon's gain of 29 dB.
So at 62 dB volume, that is a drop of 20 dB, power output will drop by 100X, that is 8 W into 4 ohms.
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At 65 dB volume, power output will double to 16 W into 4 ohms.
Now, if you assume the EPDR is 2 ohms overall, the heat dissipation in the Denon amp will then be double again, that is 32 W into 4 ohms.
I think we can all agree that 32 W into 4 ohms is still within the Denon's power limit even with impedance setting set to 4-ohms. Reminder: This is "equivalent" based on heat dissipation. In reality, at volume 65, your spl calculation is still going to be based on 16 W into 4 ohms. If you want to know the spl you can achieve under such conditions, use the online calculator, or give me the distance and I can do it for you.
There is still some room to go higher, but to be on the conservative side, and being at the 4-ohm impedance setting, volume 65, that is -15, is probably the limit you should adhere to and not exceed it. At this level, you can still stay clear from the Denon's clipping point.
Note: Calculations based on volume setting above assume direct mode, if Audyssey is in use, check the level trim settings and if they are not at 0, then adjustment to the volume limit of 65 need to done (up or down) accordingly. Audyssey may also apply boost to the bass, though I wouldn't worry too much if you are using subwoofers and set crossover to 80 Hz.
The above calculations are based on Amir's actual bench test measurements, as shown below:
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Do you read the posts before responding?
Again, no idea why you keep saying things not related to the topics being discussed.
Who said anything about volrage drop?
If there is anything incorrect, it is your generalized, blanket statement about avrs being a problem driving reactive loads.
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pogo
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I say that. We are talking about real sound events at a real load in the real world. Idealized assumptions are not appropriate here and the protection circuits are also not designed to work properly outside the AVR spec - this guarantees a deterioration of the MTBF! An inquiry to the manufacturer Denon recently confirmed the following to me:
Dear Mr. xxx,
thank you for contacting us.
As you can see from the technical data, we recommend connecting speakers with an impedance of 6 to 16 ohms for most devices, and 4 to 16 ohms for some models such as the Avr-X4800H. Any type of speaker with this nominal impedance can be used without hesitation.
The nominal impedance is the specification of the resistance at rest. During operation and with increasing volume, the actual impedance can deviate greatly from the nominal impedance. In addition, the impedance is frequency dependent. The impedance can then assume values significantly below the nominal impedance to below 1 Ohm. With the variety of models offered and the most diverse properties, we can therefore not make a generally binding recommendation. Since a low impedance means an increased power output and thus a higher heating of the amplifier, a critical operating condition can be reached, which could mean a defect in the amplifier or the speakers.
Therefore, make sure that the minimum impedance (in the entire frequency spectrum) should generally not fall below a value of 3.2 ohms.
With current AV receivers, you can change the impedance of the connected speakers using a key combination described in the operating instructions. If you select 4 ohms here, the amplifier limits the available power to prevent overloads.
So in your case, the Nubert nuLine 34 speakers are not recommended. --> Here are the speaker measurements including EPDR: Link
With best regards
Your Product Support Team
Translated with www.DeepL.com/Translator
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soerenssen
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If your speakers don't go lower than 3.2 ohms, why don't they recommend them? Is it because of the EPDR dips below 2 ohms? They assume full range, so cutting off lower frequencies could keep your AVR and speakers on the safe side.
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To be honest, I would have made the same recommendation. If using only internal amps, the 4800 is better. The 3800 is ok as long as you send at least 2 channels (typicall L and R) via pre-outs to beefy, external amps. That's what I've done for my L/R channels by sending them to my 2nd gen Emotiva XPA2.
I wouldn't waste time trying to figure out what he's saying, I tried and realized it's a waste of my time so I am done with that..
I think it has to do with translating from German, and something got lost in translating.The speaker's impedance/phase angle he linked is however, a good example for us, thanks to him
Using the translator he linked (thanks Pogo for that again):Even without seeing that, you can read directly from the curves he included:
I marked up the area of concern. You can see that not only the impedance dips below 3.5 ohms, it also spans a wide range, from 150 to 700 Hz, that's more than 4 octaves!!
Music (including vocal, male or female) and movie contents have a lot of energy in that range and the amp will obviously spend a lot of time working hard in that range. That is not the same with a narrow dip to around 3 ohms for the KEF reference speakers in less than one octave.
The low EPDR curve helps emphasizing the issue for people who naturally are familiar with impedance but not phase angle so it is useful that way. And it works, as it obviously got your attention because of the low EPDR below 2 ohms, if you only look at the impedance, you might feel good just using such speakers with a so called 4 ohm rated class AB power amps.
My point to those who tend to get fixated on one or two thing is that while it is good to have much more "power" than what is actually needed, a lot of people can actually get by with their AVRs, even for difficult to drive speakers like the one used in this example. For example, someone using the speakers near field, say at 2.5 meters, and anything louder than 85 dB maximum (peak), 65 dB (average) is too loud for him/her, than something like the AVR-X4800H can do the job nicely. Manufacturers are not going to tell you that for the obvious reasons, good reasons. What you can do, is not the same as what you should do. If I have speaker like this one, or even your reference 3 Meta, I will definitely not use an AVR, any AVR. In fact, I wouldn't use any class AB amp rated less than 500 W 4 ohms either.
The good news is, apparently, class D amps, such as the ones you are considering, is not going to be bothered by the low EPDR, so if you go with the NCx amps with adequate SMPS, you don't have to worry about the EPDR values. I say apparently because I am relying on the information from the ASR thread I linked before, in which some amp designers/experts provided some insight on that, but there no definitive "proof" in any of the posts that I can remember, though whatever argument presented seem would make sense. Regardless, if you are going to use the amps you mentioned earlier, EPDR or not, you are well covered.
Stereophile has started calculating EPDR.
https://www.stereophile.com/content/goldenear-brx-bookshelf-reference-x-loudspeaker-measurements And he is going back to previous reviews and adding this in. EPDR (Equivalent Peak Dissipation Resistance) takes the impedance and phase data and computes a new impedance that shows what equivalent...
www.audiosciencereview.com
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This is the last time I respond to your post, as I find it difficult to understand your purpose of responding to my posts. I have no issue with what you stated, and no issue with Denon's response to you, but I do not understand why you keep telling him those things when there has been nothing I said in my posts that would trigger such responses from you. In fact, I have been practically saying the same things to the op, that is @soerenssen, but I said those things to him in response to his questions. In contrast, I have never asked you a single question, except one, that is, the reason why you keep responding to my posts instead of responding directly to the person who asked the questions that you may feel necessary to respond.
That's what puzzles me, nothing against you, nothing personal,
just don't see the point going back and forth.., for no reasons at all. Lastly, thank you for the link to the Nuber nuline 34 speaker's impedance/phase angle curves, I would keep that for future use as example of truly difficult to drive speakers.