LOL - there is no substitute for torque (in cars), and current (in amps)
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Denon AVR-X3800H Review
- Thread starter amirm
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There is always a compromise. Many of these amps will have significantly more distortion when driving 2R loads:
The Krell is already shit in 8R, 2R will be horrible.
Even the new Hypex amp has a bit lower distortion, but much less so:
That’s still 0.00025% @20W into 2R compared to the 0.04% of the Krell at 8R or 0.025% of the 333 into 2R.
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Yep - we do have progress.... on the other hand, threshold of audibility.... as long as we are below 0.1%, the amps are likely to be indistinguishable in DBT... (as long as they are within their operating envelope - and the above amps have some of the widest operating envelopes around!)
X4700
Hobolicious
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Really depends what you are after. X3800H obviously have a few features that the X4700H lacks, so if any of those are necessary to you then you would have to go with the X3800H, if you don’t see the need for any of them obviously X4700H is a better fit. Performance wise they will probably be very similar (especially on «newer» X4700H which will have the same DACs as X3800H).
So ask yourself:
- Do I need/want Dirac down the line?
- How many HDMI 2.1 inputs do I foresee needing long term?
- How many subwoofers will I be running long term? Would I want to run transducer?
- Is better flexibility in terms of pre-out options important to me?
- Is the updated GUI important to me?
Probably something I missed, but those could at least be some of the questions to ask yourself to see if features on the X3800H would sway you in that direction.
beagleman
Major Contributor
Yes and no.
Every one you mention, is not doing what I said though.
They are all giving good output at LOW impedances only.
You must have a variable output on the power supply to do great at both very low and high impedances.
I am not saying they will be crap or this is the "end of the world", but it is rarely mentioned in the last few decades.
It is simply an ohms law thing.
Not how GOOD the amp is or how "robust".
An amp with great output at 2 ohms will simply compromise output say for instance with a 16 ohm speaker as an extreme example.
I think you are missing my point. The examples you give with high power at 2 ohms are all fine, but they are doing it at the expense of high power at NORMAL Impedance speaker ratings.
Power output can only be optimized for a small range of output impedances is the point.
Make it have great power at 8-16 ohms and it will be "Weak" at 2-4 ohms or not even usable.
Make it have great power at 2-4 ohms and it will consequently have low power at 6-16 ohms.
Bren Derlin
Active Member
What IF... Robinson doesn't have a bias?
Either Robinson can't detect the distortion, which proves the measurement is meaningless, proving everyone's anxiety over the x3800H is also meaningless. ...or he can hear the distortion, validating the measurements and proving the x3800H is a product to avoid.
You're going to have to pick one and move on with your life...
That's a big IF, and until that is determined, I think it's best to disregard his claims and move on as if he never made that video.
Not really, because I think beagleman 's point is not (or not just..) about the double down capability but also what he said in his last sentence "An amp great at low impedances, by its very design will lose performance at higher or normal impedance"
The AHB2 can almost double down into 4 ohms, but definitely not 2 Ohms.
As beagleman predicted, it "performance at higher impedance....", in this case, only 100 W into 8 Ohms, that is clearly not due to current capability but most likely voltage capability.
Take a look of the voltage requirements for the varying load impedance, based on the same current capability (Power = V^2/R, or I^2*R):
Voltage = square root of P*R,
I = square root of P/R
For 190 W, 4 ohms, Voltage required = square root 190*4 = 27.57 V, and Current = square root of 190/R = 6.892 A
Since it is capable of 6.892 A, the theoretical power output capability should be:
Power (W) = I^2*R = 380 W into 8 ohms, but the amp is only rated 100 W into 8 ohms. This amp may not perform as well when driving certain so called 8 ohm nominal, but with high peak impedance speakers than those nominal 4 ohms with low dip ones, when operating at or near its power output limit.
In short, if an amp is designed to double down (that is almost double down), it will have trouble to "double up". Hence a compromise, that need to be done for the targeted type of load for the targeted applications.
That's the nice thing about objective measurements, I most likely don't agree with @beagleman based on his/my subjective views/preference, but on the objective side, I have no choice but to agree with him on things he posted that are based on engineering principles.
Based on Benchmark's website information for the AHB2's power output for various load impedance:
CONTINUOUS AVERAGE OUTPUT POWER
< 0.0003 % THD+N at full rated power, 20 Hz to 20 kHz- 100 Watts per channel into 8 Ohms, both channels driven
- 130 Watts per channel into 6 Ohms, both channels driven
- 190 Watts per channel into 4 Ohms, both channels driven
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Your equations make it quite obvious why it can only do about 100W. You only have 27V at your disposal. That will give you 91W into 8R. Let's assume the voltage will sag less at 8R, then the 100W is correct. You'd need 55V to get 380W.
There are other possibilities, bias or not. For example (just one example), the x3800h might have been pushed to near, or even further beyond the amp's clipping point than what he did when listening to the Marantz. I have no issue with his claim about hearing distortions, but am skeptical about the way he implied the C50 sounds better in that it didn't distort audibly like the X3800H did.
No issues with his opinions on (those over the top flowery narrative) on why the C50 sounded so much better, simply because that's the nature of many subjective review that cannot be disapproved unless we are there with him at the time, then we may have a chance to try something otherwise it is entirely up to his followers to think whatever they think about his opinions.
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Are you sure? Doesn't it depend on your interpretation of "this".
PS - I stated my interpretation in my response.
A little more than 27 V, so 100 W is about right for sure without even considering the slightly less voltage drop for 8 ohm loads.
I was thinking about getting the Denon X4800H and I have a question.
I have an amp that is rated at 1V for input sensitivity (29db) and my front stage is rated at 98dB with the center being 97dB.
If some online calculators are correct and more importantly I am understanding all of this, that would mean that I would be well above reference levels at 50w or 100w which would mean less than 1V.
So again if I am understanding this correctly.... Wouldn't that mean that the actual SINAD that would be coming out of the Denon would be greater that 90dB and not be an issue for my setup?
Thanks in advance!
I have an amp that is rated at 1V for input sensitivity (29db) and my front stage is rated at 98dB with the center being 97dB.
If some online calculators are correct and more importantly I am understanding all of this
, that would mean that I would be well above reference levels at 50w or 100w which would mean less than 1V.So again if I am understanding this correctly.... Wouldn't that mean that the actual SINAD that would be coming out of the Denon would be greater that 90dB and not be an issue for my setup?
Thanks in advance!
Narnian
Active Member
For those that wanted an upgrade but are skipping the X3800H for whatever reason Denon now has the X3700H at $1,199 close out on their web site.
www.denon.com
AVR-X3700H - 9.2 Ch. 105W 8K AV Receiver with HEOS® Built-in | Denon - US
The AVR-X3700H 9.2 Ch. 105W 8K AV Receiver with HEOS® Built-in from Denon provides high quality audio for your hi-fi needs. Explore more AV Receivers at Denon - US.
You'll need to factor in the listening distance, but yes, 98 dB speakers (can they manage that down low as well?), will be very loud with only 50W already. Now the question is: when are you ever going to listen that loud? Isn't the amps SINAD worse than the AVRs? In any case, I would not worry about it too much.I have an amp that is rated at 1V for input sensitivity (29db) and my front stage is rated at 98dB with the center being 97dB.
If some online calculators are correct and more importantly I am understanding all of this
So again if I am understanding this correctly.... Wouldn't that mean that the actual SINAD that would be coming out of the Denon would be greater that 90dB and not be an issue for my setup?
you can do a lot better. Quoting you to yourself should be quite popular
Everytime when measurements are below expectations there is this big 'dance': the review/er is wrong, measurements do not tell everything, SINAD/etc are irrelevant and so on..
The new/original part in this thread: a lot of 'strange' posts about the SINAD number and audibility. All ~wrong by default since those two were proven again and again to be not correlated. But even 'more wrong' than usual here: some seem to think that distortion is just "one thing", some think that even SINAD 60 is not audible, some seem to think that all speakers have SINAD over 70 (my choice as the most 'new'), some think that SINAD X is generally more (or less) audible than SINAD Y... and many of those posts have a disturbing number of upvotes.
I would recommend everyone to read the above linked post very carefully, especially points 1,4,6.
Spoiler: no1 gives a much better number where you may start to assume that SINAD is no problem. A lot bigger than this AVR's 87 and even that number is just a sort of guess/assumption. Like pretty much every other connection that people make between SINAD and audibility.
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@voodooless Thank you for the quick reply.
Distance to the sweet spot is 9 feet away from LCR and I have multiple subs so my crossover is 80Hz for all channels. I generally listen to movies at -10 and sometimes reference level. (Top Gun) So that would be what... 75dB to 85dB?
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