Denon AVR-X3800H Review

[dlaloum]

No one disagrees with the need of current in amps, others are just saying there is a need for voltage as well and of course ideally an amp should have both high voltage and high current capability. But that would, as you mentioned before, involved some "heavily engineered...", and obviously relatively expensive parts.

I just randomly googled the impedance graph of one of the often mentioned as a difficult load, see those high impedance peaks beagleman talked about?
Now we have both examples, one from you about the impedance dip to near 2 ohms and this one with peaks to higher than 20 ohms.

The Quad amp you mentioned before may not struggle with your low impedance speaker under some conditions but it would struggle with speakers that have such impedance peaks under certain conditions of use.

Again, I agree with you that there are amps designed to maintain excellent performance regardless of the impedance peaks and dips. That's in theory, in practice I am not ware (they probably do exist) of any power amp that are truly designed to perform equally well with speakers that have relatively high impedance peaks and low dips in the frequency range that have a lot of contents. McIntosh use output autotransormers (they call them autoformers) for impedance matching purposes but the user have to manually move the connections if they switch from 8 ohm to 4 ohm speakers, so it is still not ideal for speakers that have both high impedance peaks and low impedance dips I mentioned. That's just all theory, in practice also as you mentioned before, no one need to worry about sacrificing performance as there is always the option to just buy more "power". So if one needs 100 W/160 W 8/4 ohm amp, then just go for a 400/600 W 8/4 ohm amp and all those wonderful 20 ohm peaks and 2 ohm dips will be forgiven!!

By the way, for a relatively low cost solution, bridging a pair of AHB2 can also be a good option for those who has such speakers.

Bowers & Wilkins 802 D3 Diamond loudspeaker Measurements

Sidebar 3: Measurements

www.stereophile.com

Yes - we seldom talk about impedance peaks - mostly because they are easily handled by the vast majority of amps - Impedance peaks aren't a "problem"

And the other things is - even without "power doubling" as impedance drops - many of us make do, by purchasing massively overpowered amps, just so we can have sufficient at the low impedance!

I purchased the Crown XLS2500 at a very attractive price - but an XLS1500 would probably have done the job just as well. (the XLS2500 is 440W@8ohm, 1200W@20hm)

Talking about voltages... standard 1W SPL measurements are done at circa 2.8V... and to maintain that V at 2 ohm requires 4x the current

One can calculate the required V for the required SPL... it's a bit like looking at the other side of the same coin....

With my 86db SPL speakers at 2m, 2 speakers (stereo pair) -

1W@8ohm / 2.8V produces 83db SPL (4W@ 2ohm)
16W@8omh / 32V produces 95db SPL (64W@2ohm)
128W@8ohm / 90.5V produces 104db SPL (512W@2ohm)

So in a rough, manner, if you want to achieve 105db SPL at MLP (with 86db spl speakers) - you need and amp that can put out just under 95V into whatever impedance your speaker throws at it.... that means, for a speaker that has 2 ohm troughs in its impedance, it will need to be over 500W @ 2 ohm

And this, naturally, is where AVR's as a general genre, usually "hit the wall" - and where people like me, choose to use external amps, and very high powered ones - for all of those reasons.

It also shows up what power levels are needed (roughly) to achieve THX reference levels with a relatively inefficient set of speakers... 130W (@ 8ohm) is ample, no real need for 150W+ "monsters"..... but because of those 2 ohm troughs, we end up running 300W+ "monsters" - just so we can eke out the minimum power/voltage we need at 2 ohm without being constrained.

 

[evert]

Has anyone sent a Cinema 50 to Amirm yet?

 

[peng]

Yes - we seldom talk about impedance peaks - mostly because they are easily handled by the vast majority of amps - Impedance peaks aren't a "problem"

Sure, but that's what some of us have been saying to you that the example you cited before (forgot what speaker, that dip to below 2 ohms) was also a rare case scenario. You can say the same about impedance dips are "easily handled by the vast majority of amps. As to "easily handled......", while not disagreeing, I would have to say that doesn't sound right, only because you started using the extreme like case examples. That is, in extreme case, it is not that easy to handle certain kind of impedance peaks either.

"easily" is a relative term, and to say impedance peaks aren't a problem is similar to saying impedance dips aren't a problem, though neither is true in extreme cases, such as the example you cited several times. I only cited the B&W speaker's impedance peaks and dips as an example for you to see both could be an issue for a lot amps and only because in one post you seem to have trouble with beagleman's point about the need for optimizing for "...range of impedance..." and now you reinforce that by saying "whatever impedance your speaker throws at it..."

To stick with facts and not just opinions, take a look of your own example:

So in a rough, manner, if you want to achieve 105db SPL at MLP (with 86db spl speakers) - you need and amp that can put out just under 95V into whatever impedance your speaker throws at it.... that means, for a speaker that has 2 ohm troughs in its impedance, it will need to be over 500W @ 2 ohm

95 V would be able to deal with both 2 ohm dips and 16 ohm peaks but not the B&W's > 20 ohm peaks (example, the one at around 50 Hz), yes a subwoofer can help.
Also, 95 V rated amps with 3 to 5 kVA power supply transformers are sort of a rare commodity at below $50,000 aren't they, so let's avoid using extreme examples that probably 90% of ASR members don't think about.

And again, from start, no one argued with your point that 2 ohm loads need "high current", but speakers with 2 ohm "trough" impedance are relatively rare, that's all we having be saying. Sharp dips like that may not be too uncommon (still relatively rare), but trough? Likewise, there aren't too many speakers that have impedance peaks >20 ohm either, I cited that B&W speaker just to show if extreme examples are used, then one need to look at both side of the coin too, that below 2 ohm dips, even troughs are probably as rare as the above 20 ohm peaks.

To conclude if I may, you made the case loud and clear already, that there are people like you who need very high current capable amps such as those that can truly be rated to almost double down to 4 and then 2 ohm, but for most people who can avoid owning the truly difficult to drive speakers, amps rated 200 W 8 ohms, 300 W 4 ohms are fine if they don't feel comfortable using their AVR amps. Case closed, I hope.

 

[dlaloum]

95 V would be able to deal with both 2 ohm dips and 16 ohm peaks but not the B&W's > 20 ohm peaks (example, the one at around 50 Hz), yes a subwoofer can help.
Also, 95 V rated amps with 3 to 5 kVA power supply transformers are sort of a rare commodity at below $50,000 aren't they, so let's avoid using extreme examples that probably 90% of ASR members don't think about.

Mostly, we agree....

I became aware of the impedance/current/voltage issue some time after purchasing my "current" speakers (Gallo Reference 3.2) - and then experimenting with different amps...

I ended up purchasing a used pair of Crown XLS2500 - which are 100V capable, can drive 1200W@ 2 ohm, and don't cost $50,000!!!

But if you aren't aware of the issue and its ramifications, you aren't likely to seek out the solutions for it.

Many Martin Logan electrostatic speaker owners have also jumped on the Crown XLS bandwagon for that very reason... an economical (used to be downright cheap!) amp that can drive a speaker like the ML that goes down to 1 ohm.

I have no idea how the XLS would handle a B&W with 20 ohm peaks.... I don't own those B&W's! (would be an interesting experiment...)

 

[Fosi Audio]

Great AVR, we have noted AVR very early and want to develop a fosi audio AVR, but we still have not started that project. Because there is one main question that I can't figure out, why there are so so many inputs on AVR, and who will use them?

 

[Trell]

Great AVR, we have noted AVR very early and want to develop a fosi audio AVR, but we still have not started that project. Because there is one main question that I can't figure out, why there are so so many inputs on AVR, and who will use them?

Apart from HDMI or you think there even are to many HDMI inputs?

 

[delta76]

Great AVR, we have noted AVR very early and want to develop a fosi audio AVR, but we still have not started that project. Because there is one main question that I can't figure out, why there are so so many inputs on AVR, and who will use them?

AVR is created to be the central of your home audio/theatre system. You're expected to connect every source in it. At enthusiast level it could easily be 3-4 or more inputs, and to make sure you can cover large customer base you need to add almost all common inputs.

I need 5 HDMI input now (1 xbox, 1 ps5, 1 switch, 1 bluray player, 1 streamer), will probably need 1 more (apple tv), and I am not even an "enthusiast"

 

[Music707]

Great AVR, we have noted AVR very early and want to develop a fosi audio AVR, but we still have not started that project. Because there is one main question that I can't figure out, why there are so so many inputs on AVR, and who will use them?

Why don't you open a separate thread with some kind of poll to collect more information?

 

[Bren Derlin]

AVR is created to be the central of your home audio/theatre system. You're expected to connect every source in it. At enthusiast level it could easily be 3-4 or more inputs, and to make sure you can cover large customer base you need to add almost all common inputs.

I need 5 HDMI input now (1 xbox, 1 ps5, 1 switch, 1 bluray player, 1 streamer), will probably need 1 more (apple tv), and I am not even an "enthusiast"

This! 6 should be the minimum number of inputs if you want gamers to buy your product.

 

[peng]

Mostly, we agree....

I became aware of the impedance/current/voltage issue some time after purchasing my "current" speakers (Gallo Reference 3.2) - and then experimenting with different amps...

I ended up purchasing a used pair of Crown XLS2500 - which are 100V capable, can drive 1200W@ 2 ohm, and don't cost $50,000!!!

But if you aren't aware of the issue and its ramifications, you aren't likely to seek out the solutions for it.

Many Martin Logan electrostatic speaker owners have also jumped on the Crown XLS bandwagon for that very reason... an economical (used to be downright cheap!) amp that can drive a speaker like the ML that goes down to 1 ohm.

I have no idea how the XLS would handle a B&W with 20 ohm peaks.... I don't own those B&W's! (would be an interesting experiment...)

In most cases, such peaks and dips are not a problem. Well designed amps, including many AVR amps, should be able handle the common peaks/dips that most speakers may have unless you listen mainly to test tones, or certain music that the musician(s) on bass drums or double bass etc. non stop.

I have never seen the specs and/or measurements of the Gallo Reference 3.2 speakers but if you could power it with a Quad 606 and yet you need the XLS2500, then something just don't sound right. There must be something else then can explain the issues you experience, just a 1.6 ohm dip won't cut it. If the dip is like a trough, then the little Quad rated for less than 200 W wouldn't be suitable unless you sit close and/or listen at relatively low level. For anyone who is interested to dig into the technical reasons, it would need a separate standalone thread with full specs of that particular speaker.

 

[Dj7675]

It doesn’t matter whether you implement the e with boosts or cuts. The nominal level will be about 10 dB down. So either way, you’ll loose that headroom.

@peng
In another thread HERE @Flak confirmed the approximately 10dB down when Dirac is enabled to account for any boosts etc when Dirac is enabled. From his comments this seems to be adjustable in the PC version and maybe the MiniDSP version (Could be wrong). My non expert take on this is from his comments and personal experience, when Dirac is enabled you may need to turn up your volume 8-10dB vs without Dirac enabled. Doing this would raise the noise and distortion levels after increasing the volume. To me this is important information and a good reason to shoot for the best SINAD possible.

 

[Kylo Ren Amamiya]

Other than the extra HDMI 2.1 ports on the X3800H, is the HDMI board updated and offer improvements over the X3700H’s HDMI board?

 

[delta76]

Other than the extra HDMI 2.1 ports on the X3800H, is the HDMI board updated and offer improvements over the X3700H’s HDMI board?

What updates/improvements do you expect? Either hdmi ports work with hdmi 2.1 or they don't.

 

[Kylo Ren Amamiya]

What updates/improvements do you expect? Either hdmi ports work with hdmi 2.1 or they don't.

Since the X3700H had HDMI 2.1 issues and was updated in May 2021 I was wondering if the X3800X used the same updated HDMI board.

As far as improvements I was more interested in quality of the HDMI board. If anything had changed compared to the X3700H.

 

[delta76]

Since the X3700H had HDMI 2.1 issues and was updated in May 2021 I was wondering if the X3800X used the same updated HDMI board.

As far as improvements I was more interested in quality of the HDMI board. If anything had changed compared to the X3700H.

It was because of buggy chip. It was long fixed and I don't think they will not test it thoroughly this time.
All in all you got covered by 30-60 days money back guarantee, and 3-5 years of warranty. Of all issues that might happen to x3800h, hdmi board is least of my concern. It is easy to check and claim warranty for.

 

[peng]

@peng
In another thread HERE @Flak confirmed the approximately 10dB down when Dirac is enabled to account for any boosts etc when Dirac is enabled. From his comments this seems to be adjustable in the PC version and maybe the MiniDSP version (Could be wrong). My non expert take on this is from his comments and personal experience, when Dirac is enabled you may need to turn up your volume 8-10dB vs without Dirac enabled. Doing this would raise the noise and distortion levels after increasing the volume. To me this is important information and a good reason to shoot for the best SINAD possible.

Thank you very much for the link. So that explained why you and I have had different experience, finally!! I did mention my only experience with Dirac Live is with the PC standalone version and I also mentioned whether it was "down" by whatever dB would depend on the adjustment.

I find it strange that it is only adjustable with the PC version, but regardless, the same principle really applies to all RC software including Audyssey, YPAO, even the typical tone controls. That is, if boost the signal you will eat into the headroom, and it is up to the user to avoid boosting much more than a few dB. I used minidsp for a while and if I remember right they also mentioned something about boosts.

Also, in practice the big power requirements are typically for the bass and lower mid range so it really isn't a concern in most cases hence the reason we you don't see much user complain about hearing distortions after running the RC auto setup because:

a) boosts, if done, would have been mostly in the Subwoofer's range.
b) even when boosts were done in the higher frequency range, the amps, even AVR amps can handle it fine because the magnitude of the music signal is not constant, and amps can output much more than the average Vrms on short duration basis (such as 20 ms, up to 1 second or even a few seconds).

 

[peng]

It doesn’t matter whether you implement the e with boosts or cuts. The nominal level will be about 10 dB down. So either way, you’ll loose that headroom.

May be may be not.. I can't/won't agree or disagree without knowing what you are really talking about, and your definition of "headroom" in this context.

 

[voodooless]

May be may be not.. I can't/won't agree or disagree without knowing what you are really talking about, and your definition of "headroom" in this context.

It’s a simple matter of not having the signal clip. Either you do that by cutting the high parts, or by boosting the low parts. In the latter cast, you’ll need to lower your gain to prevent clipping. Effectively that makes both method equivalent.

 

[Vincentponcet]

No. Seems like you pulled that 1.1V number from the X3700H chart which was only included for comparison. Even on that chart, 1.1V is only the point where SINAD reaches a maximum and does not represent the output limit of the pre-amp.

It dramatically fall above 1.4V, so with the audiophonics purifi which has a gain of 25db, max 77 W are effectively available.
So, the limited gain of the audiophonics and the limited output of the Denon preamp will give either low power or bad performance.
Very sad.
Apollon provides gain selector for 12,8/20,5/27,5/29 db, but is significantly more expensive, and was never tested here.

 

[peng]

It dramatically fall above 1.4V, so with the audiophonics purifi which has a gain of 25db, max 77 W are effectively available.
So, the limited gain of the audiophonics and the limited output of the Denon preamp will give either low power or bad performance.
Very sad.
Apollon provides gain selector for 12,8/20,5/27,5/29 db, but is significantly more expensive, and was never tested here.

It drops to 75 dB at 2 V, and that's in non preamp mode. It's not dramatic if you compare with its cousins such as the AV7705 that is a "separate" prepro.