Denon pre-amp mode sound quality vs utilization of internal amps

[New_Guy]

Hello team.
This may be a box of worms, I’m new to the forum thing so apologies in advance.

I have a Denon x4700H.

Currently I’m running 5.2.4 (arendal 1961 bed layer & subs, RSL C34E in-ceiling for Atmos)…
L/C/R powered by Emotiva bas-x A3, and remaining channels are powered by the Denon’s internal amps.

I’m wondering if anyone has first hand experience with sound quality/ clarity/ ‘channel separation’ comparison between this model year (3700, 4700, 6700, 8500H) using internal amps (any number of channels), and not (pre-amp mode).

Is there a meaningful/ audible difference?
Or
Is the only next move fully transition into separates?


I understand I will need additional external amplification if separate’s is the way, as well as a “true” pre/pro… so I’ll end up crying at least a little.

I feel like it’s not a great time to make any major purchases for AVRs/ Processors, with the current climate, and model updates just around the corner…
Also, I’m quite curious about the new Denon AVRs that are compatible w/Dirac live.
But; Again, if there’s no meaningful/ audible improvement in pre-amp mode, maybe I’m just better off saving for a “true” pre/pro.

I’m very curious about the real world performance differences between Audeyssey XT32 vs Dirac vs ARC (but that’s a whole other conversation, I know).

I’m aware I’m sorta chasing the dragon here. There comes a point of diminishing returns.
Are separates really “worth it”. Or am I wasting my time/money. I’m not going to a trinnov or anything.

Thanks for any input, well appreciated!

 

[lovinthehd]

Using the full pre-amp mode may gain you a slightly cleaner output at higher voltage levels, but at the output levels needed for your external amp to gain full power (1.25V) it wouldn't make any difference. The 4700 has measured as clean as the Marantz pre-pros at that output level. Using an external amp wouldn't be a particular benefit in terms of the crosstalk performance (i.e. channel separation), altho I suppose a poor amp could limit the pre-amp in that regard. As to clarity/general sound quality differences....no. I think you're doing fine as is. Just enjoy the music/movies....

 

[New_Guy]

Took receipt of a emotiva bas-x A6 today, which allowed me to go full pre-amp mode on the Denon x4700h (A3 powers front stage, A6 powers surround + 4 Atmos channels. Arendal 1961 bed including both subs (1s), RSL in-ceiling for Atmos).

I’m not sure how to articulate it, without sounding cliche, also totally plausible it’s 100% placebo, BUT: my system does seem to sound clearer, and larger/deeper/wider (idk).

I want to A/B with the anthem AVM70, cuz I’m an idiot, who is far too curious, and apparently willing to set himself up for silly/ expensive decisions (the AVM70 is arriving this weekend)...

But honestly, at this point, I think the A/B is a waste of time, current configuration seems real legit.

As is, it’s wholeheartedly fulfilling, immersive, and pretty awe-some.

This HAS to be the point of diminishing returns, surely, I don’t see the anthem (or anything), sounding 4k$ “better”.

I’ll touch base later….

 

[lovinthehd]

Since those BasX amps are closer in capability to the avr's onboard ones, hard to know what you're hearing, altho imagination could well have a lot to do with it. How did you do an A/B with another avr/pre-pro, tho? That's not a particularly easy thing to setup properly. I'd simply not worry about the electronics so much and concentrate on speakers/subs in terms of placement/integration.....

 

[New_Guy]

Yea, I’m not sure how to articulate what I feel like I was hearing… just seemed, slightly more open? I don’t know.

I haven’t done an A/B yet, the AVM70 arrives this weekend.

My setup here is hardly scientific (real home), and I certainly don’t have any fancy gear allow instantaneous level matched switching nor ability to do so blindly….
Just plan to: Power up both sources, play A ref scene many many more times to try and acclimate as best as possible, then switch my source (Denon<->Anthem).

I do feel I must be at the threshold of diminishing returns for a normal setup though. After running full pre-amp mode, I’m already fairly certain I won’t be keeping the Anthem (even tho I haven’t heard it yet). It’s 2x the cost, and my room isn’t perfect…
I’ll try to give it a fair shot though, and it’ll be fun/interesting to compare room correction results/ sound profile differences here in my home in the real world

 

[PENG]

Yea, I’m not sure how to articulate what I feel like I was hearing… just seemed, slightly more open? I don’t know.

I haven’t done an A/B yet, the AVM70 arrives this weekend.

My setup here is hardly scientific (real home), and I certainly don’t have any fancy gear allow instantaneous level matched switching nor ability to do so blindly….
Just plan to: Power up both sources, play A ref scene many many more times to try and acclimate as best as possible, then switch my source (Denon<->Anthem).

I do feel I must be at the threshold of diminishing returns for a normal setup though. After running full pre-amp mode, I’m already fairly certain I won’t be keeping the Anthem (even tho I haven’t heard it yet). It’s 2x the cost, and my room isn’t perfect…
I’ll try to give it a fair shot though, and it’ll be fun/interesting to compare room correction results/ sound profile differences here in my home in the real world

In non preamp mode, your X4700H is capable of driving your Emo amps to clipping badly and destroy your speakers. At just 1.4 V, the pre out will be able to drive the Emo amp to output almost 400 W into those 4 ohm speakers, and at 1.4 to 1.5 V, pre out's distortion level will be the same as whether you are using preamp mode or not, that are just fact.

I think deep down you know what you had before (the A3) was good enough. What you are hearing now should be virtually identical, compared to the A6 using preamp mode, unless you are listening to very loud level for a certain kind of music. Even then, the difference in power output level under the so called all channel driven conditions are negligible in dB, as 2X the output give you only 3 dB difference in sound pressure level.

Placebo effect is all it is at play here. If within the return window I would return the A6 and saving the money for something more meaningful (in terms of sound quality). If you feel good about using preamp mode then so be it, but given the facts (see graph below) and figures there will no difference whatsoever given what you have.

Above are just my opinions, that you are welcome to ignore, below are sort of an objective assessment based on facts and figures (or the "scientific" way as you put it):

As HD pointed out before, preamp mode only gives you "cleaner" signal at higher output level that you likely would never reach, and the less "clean" pre out signal even when NOT in preamp mode is still at the very low 0.018% THD at 2 V, based on bench test.

At 2 V, your Emotiva amp would be driven to about 400 W into 8 ohms, or 800 W into 4 ohms!! Your 4 ohm rated speakers probably could handle about 250 to 500 W maximum.

Denon AVR-X4700 AVR Review (Updated) | Audio Science Review (ASR) Forum

See that at up to about 1.4 V, preamp mode (blue and red) and normal mode (dark and light green) had virtually identical distortion plus noise.

At 1.1V, you get 101 dB SINAD, that's 0.00089% THD+N, and the Emotiva A3 would have been driven to about 240 W into your 4 ohm speakers!!

I am just giving you the facts to consider. You hear what you hear, though without doing a truly controlled AB comparison it is hard to know if you are one who is not affected by Placebo and/or expectation bias.

 

[lovinthehd]

Yea, I’m not sure how to articulate what I feel like I was hearing… just seemed, slightly more open? I don’t know.

I haven’t done an A/B yet, the AVM70 arrives this weekend.

My setup here is hardly scientific (real home), and I certainly don’t have any fancy gear allow instantaneous level matched switching nor ability to do so blindly….
Just plan to: Power up both sources, play A ref scene many many more times to try and acclimate as best as possible, then switch my source (Denon<->Anthem).

I do feel I must be at the threshold of diminishing returns for a normal setup though. After running full pre-amp mode, I’m already fairly certain I won’t be keeping the Anthem (even tho I haven’t heard it yet). It’s 2x the cost, and my room isn’t perfect…
I’ll try to give it a fair shot though, and it’ll be fun/interesting to compare room correction results/ sound profile differences here in my home in the real world

Sometimes it's just that "new stuff" thing....hard to know....did you run setup/Audyssey again to accommodate the new amp? I'd take the opportunity to compare since you've already got it setup (or would that get in the way of the return?). It'll be a challenge to level match for that comparo, tho, especially if you are outside of direct mode type setup and using the REQ programs....

 

[New_Guy]

Thanks for the detailed response, and data!
Yea, admittedly, may very well just be placebo.
Also, I had to rerun room correction after adding the A6 to the show, and turning pre-amp mode on (since with the addition of the A6, all 9 channels are driven by external amps enabling the option of pre-amp mode)…. This alone would be a potential factor in delta of perceived sound quality.
Maybe I’m not reading the data product you provided correctly, but doesn’t it imply:
In pre-amp mode, SINAD integrity is maintained through very high levels, where as if the amps are on clipping ensues @ ~1.4V (I imagine that translates to very high volume, how high, 89db or whatever the amp is rated at?)…
And good point, performance is matched up to 1.4V.

So, basically pre-amp mode just kind of provides some signal integrity protection all the way through the volume spectrum?
… which likely will not matter unless I’m pushing things hard?
Are there other benefits of using pre-amp mode w/ external applications, aside from noise reduction in the signal at high volumes, or ensuring adequate power (all channels driven), or allowing an upgrade path to pre-pro?…
better processing as available power isn’t utilized by amps, idk anything?…

QUESTION:
I’m unsure how this works… what’s the translation for or implications of input sensitivity (on an amp) when comparing 8 ohm vs 4 ohm load ratings…
Is the sensitivity satisfaction voltage doubled (like power @4ohms, when compared to 8), or halved?

 

[New_Guy]

Anyway… Yes my system WAS fine without the A6, I cannot argue that.
I’m very fortunate to have such cool toys for sure. This setup is pretty amazing.

Not entirely sure what I’m after, aside from something that makes me smile when I sit down to enjoy.

I enjoy the hobby of it, and am endlessly curious.

 

[lovinthehd]

Anyway… Yes my system WAS fine without the A6, I cannot argue that.
I’m very fortunate to have such cool toys for sure. This setup is pretty amazing.

Not entirely sure what I’m after, aside from something that makes me smile when I sit down to enjoy.

I enjoy the hobby of it, and am endlessly curious.

Probably just a bit of a case of upgraditis?

 

[New_Guy]

Haha, this guy knows!

 

[lovinthehd]

Haha, this guy knows!

It's not like you're the only one....but after several avrs (and using four currently) and power amps mostly I don't even use the power amps except in my biggest room where I might play the loudest....and even then they're really not necessary, altho perhaps a bit of an advantage when I really crank it. I tend to use more powerful amps (mine range from 250 to 450 wpc) than the BasX stuff, too. I'd stick with what you've got at this point and only make a change if you run into issues/problems....

ps have you used this to help estimate your needs? http://myhometheater.homestead.com/splcalculator.html

 

[PENG]

Also, I had to rerun room correction after adding the A6 to the show, and turning pre-amp mode on (since with the addition of the A6, all 9 channels are driven by external amps enabling the option of pre-amp mode)…. This alone would be a potential factor in delta of perceived sound quality.

First of all, there is no need to re-run Audyssey just because you start using the A6 because the A6 has the same gain as the Denon's internal power amps. Even if you use an ext. amp with different gain, you could have just use a spl meter such as the popular Radio Shack's meter to level match the channels manually using the level trim settings.

Secondly, as you stated, "This alone would be a potential factor in delta of perceived sound quality."

"potential" is the key word here, in your application you have no chance to realize such potential advantage because the Denon preamp in non preamp mode will not even get close to 1.4 V based on the information you have provided so far. Even if you do push the Denon to output to as high as 2 V, your preamp output will still be able to maintain better than 70 dB SINAD. Can you really hear any distortions at -70 dB level when your room's noise level is likely in the range of 20 to 30 dB when nothing is on? I know I can't. So the advantage of the so called "purer" pre out signal in preamp mode is really academic.

Maybe I’m not reading the data product you provided correctly, but doesn’t it imply:
In pre-amp mode, SINAD integrity is maintained through very high levels, where as if the amps are on clipping ensues @ ~1.4V (I imagine that translates to very high volume, how high, 89db or whatever the amp is rated at?)…
And good point, performance is matched up to 1.4V.

May or may not be considered "very high levels" depending on how one defines very high. Denon AVR's 95 to 100 dB SINAD at 2 V, measured with a 1 kHz signal is among the best of all AVRs and AVPs tested so far by ASR or Audioholics.

On the other hand, as you noted, up to 1.4 V, there were no differences between the regular mode and preamp mode anyway, so in your applications you won't notice any difference even if you have the golden ears!

So, basically pre-amp mode just kind of provides some signal integrity protection all the way through the volume spectrum?

Again, that depends on your usage, in your case, even in non preamp mode, "signal integrity" will be maintained all the way through your "volume spectrum", assuming you mean from your minimum to maximum volume when listening to music or movies.

… which likely will not matter unless I’m pushing things hard?

Actually, it will not matter even you push things hard, because your AVR can drive the Emotiva A6 to well pass its clipping point without even reaching higher than 1.2 V. At that level, the AVR's SINAD will be at >100 dB SINAD, or less than 0.001% while your Emo power amp will be clipping, with distortions approaching 1%.

Are there other benefits of using pre-amp mode w/ external applications, aside from noise reduction in the signal at high volumes, or ensuring adequate power (all channels driven), or allowing an upgrade path to pre-pro?…
better processing as available power isn’t utilized by amps, idk anything?…

No, not in your case, but yes, if your power amp is capable of at least around 300 W 8 ohm and you actually need such higher output because of your speakers and listening habits. Otherwise, preamp mode will help the AVR run cooler and consumed a little less power, that's about it.

And also no, upgrade path to prepro in terms of better audio performance is really narrow because you would have to spend a lot more money and there aren't too many prepro that can out perform those Denon AVRs. If you compare yours with the Marantz AV7705 prepro, the Denon measured much better, the more expensive Marantz AV8805 did do better but they still measured worse than the Denon AVRs.

QUESTION:
I’m unsure how this works… what’s the translation for or implications of input sensitivity (on an amp) when comparing 8 ohm vs 4 ohm load ratings…
Is the sensitivity satisfaction voltage doubled (like power @4ohms, when compared to 8), or halved?

That's a good question and you will like the answer since you have 4 ohm speakers lol..

Your A6's input sensitivity is 1.2 V, that means to drive it to its rated 120 W it need 1.2 V input, that is 1.2 V pre out voltage.

Gain and input sensitivity specs are directly related. By calculations, 1.2 V, with 29 dB gain, the A6 should output 143 W, at that level the A6 will be clipping, likely with THD higher than 1 % already. So your AVR's pre out is not the issue, the Emotiva A6 is and that's why I suggested you return it.

The A3 actually is more powerful (though marginally) than you AVR's internal power amps but the A6 is probably a little weaker.

Measurements of those Emotiva Bass X amps were worse than Denon AVRs, hopefully the newer A series could do better but I doubt it.

Take a look for yourself:

Emotiva BasX A-500 5-ch Amplifier Review | Audio Science Review (ASR) Forum

Next time your upgraditis gets to you, arm yourself with the following table so you can choose your power amp with "gain matching" taken into consideration:

Power into 8 ohms vs pre out vs gain
Preout (V)/Gain (dB)	23	24	25	26​	27​	28​	29​	30​	31​	32​
1.00	25	31	40	50​	63​	79​	99​	125​	157​	198​
1.10	30	38	48	60​	76​	95​	120​	151​	190​	240​
1.20	36	45	57	72​	90​	114​	143​	180​	227​	285​
1.30	42	53	67	84​	106​	133​	168​	211​	266​	335​
1.40	49	62	77	98​	123​	155​	195​	245​	308​	388​
1.50	56	71	89	112​	141​	177​	223​	281​	354​	446​
1.60	64	80	101	127​	160​	202​	254​	320​	403​	507​
1.70	72	91	114	144​	181​	228​	287​	361​	455​	573​
1.80	81	102	128	161​	203​	256​	322​	405​	510​	642​
1.90	90	113	143	180​	226​	285​	358​	451​	568​	715​
2.00	100	126	158	199​	251​	315​	397​	500​	629​	792​
2.10	110	138	174	219​	276​	348​	438​	551​	694​	874​
2.20	121	152	191	241​	303​	382​	481​	605​	762​	959​
2.30	132	166	209	263​	331​	417​	525​	661​	832​	1048​
2.40	144	181	228	287​	361​	454​	572​	720​	906​	1141​
2.50	156	196	247	311​	392​	493​	621​	781​	984​	1238​

 

[New_Guy]

So, the gain structure on the AVM70 it would cause what… double the clipping for emotiva’s?

So, how do these amps protect themselves? I have a feeling a very small percentage of consumers are spending time aligning gain structures between components…

Anthem AVM70 Review (AV Processor)

This is a review and detailed measurements of the Anthem AVM70. It was sent to me by the company for review and costs US $3799. The AVM70 has a very modern and attractive front panel and display: Company takes full use of the large display as you see with nice icons. Importantly, the...

www.audiosciencereview.com

 

[New_Guy]

Also, what’s the consensus on Denon processing?
Clearly dynamic EQ and dynamic volume are playing all sorts of tricks. I imagine is an issue of preference… but is there any data on what’s “better”…. These processing tricks, or pure audio calibrated well and listened to on a true red scale (apposed to EQ’d up with audyessey tricks)…

 

[lovinthehd]

Also, what’s the consensus on Denon processing?
Clearly dynamic EQ and dynamic volume are playing all sorts of tricks. I imagine is an issue of preference… but is there any data on what’s “better”…. These processing tricks, or pure audio calibrated well and listened to on a true red scale (apposed to EQ’d up with audyessey tricks)…

Tricks? Better? They are simply tools you can use, whether you like them or not is up to you. Dynamic EQ is just a loudness contour to "fix" the way we hear certain frequencies at lower than reference volume, and is scaled with the master volume setting. Dynamic Volume is just a compression routine to level out the volume, particularly for playback at lower volumes (like at night to avoid bothering others) by boosting the lower volume content and reducing the higher volume content and evening it out (somewhat like the loudness wars compression). Whether you use them or not is a preference....personally I use DynEQ at lower volumes, but don't use DynamicVol at all....both utilize the basic general eq provided by Audyssey, so it's not opposed but rather in conjunction with.

ps Fixed as had mislabeled Dynamic EQ as Volume.....

 

[William Lemmerhirt]

Also, what’s the consensus on Denon processing?
Clearly dynamic EQ and dynamic volume are playing all sorts of tricks. I imagine is an issue of preference… but is there any data on what’s “better”…. These processing tricks, or pure audio calibrated well and listened to on a true red scale (apposed to EQ’d up with audyessey tricks)…

As HD said, Deq is a loudness contour that address how we hear at lower volumes. It’s effects get lessened the closer you get to reference(mv-0). It looks like this.

It mainly focuses on bass, but does boost the treble as well. It also boosts the surround levels, and rear height/too levels too. I don’t use deq as I use a minidsp to set a house curve and I HATE that it boosts surround and rear tops. Ymmv.
I also dislike dynamic volume and have no use or need for it. Tricks? Not necessarily, but they are very powerful.

 

[New_Guy]

Very cool.
Thank you both!
I’m currently auditioning the Anthem AVM70.
It doesn’t have the same EQs as my x4700h, aside from something called “Dolby post processing” there’s a couple presets (movie, music etc), to me they seem like an adaptation of dynamic volume (medium setting maybe) some sort of compression narrowing the delta between loud n quite. After a lot of listening, when I found and turned it on, I immediately turned it off, I really don’t care for it.

Over the last day I’ve been using none of it (no EQ, no processing, just as is in whatever Dolby format), calibrated it and went.

I need to go back n hook up the Denon, run a fresh cal and turn off all EQing, and listen to it raw as decoded.

… I’m not sure I can justify 2x cost (more than that if I wait for the latest model w/Dirac that started shipping, man I’m curious about Dirac).

That said, this really does sound really nice. I’m now a fan of ARC genesis (first exposure), seems to have done an incredible job w/ just blending all the speakers in my room.

Really well balanced, kind of subtle in a weird way, but it seems to sound really nice… quite is dead silent, presence/ambience are there and really sharp, nothing overpowers anything else, bass is was actually more subdued than Audessey after the first cal (which is kind of wild, audyessey really pulls back on base, like 3-4db at least in my experience).
So I applied a house curve/ boosted the bass a little in ARC, and tuned even more after more listening session (ARC allows for a good bit od tinkering). I like what I’m hearing. Incredible “intelligibility” I feel like a poser youtube guy saying that, but I’m not entirely sure how else to articulate it (I think this is the best my center has ever sounded, at low or high volume). It jus feels well balanced, all of it I like it.

Maybe it’s ARC, maybe it’s DACs, maybe a butterfly flapped its wings in Cambodia…Placebo? Real? I don’t know mannnn. But it seems nice to me.

My 4700 is good (maybe great), and gets loud/ immersive for absolutely certain.
I really need to go run a fresh cal, disable all EQ, tweak tune to my preferred sound, and really spend some time comparing.

The “upgrade”-itis may have hit, but this anthem is a lot of money (to me).

 

[HackMan55]

Very cool.
Thank you both!
I’m currently auditioning the Anthem AVM70.
It doesn’t have the same EQs as my x4700h, aside from something called “Dolby post processing” there’s a couple presets (movie, music etc), to me they seem like an adaptation of dynamic volume (medium setting maybe) some sort of compression narrowing the delta between loud n quite. After a lot of listening, when I found and turned it on, I immediately turned it off, I really don’t care for it.

Over the last day I’ve been using none of it (no EQ, no processing, just as is in whatever Dolby format), calibrated it and went.

I need to go back n hook up the Denon, run a fresh cal and turn off all EQing, and listen to it raw as decoded.

… I’m not sure I can justify 2x cost (more than that if I wait for the latest model w/Dirac that started shipping, man I’m curious about Dirac).

That said, this really does sound really nice. I’m now a fan of ARC genesis (first exposure), seems to have done an incredible job w/ just blending all the speakers in my room.

Really well balanced, kind of subtle in a weird way, but it seems to sound really nice… quite is dead silent, presence/ambience are there and really sharp, nothing overpowers anything else, bass is was actually more subdued than Audessey after the first cal (which is kind of wild, audyessey really pulls back on base, like 3-4db at least in my experience).
So I applied a house curve/ boosted the bass a little in ARC, and tuned even more after more listening session (ARC allows for a good bit od tinkering). I like what I’m hearing. Incredible “intelligibility” I feel like a poser youtube guy saying that, but I’m not entirely sure how else to articulate it (I think this is the best my center has ever sounded, at low or high volume). It jus feels well balanced, all of it I like it.

Maybe it’s ARC, maybe it’s DACs, maybe a butterfly flapped its wings in Cambodia…Placebo? Real? I don’t know mannnn. But it seems nice to me.

My 4700 is good (maybe great), and gets loud/ immersive for absolutely certain.
I really need to go run a fresh cal, disable all EQ, tweak tune to my preferred sound, and really spend some time comparing.

The “upgrade”-itis may have hit, but this anthem is a lot of money (to me).

Dude, I accidentally gave you a thumbs down. Sorry about that.

I think it's awesome you're digging your setup.

 

[New_Guy]

Lol all good man, no worries at all.