Question about upgrading sound from AVR

[bgk84]

Hello everyone, this is my first post here and I found this forum to be most knowledgeable I thought it best to post my question here. It's a bit of long question so hopefully you can bear with me.

My aim/story:
I recently "upgraded" from my Sonos Amp to a Marantz Cinema 70s as I thought this to be most flexible receiver in terms of upgrading. Along with both these systems I'm using the B&W 707 S3 I also happen to own KEF LS50 Meta's. Now I'm quite happy with the Marantz performing its AV duties. But recently I thought of testing the KEF LS50 and b&w head to head I initially did this by connecting both speakers to either the Marantz and or Sonos Amp I initially thought that there was huge difference soundstage when comparing the B&W to the LS50 meta's but to my surprise the speakers became much more comparable when I connected to the Sonos Amp. I loved the sound of the Sonos so much more on both speakers for its spacious and being able to throw different instruments in different parts of the room (I did like the B&W even a bit more in this regard though). I thought this might be caused then by the Audyssey room correction so I tried listening in Pure direct but even then though I will admit the soundstage became a tiny bit more lose the, to me of the Sonos Amp was still so much better. Now to further clarify I also have a Sonos port connected to the Marantz Cinema 70s so I expect the DAC and audio science in the Sonos Amp and Sonos port to be somewhat similar... leaving the obvious difference in the Marantz when it comes the that's being produced. So now I'm hoping to now get a somewhat similar sound out of the Marantz with perhaps the help of an external amp, obviously connecting the Marantz through pre-outs to the Sonos amp would never work well because of latency in the first place.

Question:
Here is where things start to get really murky for me. I know that there are some receivers nowadays which have the now sometimes loosely called HT bypass function and I know there's a website of amp's that support this feature. But I'm wondering how special HT bypass and is it really much better/different then a separate power power amp and also would a more smaller simple amp like topping produce similar results. Honestly I really don't want another huge device just to get better sound from my speakers but I honestly don't know what to expect. Another thing is that I know for example the Rotel A11 has an option for fixed volume input which essentially allows for something like HT-bypass it's just not known under the same name. As you might already be able to tell I'm very new to this so I'm not really sure what to look for. So far there are a couple of things I've considered as an upgrade:

- Get an amp with HT-bypass feature (not preferred due to size)
- Get a small amp like a Topping, Aiyima, Arylic etc
- Get a new AVR
- The most "barbaric solution" get a speaker switch, I sort of dislike this option because as far as I can tell these all don't have remote controls, I suppose to not interfere with the signals passing through the switch

I'm hoping you guys can maybe shine a light on this, or maybe once went down a similar rabbit hole. Any and all input/suggestions will be very appreciated

 

[antcollinet]

So first - the obligatory.

Well designed amps running within their limits will not have a significant sound. It is extremely unlikely what you are hearing as difference is due to the characteristics of the amp stage of the two devices.

It could be the DSP of the AVR - but you said you did the comparison in pure direct and still heard a difference. (If I understand correctly this is the same as HT bypass you mention - all HT bypass does, is bypass all the DSP - like pure direct)

So - I'm going to guess you've not accurately level matched the two amps. If they are not level matched accurately (to 0.1dB using a volt meter) then it is quite likely a small level difference in levels - even that can't be perceived as a volume difference - will be perceived as a quality difference.

So before you go throwing money at the "problem" it would be wise to be sure there is a problem to solve. To do this you'll need to test level matched and ... yes ... blind. Because even if you've level matched accurately, you, just like everyone else, can be subject to subconscious cognitive bias that can cause you to hear a difference even when there is no difference in the sound waves.

An alternative is to just use the AVR for a few weeks, or months. Once you get used to that being what you listen to - and it is just normal - you may find those perceived differences disappear.

 

[bgk84]

Thanks for your reply. This is sort of the answer I was hoping to find because I also had doubts whether an amp would make that much difference. But you do hear reviewers saying stuff like for speaker xyz you'd need at least a decent amp to get its full potential. And to my own surprise this was one of the moments I really found the was a difference. I did test rather loudly. Of course on paper the Sonos amp is 120 watt amp per channel whereas AVR is always somewhat less clear (claimed 50 watts, perhaps a bit too low for these type of speakers?). Those kind of statements made me wonder as to how much difference it might make other then of course when listening on different volume levels I suppose I'll have to give it another shot.

Of course I can't say for sure if the Sonos port or AMP would give a similar sound or if it would somehow render sound differently, by ear I really heard a clear distinction where the sound of the Marantz sort of send all the sound straight to my ears whereas the Sonos amp would let sounds dance throughout the room a bit more, either way I'll test again later and follow up

 

[antcollinet]

Thanks for your reply. This is sort of the answer I was hoping to find because I also had doubts whether an amp would make that much difference. But you do hear reviewers saying stuff like for speaker xyz you'd need at least a decent amp to get its full potential. And to my own surprise this was one of the moments I really found the was a difference. I did test rather loudly. Of course on paper the Sonos amp is 120 watt amp per channel whereas AVR is always somewhat less clear (claimed 50 watts, perhaps a bit too low for these type of speakers?). Those kind of statements made me wonder as to how much difference it might make other then of course when listening on different volume levels I suppose I'll have to give it another shot.

Of course I can't say for sure if the Sonos port or AMP would give a similar sound or if it would somehow render sound differently, by ear I really heard a clear distinction where the sound of the Marantz sort of send all the sound straight to my ears whereas the Sonos amp would let sounds dance throughout the room a bit more, either way I'll test again later and follow up

Also bear in mind - an amp cannot influence the stereo image. That is created in our brain from cues in the music, but also the way the speakers interact with the room (reflections etc). Speakers and positioning (of both speakers and listener) and room can influence image. The amp cannot.

 

[Chrispy]

Your avr has pre-outs, to me makes more sense to simply use an external amp if you want more power. That is a fairly lightweight avr as far as amp section goes (and it is 50wpc at 8 ohm, Sonos is 120wpc at 8 ohm)and traditionally B&Ws can be a bit demanding of an amp in terms of impedance/phase angle IIRC. The additional power of the Sonos could have been an advantage in your comparison, but it is maybe a 4 dB advantage....but as was mentioned hard to know what you did about level matching.

 

[pogo]

Get a new AVR

That would be my preferred solution. Take a NAD T778 and it should sound the way you want it to sound.
The Marantz cannot drive such loads properly, see also here as an example the KEF (EPDR, ...), which requires a stable power supply unit: Link

 

[antcollinet]

The Marantz cannot drive such loads properly,

Sorry - that is nonsense.

As long as OP is able to get sufficient volume without driving the amp into clipping (and that *is* audible) then the marantz can drive those speakers fine.

Adding a sub will help here too - and will result in better sound than that NAD you've mentioned without a sub. Oh, and the Nad is 4x the cost of the Marantz.

 

[pogo]

What bgk84 hears is already the distortion from the Marantz. Marantz is known for the fact that some of their class a/b amplifiers are not very stable under load, see also here on page 52: Link
The problems are also above the sub range and only a different amplifier (AVR or amp on the pre-outs) will help here.
Unfortunately, too few reactive load tests are carried out at ASR or a power cube is made available.

 

[antcollinet]

What bgk84 hears is already the distortion from the Marantz.

That is an impressive piece of remote diagnosis

Or is it just an assfact?

(in other words, what evidence do you have for this remarkable assertion?)

 

[-Matt-]

It could be the DSP of the AVR - but you said you did the comparison in pure direct and still heard a difference. (If I understand correctly this is the same as HT bypass you mention - all HT bypass does, is bypass all the DSP - like pure direct)

I don't think that is what HT bypass is. My understanding of HT bypass is the following...

It is typically a feature of INTEGRATED amplifiers only. Integrated amps have both a preamp section (for volume control) and a power amp section. When you connect CD players etc to the normal inputs on the integrated amp you can use its volume knob. When you connect your AVR to the HT bypass input, it BYPASSES (and therefore disables) the integrated amp's preamp section (and tone controls, as mentioned). So the integrated amp will act as a power amp only, and volume control will be done by the AVR. (The integrated amp's volume knob won't work for that input - it will just be full volume all the time).

There isn't anything magic or better about HT bypass (this is a red herring). If you feel the need to add external amplification you'd probably be better off using power amps (with all sources connected to the AVR).

The use case for HT bypass is if you want, for example your cd player, connected to the integrated amp only for stereo (without Audyssey features). This is fairly pointless as it is effectively the same as using pure direct on the AVR.


Regarding the difference in sound between Sonos and Marantz amplification...

Whilst we can be pretty certain that Marantz in pure direct has a flat frequency response, I wouldn't be so sure about the Sonos. It might well be boosting bass, for example, which the op might prefer. We'd need to see measurements for that model to know for sure. Of course if the Marantz were configured for a similar house curve the percieved preference for the Sonos would likely go away.

I'd suggest the op not to use pure direct on the Marantz as this disables many of the good features of Audyssey. Try again with features such as Dynamic EQ enabled (try out the different reference level offsets). I think you will then find the Marantz more engaging.

 

[pogo]

Also bear in mind - an amp cannot influence the stereo image. That is created in our brain from cues in the music, but also the way the speakers interact with the room (reflections etc). Speakers and positioning (of both speakers and listener) and room can influence image. The amp cannot.

The Marantz is not an ideal amplifier and will be less and less able to reproduce a stable stereo image on such loads (impedance/phase) with increasing volume.

 

[-Matt-]

Is this the Sonos amp in question?
https://www.audiosciencereview.com/...ds/review-and-measurements-of-sonos-amp.6957/

If you are using the line in it will be adding a lot of noise, though questionable whether this will be audiable.

I can't find measurements for the Marantz Cinema 70 but there are some for the Cinema 50 here:
https://www.audiosciencereview.com/forum/index.php?threads/marantz-cinema-50-avr-review.40605/

Comparing the dashoards:

Sonos (via line in):

Marantz:

Not a fair comparison as the C50 (110W) is more powerful than the C70 (50W) but it looks as though we can expect the Marantz be much cleaner than the Sonos (90dB vs 70dB SINAD).

Note: The measurements were carried out by different reviewers, so I can't be 100% sure that all test settings were identical.

 

[pogo]

we can expect the Marantz be much cleaner than the Sonos

This is a good example of how reality is different with a real load (assuming C50/C70 do not differ significantly). A purely ohmic and static test load has nothing to do with real world behaviour. Here we are only looking at one operating point!

 

[amadeogt]

Marantz only rates the Cinema 70's power output with 8 and 6 ohm speakers. It doesn't list its output with a 4 ohm load - probably because the amp struggles under that load.

The B&W 707 S3 specs say it is nominal 8 ohm, but has a minimum 4 ohm load. Also, its sensitivity is not the highest (84 dB). You need a certain amount of current to drive it properly.

Maybe this means the Cinema 70 is not up to the job. The Sonos, on the other hand, has no issues with 4 ohm (being a Class D amp).

If I were you, I would try a cheap Class D amp, like the Aiyima A07 ($ 70, good performance on the ASR tests), connected to the Cinema 70's pre-outs. You might be surprised with the result. It made a world of difference on my Marantz SR5005 AVR (that has weakish onboard amps, just like the Cinema 70), driving a pair of 4 ohm Monitor Audio RX8 speakers.

 

[pogo]

With these speakers, an external Hypex Class-D would make more sense in order to show the speaker's potential.

 

[-Matt-]

FYI those dashboards were all measured with a 4 Ohm load (although fixed).

I'd better leave it to @amirm to explain whether testing with a static load is sufficient; but I invite @pogo to explain further the possible deficiencies and to suggest a practical alternative test protocol.

 

[pogo]

Again #8:
Unfortunately, too few reactive load tests are carried out at ASR or a power cube is made available.

That would be a start.

 

[-Matt-]

What bgk84 hears is already the distortion from the Marantz.

Occam's razor would suggest ruling out a simple level mismatch first.

By the way @amirm already measures at both 4 and 8 Ohms. Those power cube measurements linked in #8 also seem to be just a sequence of measurements with different static loads.

 

[pogo]

Yes, but also with phase shifts.

 

[bgk84]

First of all thanks to everyone for weighing in, based on all the feedback I have done some more testing. Unfortunately I don't have mics or any good equipment to do a proper measuring however. I have found something interesting. This time I tested purely using the the B&W 707 speakers as I still find these to be more spacious sounding regardless of the source.

In contrast to my previous testing I didn't play back the track directly through the Sonos app but used Roon and used airplay protocol for playing back the same track to both the Sonos amp and Marantz (cutting out the Sonos port). To my surprise I started to find both amp's starting to sound much more similar with perhaps the Sonos still having a bit more full bodied sound and perhaps a bit more forward sounding but overall much more evenly matched. I later also tried airplaying to the Sonos port and found the sound to be less contrasting then before but perhaps still sounding a bit better when played directly through airplay to the Marantz. I'm not sure what made the difference perhaps the way Sonos handles tracks when played directly from source rather then receiving an airplay stream are a bit different either way I'm more convinced that the amp's are fine though I did notice I had to set the volume level much higher on the Marantz in Roon to get a similar sound that I got from the Sonos amp with a lower volume setting but that only makes sense so I might still go for a tiny class D amp as suggested to if it makes any further difference (is the difference in Ohm load audible?).

Lastly a bit off topic but am I crazy for liking the B&W much more? I've seen the KEF LS50 Meta almost universally praised as great speakers whereas B&W speakers gather quite a lot of criticism and while I have to admit that when I play back vinyl there is definitely a hissing issue (sibilance) they do well with most others playback situations (especially clarity with vocal and dialogue is amazing). If the sound wasn't that bright I'd say there's no contest here, but I think perhaps that may be fixed with a phono pre amp or tone controls?

also last edit: yes it's indeed the same amp
https://www.audiosciencereview.com/...ds/review-and-measurements-of-sonos-amp.6957/