Marantz AV7705 Home Theater Processor Review

[Matthew J Poes]

has marantz announced an 8k update to their processors? i know they announced their recievers but hopefully a 7705 update is coming soon?

Yes! And that’s all I can say.

but keep in mind that everything is being delayed by the effect of COVID-19 on manufacturing in China. Be it American made or chinese made, parts shortages and backlog are causing huge issues for everyone.

 

[dkmaier]

Thanks

 

[urfaust]

https://www.signiant.com/blog/see-8k-resolution-television/

"For a person with 20/20 vision, while sitting 10 feet away, one would need about a 75-inch display-diagonal for HD, 120-inch for 4K, and a whopping 280 inches for 8K to be able to distinguish the resolution!"

There are a lot of myths in the Video world too, and 8K is gonna be one of those in the upcoming years. It can have some merits in some very special cases, more computer related, because that statement is true but the worst part is that if you get an 8K set you ll have to be that much closer to distinguish the difference from 4K, than your eyes wont be able to see the whole picture...you would have to stand in front of the tv and moves you head like a silly dog, that's how useless 8K is in a Cinema context.
In general use of TVs, people tend to already sit too far, the equation is only going to get worse with 8K.

The real challenge of HC imo is rather to get better sources, they could be fine in higher res, 8k included, better bitrate,... but for TV sets, im already tired of hearing about 8K.

 

[LeeDeeCaa]

Good day Amirm.
I want say Thank You for your great job with AVRs reviews.
I was reading many of AVR reviews on this site.

And have one question.
Why You are testing the recevers with Pre-amp output level 2 Volts?

In the Receiver specifications:
for Denon/Marantz receivers (AVR-X3600H, AVC-X8500H Etc) "Reference level for Analog Outputs" is 1.2 Volts.
for Yamaha receivers (RX-A2080/A3080 Etc) "Rated Output Level / Output Impedance - PRE OUT" is 1.0 V/470 Ω
for Arcam receivers (AVR390 Etc) "Nominal output level" is 1V RMS, 560Ω.

In this review (Marantz AV7705), when You changed the Pre-amp OUT level from 4V (Vol=82) to 2.4V (Vol=77.5 (spec)), the amount of signal harmonics has decreased significantly, and SINAD changes from 75dB to 92dB (THD+N Ratio changes from 0.017 to 0.0024).

In the next Yours review (first review of Denon AVC-X4700) when is "SINAD vs Measured Level" measurements with Amps Vol=82.5dB and Vol=90dB, the SINAD level is "Better" when Vol=82.5dB (and maybe will be "Better" if Vol=79-80 dB).

Assumption - if you will test the amplifiers with an output signal (Pre-Out) equal to 1.2 volts (DENON / MARANZ) or 1.0V (Arcam/Yamaha), maybe then it is possible to improve the signal-to-noise ratio (SINAD ) and will reduced distortion (THD+N Ratio).

It was again in the Your test (AVC-X8500H Review), when You are tested "Zone 2 DAC Audio Performance" Vol=70dB. Maybe nose floor was little bit higher, but the second and etc harmonics was decreased significantly.

Maybe the preamplifiers in Receivers is "stressing" when they Output lever is higher of "nominal / reference" levels from manufactures?

Sorry for my English .

Thank You.
Dmitry.

 

[LeeDeeCaa]

Attached Your measurements, to visualize my words

 

[LeeDeeCaa]

And this from AVC-X4700H (first) Review

 

[peng]

And have one question.
Why You are testing the recevers with Pre-amp output level 2 Volts?

In this review (Marantz AV7705), when You changed the Pre-amp OUT level from 4V (Vol=82) to 2.4V (Vol=77.5 (spec)), the amount of signal harmonics has decreased significantly, and SINAD changes from 75dB to 92dB (THD+N Ratio changes from 0.017 to 0.0024).

Amir explained that more than once. He used 2 V in order for the users to have a wider selections of power amplifiers that may have gains from 26 to 32 dB, or even outside that range, and output power greater than 200 WPC that a lot of AVR users would like to use with their AVRs.

In the review of the Marantz AV7705, Amir used the balanced connections, so the 4 V would be equivalent to 2 V for the Denon reviews and the 2.4 V should be compared to the Denon review's 1.2 V. In other words, if Amir had used the unbalanced (RCA) connections in the review of the AV7705, he would have used 2 V and 1.2 V. So the AV7705's preamp output performance in SINAD was in fact significant worse than those Denon AVRs.

 

[LeeDeeCaa]

Amir explained that more than once. He used 2 V in order for the users to have a wider selections of power amplifiers that may have gains from 26 to 32 dB, or even outside that range, and output power greater than 200 WPC that a lot of AVR users would like to use with their AVRs.

In the review of the Marantz AV7705, Amir used the balanced connections, so the 4 V would be equivalent to 2 V for the Denon reviews and the 2.4 V should be compared to the Denon review's 1.2 V. In other words, if Amir had used the unbalanced (RCA) connections in the review of the AV7705, he would have used 2 V and 1.2 V. So the AV7705's preamp output performance in SINAD was in fact significant worse than those Denon AVRs.

Hi peng.
Now I understand what it was done for (RMS level = 4V on XLR PreOut). Unfortunately the measurements and ratings (TDH + noise and SINAD) are misleading. And they do not show (with average statistical use) the nominal values of TDH + noise and SINAD at reference (normal) levels at PreOut. Measurements at a higher output level (PreOut=4V not 2.4V) only show how the preamplifier behaves under stress. Accordingly, you get excessive distortion and SINAD.

Thank You.
Dmitry.

 

[LeeDeeCaa]

In my understanding, only after studying the measurements of "Power Versus Distortion @ 4 (8) Ohm Both Channels Driven" can you compare the receivers. There you can clearly see TDH + Noise Ratio (without additional distortions for supervoltage on PreOut).

 

[peng]

Hi peng.
Now I understand what it was done for (RMS level = 4V on XLR PreOut). Unfortunately the measurements and ratings (TDH + noise and SINAD) are misleading. And they do not show (with average statistical use) the nominal values of TDH + noise and SINAD at reference (normal) levels at PreOut. Measurements at a higher output level (PreOut=4V not 2.4V) only show how the preamplifier behaves under stress. Accordingly, you get excessive distortion and SINAD.
View attachment 77917
Thank You.
Dmitry.

That may be fair, for normal use 1.2 V, RCA and 2.4 V XLR are likely more representative for a lot of users, but I do think it is better to be sure that even at 2 V RCA and 4 V XLR SINAD remains high in case someone do listen loud and/or sit far away in a large room, have low impedance and/or low sensitivity large tower speakers. Also, don't forget some movies and even music could have maximum peaks of 20 dB or more, and that may require the pre-out to be capable of 2 V or higher, especially under the conditions I just mentioned.

Anyway, now that Amir has standardized on including the pre-out SINAD versus output graph, you can see the SINAD performance at any level from very low to 2 V. See below for an example, and note that if XLR (Denon AVRs do not have balanced I/Os) is used, the X-axis would then be from 0 to 4 V.

 

[LeeDeeCaa]

Thanks for the detailed explanation.

 

[Martin_320]

That may be fair, for normal use 1.2 V, RCA and 2.4 V XLR are likely more representative for a lot of users...

My AV7705 is feeding a Rotel RMB-1075 5ch power amp (unbalanced RCAs), and the the latter's officially stated spec for input impedance/sensitivity = 33 k Ohms/1.0 Volt.
Question: Does this mean that anything above 1 Volt from the Marantz input is enough to drive the amp to max output? (130 watts RMS per channel into 8 Ohm speakers) ?

 

[peng]

My AV7705 is feeding a Rotel RMB-1075 5ch power amp (unbalanced RCAs), and the the latter's officially stated spec for input impedance/sensitivity = 33 k Ohms/1.0 Volt.
Question: Does this mean that anything above 1 Volt from the Marantz input is enough to drive the amp to max output? (130 watts RMS per channel into 8 Ohm speakers) ?

Yes, if it says sensitivity is 1 V, it usually means it takes 1 V to drive it to its rated output. In this case it only take 1 V because the amp is only rated 120 W.

 

[Martin_320]

Yes, if it says sensitivity is 1 V, it usually means it takes 1 V to drive it to its rated output.

Thanks -- I feel better! -- So Amir's graphs are showing results that clearly don't reflect the real world -- they are so far off the scale from what normal people would use an AVP for (and way beyond what the downstream power amps can actually take at their inputs !). For what it's worth, '70' on the volume knob is as loud as I ever need to take the AV7705 / Rotel combo. Mostly I have the volume set at between 40 and 60.

 

[peng]

Thanks -- I feel better! -- So Amir's graphs are showing results that clearly don't reflect the real world -- they are so far off the scale from what normal people would use an AVP for. For what it's worth, '70' on the volume knob is as loud as I ever need to take it.

That is not always true, it really depends! Yes, you can say that in your case but that's because you don't need a lot of power obviously. As I mentioned before, there are others who may sit farther away from the speakers, have speakers that have low sensitivity and low impedance so they may need to pair their AV7705 with a much more powerful amp than yours. It get worse if the power amp of their choice happens to have a little lower gain such as 26 dB.

As an example, the very popular Monolith 200 WX5 amp's input sensitivity is 1.6 V, so if you have such an amp and want to take full advantage of its rated continuous output and dynamic output, then you may actually feel better if the AV7705 can output up to 2 V without much degradation in SINAD.

 

[Martin_320]

the very popular Monolith 200 WX5 amp's input sensitivity is 1.6 V, so if you have such an amp and want to take full advantage of its rated continuous output and dynamic output, then you may actually feel better if the AV7705 can output up to 2 V without much degradation in SINAD.

But here it's not really relevant how "farther away" one sits from the speakers, because Amir's measurements go electronically beyond even the worst-case scenario -- voltage wise -- for over-driving that amp -- ie greater than the 1.6V needed to thrash the Monolith. And in my case, 1Volt is enough to thrash the Rotel.

It would be good to see graphs for the up to 2V usable region, rather than going beyond it.

 

[hmt]

Another scenario are active speakers. You want to drive them with the highest possible input so you can turn their sensititvity down.

 

[peng]

But here it's not really relevant how "farther away" one sits from the speakers, because Amir's measurements go electronically beyond even the worst-case scenario -- voltage wise -- for over-driving that amp -- ie greater than the 1.6V needed to thrash the Monolith. And in my case, 1Volt is enough to thrash the Rotel.

As I said before, that is true in your case because your amp is only rated 120/130 W. I am just trying to explain to you why I think Amir is doing the right thing by testing the AV7705 at 4 V XLR instead of only 2.4 V XLR. Again, 2.4 V XLR for you is great, probably no need for more, but others may have very different requirements than yours, such as higher power amps and may have lower gains too so they may need much higher pre-out voltage than 1.2 V RCA/2.4 V XLR.

So it is relevant because how much power output you need for your power amplifier depends a lot on your sitting distance. Every time you double the distance you lose 6 dB of SPL so for the same SPL you will need 4X the power.

It also depends on the SPL you like, some people don't need more than 70 dB when watching even Star war kinds of movies, with peaks to 90 dB, while others, though I guess not too many, may prefer spl closer to reference level (85 dB/105 dB max. peak).

Below is just a numerical example, if you already know it then please ignore, I am doing it just in case..

Person A
Distance ..................................................................................................................................................... 2.5 meters
Sound pressure level required by the listener when watching movies............................... 76 dB/96 dB peak
Speaker sensitivity.................................................................................................................................... 87 dB/2.83V/1m
Speaker impedance.................................................................................................................................. 8 ohms
Room gain assumed................................................................................................................................. 3 dB


Amplifier power required will be......................................................................................................... 25 W to avoid or minimize clipping during the peak demands.

Person B
Distance......................................................................................................................................................... 4 meters
Sound pressure level required.............................................................................................................. 84 dB/104 dB peak
Speaker specs.............................................................................................................................................. Same as Person A's
Room gain assumed.................................................................................................................................. Same as Person A's

Amplifier power required will be.......................................................................................................... 400 W
Now assume Person B's 400 W rated power amp's gain is lower........................................... 28 dB gain, that is sensitivity about 2.25 V

Using the above examples, assuming amplifiers with gain of about 30 dB such as your Rotel, then Person A will only need about 0.5 V pre-out voltage to satisfy his 25 W requirement, that's of course without any headroom consideration.

Person B will need almost 2.25 V to drive the 400 W power amp that has lower gain, to its rated output. That's just an example with make up numbers, you can experiment with an online calculator to see how much distance, SPL and speaker's sensitivity impact on one's power amp requirement.

And remember, the higher the power amp output, all else being equal, the higher the pre-out voltage you are going to need from you pre-amplifier.

Link to an online calculator:
https://myhometheater.homestead.com/splcalculator.html

I hope this clears things up.

 

[Martin_320]

Sorry, it doesn't really clear things up.
I sit about 4.5m from my front L/R Tannoy floorstander & center speakers (and 3m from the surrounds), and if I had wanted more power I would have got the -1075's bigger brother -- the RMB-1095.
And to drive that to max power only needs 1.5Volts (for both XLR and RCA). Nowhere near even your lower figure of 2.25V
(You can verify the specs online).

So please tell me, what amp are you referring to that could possibly need 4+Volts applied to its input terminals?

 

[peng]

Sorry, it doesn't really clear things up.
I sit about 4.5m from my front L/R Tannoy floorstander & center speakers (and 3m from the surrounds), and if I had wanted more power I would have got the -1075's bigger brother -- the RMB-1095.
And to drive that to max power only needs 1.5Volts (for both XLR and RCA). Nowhere near even your lower figure of 2.25V
(You can verify the specs online).

So please tell me, what amp are you referring to that could possibly need 4+Volts applied to its input terminals?

I gave you the example already in post#238:

Person B
Distance......................................................................................................................................................... 4 meters
Sound pressure level required.............................................................................................................. 84 dB/104 dB peak
Speaker specs.............................................................................................................................................. Same as Person A's
Room gain assumed.................................................................................................................................. Same as Person A's

Amplifier power required will be.......................................................................................................... 400 W
Now assume Person B's 400 W rated power amp's gain is lower........................................... 28 dB gain, that is sensitivity about 2.25 V

There are many amplifiers that have gains at around 28 dB. ATI amps can be an example:
https://www.ati-amp.com/manuals/ATIpowerampspecs.pdf

You can see that 3 out of 8 of their power amps require 2 V or higher for them to reach their rated output. There are power amps that have even lower gains. That's based on unbalanced, for balanced it will be 4 V or higher.

Question, why you keep referring to your own scenario? As I mentioned more than once, you don't need 2 V RCA, 4V/XLR because you don't need much power. I only mentioned that some people who need more power will need higher pre-out voltage depending on their speaker's specifications, seating distance and spl (how loud they listen) requirements.

Okay you sit 4.5 meter from your front speakers but may be your Tannoy has high sensitivity and you don't listen to levels as loud as others.
So let me say this one more time, for you, 1.2 V is enough, may be more than enough, but for others they may need 2 V or even higher. And I am talking about RCA unbalanced, for XLR balanced, it would mean 2X the voltage, typically speaking as there are always exceptions depending on the design.