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Marantz AV8805A Review (AV Processor)

MacCali

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Yes that is specific to your avr, speakers and your listening habits (spl requirement and distance).
To be clear, like power amp output, it can also be said that for preamp output, the higher the better. It is however, important to realize if you don't ever tap into outputs (preamp and/or power amp), you won't benefit from it in terms of audible sound quality. I only ever used about 0.2 to 0.5 WPC average, or up to 50 W (8 ohm) for the 20 dB peaks in some contents I might play when listening to music in stereo, but the amps I use are rated between 50 (the weakest one) to 350 W (the strongest one), not counting the 5 W DIY amp. I have used all of them to drive my speakers and they all perform the same sonically speaking with the exception of the 5 W amp.



The answer to your question about preamp output (aka pre out) voltage requirement depends on at least (in case I forgot some) the following:
- you power amp input "sensitivity", or "gain"
- your speaker sensitivity 2.83 V/m is preferred, if given in W/m then you have to consider the impedance, example for 4 ohm speakers, at the same voltage the power will be 2 W, and for 6 ohm speaker it will be 1.33 W
- your spl requirement, this is important when you consider the fact that for every 3 dB increase, your power amp requirement will be doubled and your preamp output voltage will have to increase by square root 2, that is about 1.414 times.
- your listening distance from speakers. Without factoring room gain, every time you double the distance the spl at you listening position will be reduced by 6 dB.

Assuming you don't sit further than say 4 meters, in a medium to medium large room, you will not have to worry about the above if you stick with preamp output >2 Vrms and power amp output > 200 W. Again, generally the higher the better..., there are always exception to the rules such as for someone who has truly hard to drive speakers..

Lastly, you seem to always referenced to "input sensitivity", from your previous posts/questions but I am not sure if you understand fully the relationship between "input sensitivity" and "gain".

In my opinion, gain is preferred because it is easier to understand. It is the ratio of Output to Input, the only slight complication is that amplifier gain is more often expressed in dB that is based on the "log scaled". The formula to convert from Vout/Vin in multiples to dB is 20X log (Vout/Vin).
Example: Vout/Vin = 2 would be the same as Vout/Vin = 20Xlog2 = 6 dB

People sometimes get confused (or even misled by, due to misconception) by the input sensitivity specification when it simply says 1.2 V (just an example), without any details. That 1.2 V could be based on achieving the rated output that can be anything such as 75 W, 100 W, 500 W etc.., or it is stated for a reference output of say 100 W into 8 ohms, as is often the case for Parasound amps.

The other potential confusion is due to the use of "low" or "high". Example, people may say 1 V is low, versus 2 V, because they are talking about the value, yet 1 V is actually higher than 2 V if they truly refer to "sensitivity" of the amp. To me, it would be more correct, and hopefully more common too, for people to refer to the sensitivity of the power amp, literally, than to refer to the input voltage value, so the lower the input voltage value in the spec would (and should) mean the higher sensitivity the power amp is.

So my question to you: when you said "a higher input sensitivity amp", did you mean the input voltage value, or the sensitivity (literally..)of the power amp? lol..
Hmmmm I get what you are saying, I was asking in reference to your measurements. I was considering purchasing a used Anthem amplifier so I can then have access to use 7 channels.

It says 1.5v for full power with a 29 db gain, MCA 525 gen 1 which is 225 pc.

Since the volts, db, and wattage is different does this change your original computation.

Also just briefly, I have not been into any type of audio until the pandemic. I bought my 7013, my first amp/equipment in September 20’, and I did not purchase my speakers until Black Friday 2020 so basically started using what I had in December so it’s been roughly a year and a half which is about the the time I signed up to ASR.
 

peng

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Hmmmm I get what you are saying, I was asking in reference to your measurements. I was considering purchasing a used Anthem amplifier so I can then have access to use 7 channels.

It says 1.5v for full power with a 29 db gain, MCA 525 gen 1 which is 225 pc.

1.5 V input sensitivity for 225 W is practically the same as 29 dB gain.

Since the volts, db, and wattage is different does this change your original computation.

Absolutely, volts, dB does the same thing mathematically if you know the math and if the manufacture states both the volts and the output W like Anthem did.
Since the calculations I did for you based on the information you provided were also based on 29 dB so the required pre out voltage for your AVR will be the same if you go with the MCA525, as long as you don't need go exceed your power amp's rated output that is 120 W into 8 ohms for the Denon POA 8300.

You only need 1.5 V if you crank the volume up to the point the MCA 525 will output 225 W.

Also just briefly, I have not been into any type of audio until the pandemic. I bought my 7013, my first amp/equipment in September 20’, and I did not purchase my speakers until Black Friday 2020 so basically started using what I had in December so it’s been roughly a year and a half which is about the the time I signed up to ASR.

I understand you may not have a strong background in the EE theories and math needed to understand some of the audio specs. There has been many posts on this so it may be time to summarize some of my responses to your questions.

Input sensitivity is typically stated by manufacturers in several ways such as the following (I am using 1 V in the examples but it can 1.2, 1.5, 4 V or whatever):

1) 1 V, without saying anything else so you have to assume it is for the amp's rated power output, or something else. Examples where it is stated this simple but vague way: Some AVRs, such as Denon, Marantz, Yamaha, Onkyo, Anthem.
2) 1 V at 28.18 V output into 8 ohm, that is a better way but you have to understand that the maximum pre out voltage you need for this amp will depend on the power output you need. 28.18 V into 8 ohm will develop about 99.3 W (watts), so if you want the amp to output say about 200 W, you will need about 1.4 V. Parasound used this format for their input sensitivity spec, but they also provide the gain in dB so, can't complain..
3) 1 V for rated power output, in this case rated output generally mean rated output into 8 ohm. Anthem seem to do it this way, such as 1.5 V for 225 W, and 225 W is their rated output into 8 ohm, for the MCA 225, 325 or 525 amps.

4) Gain can be specified in multiples such as 10, 20, 28, or in dB (logarithmic) such as 10, 15, 26, 29 dB etc.
5) If you know the gain, you can calculate the input voltage, that is the preamp output voltage, required to drive the power amp to output its rated output (Watts).
http://www.sengpielaudio.com/calculator-FactorRatioLevelDecibel.htm has the formula you need.
6) Conversely, if you know the input sensitivity, stated in x volts input for the specified output (W), then you can calculate the gain.
7) The 0.7 V that Amir highlighted was the pre out voltage of the SR7015 that resulted in the highest SINAD achieved.
8) Just because the SR7015 (presumably your SR7013) perform the best in terms of SINAD at 0.7 V does not mean it can only produce 0.7 V. As you can see from the curve, at 2 V it still managed better than 75 dB SINAD, that is about as good as the so called separate prepro, namely the AV7705. It most likely can output higher than 4 V before "clipping".
9) The rms voltage of a music signal varies continuously, unless it is a test tone like a 1 kHz sine wave. So yes you can set the master volume on the SR7013 using a single tone (example: 1 kHz, or 2 kHz...) at a fixed input level, say 30 mVrms (0.03 V). If the input signal is a real music signal, then at any fixed master volume setting, such as -30, -20, 0, the output signal of the preamp, that is the so called pre out voltage, will vary with the input music signal. For example, if you connect a voltmeter to the pre out, set to master volume to say, -5 and observe the pre out voltage, you will see that it goes up and down continuously with the music signal. If the music is at its quietest moment/passage, the pre out voltage could be very low or 0 during the gap between tracks, and at its loudest moment the pre out voltage will be very high.

Point 9) is where you apparently got the misconception.

Let me know if this is clear now or you have any other specific questions related to this topic.
 

MacCali

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1.5 V input sensitivity for 225 W is practically the same as 29 dB gain.



Absolutely, volts, dB does the same thing mathematically if you know the math and if the manufacture states both the volts and the output W like Anthem did.
Since the calculations I did for you based on the information you provided were also based on 29 dB so the required pre out voltage for your AVR will be the same if you go with the MCA525, as long as you don't need go exceed your power amp's rated output that is 120 W into 8 ohms for the Denon POA 8300.

You only need 1.5 V if you crank the volume up to the point the MCA 525 will output 225 W.



I understand you may not have a strong background in the EE theories and math needed to understand some of the audio specs. There has been many posts on this so it may be time to summarize some of my responses to your questions.

Input sensitivity is typically stated by manufacturers in several ways such as the following (I am using 1 V in the examples but it can 1.2, 1.5, 4 V or whatever):

1) 1 V, without saying anything else so you have to assume it is for the amp's rated power output, or something else. Examples where it is stated this simple but vague way: Some AVRs, such as Denon, Marantz, Yamaha, Onkyo, Anthem.
2) 1 V at 28.18 V output into 8 ohm, that is a better way but you have to understand that the maximum pre out voltage you need for this amp will depend on the power output you need. 28.18 V into 8 ohm will develop about 99.3 W (watts), so if you want the amp to output say about 200 W, you will need about 1.4 V. Parasound used this format for their input sensitivity spec, but they also provide the gain in dB so, can't complain..
3) 1 V for rated power output, in this case rated output generally mean rated output into 8 ohm. Anthem seem to do it this way, such as 1.5 V for 225 W, and 225 W is their rated output into 8 ohm, for the MCA 225, 325 or 525 amps.

4) Gain can be specified in multiples such as 10, 20, 28, or in dB (logarithmic) such as 10, 15, 26, 29 dB etc.
5) If you know the gain, you can calculate the input voltage, that is the preamp output voltage, required to drive the power amp to output its rated output (Watts).
http://www.sengpielaudio.com/calculator-FactorRatioLevelDecibel.htm has the formula you need.
6) Conversely, if you know the input sensitivity, stated in x volts input for the specified output (W), then you can calculate the gain.
7) The 0.7 V that Amir highlighted was the pre out voltage of the SR7015 that resulted in the highest SINAD achieved.
8) Just because the SR7015 (presumably your SR7013) perform the best in terms of SINAD at 0.7 V does not mean it can only produce 0.7 V. As you can see from the curve, at 2 V it still managed better than 75 dB SINAD, that is about as good as the so called separate prepro, namely the AV7705. It most likely can output higher than 4 V before "clipping".
9) The rms voltage of a music signal varies continuously, unless it is a test tone like a 1 kHz sine wave. So yes you can set the master volume on the SR7013 using a single tone (example: 1 kHz, or 2 kHz...) at a fixed input level, say 30 mVrms (0.03 V). If the input signal is a real music signal, then at any fixed master volume setting, such as -30, -20, 0, the output signal of the preamp, that is the so called pre out voltage, will vary with the input music signal. For example, if you connect a voltmeter to the pre out, set to master volume to say, -5 and observe the pre out voltage, you will see that it goes up and down continuously with the music signal. If the music is at its quietest moment/passage, the pre out voltage could be very low or 0 during the gap between tracks, and at its loudest moment the pre out voltage will be very high.

Point 9) is where you apparently got the misconception.

Let me know if this is clear now or you have any other specific questions related to this topic.
I will definitely refer to this in the future. Hopefully the equipment I purchase will not even need this with provided measurements.

Yea this AVR is a bit tricky with a bell shaped sinad

Possibly my final question would be and maybe more simple or far more difficult to answer is would there be a way to upgrade the internals to increase the output stage?

Is it even worth it?

Would it even change the measurements or increase sinad to 2v?

I know this one maybe a very technical question.

Like I said previously, I am pleased with the unit and how it sounds since I have very little knowledge of what a higher measuring AVR can produce audibly. Trying to understand what I need for the best performance when I get that 4K player since the 7013 will be the bottleneck in measurements

Clearly it will be better with a dedicated player vs the nasty compressed audio from streaming, but I mean clearly we are all here to get maximum potential measurements and keep our wallets happy.
 

peng

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I will definitely refer to this in the future. Hopefully the equipment I purchase will not even need this with provided measurements.

Yea this AVR is a bit tricky with a bell shaped sinad

Possibly my final question would be and maybe more simple or far more difficult to answer is would there be a way to upgrade the internals to increase the output stage?

Is it even worth it?

There are always ways but a) you, or whoever is going to do it, have to know how. What you have is a 11.1 channel processing capable AVR, so imo, not worth it. You may be interested in finding out if you can hear the distortions from 60 dB SINAD, before you worry about your AVR's 75 dB SINAD at above 2 V output.

Obviously SINAD is just one thing to consider, there are other factors that could be more annoying than the distortion part of the equation.


Would it even change the measurements or increase sinad to 2v?

I know this one maybe a very technical question.

Like I said previously, I am pleased with the unit and how it sounds since I have very little knowledge of what a higher measuring AVR can produce audibly. Trying to understand what I need for the best performance when I get that 4K player since the 7013 will be the bottleneck in measurements

It isn't that technical at all but it is hard to answer such open ended questions, too many variables at play!

Clearly it will be better with a dedicated player vs the nasty compressed audio from streaming, but I mean clearly we are all here to get maximum potential measurements and keep our wallets happy.

Not all streaming audio are compressed, though the streaming service that provides uncompressed ones are typically paid services. Talking about that, I believe once to get pass the point of diminishing return on devices such as the higher mid range AVRs, or AVPs+power amps, and speakers, you will find that it is far more cost effective to spend on acquiring media contents (including those from streaming) that are of high quality recording/mastering than to chase the electronics.
 

MacCali

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There are always ways but a) you, or whoever is going to do it, have to know how. What you have is a 11.1 channel processing capable AVR, so imo, not worth it. You may be interested in finding out if you can hear the distortions from 60 dB SINAD, before you worry about your AVR's 75 dB SINAD at above 2 V output.

Obviously SINAD is just one thing to consider, there are other factors that could be more annoying than the distortion part of the equation.




It isn't that technical at all but it is hard to answer such open ended questions, too many variables at play!



Not all streaming audio are compressed, though the streaming service that provides uncompressed ones are typically paid services. Talking about that, I believe once to get pass the point of diminishing return on devices such as the higher mid range AVRs, or AVPs+power amps, and speakers, you will find that it is far more cost effective to spend on acquiring media contents (including those from streaming) that are of high quality recording/mastering than to chase the electronics.
Also figure that’s going to be costly and probably void the warranty possibly.

Honestly man, I am on here because I am very much for measurements. But as I point out on other threads I think people fully comprehend measurements.

I mention is my consistent repetition that you can easily assume that something with 80 db sinad is good sounding since in my experience I own an amp which has a sinad of 40. It was measured by Amir, and he even said I believe in the review or comments it’s one of the worst measuring amps he has ever tested.

Yet, before and after knowing this even with such a poor performance you would assume it sounds horrible, right?

Oddly I enjoy listening to it, this has very much perplexed me.

My main listening setup is world class measurements. So I get what this provides and do appreciate it very much. But even with being able to compare the two I do not feel that I don’t want to listen to that poorly measuring amp in my secondary setup
 

peng

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I mention is my consistent repetition that you can easily assume that something with 80 db sinad is good sounding since in my experience I own an amp which has a sinad of 40. It was measured by Amir, and he even said I believe in the review or comments it’s one of the worst measuring amps he has ever tested.

He also measured the ACA 5W amp designed by Nelson Pass. I had fun building it and thought it sounded great too if I use it with my KEF R900. When I tried it on my little KEF L50, it is almost not listenable unless I used it with a subwoofer.

SINAD of that thing is even less than 40 dB, more like 31 to 38 dB depending on the output and load impedance.

Yet, before and after knowing this even with such a poor performance you would assume it sounds horrible, right?

Oddly I enjoy listening to it, this has very much perplexed me.

My main listening setup is world class measurements. So I get what this provides and do appreciate it very much. But even with being able to compare the two I do not feel that I don’t want to listen to that poorly measuring amp in my secondary setup

Placebo effect is real so yes I feel the same way. I have been telling you in your application you shouldn't have to worry about the 75 dB SINAD at 2 V but why do you think I replaced my AV8801 (a Marantz prepro) with a Denon AVR-X4400H? There is no way I could tell the difference between the too in terms of sound quality, not even music. The only audible difference is the noise level. The Denon is practically silent from my even if I turn the volume up to +18 (max.) at less than 1 ft or a little further if the HVAC is off. The Marantz could be heard (same speakers) from my mlp that is 10-11 feet if I crank the volume to approach 0, say from -10 and higher. It didn't bother me as I never listened to anything at higher than -10 anyway, usually between -30 and -15 (rarely that high). So I understand why you want your amps and other devices to have the best possible measurements, me too. It is not about audible or not..
 

MacCali

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He also measured the ACA 5W amp designed by Nelson Pass. I had fun building it and thought it sounded great too if I use it with my KEF R900. When I tried it on my little KEF L50, it is almost not listenable unless I used it with a subwoofer.

SINAD of that thing is even less than 40 dB, more like 31 to 38 dB depending on the output and load impedance.



Placebo effect is real so yes I feel the same way. I have been telling you in your application you shouldn't have to worry about the 75 dB SINAD at 2 V but why do you think I replaced my AV8801 (a Marantz prepro) with a Denon AVR-X4400H? There is no way I could tell the difference between the too in terms of sound quality, not even music. The only audible difference is the noise level. The Denon is practically silent from my even if I turn the volume up to +18 (max.) at less than 1 ft or a little further if the HVAC is off. The Marantz could be heard (same speakers) from my mlp that is 10-11 feet if I crank the volume to approach 0, say from -10 and higher. It didn't bother me as I never listened to anything at higher than -10 anyway, usually between -30 and -15 (rarely that high). So I understand why you want your amps and other devices to have the best possible measurements, me too. It is not about audible or not..
I seen that one before, I think it’s neat to do DIY. Think they have an assembly video on YouTube. I really prefer class A sound and wanted to buy those, but all my speakers are pretty low sensitivity and 6 ohms so I decided to pass in an effort not to waste money

Again though, it may just be delusion but just hoping that when I get my 4K player it will be a massive improvement since everyone is always talking all this and that about blu ray players. Just particularly in the sound department.

I literally don’t even have enough free time throughout the day to go to the actual movie theaters even before covid. So really trying to maximize the experience.

Appreciate all your input, feedback, and effort.
 

peng

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Appreciate all your input, feedback, and effort.
Any time, good to know it helps..
By the way, I don't remember if we have covered the one thing you can do to improve SINAD for the pre out (on paper anyway) if you use the amp assign feature to disconnect the front left and right channel internal amps. It won't help as much as it can on Denon's but still can improve by a few dB (5 dB at 2 V) as shown in the graphs SINAD vs output voltage for the SR7015 and SR6014. The SR7013 should be comparable to that of the SR6014 as the it was launched only 1 year before the 6014.

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