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Marantz AV8805A Review (AV Processor)

peng

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I think my concern stems from audioholics and it seems that most denon or Marantz products which aren’t top tier, let’s just say Marantz since denon is doing better. Seems to have the internal amplifier clipping when the unit gets to 1.5 volts out.

I am guessing after your read is that the sinad will suffer but the unit will still function. Clipping is my only concern and I am not sure if he meant with the amp on or pre-amp mode

Edit: think I will do this for now, not sure if it will make a huge difference or not. I have a parasound HCA-1000 laying around and it’s input sensitivity is .775 for max output. I’ll run that on my LF and RF and put everything else on the 8300.

Not sure if I’ll run into any issues since the amps have different sensitivity

That's correct, at 1.4-1.5 V the internal amps will likely start to clip. The increased distortion would appear to be the reason for the preout SINAD to drop, quickly initially but would settle to about 70 to 75 dB at 2 to 4V, and then the preout itself would start to clip.

There should be no issues using your HCA-1000 with the 7015, both having comparable gain.

Parasound's input sensitivity spec is for 28.28 V, that is about 100 W 8 ohms. For the rated 125 W it would need about 1.1 V.

When looking at sensitivity specs you have to read the fine prints, as manufacturers may or may not specific the required preamp voltage for their power amp's rated output. Parasound's is a good example, though in this case the HCA-100 did provide the voltages for both 28.28 V and the rated 125 W. In other cases you may have to do your own calculations.
 
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MacCali

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That's correct, at 1.4-1.5 V the internal amps will likely start to clip. The increased distortion would appear to be the reason for the preout SINAD to drop, quickly initially but would settle to about 70 to 75 dB at 2 to 4V, and then the preout itself would start to clip.

There should be no issues using your HCA-1000 with the 7015, both having comparable gain.

Parasound's input sensitivity spec is for 28.28 V, that is about 100 W 8 ohms. For the rated 125 W it would need about 1.1 V.

When looking at sensitivity specs you have to read the fine prints, as manufacturers may or may not specific the required preamp voltage for their power amp's rated output. Parasound's is a good example, though in this case the HCA-100 did provide the voltages for both 28.28 V and the rated 125 W. In other cases you may have to do your own calculations.
Hmmmm on the hca-1000 manual it says .775 for full power, but maybe regarding the specs you can already know it’s higher.

Don’t have my home theater setup yet, took it down when I did a remodel and with work it’s been crazy busy to set up my theater room. Only got my stereo setup in there.
 

peng

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Hmmmm on the hca-1000 manual it says .775 for full power, but maybe regarding the specs you can already know it’s higher.

Don’t have my home theater setup yet, took it down when I did a remodel and with work it’s been crazy busy to set up my theater room. Only got my stereo setup in there.

I got the specs from the manual too but I could only find the one for the HCA-1000A, that has sensitivity of 1 V, 28.28 V. The HCA-750's sensitivity is 0.775 V but it is a lower value because it is rated 75 W.

The HCA-1000A is rated 125 W, what is your HCA-1000 rated for, according to the manual?

Regardless, even if it has a higher gain, it can still work with the SR7015 with no issue. By the way, you do realize adding such a low power amp won't do anything for you except it would help off load the AVR somewhat for multichannel use. For stereo, if it is rated 125 W, the SR7015 by itself is just as good, may even be better.
 

MacCali

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I got the specs from the manual too but I could only find the one for the HCA-1000A, that has sensitivity of 1 V, 28.28 V. The HCA-750's sensitivity is 0.775 V but it is a lower value because it is rated 75 W.

The HCA-1000A is rated 125 W, what is your HCA-1000 rated for, according to the manual?

Regardless, even if it has a higher gain, it can still work with the SR7015 with no issue. By the way, you do realize adding such a low power amp won't do anything for you except it would help off load the AVR somewhat for multichannel use. For stereo, if it is rated 125 W, the SR7015 by itself is just as good, may even be better.
But I am a tad confused here, maybe I missed something. But isn't the unit in pre amp mode getting better measurements? sinad

Edit: it says 80 db pre amp mode, and sinad vs measured level is 96 db at .7 volts am I missing something?
 
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peng

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But I am a tad confused here, maybe I missed something. But isn't the unit in pre amp mode getting better measurements? sinad

That is correct.

Edit: it says 80 db pre amp mode, and sinad vs measured level is 96 db at .7 volts am I missing something?

I am not sure if you are missing something as such..

If you are referring to the SR7015, SINAD was the same for both non pre-amp mode and pre-amp mode up to 1.5 V, but 4 to 5 dB better at 2 V for pre-amp mode. You can see that clearly in the SINAD vs Measured Level graph below.

The 80 dB SINAD was measured at about 2 V, in pre-amp mode, and about 75 dB in non pre-amp mode. Yes, at .7 V it was about 96 dB, all shown in the graph below.

75 dB SINAD is not really that bad, about the same as the AV7705. What is your concern?


index.php
 

MacCali

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That is correct.



I am not sure if you are missing something as such..

If you are referring to the SR7015, SINAD was the same for both non pre-amp mode and pre-amp mode up to 1.5 V, but 4 to 5 dB better at 2 V for pre-amp mode. You can see that clearly in the SINAD vs Measured Level graph below.

The 80 dB SINAD was measured at about 2 V, in pre-amp mode, and about 75 dB in non pre-amp mode. Yes, at .7 V it was about 96 dB, all shown in the graph below.

75 dB SINAD is not really that bad, about the same as the AV7705. What is your concern?


index.php
No concern really, just trying to get the best performance is all. I literally got amps just laying around and not in use. I just see it as might as well.

I actually have the 7013, it’s not measured but I’m sure it’s probably an equal performer.

Just trying something different really to see if there could be better performance. I don’t have a 4K player yet, never owned one. But I am going to be purchasing either the Panasonic ub9000/820 or Reavon xbr-200 as my main movie source so I am trying to maximize performance to decrease the bottleneck.

My only other option would be get the anthem avm 70 and more amps. Which seems pretty costly overall and I’m not watching movies the way I used too. Which would then put me in the 7000+ range so I see this as a better option by just using what I already got and not in use.
 

peng

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No concern really, just trying to get the best performance is all. I literally got amps just laying around and not in use. I just see it as might as well.
The wording "clipped..." used in those reviews misled (I am sure it was not intended) a lot of people.
I actually have the 7013, it’s not measured but I’m sure it’s probably an equal performer.
Can't prove it without the measurements but I bet you would be right. I think if100 WPC is all you need, pairing it with an external amp will take some load off but won't give you better sound quality. If you do need 200 W or more, then yes you should be able to hear "better" sound quality going with something rated for 250 to 350 W 8 ohm, 400 to 500 W 4 ohms. In that case, the SR7013 has high enough voltage as long as you go with amps that has gain of 28 dB or higher. Even those 26 dB gain Hypex amps will work, just SINAD would suffer a little at the high output but the increased distortion most likely would not audible anyway.
My only other option would be get the anthem avm 70 and more amps. Which seems pretty costly overall and I’m not watching movies the way I used too. Which would then put me in the 7000+ range so I see this as a better option by just using what I already got and not in use.
Again, can't prove it, but I bet you are right on this too if "better" sound quality is your goal, there isn't much point going with the Marantz av processors based on the test results. I am very happy with the Denon AVR with external amps now for my 7.1.4, but for the newer feature and the curiosity to try Anthem ARC, I may grab the AVM70 for Christmas. It won't be for sound quality, more for just wanting to try something different, for fun basically...
 

MacCali

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The wording "clipped..." used in those reviews misled (I am sure it was not intended) a lot of people.

Can't prove it without the measurements but I bet you would be right. I think if100 WPC is all you need, pairing it with an external amp will take some load off but won't give you better sound quality. If you do need 200 W or more, then yes you should be able to hear "better" sound quality going with something rated for 250 to 350 W 8 ohm, 400 to 500 W 4 ohms. In that case, the SR7013 has high enough voltage as long as you go with amps that has gain of 28 dB or higher. Even those 26 dB gain Hypex amps will work, just SINAD would suffer a little at the high output but the increased distortion most likely would not audible anyway.

Again, can't prove it, but I bet you are right on this too if "better" sound quality is your goal, there isn't much point going with the Marantz av processors based on the test results. I am very happy with the Denon AVR with external amps now for my 7.1.4, but for the newer feature and the curiosity to try Anthem ARC, I may grab the AVM70 for Christmas. It won't be for sound quality, more for just wanting to try something different, for fun basically...
Honestly I’ve never pushed any amp to clipping. But I do know what it is, and I’m not even certain why it would happen when the internal amps are not being used.

Second, I am guessing my volume bandwidth will decrease also if I use the avr in pre mode. So far my understanding is when I increase the volume the volts to the pre out begin to get higher. Since the parasound is .775v and my Denon is 1.1v for good power seems like it will play very loud way before max volume.

As mentioned I am not even two years into home audio, so please excuse my ignorance and also if I say certain things it’s not questioning your response. I am in no position to really do anything like that quite yet.

Yea I got no clue either we will find out, honestly didn’t know about measurements or ASR when I bought my AVR. My home theater was my first audio purchase. Subjective reviews all said Marantz was better and also I had no clue what I wanted in the sense I was like I want 11 channels. However my room is too small for that and I didn’t really take that into consideration. Just wanted a monster home theater system. I started with 5 channels and that was a huge upgrade over my previous sound bar. Later I grabbed a pair of height speakers and I’m more than satisfied with 7 channels.

Lastly, price was a factor as I had no work and this was 6 months into the pandemic. I actually got my 7013 open box for a 1000 dollars. I was on the audioholics forum trying to figure out what my options were to get a crazy amount of channels plus decent power and everyone there told me that was impossible under my budget.

But hey I pulled it off, plus my unit came with a 3 year warranty since I purchased from an authorized retailer.

What I got now is a 4K player is far better audio wise and visually too, so I am trying to get that to get a better experience. Also looking for a quality CD player at the same time, so getting an all in one solution.
 

peng

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Honestly I’ve never pushed any amp to clipping. But I do know what it is, and I’m not even certain why it would happen when the internal amps are not being used.

From wiki:


Clipping is a form of waveform distortion that occurs when an amplifier is overdriven and attempts to deliver an output voltage or current beyond its maximum capability. Driving an amplifier into clipping may cause it to output power in excess of its power rating.

So whether the internal amps are being used or not, when you over drive it the output voltage will clip. In preamp mode, the pre outs are disconnected from the power amp inputs so the increased harmonic distortions resulted from the clipped power amp voltage waveform will not affect the pre out voltage waveform via feedback or whatever ways.

Second, I am guessing my volume bandwidth will decrease also if I use the avr in pre mode. So far my understanding is when I increase the volume the volts to the pre out begin to get higher. Since the parasound is .775v and my Denon is 1.1v for good power seems like it will play very loud way before max volume.

Not necessarily, the .775 V is the input voltage required for the Parasound power amp to reach it's rated output. The HCA-1000A is rated 125 W, but I don't know what the HCA-1000 is rated for. I tried searching for the manual and cannot find it, can only find the one for the HCA-1000A. I suspect the specs of the HCA-1000 is quite different.

In the HCA-1000A manual, it specifies the input sensitivity for the HCA-1000A and HCA-750 as follow:

HCA-1000A
Continuous Power Output - Stereo
125 watts RMS x 2, 20 Hz-20 kHz, 8 W, both channels driven
Input Sensitivity
1 V for 28.28 V; THX Reference Level; 1.2 V for full output

HCA-750A
Continuous Power Output - Stereo
75 watts RMS x 2, 20 Hz-20 kHz, 8 W, both channels driven
Input Sensitivity
0.775 V for for full output

It may be possible that the HCA-1000 is rated 75 W, in that case it's gain would be about 30 dB, that is very close to that of the SR7013's 29 dB and at the same volume setting it may feel jus a touch louder, if at all.

Yea I got no clue either we will find out, honestly didn’t know about measurements or ASR when I bought my AVR. My home theater was my first audio purchase. Subjective reviews all said Marantz was better and also I had no clue what I wanted in the sense I was like I want 11 channels. However my room is too small for that and I didn’t really take that into consideration. Just wanted a monster home theater system. I started with 5 channels and that was a huge upgrade over my previous sound bar. Later I grabbed a pair of height speakers and I’m more than satisfied with 7 channels.

Lastly, price was a factor as I had no work and this was 6 months into the pandemic. I actually got my 7013 open box for a 1000 dollars. I was on the audioholics forum trying to figure out what my options were to get a crazy amount of channels plus decent power and everyone there told me that was impossible under my budget.

But hey I pulled it off, plus my unit came with a 3 year warranty since I purchased from an authorized retailer.

What I got now is a 4K player is far better audio wise and visually too, so I am trying to get that to get a better experience. Also looking for a quality CD player at the same time, so getting an all in one solution.

You've got yourself a good deal for sure. If you want to know more accurately at what pre out voltage you need for the power amp of your choice, you need to know the gain, or input sensitivity (in that case need to know the voltage for rated output, not just 0.775, 1, 1.2 V....). You would also need to know the output power you require, based on your listening habits, including the maximum spl you need, seating distance, and your speaker's sensitivity, impedance etc.

Then you can use a calculator such as:


 

MacCali

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From wiki:




So whether the internal amps are being used or not, when you over drive it the output voltage will clip. In preamp mode, the pre outs are disconnected from the power amp inputs so the increased harmonic distortions resulted from the clipped power amp voltage waveform will not affect the pre out voltage waveform via feedback or whatever ways.



Not necessarily, the .775 V is the input voltage required for the Parasound power amp to reach it's rated output. The HCA-1000A is rated 125 W, but I don't know what the HCA-1000 is rated for. I tried searching for the manual and cannot find it, can only find the one for the HCA-1000A. I suspect the specs of the HCA-1000 is quite different.

In the HCA-1000A manual, it specifies the input sensitivity for the HCA-1000A and HCA-750 as follow:

HCA-1000A
Continuous Power Output - Stereo
125 watts RMS x 2, 20 Hz-20 kHz, 8 W, both channels driven
Input Sensitivity
1 V for 28.28 V; THX Reference Level; 1.2 V for full output

HCA-750A
Continuous Power Output - Stereo
75 watts RMS x 2, 20 Hz-20 kHz, 8 W, both channels driven
Input Sensitivity
0.775 V for for full output

It may be possible that the HCA-1000 is rated 75 W, in that case it's gain would be about 30 dB, that is very close to that of the SR7013's 29 dB and at the same volume setting it may feel jus a touch louder, if at all.



You've got yourself a good deal for sure. If you want to know more accurately at what pre out voltage you need for the power amp of your choice, you need to know the gain, or input sensitivity (in that case need to know the voltage for rated output, not just 0.775, 1, 1.2 V....). You would also need to know the output power you require, based on your listening habits, including the maximum spl you need, seating distance, and your speaker's sensitivity, impedance etc.

Then you can use a calculator such as:


Oh crap I messed up, on the parasound website has 1000a and 750a owner manual combined. Thought that was one full list of specs.

So all these parasound amps new and old have gain adjustment, from what you are saying it’s best to keep it at maximum gain, cause less gain would create an issue.

To be honest I’m not really sure what that gain switch is actually doing. I believe a while back someone told me that it’s for preamp function or something along those lines. Can’t recall or understand what they were saying.

We don’t need to get into this last paragraph I think the previous question is more vital.

My denon poa8300 is thx rated too, why isn’t that unit 1 volt. I asked about this earlier on the 7015 or 8015 thread and someone pointed it’s higher

  • Power Output: 120W into 8Ω (3 channels)
  • Frequency Response: 1Hz to 100kHz
  • Distortion: 0.008%
  • Speaker Impedance: 4 to 16Ω
  • Input Sensitivity: 1.1V
  • Signal to Noise Ratio: 110dB
Now that we established that they are both almost 1 volt, sorry I know you said it earlier about the volts, but I thought you just read random specs. Just double checked now prior to posting this.

Would it better to use the denon on the front 3 channels and parasound on the rear or [second]is my FR/FL on parasound and C/SR/SL on the denon.

Only assuming the second one is better since the parasound has the lower input sensitivity it will get louder with cleaner performance from the avr. Guess .1 volts isn’t a huge factor
 

peng

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Oh crap I messed up, on the parasound website has 1000a and 750a owner manual combined. Thought that was one full list of specs.

So all these parasound amps new and old have gain adjustment, from what you are saying it’s best to keep it at maximum gain, cause less gain would create an issue.

To be honest I’m not really sure what that gain switch is actually doing. I believe a while back someone told me that it’s for preamp function or something along those lines. Can’t recall or understand what they were saying.

Yes, normally you should set those gain adjustment knobs to maximum and the input sensitivity specs are for the gain to be set to maximum.

In the manual, it says:

Level Controls
Each channel has its own rear mounted "set and forget" input level control. Your amplifier sounds best
with these level controls set to maximum, where they are effectively out of the audio signal path.
However, if your preamplifier has very high gain, and its volume control cannot track properly for leftright
channel balance near its minimum position, it may be necessary to reduce the input level control
settings on the amplifier. When using the HCA-1000A in a THX installation, each level control must be
set at maximum, which corresponds to 0 dB THX reference level.

Note that they called it level controls, in their newer models, they do call them gain control, that is more proper.
 

peng

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My denon poa8300 is thx rated too, why isn’t that unit 1 volt. I asked about this earlier on the 7015 or 8015 thread and someone pointed it’s higher

  • Power Output: 120W into 8Ω (3 channels)
  • Frequency Response: 1Hz to 100kHz
  • Distortion: 0.008%
  • Speaker Impedance: 4 to 16Ω
  • Input Sensitivity: 1.1V
  • Signal to Noise Ratio: 110dB
Now that we established that they are both almost 1 volt, sorry I know you said it earlier about the volts, but I thought you just read random specs. Just double checked now prior to posting this.

To be clear, based on the specs above, I would assume the Denon POA8300's 1.1 V input sensitivity is for it to output 120 W into 8 ohms at 0.008% THD, that is about -82 dB.
Marantz did not provide any sensitivity or gain specs in their manuals.

SR7013
According to the owner's manual:

1657729693447.png


So that 1.2 V seems to be a very generic spec just to indicate with 200 mV input, the preamp would output 1.2 V, no one knows what its maximum level is and at what distortions. Thanks to ASR and Audioholics, we know based on the measurements, the maximum appears to be around 4 V.

Would it better to use the denon on the front 3 channels and parasound on the rear or [second]is my FR/FL on parasound and C/SR/SL on the denon.

Only assuming the second one is better since the parasound has the lower input sensitivity it will get louder with cleaner performance from the avr. Guess .1 volts isn’t a huge factor

Again, you cannot say one is "louder" (assuming you do mean at the same volume setting, example: -10, 0, or whatever) than the other based on the input sensitivity only.
Take a look of the following example:

Amp A:
input sensitivity - 1 V, rated output V is 28.28V, and output power will be100 W (by calculation using the power formula P = V^2/R, that is 28.28X28.28/8 = 100 W.

Amp B:
input sensitivity - 2 V, rated output V is 56.37 V, and output power will be 397 W (56.37*56.67/8 = 397 W

So Amp A has much lower (half) input sensitivity figure, but because it is rated 100 W vs Amp B's 400 W, the two will be equally loud at the same volume setting, up to the point when both output 100 W, after that, Amp B will be louder if you keep turning the master volume up.

Now back to the two amps you are comparing, since the specs show the Denon POA8300 and the internal amps of the SR7013 are rated about 120 and 125 W respectively and the gain of the Denon is about 31 dB, that's 2 dB higher than the SR7013's 29 dB (again Marantz never provided the specs, the 29 dB is my best educated guess), so if I guess correctly, then you would be right, that at the same volume setting, the Denon amp will be a little louder.
 

peng

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@MacCali , I think the following practical example based on my own HT system may put things into perspective for you, at least to some extent I hope..

I typically listen to about 70 dB average, 90 dB peak when watching movies.
The specs of my speakers have sensitivity of about 87 dB/2.83V/m and my mmp is 10.5 ft from the front L/R speakers.

I only need 0.1 W, to achieve 70 dB spl and 10 W for the 90 dB peak spl.
From calculations, the pre out voltage I need would be less than 0.32 Vrms. for the 90 dB peak

That means for me, SINAD in the low range from 0 to 1 V is much more important than that in the 1 to 2 V range.

Now if I were to watch the same movie at THX reference level, that is 85 dB average, 105 dB peak, then my power requirement for the front left, or right speaker will go up to
about 3.3 W, or 330 W to allow for 20 dB peak on top of the 85 dB average spl. I will never do that as it would be much too loud for me, even 80 dB average is too loud for me.

And under such condition, the corresponding pre out voltage required will be 0.182 V for 85 dB spl at my mmp, or 1.82 V to achieve the peak output of 330 W for the 105 dB SPL. So in that case, if I were to minimize the chance of the power amp clipping I would need a 350 W rated one such as the NC502MP Hypex amps. Pre out voltage still not much of a concern because any of those Denon or Marantz measured on ASR can output more than 2 V with SINAD >75 dB without using preamp mode.

Please also keep in mind that music and movie signals are not continuous sine waves with constant magnitudes. So even if you need pre out voltage of 2 V or higher, it will be for the short duration peaks only, such as the explosion, car chase, crash scenes.

The above example is based on my HT setup, yours could be much different because the results depend a lot on your speakers, distance and your listening habits. If you are interested in doing your own calculations for your applicable parameters, take a look of the following website that has probably >90% of the formula you would ever need for audio.

 
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MacCali

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Now @peng I think possibly my final question would be is there any way for me to measure the output voltage on my avr? can I use that electric meter? I think on an article I read that you put the hot pin into the female portion and the negative onto the surrounding metal. Not sure if this is realistic or feasible.

How can I figure out when the unit is actually outputting .7 volts, I may have this whole thing mixed up. But the volts increase as you increase the volume correct?
 

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I absolutely was not comparing the 2 I neither mentioned similarites or differencences. Frankly I don't care. You misread all of that and incorrectly construed it as technical discussion about the relative merits of the DACs. It was not. You've gotten way to far down in the weeds on this one. You're perfect example of at least one of my points though. Instead of the main thrust of what I wrote you zeroed in on the DACs...only. As a matter of fact this entire thread is about the 8805A so if you mean a long time as being prior to the previous 13 pages of posts I don't quite understand.
As an aside on the Denton vs Marantz measurement discussion , functionality vs price is also a consideration (for me). I have a slimline Marantz NR1608 - it has a trigger out (to turn on my Devialet), front pre outs (to hook into my 2 channel system) and dual sub outputs. You need to go up the Denon range to get the same functionality (3700 I think) which is 50% more than the current Marantz NR1711 (equivalent of my old 1608). Just another angle which might be relevant to some. Pretty sure the slimline Marantz will measure like c*** , but it’s good enough for TV work :)
 

peng

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Now @peng I think possibly my final question would be is there any way for me to measure the output voltage on my avr? can I use that electric meter? I think on an article I read that you put the hot pin into the female portion and the negative onto the surrounding metal. Not sure if this is realistic or feasible.
I measured it with a multimeter as shown in the photo below:

asr1.jpg
asr2.jpg


The first one, 212.7 mV, or 0.2127 V was when playing a loud part of a violin concerto and the 2nd one, the 51 mV was taken when playing the test tone with volume set to just below 0. Why are you so keen on .7 V? As you know music signal varies all the time, the pre out voltage will fluctuate between 0 and a few volts, if you don't listen to reference level and media content that have very high dynamics, it may not reach .7 V for you.

How can I figure out when the unit is actually outputting .7 volts, I may have this whole thing mixed up. But the volts increase as you increase the volume correct?

It depends on the media contents. As another example, for pre out voltage = .7 V, your Denon POA 8300 will output 120 W into an 8 ohm resistor load.
POA 8300 output voltage = square root (120*8) = 31 V
POA 8300 gain = Vo/Vi = 31/1.1 = 28.182, or 29 dB (gain in dB = 20*log10(gain in multiples)

Knowing the output power, and the gain/input sensitivity of the power amp, you can work backward to get the pre out voltage using the power formula P = (V^2)/R and/or with some of those spl/power requirement online calculators linked before:

As an example, you can easily set up an Excel table as shown below:

Power output (W into 8 ohm)Voltage outputPre out voltage = Power amp out/gainSPL at 4 m
12.8280.1078
24.000.1481
45.660.2084
88.000.2887
1611.310.4090
3216.000.5793
4819.600.7094.8
9627.710.9897.8
10028.281.0098
12030.981.1098.7
19239.191.39100.8
50063.252.24104.9

What is the sensitivity of your speakers? For now if assume it is 90 dB/2.83V/1m, then with pre out voltage = 0.7 V, the POA 8300 will output 48 W into 8 ohms or 96 W into 4 ohms. Again, depending on the sensitivity of your speakers, distance, and the spl you need, you may not need .7 V even for the peaks in the contents you listen to.
 
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MacCali

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I measured it with a multimeter as shown in the photo below:

View attachment 218654View attachment 218655

The first one, 212.7 mV, or 0.2127 V was when playing a loud part of a violin concerto and the 2nd one, the 51 mV was taken when playing the test tone with volume set to just below 0. Why are you so keen on .7 V? As you know music signal varies all the time, the pre out voltage will fluctuate between 0 and a few volts, if you don't listen to reference level and media content that have very high dynamics, it may not reach .7 V for you.



It depends on the media contents. As another example, for pre out voltage = .7 V, your Denon POA 8300 will output 120 W into an 8 ohm resistor load.
POA 8300 output voltage = square root (120*8) = 31 V
POA 8300 gain = Vo/Vi = 31/1.1 = 28.182, or 29 dB (gain in dB = 20*log10(gain in multiples)

Knowing the output power, and the gain/input sensitivity of the power amp, you can work backward to get the pre out voltage using the power formula P = (V^2)/R and/or with some of those spl/power requirement online calculators linked before:

As an example, you can easily set up an Excel table as shown below:

Power output (W into 8 ohm)Voltage outputPre out voltage = Power amp out/gainSPL at 4 m
12.8280.1078
24.000.1481
45.660.2084
88.000.2887
1611.310.4090
3216.000.5793
4819.600.7094.8
9627.710.9897.8
10028.281.0098
12030.981.1098.7
19239.191.39100.8
50063.252.24104.9

What is the sensitivity of your speakers? For now if assume it is 90 dB/2.83V/1m, then with pre out voltage = 0.7 V, the POA 8300 will output 48 W into 8 ohms or 96 W into 4 ohms. Again, depending on the sensitivity of your speakers, distance, and the spl you need, you may not need .7 V even for the peaks in the contents you listen to.
Oh, I was unaware it changes. Thought at set volume you get specific voltage out. But I do understand what you mean. I think based on this incorrect thought process I would be able to get better performance higher sinad at a specific volume which would output .7 v.

I very much appreciate your effort, and have actually learned something new. I guess if I understood this from the get go it would have been far better to avoid this.

I guess now that Amir mentioning make sure the external amp reaches full power at .7 volts so as you turn the dial to max the performance will only increase and not loop back down like the graph.

My speakers are 85 dB at 2.83 v/1m and 6 ohm.

I don’t know where I would be but at -15, I believe my unit goes in db rather than 1-100 I usually get super loud at -15. My room is not very large and I am about 7 feet from my 3 front speakers
 

peng

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Oh, I was unaware it changes. Thought at set volume you get specific voltage out. But I do understand what you mean. I think based on this incorrect thought process I would be able to get better performance higher sinad at a specific volume which would output .7 v.

I didn't know you weren't aware of that fact, no wonder you got fixated on the SINAD at 0.7 V.

My speakers are 85 dB at 2.83 v/1m and 6 ohm.

I don’t know where I would be but at -15, I believe my unit goes in db rather than 1-100 I usually get super loud at -15. My room is not very large and I am about 7 feet from my 3 front speakers

In that case, you should get about 77 dB SPL at 7 feet from just 1 speaker, with 1 W.

For 6 ohms, the power amp output voltage would be 2.45 Vrms and the input voltage, that is the pre out voltage from your AVR will be just 0.0869 Vrms.

Seems incredibly low, but that's what the calculations show. Note that this is for 77 dB SPL, if you allow for 20 dB peaks, then the power amp output would need to be 100 W, and the pre out voltage required will be 0.869 Vrms, that is, exceeding 0.7V. Still, at 0.869 V, SINAD will be in the high 90's. You are in great shape regardless..
 
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MacCali

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I didn't know you weren't aware of that fact, no wonder you got fixated on the SINAD at 0.7 V.



In that case, you should get about 77 dB SPL at 7 feet from just 1 speaker, with 1 W.

For 6 ohms, the power amp output voltage would be 2.45 Vrms and the input voltage, that is the pre out voltage from your AVR will be just 0.0869 Vrms.

Seems incredibly low, but that's what the calculations show. Note that this is for 77 dB SPL, if you allow for 20 dB peaks, then the power amp output would need to be 100 W, and the pre out voltage required will be 0.869 Vrms, that is, exceeding 0.7V. Still, at 0.869 V, SINAD will be in the high 90's. You are in great shape regardless..
LOL you’re like what the is this guy talking about

I guess that’s still better than what the unit itself produces. Fortunately since this is a niche situation I wouldn’t need to get too deep into this but will definitely reference it.

I will get avm 70 eventually, unfortunately I have to save up for a few other things.

Also your voltage response is for my specific amps and speaker correct? If I choose a higher input sensitivity amp these numbers will change, if I wanted more powerful amp

Final question
 

peng

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LOL you’re like what the is this guy talking about

I guess that’s still better than what the unit itself produces. Fortunately since this is a niche situation I wouldn’t need to get too deep into this but will definitely reference it.

I will get avm 70 eventually, unfortunately I have to save up for a few other things.

Also your voltage response is for my specific amps and speaker correct?

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.

If I choose a higher input sensitivity amp these numbers will change, if I wanted more powerful 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..
 
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